System.Data.SQLite

<configuration>
  <system.data>
    <DbProviderFactories>
      <remove invariant="System.Data.SQLite"/>
      <add name="SQLite Data Provider" invariant="System.Data.SQLite" 
           description=".Net Framework Data Provider for SQLite"
           type="System.Data.SQLite.SQLiteFactory, System.Data.SQLite,
                 Version=1.0.53.0, Culture=neutral,
                 PublicKeyToken=db937bc2d44ff139"/>
    </DbProviderFactories>
  </system.data>
</configuration>
</pre>
      </div>
      <p>

          </td>
        </tr>
      </table>
    </div>
    <div id="mainSection">
    <div id="mainBody">
    <h1 class="heading">Version History</h1>
    <p><b>1.0.53.0 - July 24, 2008</b></p>
    <ul>
      <li>Enabled sqlite_load_extension</li>
      <li>Added retry/timeout code to SQLite3.Prepare() when preparing statements for 
        execution and a SQLITE_BUSY error occurs.</li>
      <li>Added a new schema to SQLiteConnection.GetSchema() called <i>Triggers</i>.&nbsp; 
        Used to retrieve the trigger(s) associated with a database and/or table/view.</li>
      <li>Extensive updates to table/view editing capabilities inside Visual Studio&#39;s 
        Server Explorer.&nbsp; The program now parses and lets you edit CHECK constraints and 
        triggers on a table, as well as define triggers on views.&nbsp; Experimental 
        still, so e-mail me if you have issues.</li>
      <li>Minor bugfix to the ViewColumns schema to return the proper base column name 
        for a view that aliases a column.</li>
      <li>Fixed the insert/update/delete DML support in the Linq module.</li>
      <li>Changed the behavior of SQLiteCommand to allow a transaction to be set even if 
        the command hasn&#39;t been associated with a connection yet.</li>
    </ul>
    <p><b>1.0.52.0 - July 16, 2008</b></p>
    <ul>
      <li>Code merge with SQLite 3.6.0</li>
      <li>Added a lot of previously-missing exports to the DEF file for the 
        native library.</li>
      <li>Fixed SQLiteDataReader to check for an invalid connection before operating on 
        an open cursor.</li>

      </DIV>
      <h1 class="heading">What's New?</h1>
      <p><a href="version.html">Click here to see the version history of this SQLite.NET 
          provider</a></p>
      <DIV>
        <br>
      </DIV>










      <h1 class="heading">Using this library</h1>
      <p>The following are links to information on various aspects of the library and 
        how to use it in your application(s)
      </p>
      <p><a href="designer.html">How to install&nbsp;Visual Studio Design-Time Support</a></p>
      <P><A href="dbfactorysupport.html">How to configure and enumerate SQLite.NET 
          through the DbProviderFactories object</A></P>

        <LI>
        Written from scratch on VS2005/2008 specifically for ADO.NET 2.0, implenting all the
        base classes and features recently introduced in the framework, including automatic
        transaction enlistment.<li>Supports the Full and Compact .NET Framework, as well as
          native C/C++ development.&nbsp; 100% binary compatible with the original sqlite3.dll.
        </li>
        <li>
        On the Compact Framework, it is faster than Sql Server Mobile.
          SQLite's installed size is a fraction of Sql Mobile's. It uses less memory at runtime,
          runs queries faster, and has a smaller database file size as well. </li>
        <li>Encrypted database support.&nbsp; Encrypted databases are fully encrypted and
          support both binary and cleartext password types. </li>
        <li>Visual Studio 2005/2008 Design-Time Support.&nbsp; You can add a SQLite 
        database to the Servers list, design queries with the Query Designer, 
        drag-and-drop tables onto a Typed DataSet, etc.</li>
            <li>Full SQLite schema editing inside Visual Studio.&nbsp; You can create/edit 
              tables, views, triggers, indexes, check constraints and foreign keys. </li>
        <li>
        Single file redistributable.&nbsp; The core sqlite3 codebase and the ADO.NET wrapper 
        are combined into one multi-module assembly. </li>
        <li>Binaries included for Itanium, x64, x86 and ARM processors. </li>
        <li>
        DbProviderFactory support. </li>
        <li>
          Full support for ATTACH'ed databases.&nbsp; Exposed as <i>Catalogs</i>
        in the schema.&nbsp; When cloning a connection, all attached databases are 
        automatically re-attached to the new connection. </li>
        <li>
          DbConnection.GetSchema(...) support includes the <i>MetaDataCollections</i>, <i>
          DataSourceInformation</i>, <i>Columns</i>, <i>Tables</i>, <i>Views, ViewColumns, </i>
          <i>Catalogs, </i><i>Indexes, 
            IndexColumns, ForeignKeys </i>and <em>Triggers</em>.

        </li>
        <li>
        Enhanced DbDataReader.GetSchemaTable() functionality returns catalog, namespace 
        and detailed schema information even for complex queries. </li>
        <li>
        Named and unnamed parameters. </li>
        <li>

/********************************************************
 * ADO.NET 2.0 Data Provider for SQLite Version 3.X
 * Written by Robert Simpson (robert@blackcastlesoft.com)
 * 
 * Released to the public domain, use at your own risk!
 ********************************************************/

namespace SQLite.Designer
{
  using System;
  using System.Collections.Generic;
  using System.ComponentModel;
  using System.Data;
  using System.Drawing;

namespace SQLite.Designer
{
  partial class ChangeScriptDialog
  {
    /// <summary>
    /// Required designer variable.
    /// </summary>
    private System.ComponentModel.IContainer components = null;

    /// <summary>
    /// Clean up any resources being used.
    /// </summary>
    /// <param name="disposing">true if managed resources should be disposed; otherwise, false.</param>
    protected override void Dispose(bool disposing)
    {
      if (disposing && (components != null))
      {
        components.Dispose();
      }
      base.Dispose(disposing);
    }

    #region Windows Form Designer generated code

    /// <summary>
    /// Required method for Designer support - do not modify
    /// the contents of this method with the code editor.
    /// </summary>
    private void InitializeComponent()
    {
      System.Windows.Forms.PictureBox pictureBox1;
      System.Windows.Forms.Label label1;
      System.Windows.Forms.Button noButton;
      System.Windows.Forms.Button yesButton;
      this._script = new System.Windows.Forms.RichTextBox();
      pictureBox1 = new System.Windows.Forms.PictureBox();
      label1 = new System.Windows.Forms.Label();
      noButton = new System.Windows.Forms.Button();
      yesButton = new System.Windows.Forms.Button();
      ((System.ComponentModel.ISupportInitialize)(pictureBox1)).BeginInit();
      this.SuspendLayout();
      // 
      // pictureBox1
      // 
      pictureBox1.Image = global::SQLite.Designer.VSPackage.info;
      pictureBox1.Location = new System.Drawing.Point(13, 13);
      pictureBox1.Name = "pictureBox1";
      pictureBox1.Size = new System.Drawing.Size(48, 48);
      pictureBox1.SizeMode = System.Windows.Forms.PictureBoxSizeMode.AutoSize;
      pictureBox1.TabIndex = 0;
      pictureBox1.TabStop = false;
      // 
      // label1
      // 
      label1.AutoSize = true;
      label1.Location = new System.Drawing.Point(67, 31);
      label1.Name = "label1";
      label1.Size = new System.Drawing.Size(200, 13);
      label1.TabIndex = 1;
      label1.Text = "Do you want to save this script to a file?";
      // 
      // noButton
      // 
      noButton.DialogResult = System.Windows.Forms.DialogResult.Cancel;
      noButton.Location = new System.Drawing.Point(445, 362);
      noButton.Name = "noButton";
      noButton.Size = new System.Drawing.Size(75, 25);
      noButton.TabIndex = 3;
      noButton.Text = "&No";
      noButton.UseVisualStyleBackColor = true;
      noButton.Click += new System.EventHandler(this.noButton_Click);
      // 
      // yesButton
      // 
      yesButton.Location = new System.Drawing.Point(364, 362);
      yesButton.Name = "yesButton";
      yesButton.Size = new System.Drawing.Size(75, 25);
      yesButton.TabIndex = 4;
      yesButton.Text = "&Yes";
      yesButton.UseVisualStyleBackColor = true;
      yesButton.Click += new System.EventHandler(this.yesButton_Click);
      // 
      // _script
      // 
      this._script.BorderStyle = System.Windows.Forms.BorderStyle.FixedSingle;
      this._script.Font = new System.Drawing.Font("Courier New", 8.25F, System.Drawing.FontStyle.Regular, System.Drawing.GraphicsUnit.Point, ((byte)(0)));
      this._script.Location = new System.Drawing.Point(12, 76);
      this._script.Name = "_script";
      this._script.ReadOnly = true;
      this._script.Size = new System.Drawing.Size(508, 280);
      this._script.TabIndex = 2;
      this._script.Text = "";
      this._script.WordWrap = false;
      // 
      // ChangeScriptDialog
      // 
      this.AcceptButton = yesButton;
      this.AutoScaleDimensions = new System.Drawing.SizeF(6F, 13F);
      this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font;
      this.CancelButton = noButton;
      this.ClientSize = new System.Drawing.Size(532, 399);
      this.Controls.Add(yesButton);
      this.Controls.Add(noButton);
      this.Controls.Add(this._script);
      this.Controls.Add(label1);
      this.Controls.Add(pictureBox1);
      this.Font = new System.Drawing.Font("MS Shell Dlg 2", 8.25F, System.Drawing.FontStyle.Regular, System.Drawing.GraphicsUnit.Point, ((byte)(0)));
      this.FormBorderStyle = System.Windows.Forms.FormBorderStyle.FixedDialog;
      this.MaximizeBox = false;
      this.MinimizeBox = false;
      this.Name = "ChangeScriptDialog";
      this.StartPosition = System.Windows.Forms.FormStartPosition.CenterParent;
      this.Text = "Save Change Script";
      ((System.ComponentModel.ISupportInitialize)(pictureBox1)).EndInit();
      this.ResumeLayout(false);
      this.PerformLayout();

    }

    #endregion

    private System.Windows.Forms.RichTextBox _script;

  }
}

/********************************************************
 * ADO.NET 2.0 Data Provider for SQLite Version 3.X
 * Written by Robert Simpson (robert@blackcastlesoft.com)
 * 
 * Released to the public domain, use at your own risk!
 ********************************************************/

namespace SQLite.Designer
{
  using System;
  using System.Collections.Generic;
  using System.ComponentModel;
  using System.Data;
  using System.Drawing;
  using System.Text;
  using System.Windows.Forms;
  using SQLite.Designer.Design;

  public partial class ChangeScriptDialog : Form
  {
    private string _tableName;

    public ChangeScriptDialog(string tableName, string script)
    {
      _tableName = tableName;
      InitializeComponent();

      _script.Text = script;
    }

    private void noButton_Click(object sender, EventArgs e)
    {
      DialogResult = DialogResult.Cancel;
      Close();
    }

    private void yesButton_Click(object sender, EventArgs e)
    {
      using (SaveFileDialog save = new SaveFileDialog())
      {
        save.DefaultExt = "sql";
        save.OverwritePrompt = true;
        save.Filter = "SQL Script Files (*.sql)|*.sql|All Files (*.*)|*.*";
        save.FileName = String.Format("{0}.sql", _tableName);
        save.Title = "Save SQLite Change Script";

        DialogResult = save.ShowDialog(this);

        if (DialogResult == DialogResult.OK)
        {
          System.IO.File.WriteAllText(save.FileName, _script.Text.Replace("\r", "").Replace("\n", "\r\n"), Encoding.UTF8);
        }
      }
      Close();
    }
  }
}

<?xml version="1.0" encoding="utf-8"?>
<root>
  <!-- 
    Microsoft ResX Schema 
    
    Version 2.0
    
    The primary goals of this format is to allow a simple XML format 
    that is mostly human readable. The generation and parsing of the 
    various data types are done through the TypeConverter classes 
    associated with the data types.
    
    Example:
    
    ... ado.net/XML headers & schema ...
    <resheader name="resmimetype">text/microsoft-resx</resheader>
    <resheader name="version">2.0</resheader>
    <resheader name="reader">System.Resources.ResXResourceReader, System.Windows.Forms, ...</resheader>
    <resheader name="writer">System.Resources.ResXResourceWriter, System.Windows.Forms, ...</resheader>
    <data name="Name1"><value>this is my long string</value><comment>this is a comment</comment></data>
    <data name="Color1" type="System.Drawing.Color, System.Drawing">Blue</data>
    <data name="Bitmap1" mimetype="application/x-microsoft.net.object.binary.base64">
        <value>[base64 mime encoded serialized .NET Framework object]</value>
    </data>
    <data name="Icon1" type="System.Drawing.Icon, System.Drawing" mimetype="application/x-microsoft.net.object.bytearray.base64">
        <value>[base64 mime encoded string representing a byte array form of the .NET Framework object]</value>
        <comment>This is a comment</comment>
    </data>
                
    There are any number of "resheader" rows that contain simple 
    name/value pairs.
    
    Each data row contains a name, and value. The row also contains a 
    type or mimetype. Type corresponds to a .NET class that support 
    text/value conversion through the TypeConverter architecture. 
    Classes that don't support this are serialized and stored with the 
    mimetype set.
    
    The mimetype is used for serialized objects, and tells the 
    ResXResourceReader how to depersist the object. This is currently not 
    extensible. For a given mimetype the value must be set accordingly:
    
    Note - application/x-microsoft.net.object.binary.base64 is the format 
    that the ResXResourceWriter will generate, however the reader can 
    read any of the formats listed below.
    
    mimetype: application/x-microsoft.net.object.binary.base64
    value   : The object must be serialized with 
            : System.Runtime.Serialization.Formatters.Binary.BinaryFormatter
            : and then encoded with base64 encoding.
    
    mimetype: application/x-microsoft.net.object.soap.base64
    value   : The object must be serialized with 
            : System.Runtime.Serialization.Formatters.Soap.SoapFormatter
            : and then encoded with base64 encoding.

    mimetype: application/x-microsoft.net.object.bytearray.base64
    value   : The object must be serialized into a byte array 
            : using a System.ComponentModel.TypeConverter
            : and then encoded with base64 encoding.
    -->
  <xsd:schema id="root" xmlns="" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:msdata="urn:schemas-microsoft-com:xml-msdata">
    <xsd:import namespace="http://www.w3.org/XML/1998/namespace" />
    <xsd:element name="root" msdata:IsDataSet="true">
      <xsd:complexType>
        <xsd:choice maxOccurs="unbounded">
          <xsd:element name="metadata">
            <xsd:complexType>
              <xsd:sequence>
                <xsd:element name="value" type="xsd:string" minOccurs="0" />
              </xsd:sequence>
              <xsd:attribute name="name" use="required" type="xsd:string" />
              <xsd:attribute name="type" type="xsd:string" />
              <xsd:attribute name="mimetype" type="xsd:string" />
              <xsd:attribute ref="xml:space" />
            </xsd:complexType>
          </xsd:element>
          <xsd:element name="assembly">
            <xsd:complexType>
              <xsd:attribute name="alias" type="xsd:string" />
              <xsd:attribute name="name" type="xsd:string" />
            </xsd:complexType>
          </xsd:element>
          <xsd:element name="data">
            <xsd:complexType>
              <xsd:sequence>
                <xsd:element name="value" type="xsd:string" minOccurs="0" msdata:Ordinal="1" />
                <xsd:element name="comment" type="xsd:string" minOccurs="0" msdata:Ordinal="2" />
              </xsd:sequence>
              <xsd:attribute name="name" type="xsd:string" use="required" msdata:Ordinal="1" />
              <xsd:attribute name="type" type="xsd:string" msdata:Ordinal="3" />
              <xsd:attribute name="mimetype" type="xsd:string" msdata:Ordinal="4" />
              <xsd:attribute ref="xml:space" />
            </xsd:complexType>
          </xsd:element>
          <xsd:element name="resheader">
            <xsd:complexType>
              <xsd:sequence>
                <xsd:element name="value" type="xsd:string" minOccurs="0" msdata:Ordinal="1" />
              </xsd:sequence>
              <xsd:attribute name="name" type="xsd:string" use="required" />
            </xsd:complexType>
          </xsd:element>
        </xsd:choice>
      </xsd:complexType>
    </xsd:element>
  </xsd:schema>
  <resheader name="resmimetype">
    <value>text/microsoft-resx</value>
  </resheader>
  <resheader name="version">
    <value>2.0</value>
  </resheader>
  <resheader name="reader">
    <value>System.Resources.ResXResourceReader, System.Windows.Forms, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089</value>
  </resheader>
  <resheader name="writer">
    <value>System.Resources.ResXResourceWriter, System.Windows.Forms, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089</value>
  </resheader>
  <metadata name="pictureBox1.GenerateMember" type="System.Boolean, mscorlib, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089">
    <value>False</value>
  </metadata>
  <metadata name="label1.GenerateMember" type="System.Boolean, mscorlib, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089">
    <value>False</value>
  </metadata>
  <metadata name="noButton.GenerateMember" type="System.Boolean, mscorlib, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089">
    <value>False</value>
  </metadata>
  <metadata name="yesButton.GenerateMember" type="System.Boolean, mscorlib, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089">
    <value>False</value>
  </metadata>
</root>

/********************************************************
 * ADO.NET 2.0 Data Provider for SQLite Version 3.X
 * Written by Robert Simpson (robert@blackcastlesoft.com)
 * 
 * Released to the public domain, use at your own risk!
 ********************************************************/

namespace SQLite.Designer.Design
{
  using System;
  using System.Collections.Generic;
  using System.Collections;
  using System.Text;
  using System.ComponentModel;
  using System.Data;
  using System.Data.Common;
  using System.ComponentModel.Design;
  using System.Drawing.Design;
  using System.Windows.Forms;

  internal class CheckEditor : CollectionEditor
  {
    Table _table;
    CollectionEditor.CollectionForm _form;
    object[] _items;
    object[] _orig;
    int _count;

    internal CheckEditor(Table parent)
      : base(typeof(List<string>))
    {
      _table = parent;
    }

    protected override CollectionEditor.CollectionForm CreateCollectionForm()
    {
      _form = base.CreateCollectionForm();
      _form.Text = "CHECK Constraint Editor";
      _form.Width = (int)(_form.Width * 1.25);
      _form.Height = (int)(_form.Height * 1.25);
      return _form;
    }

    protected override object CreateInstance(Type itemType)
    {
      if (itemType == typeof(string)) return String.Empty;
      return base.CreateInstance(itemType);
    }

    protected override object[] GetItems(object editValue)
    {
      if (_items == null)
      {
        List<string> items = editValue as List<string>;
        _items = new object[items.Count];
        _orig = new object[items.Count];

        for (int n = 0; n < _items.Length; n++)
        {
          _items[n] = items[n];
          _orig[n] = items[n];
        }
        _count = _items.Length;
      }
      return _items;
    }

    protected override object SetItems(object editValue, object[] value)
    {
      bool dirty = false;
      if (editValue != null)
      {
        int length = this.GetItems(editValue).Length;
        int num2 = value.Length;
        if (!(editValue is IList))
        {
          return editValue;
        }
        IList list = (IList)editValue;
        list.Clear();
        for (int i = 0; i < value.Length; i++)
        {
          string val = value[i] as string;

          if (String.IsNullOrEmpty(val) == false)
          {
            list.Add(val);
            if (i < _orig.Length && val != (string)_orig[i])
              dirty = true;
          }
        }
        if (list.Count != _count)
          dirty = true;

        if (dirty == true && _form.DialogResult == DialogResult.OK)
          _table._owner.MakeDirty();
      }
      return editValue;
    }
  }
}

/********************************************************
 * ADO.NET 2.0 Data Provider for SQLite Version 3.X
 * Written by Robert Simpson (robert@blackcastlesoft.com)
 * 
 * Released to the public domain, use at your own risk!
 ********************************************************/

namespace SQLite.Designer.Design
{
  using System;
  using System.Collections.Generic;
  using System.Text;
  using System.ComponentModel;
  using System.ComponentModel.Design;
  using System.Windows.Forms;
  using System.Drawing.Design;
  using System.Data;
  using System.Data.Common;



  internal class Column : IHaveConnection
  {
    private bool _allowNulls = false;
    private string _dataType = "";
    private string _defaultValue = "";
    private string _columnName = "";
    private string _origName = "";
    private string _collate;
    private DataGridViewRow _parent;

    private Unique _unique;

    private Table _table;

    internal Column(Table table, DataGridViewRow row)
    {
      _parent = row;
      _table = table as Table;
      _unique = new Unique(this);

    }

    internal Column(DataRow row, Table source)
    {
      _table = source;
      _unique = new Unique(this, row);


      if (row.IsNull("AUTOINCREMENT") == false && (bool)row["AUTOINCREMENT"] == true)
        _table.PrimaryKey.AutoIncrement = true;

      _dataType = (row.IsNull("DATA_TYPE") == false) ? row["DATA_TYPE"].ToString() : String.Empty;
      _columnName = row["COLUMN_NAME"].ToString();
      _origName = _columnName;

    [Browsable(false)]
    internal Table Table
    {
      get { return _table; }
    }

    internal void Committed()
    {
      _origName = ColumnName;
    }

    internal DataGridViewRow Parent
    {
      get { return _parent; }
      set 
      {
        _parent = value;
        _parent.Cells[0].Value = ColumnName;
        _parent.Cells[1].Value = DataType;
        _parent.Cells[2].Value = AllowNulls;
      }
    }

    internal void RefreshGrid()
    {
      if (_parent == null) return;
      _parent.DataGridView.Refresh();
    }

    internal void CellValueChanged(int rowIndex, int cellIndex)
    {
      if (_parent == null) return;
      if (rowIndex != _parent.Index) return;

      object value;

      if (_parent.Cells[cellIndex].IsInEditMode == true)
      {
        if (_parent.DataGridView.EditingControl != null)
          value = ((IDataGridViewEditingControl)_parent.DataGridView.EditingControl).EditingControlFormattedValue;
        else
          value = _parent.Cells[cellIndex].EditedFormattedValue;
      }
      else
        value = _parent.Cells[cellIndex].Value;

      if (value == null) value = String.Empty;

      switch (cellIndex)
      {
        case 0:
          ColumnName = value.ToString();
          break;
        case 1:
          DataType = value.ToString();
          break;
        case 2:
          AllowNulls = Convert.ToBoolean(value);
          break;
      }
    }
















    [DefaultValue("BINARY")]
    [Category("Constraints")]
    [Editor(typeof(CollationTypeEditor), typeof(UITypeEditor))]
    [Description("The collation sequence to use for the column.  This will affect comparison and equality tests against the column.")]
    public virtual string Collate
    {
      get { return _collate; }
      set
      {
        if (String.IsNullOrEmpty(value)) value = "BINARY";
        if (_collate != value)
        {
          _collate = value;
          
          if (_table.PrimaryKey.Columns.Count == 1 && String.Compare(ColumnName, _table.PrimaryKey.Columns[0].Column, StringComparison.OrdinalIgnoreCase) == 0)
            _table.PrimaryKey.Columns[0].Collate = value;

          _table._owner.MakeDirty();
        }
      }
    }

    [Category("Constraints")]
    [Description("The unique constraints of the column")]
    public virtual Unique Unique
    {
      get { return _unique; }
    }

    [Browsable(false)]
    public virtual string ColumnName
    {
      get { return _columnName; }
      set
      {
        if (value != _columnName)
        {
          _columnName = value;
          _table.MakeDirty();
        }
      }
    }

    [Browsable(false)]
    public virtual string OriginalName
    {
      get { return _origName; }
    }








    [DefaultValue(false)]
    [DisplayName("Allow Nulls")]
    [Category("Constraints")]
    [Description("Specifies whether or not the column will allow NULL values.")]
    public virtual bool AllowNulls
    {
      get { return _allowNulls; }
      set
      {
        if (value != _allowNulls)
        {
          _allowNulls = value;
          if (_parent == null) return;
          _parent.Cells[2].Value = _allowNulls;
          _table.MakeDirty();
        }
      }
    }

    [Browsable(false)]
    public virtual string DataType
    {
      get { return _dataType; }
      set
      {
        if (value != _dataType)
        {
          _dataType = value;
          _table.MakeDirty();
        }
      }
    }

    [DisplayName("Default Value")]
    [Category("Constraints")]
    [Description("The default value to populate in the column when an explicit value is not specified.")]
    public virtual string DefaultValue
    {
      get { return _defaultValue; }
      set { _defaultValue = value; }
    }

    internal void WriteSql(StringBuilder builder)

        if (_table.PrimaryKey.AutoIncrement == true)
          builder.Append(" AUTOINCREMENT");
      }

      if (AllowNulls == false)
        builder.Append(" NOT NULL");

      if (String.IsNullOrEmpty(Collate) == false && String.Compare(Collate, "BINARY", StringComparison.OrdinalIgnoreCase) != 0)
        builder.AppendFormat(" COLLATE {0}", Collate.ToUpperInvariant());

      if (Unique.Enabled == true && isprimary == false)
      {
        builder.Append(" UNIQUE");
        if (Unique.Conflict != ConflictEnum.Abort)
          builder.AppendFormat(" ON CONFLICT {0}", Unique.Conflict.ToString().ToUpperInvariant());





      }
    }
  }
}

/********************************************************
 * ADO.NET 2.0 Data Provider for SQLite Version 3.X
 * Written by Robert Simpson (robert@blackcastlesoft.com)
 * 
 * Released to the public domain, use at your own risk!
 ********************************************************/

namespace SQLite.Designer.Design
{
  using System;
  using System.Collections.Generic;
  using System.Collections;
  using System.Text;
  using System.ComponentModel;
  using System.Data;
  using System.Data.Common;
  using System.ComponentModel.Design;
  using System.Drawing.Design;
  using System.Windows.Forms;



  internal class ForeignKeyEditor : CollectionEditor
  {
    Table _table;
    CollectionEditor.CollectionForm _form;
    object[] _items;
    object[] _orig;
    int _count;

    internal ForeignKeyEditor(Table parent)
      : base(typeof(List<ForeignKey>))
    {
      _table = parent;
      _count = _table.ForeignKeys.Count;
    }

    protected override CollectionEditor.CollectionForm CreateCollectionForm()
    {
      _form = base.CreateCollectionForm();
      _form.Text = "Foreign Key Editor";
      foreach (Control c in _form.Controls[0].Controls)
      {
        PropertyGrid grid = c as PropertyGrid;
        if (grid != null)
        {
          grid.HelpVisible = true;
          break;
        }
      }
      _form.Width = (int)(_form.Width * 1.25);
      _form.Height = (int)(_form.Height * 1.25);

      return _form;
    }

    protected override object CreateInstance(Type itemType)
    {
      if (itemType == typeof(ForeignKey))
      {
        return new ForeignKey(null, _table, null);
      }
      throw new NotSupportedException();
    }

    protected override object[] GetItems(object editValue)
    {
      if (_items == null)
      {
        List<ForeignKey> items = editValue as List<ForeignKey>;
        _items = new object[items.Count];
        _orig = new object[items.Count];
        for (int n = 0; n < _items.Length; n++)
        {
          _items[n] = ((ICloneable)items[n]).Clone();
          _orig[n] = items[n];
        }
      }
      return _items;
    }

    protected override object SetItems(object editValue, object[] value)
    {
      bool dirty = false;
      if (_form.DialogResult == DialogResult.Cancel) value = _orig;

      if (editValue != null)
      {
        int length = this.GetItems(editValue).Length;
        int num2 = value.Length;
        if (!(editValue is IList))
        {
          return editValue;
        }
        IList list = (IList)editValue;
        list.Clear();
        for (int i = 0; i < value.Length; i++)
        {
          ForeignKey fkey = value[i] as ForeignKey;

          if (fkey != null && String.IsNullOrEmpty(fkey.From.Column) == false && String.IsNullOrEmpty(fkey.To.Catalog) == false &&
            String.IsNullOrEmpty(fkey.To.Table) == false && String.IsNullOrEmpty(fkey.To.Column) == false)
          {
            if (fkey.IsDirty) dirty = true;

            list.Add(value[i]);
          }
        }
        if ((dirty == true || list.Count != _count) && _form.DialogResult == DialogResult.OK)

        _table.MakeDirty();      
      }
      return editValue;





    }
  }

  internal class ForeignKeyItem : IHaveConnectionScope
  {
    private string _catalog;
    private string _table;

    public virtual string Column
    {
      get { return _column; }
    }

    protected void SetCatalog(string value)
    {
      if (_catalog != value)
      {
        _catalog = value;
        _fkey.MakeDirty();
      }
    }

    protected void SetTable(string value)
    {
      if (_table != value)
      {
        _table = value;
        _fkey.MakeDirty();
      }
    }

    protected void SetColumn(string value)
    {
      if (_column != value)
      {
        _column = value;
        _fkey.MakeDirty();
      }
    }
  }

  [TypeConverter(typeof(ExpandableObjectConverter))]
  internal class ForeignKeyFromItem : ForeignKeyItem
  {
    internal ForeignKeyFromItem(ForeignKey fkey, string column)
      : base(fkey, fkey._table.Catalog, fkey._table.Name, column)
    {
    }

    [Editor(typeof(ColumnsTypeEditor), typeof(UITypeEditor))]
    [Description("The primary (parent) column of the foreign key relationship")]
    public new string Column
    {
      get { return base.Column; }
      set { SetColumn(value); }
    }

    [Browsable(false)]

    internal ForeignKeyToItem(ForeignKey fkey, string catalog, string table, string column)
      : base(fkey, catalog, table, column)
    {
    }

    [Browsable(false)]
    [Editor(typeof(CatalogTypeEditor), typeof(UITypeEditor))]
    [Description("The database catalog (main, temp, or the name of an attached database) to which the foreign key refers.")]
    public new string Catalog
    {
      get
      {
        return base.Catalog;
      }
      set
      {
        SetCatalog(value);
      }
    }

    [DisplayName("Base Table")]
    [Editor(typeof(TablesTypeEditor), typeof(UITypeEditor))]
    [Description("The child table to which the foreign key refers.")]
    public new string Table
    {
      get { return base.Table; }
      set { SetTable(value); }
    }

    [Editor(typeof(ColumnsTypeEditor), typeof(UITypeEditor))]
    [Description("The child column to which the foreign key refers.")]
    public new string Column
    {
      get { return base.Column; }
      set { SetColumn(value); }
    }
  }

  [DefaultProperty("From")]
  internal class ForeignKey : IHaveConnection, ICloneable
  {
    internal Table _table;
    internal ForeignKeyFromItem _from;
    internal ForeignKeyToItem _to;
    internal string _name;
    private bool _dirty = false;

    private ForeignKey(ForeignKey source)
    {
      _table = source._table;
      _from = new ForeignKeyFromItem(this, source._from.Column);
      _to = new ForeignKeyToItem(this, source._to.Catalog, source._to.Table, source._to.Column);
      _name = source._name;
      _dirty = source._dirty;
    }

    internal void MakeDirty()
    {
      _dirty = true;
    }

    [Browsable(false)]
    internal bool IsDirty
    {
      get { return _dirty; }
    }

    internal void ClearDirty()
    {
      _dirty = false;
    }

    internal ForeignKey(DbConnection cnn, Table table, DataRow row)
    {
      _table = table;
      if (row != null)
      {

      {
        builder.AppendFormat("CONSTRAINT [{0}] FOREIGN KEY ([{1}]) REFERENCES [{3}] ([{4}])", Name, _from.Column, _to.Catalog, _to.Table, _to.Column);
      }
    }

    [ParenthesizePropertyName(true)]
    [Category("Identity")]
    [Description("The name of the foreign key.")]
    public string Name
    {
      get
      {
        if (String.IsNullOrEmpty(_name) == false) return _name;

        return String.Format("FK_{0}_{1}_{2}_{3}", _from.Table, _from.Column, _to.Table, _to.Column);
      }
      set
      {
        if (_name != value)
        {
          _name = value;
          MakeDirty();
        }
      }
    }

    #region IHaveConnection Members

    public DbConnection GetConnection()
    {
      return ((IHaveConnection)_table).GetConnection();
    }

    #endregion

    [DisplayName("Primary/Unique Key")]
    [Category("Source")]
    [Description("The source (parent) column in the current table that is to be the unique value of the foreign key.")]
    public ForeignKeyFromItem From
    {
      get { return _from; }
    }

    [DisplayName("Foreign Key")]
    [Category("Target")]
    [Description("The child table and column to which the specified parent column is related.")]
    public ForeignKeyToItem To
    {
      get { return _to; }
    }

    #region ICloneable Members

/********************************************************
 * ADO.NET 2.0 Data Provider for SQLite Version 3.X
 * Written by Robert Simpson (robert@blackcastlesoft.com)
 * 
 * Released to the public domain, use at your own risk!
 ********************************************************/

namespace SQLite.Designer.Design
{
  using System;
  using System.Collections.Generic;
  using System.Collections;
  using System.Text;
  using System.ComponentModel;
  using System.Data;
  using System.Data.Common;
  using System.ComponentModel.Design;
  using System.Drawing.Design;
  using System.Windows.Forms;



  internal class IndexEditor : CollectionEditor
  {
    Table _table;
    CollectionEditor.CollectionForm _form;
    object[] _items = null;
    object[] _orig;
    int _count;

    internal IndexEditor(Table parent)
      : base(typeof(List<Index>))
    {
      _table = parent;
    }




















    protected override object[] GetItems(object editValue)
    {
      if (_items == null)
      {
        List<Index> value = editValue as List<Index>;

        int extra = (_table.PrimaryKey.Columns.Count > 0) ? 1 : 0;

        _items = new object[value.Count + extra];
        _orig = new object[_items.Length];
        for (int n = extra; n < _items.Length; n++)
        {
          _items[n] = ((ICloneable)value[n - extra]).Clone();
          _orig[n] = value[n - extra];
        }

        if (extra > 0)
        {
          _items[0] = ((ICloneable)_table.PrimaryKey).Clone();
          _orig[0] = _table.PrimaryKey;
        }

        _count = _items.Length;
      }
      return _items;
    }

    protected override CollectionEditor.CollectionForm CreateCollectionForm()
    {
      _form = base.CreateCollectionForm();
      _form.Text = "Index Editor";

      /* Doing this because I can't figure out how to get the Columns collection editor to notify this editor when a column of an index is updated.
         This forces the collection editor form to be "dirty" which calls SetItems() when you hit OK or cancel.  Otherwise, if you
         change a column around and hit OK, then hit OK on this editor, it won't be dirty and won't update. */
      try
      {
        _form.GetType().InvokeMember("dirty", System.Reflection.BindingFlags.NonPublic | System.Reflection.BindingFlags.Instance | System.Reflection.BindingFlags.SetField, null, _form, new object[] { true });
      }
      catch
      {
      }

      foreach (Control c in _form.Controls[0].Controls)
      {
        PropertyGrid grid = c as PropertyGrid;
        if (grid != null)
        {
          grid.HelpVisible = true;
          break;
        }
      }
      _form.Width = (int)(_form.Width * 1.25);
      _form.Height = (int)(_form.Height * 1.25);

      return _form;
    }

    protected override object CreateInstance(Type itemType)
    {
      if (itemType == typeof(Index))
      {
        return new Index(null, _table, null);
      }
      throw new NotSupportedException();
    }

    protected override bool CanRemoveInstance(object value)
    {
      return !(value is PrimaryKey);
    }

    protected override object SetItems(object editValue, object[] value)
    {
      bool dirty = false;
      int count = 0;

      if (_form.DialogResult == DialogResult.Cancel)
        value = _orig;

      if (editValue != null)
      {
        int length = this.GetItems(editValue).Length;
        int num2 = value.Length;
        if (!(editValue is IList))
        {
          return editValue;
        }
        IList list = (IList)editValue;
        list.Clear();
        for (int i = 0; i < value.Length; i++)
        {
          Index idx = value[i] as Index;

          if (idx is PrimaryKey)
          {
            _table.PrimaryKey = (PrimaryKey)idx;
            if (idx.IsDirty) dirty = true;
            count++;
          }
          else
          {
            if (idx != null && idx.Columns.Count > 0)
            {
              idx.Name = idx.Name;
              list.Add(idx);
              if (idx.IsDirty) dirty = true;
              count++;
            }
          }
        }
      }

      if ((dirty == true || count != _count) && _form.DialogResult == DialogResult.OK)
        _table._owner.MakeDirty();

      return editValue;
    }
  }

  internal class IndexColumnEditor : CollectionEditor
  {
    Index _index;

    object[] _items;
    object[] _orig;
    int _count;
    CollectionEditor.CollectionForm _form;

    public IndexColumnEditor() : base(typeof(List<IndexColumn>))
    {
    }

    protected override CollectionEditor.CollectionForm CreateCollectionForm()
    {
      _form = base.CreateCollectionForm();
      _form.Text = "Index Columns Editor";
      foreach (Control c in _form.Controls[0].Controls)
      {
        PropertyGrid grid = c as PropertyGrid;
        if (grid != null)
        {
          grid.HelpVisible = true;
          break;
        }
      }
      _form.Width = (int)(_form.Width * 1.25);
      _form.Height = (int)(_form.Height * 1.25);
      return _form;
    }

    public override object EditValue(ITypeDescriptorContext context, IServiceProvider provider, object value)
    {
      _index = context.Instance as Index;
      _items = null;
      _count = 0;
      return base.EditValue(context, provider, value);
    }

    protected override object CreateInstance(Type itemType)
    {
      if (itemType == typeof(IndexColumn))
      {
        return new IndexColumn(_index, null);
      }
      throw new NotSupportedException();
    }






    protected override object[] GetItems(object editValue)
    {
      if (_items == null)
      {
        List<IndexColumn> value = editValue as List<IndexColumn>;
        _items = new object[value.Count];
        _orig = new object[value.Count];
        for (int n = 0; n < _items.Length; n++)
        {
          _items[n] = ((ICloneable)value[n]).Clone();
          _orig[n] = value[n];
        }

        _count = _items.Length;
      }
      return _items;
    }

    protected override object SetItems(object editValue, object[] value)
    {
      if (_form.DialogResult == DialogResult.Cancel)
        value = _orig;

      if (editValue != null)
      {
        int length = this.GetItems(editValue).Length;
        int num2 = value.Length;
        if (!(editValue is IList))
        {
          return editValue;
        }
        IList list = (IList)editValue;
        list.Clear();
        for (int i = 0; i < value.Length; i++)
        {
          IndexColumn idx = value[i] as IndexColumn;

          if (idx != null && String.IsNullOrEmpty(idx.Column) == false)
          {
            list.Add(value[i]);
          }
        }
      }

      if ((_index.IsDirty || _index.Columns.Count != _count) && _form.DialogResult == DialogResult.OK)
      {
        if (_index.Columns.Count > 0 && String.IsNullOrEmpty(_index._name) == true)
          _index.Name = _index.Name;
      }



      return editValue;
    }
  }

  internal class IndexTypeConverter : TypeConverter
  {
    public override bool CanConvertFrom(ITypeDescriptorContext context, Type sourceType)

        string separator = "";
        foreach (IndexColumn c in (List<IndexColumn>)value)
        {
          builder.AppendFormat("{0}[{1}]", separator, c.Column);
          if (c.SortMode != ColumnSortMode.Ascending)
            builder.Append(" DESC");
          if (c.Collate != "BINARY")
            builder.AppendFormat(" COLLATE {0}", c.Collate.ToUpperInvariant());

          separator = ", ";
        }
        return builder.ToString();
      }
      else
        return base.ConvertTo(context, culture, value, destinationType);
    }
  }

  internal enum ColumnSortMode
  {
    Ascending = 0,
    Descending = 1
  }

  [DefaultProperty("Column")]
  internal class IndexColumn : IHaveConnectionScope, ICloneable
  {
    internal Index _parent;
    private string _column;
    private ColumnSortMode _mode = ColumnSortMode.Ascending;
    private string _collate = "BINARY";

    [Editor(typeof(ColumnsTypeEditor), typeof(UITypeEditor))]
    [DisplayName("Base Column")]
    [Category("Source")]
    [Description("The column name to be included in the index.")]
    [NotifyParentProperty(true)]
    [RefreshProperties(RefreshProperties.All)]
    public string Column
    {
      get { return _column; }
      set
      {
        if (_column != value)
        {
          _column = value;
          _parent.MakeDirty();
        }
      }
    }

    [DefaultValue(ColumnSortMode.Ascending)]
    [Category("Constraints")]
    [Description("Specifies what order to sort the column in.  Descending indexes are not supported when using the SQLite legacy file format.")]
    [NotifyParentProperty(true)]
    [RefreshProperties(RefreshProperties.All)]
    public ColumnSortMode SortMode
    {
      get { return _mode; }
      set
      {
        if (value != _mode)
        {
          _mode = value;
          _parent.MakeDirty();
        }
      }
    }

    [DefaultValue("BINARY")]
    [Category("Constraints")]
    [Editor(typeof(CollationTypeEditor), typeof(UITypeEditor))]
    [Description("The collation sequence to use to generate the index for the specified column.")]
    [NotifyParentProperty(true)]
    [RefreshProperties(RefreshProperties.All)]
    public string Collate
    {
      get { return _collate; }
      set
      {
        if (String.IsNullOrEmpty(value)) value = "BINARY";

        if (value != _collate)
        {
          _collate = value;
          if (_parent is PrimaryKey)
          {
            PrimaryKey pk = _parent as PrimaryKey;
            if (pk.Columns.Count == 1)
            {
              foreach (Column c in pk.Table.Columns)
              {
                if (string.Compare(c.ColumnName, Column, StringComparison.OrdinalIgnoreCase) == 0)
                {
                  c.Collate = value;
                  break;
                }
              }
            }
          }
          _parent.MakeDirty();
        }
      }
    }

    public override string ToString()
    {
      if (String.IsNullOrEmpty(_column) == true) return "(none)";
      return _column;

    }

    internal IndexColumn(Index parent, DataRow row)
    {
      _parent = parent;
      if (row != null)
      {
        _column = row["COLUMN_NAME"].ToString();
        if (row.IsNull("SORT_MODE") == false && (string)row["SORT_MODE"] != "ASC")
          _mode = ColumnSortMode.Descending;

        if (row.IsNull("COLLATION_NAME") == false)
          _collate = row["COLLATION_NAME"].ToString().ToUpperInvariant();
      }
    }

    public object Clone()
    {
      return new IndexColumn(this);
    }

    private Table _table;
    internal string _name = null;
    private bool _unique;
    private List<IndexColumn> _columns = new List<IndexColumn>();
    private string _definition;
    private bool _calcname;
    internal ConflictEnum _conflict = ConflictEnum.Abort;
    bool _dirty = false;

    protected Index(Index source)
    {
      _table = source._table;
      _name = source._name;
      _unique = source._unique;

      _definition = source._definition;
      _conflict = source._conflict;
      _dirty = source._dirty;

      foreach (IndexColumn c in source._columns)
      {
        IndexColumn copy = ((ICloneable)c).Clone() as IndexColumn;
        copy._parent = this;
        _columns.Add(copy);
      }
    }

    internal Index(DbConnection cnn, Table table, DataRow index)
    {
      _table = table;
      if (index != null)
      {
        _name = index["INDEX_NAME"].ToString();
        _unique = (bool)index["UNIQUE"];
        _definition = index["INDEX_DEFINITION"].ToString();

        using (DataTable tbl = cnn.GetSchema("IndexColumns", new string[] { table.Catalog, null, table.Name, Name }))
        {
          foreach (DataRow row in tbl.Rows)
          {
            _columns.Add(new IndexColumn(this, row));








          }
        }
      }
    }

    [DisplayName("Index Type")]
    [Category("Storage")]
    [Description("Specifies whether this is an index or a primary key.")]
    public virtual IndexTypeEnum IndexType
    {
      get { return IndexTypeEnum.Index; }
    }

    #region IHaveConnection Members

    internal virtual void WriteSql(StringBuilder builder)
    {
      string separator = "";
      builder.AppendFormat("CREATE {0}INDEX [{1}].[{2}] ON [{3}] (", (_unique == true) ? "UNIQUE " : "", _table.Catalog, Name, _table.Name);
      foreach (IndexColumn c in Columns)
      {
        builder.AppendFormat("{0}[{1}]", separator, c.Column);
        
        if (c.SortMode != ColumnSortMode.Ascending)
          builder.Append(" DESC");

        if (String.IsNullOrEmpty(c.Collate) && String.Compare(c.Collate,"BINARY", StringComparison.OrdinalIgnoreCase) != 0)
          builder.AppendFormat(" COLLATE {0}", c.Collate.ToUpperInvariant());

        separator = ", ";
      }
      builder.AppendFormat(");");
    }

    [Browsable(false)]
    internal Table Table
    {
      get { return _table; }
    }

    [Browsable(false)]
    public string OriginalSql
    {
      get { return _definition; }
    }

    internal void MakeDirty()
    {
      _dirty = true;
    }

    [Browsable(false)]
    internal bool IsDirty
    {
      get { return _dirty; }
    }

    internal void ClearDirty()
    {
      _dirty = false;
    }

    [DefaultValue(false)]
    [Description("When set to true, the combination of column(s) of the index must be a unique value.")]
    public virtual bool Unique
    {
      get { return _unique; }
      set
      {
        if (value != _unique)
        {
          _unique = value;
          MakeDirty();
        }
      }
    }

    [Browsable(false)]
    protected virtual string NamePrefix
    {
      get { return "IX"; }
    }

    [Browsable(false)]
    protected virtual string NewName
    {
      get { return "NewIndex"; }
    }

    [ParenthesizePropertyName(true)]
    [RefreshProperties(RefreshProperties.All)]
    [Category("Identity")]
    [Description("The name of the index.")]
    public virtual string Name
    {
      get
      {
        if (String.IsNullOrEmpty(_name))
        {
          if (_calcname == true) return GetHashCode().ToString();

            }
          }
          _calcname = false;
          return proposed;
        }
        return _name;
      }
      set
      {
        if (value != _name)
        {
          _name = value;
          MakeDirty();
        }
      }
    }

    [TypeConverter(typeof(IndexTypeConverter))]
    [Editor(typeof(IndexColumnEditor), typeof(UITypeEditor))]
    [RefreshProperties(RefreshProperties.All)]
    [Category("Source")]
    [Description("The column(s) to be indexed.")]
    [NotifyParentProperty(true)]
    public List<IndexColumn> Columns
    {
      get { return _columns; }
    }

    #region ICloneable Members

    {
      return UITypeEditorEditStyle.DropDown;
    }

    override public object EditValue(ITypeDescriptorContext ctx, IServiceProvider provider, object value)
    {
      Index idx = ctx.Instance as Index;
      Trigger trig = ctx.Instance as Trigger;
      ViewTableBase parent = null;

      if (idx != null) parent = idx.Table;
      else if (trig != null) parent = trig.ViewTableBase;

      // initialize editor service
      _edSvc = (System.Windows.Forms.Design.IWindowsFormsEditorService)provider.GetService(typeof(System.Windows.Forms.Design.IWindowsFormsEditorService));
      if (_edSvc == null)
        return value;

      if (value == null) value = String.Empty;
      if (String.IsNullOrEmpty(value.ToString()) == true) value = String.Empty;

      string[] values = value.ToString().Split(',');
      
      // populate the list
      _list.Items.Clear();
      DataTable tbl = null;

      try
      {
        string prefix = "";
        tbl = parent.GetConnection().GetSchema("Columns", new string[] { parent.Catalog, null, parent.Name });
        if (tbl.Rows.Count == 0)
        {
          tbl.Dispose();
          tbl = null;
          prefix = "VIEW_";
          tbl = parent.GetConnection().GetSchema("ViewColumns", new string[] { parent.Catalog, null, parent.Name });
        }
        foreach (DataRow item in tbl.Rows)
        {
          // add this item with the proper check state
          CheckState check = CheckState.Unchecked;
          for (int n = 0; n < values.Length; n++)
          {
            if (values[n].Trim() == String.Format("[{0}]", item[prefix + "COLUMN_NAME"].ToString()))
            {
              check = CheckState.Checked;
              break;
            }
          }
          _list.Items.Add(item[prefix + "COLUMN_NAME"].ToString(), check);
        }
      }
      finally
      {
        if (tbl != null) tbl.Dispose();
      }
      _list.Height = Math.Min(300, (_list.Items.Count + 1) * _list.Font.Height);

      // show the list
      _cancel = false;
      _edSvc.DropDownControl(_list);

      // build return value from checked items on the list

/********************************************************
 * ADO.NET 2.0 Data Provider for SQLite Version 3.X
 * Written by Robert Simpson (robert@blackcastlesoft.com)

 * 
 * Released to the public domain, use at your own risk!

 ********************************************************/

namespace SQLite.Designer.Design
{
  using System;
  using System.Collections.Generic;
  using System.Text;
  using System.ComponentModel;
  using System.Data;
  using System.Data.Common;

  internal class PrimaryKey : Index, ICloneable
  {
    private bool _autoincrement;

    internal PrimaryKey(DbConnection cnn, Table table, DataRow row)
      : base(cnn, table, row)
    {

      {
        base.Unique = true;
      }
    }

    [DefaultValue(ConflictEnum.Abort)]
    [DisplayName("On Conflict")]
    [Category("Constraints")]
    [Description("Specifies what action to take when the primary key constraint is violated.")]
    public ConflictEnum Conflict
    {
      get { return _conflict; }
      set
      {
        if (value != _conflict)
        {
          _conflict = value;
          MakeDirty();
        }
      }
    }

    [DefaultValue(false)]
    [Category("Constraints")]
    [Description("Can only be enabled for a single column primary key of type INTEGER.  When set, the primary key is guaranteed to increment in sequence, and no previously deleted or uncommitted values will ever be used.")]
    public bool AutoIncrement
    {
      get
      {
        if (Columns.Count > 1) return false;
        if (Columns.Count == 1 && Columns[0].SortMode != ColumnSortMode.Ascending) return false;
        return _autoincrement;
      }
      set
      {
        if (value != _autoincrement)
        {
          _autoincrement = value;
          MakeDirty();
        }
      }
    }

    #region ICloneable Members

    object ICloneable.Clone()
    {
      return new PrimaryKey(this);
    }

    #endregion
  }
}

/********************************************************
 * ADO.NET 2.0 Data Provider for SQLite Version 3.X
 * Written by Robert Simpson (robert@blackcastlesoft.com)
 * 
 * Released to the public domain, use at your own risk!
 ********************************************************/

namespace SQLite.Designer.Design
{
  using System;
  using System.Collections.Generic;
  using System.Text;

  internal static class SimpleTokenizer
  {
    public struct StringParts
    {
      internal string value;
      internal int position;
      internal string quote;
      internal bool sep;
      internal int depth;
      internal string keyword;
      internal char sepchar;

      public override string ToString()
      {
        return String.Format("{0} {1} at {2} {3} depth {4}", value, quote, position, sep == true ? "(sep)" : "", depth);
      }
    }

    public static StringParts[] BreakString(string source)
    {
      char[] opens = new char[] { '\"', '[', '\'', '(', ')', ',', ' ', ';', '\r', '\n', '\t' };
      char[] opens2 = new char[] { '\"', '[', '\'', '(', ')', ',', ' ', ';', '\r', '\n', '\t', '.' };
      char[] closes = new char[] { '\"', ']', '\'', };
      string sep = ";,";
      string opensstr = "\"['";

      if (String.IsNullOrEmpty(source) == true) return new StringParts[0];

      int n = 0;
      int x;
      int depth = 0;
      List<StringParts> ls = new List<StringParts>();
      int startat = 0;

      while (source.Length > 0)
      {
        if (source.Length > 1 && source[0] == '-' && source[1] == '-')
        {
          StringParts tok = new StringParts();
          tok.position = startat;
          x = source.IndexOf('\n');
          if (x == -1) tok.value = source;
          else tok.value = source.Substring(0, x + 1);

          //ls.Add(tok);
          source = source.Substring(tok.value.Length);
          startat += tok.value.Length;
          continue;
        }
        else if (source.Length > 1 && source[0] == '/' && source[1] == '*')
        {
          StringParts tok = new StringParts();
          tok.position = startat;
          x = source.IndexOf("*/");
          if (x == -1) tok.value = source;
          else tok.value = source.Substring(0, x + 2);

          //ls.Add(tok);
          source = source.Substring(tok.value.Length);
          startat += tok.value.Length;
          continue;
        }
        int comment = source.IndexOf("--", n);
        if (comment == -1) comment = source.IndexOf("/*", n);

        if (n > 0)
          n = source.IndexOfAny(opens2, n);
        else
          n = source.IndexOfAny(opens, n);

        if (comment > -1 && (n == -1 || comment < n))
          n = comment;

        if (n == -1) break;

        x = opensstr.IndexOf(source[n]);
        if (x != -1)
        {
          while (n != -1)
          {
            n = source.IndexOf(closes[x], n + 1);
            if (n == -1)
              break;

            if (n < source.Length - 1 && source[n + 1] == source[n])
            {
              startat++;
              source = source.Remove(n, 1);
            }
            else
            {
              n++;
              break;
            }
          }
          if (n == -1)
            break;
        }
        else
        {
          StringParts tok = new StringParts();

          int y = sep.IndexOf(source[n]);
          tok.sep = (y != -1);
          tok.sepchar = (y != -1) ? sep[y] : '\0';

          if (source[n] == '(') depth++;
          tok.depth = depth;
          if (source[n] == ')') depth--;

          tok.value = source.Substring(0, n);
          tok.position = startat;

          if (tok.value.Length > 1)
          {
            x = opensstr.IndexOf(tok.value[0]);
            if (x != -1 && tok.value[tok.value.Length - 1] == closes[x])
            {
              tok.quote = String.Format("{0}{1}", tok.value[0], tok.value[tok.value.Length - 1]);
              tok.value = tok.value.Substring(1, tok.value.Length - 2);
            }
            else
              tok.keyword = tok.value.ToUpperInvariant();
          }

          if (source.Length - n > 1 && ((source[n] == '-' && source[n + 1] == '-') || source[n] == '/' && source[n + 1] == '*'))
          {
            startat += n;
            source = source.Substring(n);
          }
          else
          {
            startat += (n + 1);
            source = source.Substring(n + 1);
          }
          if (tok.value.Length > 0)
            ls.Add(tok);
          else if (ls.Count > 0 && tok.sep)
          {
            StringParts prev = ls[ls.Count - 1];
            ls.RemoveAt(ls.Count - 1);
            prev.sep = tok.sep;
            prev.sepchar = tok.sepchar;
            ls.Add(prev);
          }
          n = 0;
        }
      }

      if (source.Length > 0)
      {
        StringParts tok = new StringParts();

        tok.value = source.Trim();
        tok.position = startat;

        if (tok.value.Length > 1)
        {
          x = opensstr.IndexOf(tok.value[0]);
          if (x != -1 && tok.value[tok.value.Length - 1] == closes[x])
          {
            tok.quote = String.Format("{0}{1}", tok.value[0], tok.value[tok.value.Length - 1]);
            tok.value = tok.value.Substring(1, tok.value.Length - 2);
          }
          else
            tok.keyword = tok.value.ToUpperInvariant();
        }
        if (tok.value.Length > 0) ls.Add(tok);
      }

      StringParts[] ar = new StringParts[ls.Count];
      ls.CopyTo(ar, 0);

      return ar;
    }
  }
}

/********************************************************
 * ADO.NET 2.0 Data Provider for SQLite Version 3.X
 * Written by Robert Simpson (robert@blackcastlesoft.com)
 * 
 * Released to the public domain, use at your own risk!
 ********************************************************/

namespace SQLite.Designer.Design
{
  using System;
  using System.Data.Common;
  using System.ComponentModel.Design;
  using System.ComponentModel;
  using System.Drawing.Design;
  using System.Collections.Generic;
  using System.Data;
  using System.Text;
  using SQLite.Designer.Editors;

  internal abstract class ViewTableBase: IHaveConnection
  {
    public abstract string Name { get; set; }
    public abstract string Catalog { get; }
    public abstract object Triggers { get; }
    public abstract void MakeDirty();
    public abstract DbConnection GetConnection();
  }

  internal class Table : ViewTableBase, ICustomTypeDescriptor
  {
    private string _name;
    private string _oldname;
    private string _catalog;
    private List<Column> _columns = new List<Column>();
    private bool _exists = false;
    private bool _hascheck = false;
    private string _origSql = String.Empty;
    private List<Index> _indexes = new List<Index>();
    private List<Index> _oldindexes = new List<Index>();
    private List<ForeignKey> _fkeys = new List<ForeignKey>();
    private List<ForeignKey> _oldfkeys = new List<ForeignKey>();
    private List<string> _check = new List<string>();
    private List<Trigger> _triggers = new List<Trigger>();
    private List<Trigger> _oldtriggers = new List<Trigger>();
    private PrimaryKey _key;
    internal TableDesignerDoc _owner;
    internal DbConnection _connection;

    internal Table(string tableName, DbConnection connection, TableDesignerDoc owner)
    {
      _owner = owner;

      {
        foreach (DataRow row in tbl.Rows)
        {
          _columns.Add(new Column(row, this));
        }
      }
    }

    public override void MakeDirty()
    {
      _owner.MakeDirty();
    }

    private void ReloadDefinition()
    {
      using (DataTable tbl = _connection.GetSchema("Tables", new string[] { Catalog, null, Name }))
      {
        if (tbl.Rows.Count > 0)
        {

          else if (_key == null)
          {
            _key = new PrimaryKey(_connection, this, row);
          }
        }
      }

      _check.Clear();
      StringBuilder builder = new StringBuilder();
      SimpleTokenizer.StringParts[] arr = SimpleTokenizer.BreakString(_origSql);
      for (int n = 0; n < arr.Length - 3; n++)
      {
        if (arr[n].keyword == "CONSTRAINT")
        {
          builder.Length = 0;
          int x;
          for (x = 1; x < 3; x++)
          {
            if (arr[n + x].keyword == "CHECK")
              break;
          }
          if (x == 3)
          {
            n += 2;
            continue;
          }
          x += n + 1;
          int depth = arr[n].depth;
          int basedepth = arr[x].depth;
          for (; x < arr.Length; x++)
          {
            if (arr[x].depth < basedepth)
              break;

            if (builder.Length > 0)
              builder.Append(" ");

            while (depth < arr[x].depth)
            {
              builder.Append("(");
              depth++;
            }
            while (depth > arr[x].depth)
            {
              builder.Append(")");
              depth--;
            }

            if (String.IsNullOrEmpty(arr[x].quote) == false)
              builder.Append(arr[x].quote[0]);
            builder.Append(arr[x].value);
            if (String.IsNullOrEmpty(arr[x].quote) == false)
              builder.Append(arr[x].quote[1]);

            if (arr[x].sep == true) break;
          }
          while (depth > arr[n].depth)
          {
            builder.Append(")");
            depth--;
          }
          n = x;
          _check.Add(builder.ToString());
        }
      }

      builder.Length = 0;
      builder.Append(_origSql);

      builder.AppendLine(";");
      foreach (Index idx in _oldindexes)
      {
        builder.AppendFormat("{0};\r\n", idx.OriginalSql);
      }

      _triggers.Clear();
      _oldtriggers.Clear();

      using (DataTable tbl = _connection.GetSchema("Triggers", new string[] { Catalog, null, Name }))
      {
        foreach (DataRow row in tbl.Rows)
        {
          Trigger t = new Trigger(this, row);
          _triggers.Add(t);
          _oldtriggers.Add(((ICloneable)t).Clone() as Trigger);

          builder.AppendFormat("{0};\r\n", t.OriginalSql);
        }
      }

      _origSql = builder.ToString();
    }

    internal void Committed()
    {
      _exists = true;
      ReloadDefinition();

      foreach (Column c in Columns)
        c.Committed();

      foreach (ForeignKey key in ForeignKeys)
        key.ClearDirty();

      foreach (Index idx in Indexes)
        idx.ClearDirty();

      if (PrimaryKey != null)
        PrimaryKey.ClearDirty();
    }

    [Browsable(false)]
    public List<Index> Indexes
    {
      get { return _indexes; }
    }

    }

    [Browsable(false)]
    public List<ForeignKey> ForeignKeys
    {
      get { return _fkeys; }
    }

    [Browsable(false)]
    public List<string> Check
    {
      get { return _check; }
    }

    [Browsable(false)]
    public override object Triggers
    {
      get { return _triggers; }
    }

    [Browsable(false)]
    public string OriginalSql
    {
      get { return _origSql; }
    }

    [Browsable(false)]
    public bool HasCheck
    {
      get { return _hascheck; }
    }

    [Category("Storage")]
    [RefreshProperties(RefreshProperties.All)]
    [ParenthesizePropertyName(true)]
    public override string Name
    {
      get { return _name; }
      set
      {
        if (_name != value)
        {
          _name = value;

      return String.Format("[{0}].[{1}]", Catalog, Name);
    }

    [Category("Storage")]
    [Editor(typeof(CatalogTypeEditor), typeof(UITypeEditor))]
    [DefaultValue("main")]
    [RefreshProperties(RefreshProperties.All)]
    public override string Catalog
    {
      get { return _catalog; }










    }






    [Category("Storage")]
    public string Database
    {
      get { return _connection.DataSource; }
    }

    [Browsable(false)]

      string altName = null;

      if (_exists)
      {
        Guid g = Guid.NewGuid();
        altName = String.Format("{0}_{1}", Name, g.ToString("N"));

        if (_oldindexes.Count > 0)
        {
          builder.Append("-- Drop previous indexes on the table\r\n");
          foreach (Index idx in _oldindexes)
          {
            builder.AppendFormat("DROP INDEX [{0}].[{1}];\r\n", _catalog, idx.Name);
          }
          builder.AppendLine();
        }

        if (_oldtriggers.Count > 0)
        {
          builder.Append("-- Drop previous triggers on the table\r\n");
          foreach (Trigger trig in _oldtriggers)
          {
            builder.AppendFormat("DROP TRIGGER [{0}].[{1}];\r\n", _catalog, trig.Name);
          }
          builder.AppendLine();
        }

        builder.Append("-- Rename the old table\r\n");
        builder.AppendFormat("ALTER TABLE [{0}].[{1}] RENAME TO [{2}];\r\n\r\n", _catalog, _oldname, altName);
      }

      builder.Append("-- Create the new table\r\n");
      builder.AppendFormat("CREATE TABLE [{0}].[{1}] (\r\n", _catalog, Name);
      string separator = "    ";

      foreach (Column c in Columns)
      {
        if (String.IsNullOrEmpty(c.ColumnName) == false)
        {
          builder.Append(separator);
          c.WriteSql(builder);
          separator = ",\r\n    ";
        }
      }

      if (_key.Columns.Count > 1)
      {
        string innersep = "";
        builder.AppendFormat("{0}CONSTRAINT [PK_{1}] PRIMARY KEY (", separator, Name);
        foreach (IndexColumn c in _key.Columns)
        {
          builder.AppendFormat("{0}[{1}]", innersep, c.Column);
          if (String.IsNullOrEmpty(c.Collate) == false && String.Compare(c.Collate, "BINARY", StringComparison.OrdinalIgnoreCase) != 0)
            builder.AppendFormat(" COLLATE {0}", c.Collate.ToUpperInvariant());

          if (c.SortMode != ColumnSortMode.Ascending)
            builder.AppendFormat(" DESC");

          innersep = ", ";
        }
        builder.Append(")");

        if (_key.Conflict != ConflictEnum.Abort)
          builder.AppendFormat(" ON CONFLICT {0}", _key.Conflict.ToString().ToUpperInvariant());
      }

      for (int n = 0; n < Check.Count; n++)
      {
        string check = Check[n];

        if (String.IsNullOrEmpty(check) == true) continue;
        SimpleTokenizer.StringParts[] arr = SimpleTokenizer.BreakString(check);
        for (int x = 0; x < arr.Length; x++)
        {
          if (arr[x].depth == 0)
          {
            check = String.Format("({0})", check);
            break;
          }
        }
        builder.Append(separator);
        builder.AppendFormat("CONSTRAINT [CK_{0}_{1}] CHECK {2}", Name, n + 1, check);
      }

      foreach (ForeignKey fkey in ForeignKeys)
      {
        builder.Append(separator);
        fkey.WriteSql(builder);
      }

      builder.Append("\r\n);\r\n");

      // Rebuilding an existing table
      if (altName != null)
      {
        separator = "";
        builder.Append("\r\n-- Copy the contents of the old table into the new table\r\n");
        builder.AppendFormat("INSERT INTO [{0}].[{1}] (", _catalog, Name);
        foreach (Column c in Columns)
        {
          if (String.IsNullOrEmpty(c.OriginalName) == false)
          {
            builder.AppendFormat("{1}[{0}]", c.ColumnName, separator);
            separator = ", ";
          }
        }
        builder.Append(")\r\n  SELECT ");
        separator = "";
        foreach (Column c in Columns)
        {
          if (String.IsNullOrEmpty(c.OriginalName) == false)
          {
            builder.AppendFormat("{1}[{0}]", c.OriginalName, separator);
            separator = ", ";
          }
        }
        builder.AppendFormat("\r\n  FROM [{0}].[{1}];\r\n\r\n", _catalog, altName);

        builder.Append("-- Drop the old table\r\n");
        builder.AppendFormat("DROP TABLE [{0}].[{1}];\r\n", _catalog, altName);
      }

      separator = "\r\n";
      if (_indexes.Count > 0)
      {
        builder.Append("\r\n-- Create the new indexes");
        foreach (Index idx in _indexes)
        {
          builder.Append(separator);
          idx.WriteSql(builder);
        }
        builder.AppendLine();
      }

      if (_triggers.Count > 0)
      {
        builder.Append("\r\n-- Create the new triggers");
        foreach (Trigger trig in _triggers)
        {
          builder.Append(separator);
          trig.WriteSql(builder);
          separator = "\r\n";
        }
        builder.AppendLine();
      }

      return builder.ToString();
    }



    public override DbConnection GetConnection()
    {
      return _connection;
    }



    #region ICustomTypeDescriptor Members

    AttributeCollection ICustomTypeDescriptor.GetAttributes()
    {
      return TypeDescriptor.GetAttributes(GetType());
    }

  internal interface IHaveConnectionScope : IHaveConnection
  {
    [Browsable(false)]
    string CatalogScope { get; }
    [Browsable(false)]
    string TableScope { get; }
  }

  internal class CollationTypeEditor : ObjectSelectorEditor
  {
    public override UITypeEditorEditStyle GetEditStyle(ITypeDescriptorContext context)
    {
      return UITypeEditorEditStyle.DropDown;
    }

    protected override void FillTreeWithData(Selector selector, ITypeDescriptorContext context, IServiceProvider provider)
    {
      base.FillTreeWithData(selector, context, provider);
      selector.AddNode("BINARY", "BINARY", null);
      selector.AddNode("NOCASE", "NOCASE", null);
    }
  }

  internal class CatalogTypeEditor : ObjectSelectorEditor
  {
    public override UITypeEditorEditStyle GetEditStyle(ITypeDescriptorContext context)
    {
      return UITypeEditorEditStyle.DropDown;
    }

/********************************************************
 * ADO.NET 2.0 Data Provider for SQLite Version 3.X
 * Written by Robert Simpson (robert@blackcastlesoft.com)
 * 
 * Released to the public domain, use at your own risk!
 ********************************************************/

namespace SQLite.Designer.Design
{
  using System;
  using System.Collections.Generic;
  using System.Collections;
  using System.Text;
  using System.ComponentModel;
  using System.ComponentModel.Design;
  using System.Windows.Forms;
  using System.Drawing.Design;
  using System.Data;
  using System.Data.Common;

  public enum TriggerOccurs
  {
    Before = 0,
    After = 1,
  }
  
  public enum ViewTriggerOccurs
  {
    InsteadOf = 2
  }

  public enum TriggerType
  {
    Delete = 0,
    Insert = 1,
    Update = 2,
  }

  internal class ViewTrigger : Trigger, ICloneable
  {
    internal ViewTrigger(ViewTrigger source)
      : base(source)
    {
      _triggerOccurs = (int)ViewTriggerOccurs.InsteadOf;
    }

    internal ViewTrigger(ViewTableBase parent, DataRow row)
      : base(parent, row)
    {
      _triggerOccurs = (int)ViewTriggerOccurs.InsteadOf;
    }

    [Browsable(true)]
    [DefaultValue(ViewTriggerOccurs.InsteadOf)]
    [Category("Event")]
    [Description("Determines when the trigger fires.  For tables, Before or After are supported.  For views, Instead Of is the only option.")]
    public new ViewTriggerOccurs Occurs
    {
      get
      {
        return ViewTriggerOccurs.InsteadOf;
      }
    }

    #region ICloneable Members

    object ICloneable.Clone()
    {
      return new ViewTrigger(this);
    }

    #endregion
  }

  [DefaultProperty("SQL")]
  internal class Trigger : IHaveConnection, ICloneable
  {
    protected int _triggerOccurs;
    private TriggerType _type = TriggerType.Update;
    //private bool _eachRow;
    private string _when;
    private ViewTableBase _table;
    private string _name;
    private string _columns;
    private string _action;
    private bool _calcname;
    private string _origsql;
    private bool _dirty = false;

    protected Trigger(Trigger source)
    {
      _triggerOccurs = source._triggerOccurs;
      _type = source._type;
      //_eachRow = source._eachRow;
      _when = source._when;
      _table = source._table;
      _name = source._name;
      _columns = source._columns;
      _action = source._action;
      _dirty = source._dirty;
    }

    internal void MakeDirty()
    {
      _dirty = true;
    }

    [Browsable(false)]
    internal bool IsDirty
    {
      get { return _dirty; }
    }

    internal void ClearDirty()
    {
      _dirty = false;
    }

    internal virtual void WriteSql(StringBuilder builder)
    {
      WriteSql(builder, false);
    }

    private void WriteSql(StringBuilder builder, bool temp)
    {
      string name = Name;

      if (temp == true)
        name = String.Format("{0}_{1}", name, Guid.NewGuid().ToString("N"));

      builder.AppendFormat("CREATE TRIGGER [{0}].[{1}]", _table.Catalog, name);
      switch (_triggerOccurs)
      {
        case 0:
          builder.Append(" BEFORE");
          break;
        case 1:
          builder.Append(" AFTER");
          break;
        case 2:
          builder.Append(" INSTEAD OF");
          break;
      }

      builder.AppendFormat(" {0}", _type.ToString().ToUpperInvariant());
      if (_type == TriggerType.Update && String.IsNullOrEmpty(Columns) == false)
        builder.AppendFormat(" OF {0}", Columns);

      builder.AppendFormat(" ON [{0}].[{1}]", _table.Catalog, _table.Name);

      if (EachRow)
        builder.AppendFormat(" FOR EACH ROW");
      if (String.IsNullOrEmpty(When) == false)
        builder.AppendFormat(" WHEN {0}", When);

      builder.AppendFormat("\r\nBEGIN\r\n{0}", SQL);
      SimpleTokenizer.StringParts[] arr = SimpleTokenizer.BreakString(SQL);
      if (arr[arr.Length - 1].sepchar != ';')
        builder.Append(";");

      builder.Append("\r\nEND;");
    }

    [DefaultValue(TriggerOccurs.Before)]
    [Category("Event")]
    [Description("Determines when the trigger fires.  For tables, Before or After are supported.  For views, Instead Of is the only option.")]
    public virtual TriggerOccurs Occurs
    {
      get { return (TriggerOccurs)_triggerOccurs; }
      set
      {
        if (_triggerOccurs != (int)value)
        {
          _triggerOccurs = (int)value;
          MakeDirty();
        }
      }
    }

    [DefaultValue(TriggerType.Update)]
    [Category("Event")]
    [Description("Determines what type of operation the trigger applies to.  Can be either Insert, Update or Delete.")]
    public TriggerType Type
    {
      get { return _type; }
      set
      {
        if (_type != value)
        {
          _type = value;
          MakeDirty();
        }
      }
    }

    [DefaultValue(true)]
    [Category("Event")]
    [Description("When set to true, the trigger will fire for each row in an update, insert or delete operation.")]
    public bool EachRow
    {
      get { return true; }
      //get { return _eachRow; }
      //set { _eachRow = value; }
    }

    [Category("Constraint")]
    [Description("Limits the exection of the trigger so it only occurs when the expression evaluates to True.")]
    public string When
    {
      get { return _when; }
      set
      {
        if (_when != value)
        {
          _when = value;
          MakeDirty();
        }
      }
    }

    [Browsable(false)]
    protected virtual string NamePrefix
    {
      get { return "TRG"; }
    }

    [Browsable(false)]
    protected virtual string NewName
    {
      get { return "NewTrigger"; }
    }

    [Browsable(false)]
    internal ViewTableBase ViewTableBase
    {
      get { return _table; }
    }

    [ParenthesizePropertyName(true)]
    [Category("Identity")]
    [Description("The name of the trigger")]
    public string Name
    {
      get
      {
        if (String.IsNullOrEmpty(_name))
        {
          if (_calcname == true) return GetHashCode().ToString();

          string name = String.Format("{0}_{1}", NamePrefix, NewName);
          int count = 0;
          string proposed = name;

          _calcname = true;
          for (int n = 0; n < ((IList)_table.Triggers).Count; n++)
          {
            Trigger idx = ((IList)_table.Triggers)[n] as Trigger;
            proposed = string.Format("{0}{1}", name, (count > 0) ? count.ToString() : "");
            if (idx.Name == proposed)
            {
              count++;
              n = -1;
            }
          }
          _calcname = false;
          return proposed;
        }
        return _name;
      }
      set
      {
        if (_name != value)
        {
          _name = value;
          MakeDirty();
        }
      }
    }

    [Editor(typeof(ColumnsMultiSelectEditor), typeof(UITypeEditor))]
    [Category("Event")]
    [DisplayName("Update Columns")]
    [Description("Limit the trigger to only occur when updating these columns")]
    public string Columns
    {
      get { return _columns; }
      set
      {
        if (_columns != value)
        {
          _columns = value;
          MakeDirty();
        }
      }
    }

    [Category("Action")]
    [Description("The SQL to execute for this trigger")]
    public string SQL
    {
      get { return _action; }
      set
      {
        //using (DbTransaction trans = GetConnection().BeginTransaction())
        //using (DbCommand cmd = GetConnection().CreateCommand())
        //{
        //  StringBuilder builder = new StringBuilder();
        //  WriteSql(builder, true);
        //  cmd.CommandText = builder.ToString();

        //  cmd.ExecuteNonQuery();
        //  trans.Rollback();
        //}
        if (_action != value)
        {
          _action = value;
          MakeDirty();
        }
      }
    }

    [Browsable(false)]
    public string OriginalSql
    {
      get { return _origsql; }
    }

    internal Trigger(ViewTableBase parent, DataRow row)
    {
      _table = parent;
      if (row != null)
      {
        _name = row["TRIGGER_NAME"].ToString();

        string sql = row["TRIGGER_DEFINITION"].ToString();
        _origsql = sql;
        SimpleTokenizer.StringParts[] arr = SimpleTokenizer.BreakString(sql);

        int x = 3;
        switch (arr[x].keyword)
        {
          case "BEFORE":
            _triggerOccurs = 0;
            break;
          case "AFTER":
            _triggerOccurs = 1;
            break;
          case "INSTEAD":
            _triggerOccurs = 2;
            x++;
            break;
          default:
            x--;
            break;
        }
        x++;

        switch (arr[x].keyword)
        {
          case "UPDATE":
            _type = TriggerType.Update;
            if (arr[x + 1].keyword == "OF")
            {
              x++;
              StringBuilder builder = new StringBuilder();
              string separator = "";
              while (arr[x + 1].keyword != "ON")
              {
                builder.AppendFormat("{0}[{1}]", separator, arr[x + 1].value);
                separator = ", ";
                x++;
              }
              _columns = builder.ToString();
            }
            break;
          case "INSERT":
            _type = TriggerType.Insert;
            break;
          case "DELETE":
            _type = TriggerType.Delete;
            break;
        }
        x++;

        while (arr[x].keyword != "BEGIN")
        {
          if (arr[x].keyword == "FOR" && arr[x + 1].keyword == "EACH" && arr[x + 1].keyword == "ROW")
          {
            //_eachRow = true;
            x += 3;
            continue;
          }

          if (arr[x].keyword == "WHEN")
          {
            x++;
            int depth = 0;
            StringBuilder builder = new StringBuilder();
            while (arr[x].keyword != "BEGIN")
            {
              if (builder.Length > 0) builder.Append(" ");
              while (depth < arr[x].depth)
              {
                depth++;
                builder.Append("(");
              }
              while (depth > arr[x].depth)
              {
                depth--;
                builder.Append(")");
              }

              if (String.IsNullOrEmpty(arr[x].quote) == false)
                builder.Append(arr[x].quote[0]);
              builder.Append(arr[x].value);
              if (String.IsNullOrEmpty(arr[x].quote) == false)
                builder.Append(arr[x].quote[1]);
            }
            while (depth > 0)
            {
              depth--;
              builder.Append(")");
            }
            _when = builder.ToString();
            break;
          }
          x++;
        }

        int startpos = arr[x].position + arr[x].value.Length;

        x = arr.Length - 1;
        while (arr[x].keyword != "END")
        {
          x--;
        }
        int endpos = arr[x].position;

        _action = sql.Substring(startpos, endpos - startpos);
        _action = _action.TrimStart('\r').TrimStart('\n').TrimEnd('\n').TrimEnd('\r').Trim();
      }
    }

    #region IHaveConnection Members

    public DbConnection GetConnection()
    {
      return ((IHaveConnection)_table).GetConnection();
    }

    #endregion

    #region ICloneable Members

    object ICloneable.Clone()
    {
      return new Trigger(this);
    }

    #endregion
  }

  internal class TriggerEditor : CollectionEditor
  {
    ViewTableBase _table;
    object[] _items;
    object[] _orig;
    CollectionEditor.CollectionForm _form;
    int _count;

    internal TriggerEditor(ViewTableBase parent)
      : base((parent is View) ? typeof(List<ViewTrigger>) :  typeof(List<Trigger>))
    {
      _table = parent;
    }

    protected override CollectionEditor.CollectionForm CreateCollectionForm()
    {
      _form = base.CreateCollectionForm();
      _form.Text = "Trigger Editor";
      foreach (Control c in _form.Controls[0].Controls)
      {
        PropertyGrid grid = c as PropertyGrid;
        if (grid != null)
        {
          grid.HelpVisible = true;
          break;
        }
      }
      _form.Width = (int)(_form.Width * 1.25);
      _form.Height = (int)(_form.Height * 1.25);
      return _form;
    }

    protected override object CreateInstance(Type itemType)
    {
      if (itemType == typeof(Trigger))
      {
        return new Trigger(_table, null);
      }
      else if (itemType == typeof(ViewTrigger))
      {
        return new ViewTrigger(_table, null);
      }
      throw new NotSupportedException();
    }

    protected override object[] GetItems(object editValue)
    {
      if (_items == null)
      {
        IList value = editValue as IList;
        _items = new object[value.Count];
        _orig = new object[value.Count];
        for (int n = 0; n < _items.Length; n++)
        {
          _items[n] = ((ICloneable)value[n]).Clone();
          _orig[n] = value[n];
        }
        _count = _items.Length;
      }
      return _items;
    }

    protected override object SetItems(object editValue, object[] value)
    {
      bool dirty = false;
      if (_form.DialogResult == DialogResult.Cancel)
        value = _orig;

      if (editValue != null)
      {
        int length = this.GetItems(editValue).Length;
        int num2 = value.Length;
        if (!(editValue is IList))
        {
          return editValue;
        }
        IList list = (IList)editValue;
        list.Clear();
        for (int i = 0; i < value.Length; i++)
        {
          Trigger trig = value[i] as Trigger;

          if (trig != null && String.IsNullOrEmpty(trig.SQL) == false)
          {
            if (trig.IsDirty) dirty = true;
            trig.Name = trig.Name;
            list.Add(trig);
          }
        }

        if ((dirty == true || list.Count != _count) && _form.DialogResult == DialogResult.OK)
          _table.MakeDirty();
      }

      return editValue;
    }
  }
}

/********************************************************
 * ADO.NET 2.0 Data Provider for SQLite Version 3.X
 * Written by Robert Simpson (robert@blackcastlesoft.com)

 * 
 * Released to the public domain, use at your own risk!

 ********************************************************/

namespace SQLite.Designer.Design
{
  using System;
  using System.Collections.Generic;
  using System.Text;
  using System.ComponentModel;
  using System.Data;
  using System.Data.Common;

  [TypeConverter(typeof(ExpandableObjectConverter))]
  [DefaultProperty("Enabled")]
  internal class Unique : IHaveConnection
  {
    private bool _isUnique;
    private ConflictEnum _conflict = ConflictEnum.Abort;
    private Column _column;

    }

    #endregion


    [DefaultValue(false)]
    [DisplayName("Enabled")]
    [RefreshProperties(RefreshProperties.All)]
    [Description("When enabled, all values entered into this column must be unique.")]
    public bool Enabled
    {
      get { return _isUnique; }
      set
      {
        if (value != _isUnique)
        {
          _isUnique = value;
          _column.Table._owner.MakeDirty();
        }
      }
    }

    [DefaultValue(ConflictEnum.Abort)]
    [DisplayName("On Conflict")]
    [RefreshProperties(RefreshProperties.All)]
    [Description("Specifies what action to take when the unique constraint on the column is violated.")]
    public ConflictEnum Conflict
    {
      get { return _conflict; }
      set
      {
        if (_conflict != value)
        {
          _conflict = value;
          
          if (_conflict != ConflictEnum.Abort && _isUnique == false)
            _isUnique = true;

          _column.Table._owner.MakeDirty();
        }
      }
    }

    public override string ToString()
    {

/********************************************************
 * ADO.NET 2.0 Data Provider for SQLite Version 3.X
 * Written by Robert Simpson (robert@blackcastlesoft.com)
 * 
 * Released to the public domain, use at your own risk!
 ********************************************************/

namespace SQLite.Designer.Design
{
  using System;
  using System.Data.Common;
  using System.ComponentModel.Design;
  using System.ComponentModel;
  using System.Drawing.Design;
  using System.Collections.Generic;
  using System.Data;
  using System.Text;
  using SQLite.Designer.Editors;

  internal class View : ViewTableBase, ICustomTypeDescriptor
  {
    private string _name;
    private string _oldname;
    private string _sql;
    private string _oldsql;
    private ViewDesignerDoc _owner;
    private string _catalog;
    private DbConnection _connection;
    List<ViewTrigger> _triggers = new List<ViewTrigger>();
    List<ViewTrigger> _oldtriggers = new List<ViewTrigger>();

    internal View(string viewName, DbConnection connection, ViewDesignerDoc parent)
    {
      _owner = parent;
      _name = viewName;
      _oldname = viewName;
      _catalog = connection.Database;
      _connection = connection;
      _owner.Name = _name;

      if (String.IsNullOrEmpty(viewName) == false)
      {
        using (DataTable tbl = connection.GetSchema("Views", new string[] { Catalog, null, Name }))
        {
          if (tbl.Rows.Count > 0)
          {
            _sql = tbl.Rows[0]["VIEW_DEFINITION"].ToString();

            StringBuilder builder = new StringBuilder();
            builder.Append(_sql);
            builder.AppendLine(";");

            _triggers.Clear();
            _oldtriggers.Clear();

            using (DataTable ttbl = _connection.GetSchema("Triggers", new string[] { Catalog, null, Name }))
            {
              foreach (DataRow row in ttbl.Rows)
              {
                ViewTrigger t = new ViewTrigger(this, row);
                _triggers.Add(t);
                _oldtriggers.Add(((ICloneable)t).Clone() as ViewTrigger);

                builder.AppendFormat("{0};\r\n", t.OriginalSql);
              }
            }
            _oldsql = builder.ToString();
          }
          else
          {
            _oldname = null;
          }
        }
      }
    }

    public override void MakeDirty()
    {
      _owner.MakeDirty();
    }

    [Browsable(false)]
    public override object Triggers
    {
      get { return _triggers; }
    }

    public void Committed()
    {
      _oldsql = _sql;
      _oldname = _name;

      _oldtriggers = _triggers;
      _triggers.Clear();
      foreach (ViewTrigger trig in _oldtriggers)
      {
        _triggers.Add(((ICloneable)trig).Clone() as ViewTrigger);
      }
    }

    public override string ToString()
    {
      return String.Format("[{0}].[{1}]", Catalog, Name);
    }

    [Category("Storage")]
    [RefreshProperties(RefreshProperties.All)]
    [ParenthesizePropertyName(true)]
    public override string Name
    {
      get { return _name; }
      set
      {
        if (_name != value)
        {
          _name = value;
          _owner.Name = value;
          _owner.MakeDirty();
        }
      }
    }
  
    [Category("Storage")]
    [Editor(typeof(CatalogTypeEditor), typeof(UITypeEditor))]
    [DefaultValue("main")]
    [RefreshProperties(RefreshProperties.All)]
    public override string Catalog
    {
      get { return _catalog; }










    }






    [Category("Storage")]
    public string Database
    {
      get { return _connection.DataSource; }
    }

    [Browsable(false)]

    public string GetSqlText()
    {
      if (String.Compare(_sql, _oldsql, StringComparison.OrdinalIgnoreCase) == 0 && String.Compare(_name, _oldname, StringComparison.OrdinalIgnoreCase) == 0) return null;

      StringBuilder builder = new StringBuilder();

      if (String.IsNullOrEmpty(_oldname) == false)
      {
        foreach (ViewTrigger trig in _oldtriggers)
        {
          builder.AppendFormat("DROP TRIGGER [{0}].[{1}];\r\n", Catalog, trig.Name);
        }
        builder.AppendFormat("DROP VIEW [{0}].[{1}];\r\n", Catalog, _oldname);
      }

      builder.AppendFormat("CREATE VIEW [{0}].[{1}] AS {2};\r\n", Catalog, Name, SqlText);

      string sep = "";
      foreach (ViewTrigger trig in _triggers)
      {
        builder.Append(sep);
        trig.WriteSql(builder);
        sep = "\r\n";
      }

      return builder.ToString();
    }

    #region ICustomTypeDescriptor Members

    AttributeCollection ICustomTypeDescriptor.GetAttributes()

    object ICustomTypeDescriptor.GetPropertyOwner(PropertyDescriptor pd)
    {
      return this;
    }

    #endregion



    public override DbConnection GetConnection()
    {
      return _connection;
    }
  }

}

/********************************************************
 * ADO.NET 2.0 Data Provider for SQLite Version 3.X




 * Written by Robert Simpson (robert@blackcastlesoft.com)
 * 
 * Released to the public domain, use at your own risk!



 ********************************************************/



namespace SQLite.Designer.Editors

{





  using System;









  using System.Windows.Forms;




  using System.Runtime.InteropServices;
  using System.Drawing;

  public class AutoCompleteColumn : DataGridViewColumn
  {
    public AutoCompleteColumn()
      : base(new AutoCompleteCell())
    {
    }
  }

  public class AutoCompleteCell : DataGridViewTextBoxCell
  {
    public override Type EditType
    {
      get
      {
        return typeof(AutoCompleteEditingControl);
      }
    }





  }

  public class AutoCompleteEditingControl : DataGridViewComboBoxEditingControl
  {
    private bool inPrepare = false;
    private bool isDeleting = false;

        base.Items.Add("nvarchar(50)");
        base.Items.Add("text");
        base.Items.Add("ntext");
        base.Items.Add("image");
        base.Items.Add("money");
        base.Items.Add("float");
        base.Items.Add("real");
        base.Items.Add("decimal");
        base.Items.Add("numeric(18,0)");
        base.Items.Add("char(10)");
        base.Items.Add("nchar(10)");
        base.Items.Add("datetime");
        base.Items.Add("guid");
      }
      base.DropDownStyle = ComboBoxStyle.DropDown;

    /// Required method for Designer support - do not modify
    /// the contents of this method with the code editor.
    /// </summary>
    private void InitializeComponent()
    {
      this.components = new System.ComponentModel.Container();
      System.Windows.Forms.SplitContainer _splitter;

      System.ComponentModel.ComponentResourceManager resources = new System.ComponentModel.ComponentResourceManager(typeof(TableDesignerDoc));
      this._dataGrid = new System.Windows.Forms.DataGridView();
      this.name = new System.Windows.Forms.DataGridViewTextBoxColumn();
      this.type = new SQLite.Designer.Editors.AutoCompleteColumn();
      this.isnull = new System.Windows.Forms.DataGridViewCheckBoxColumn();

      this._propertyGrid = new System.Windows.Forms.PropertyGrid();
      this._sqlText = new System.Windows.Forms.RichTextBox();
      this.autoCompleteColumn1 = new SQLite.Designer.Editors.AutoCompleteColumn();
      this._imageList = new System.Windows.Forms.ImageList(this.components);

      this._pg = new System.Windows.Forms.PropertyGrid();
      _splitter = new System.Windows.Forms.SplitContainer();

      _splitter.Panel1.SuspendLayout();
      _splitter.Panel2.SuspendLayout();
      _splitter.SuspendLayout();



      ((System.ComponentModel.ISupportInitialize)(this._dataGrid)).BeginInit();
      this.SuspendLayout();
      // 
      // _splitter
      // 
      _splitter.BackColor = System.Drawing.SystemColors.Control;
      _splitter.Dock = System.Windows.Forms.DockStyle.Fill;
      _splitter.Location = new System.Drawing.Point(0, 0);
      _splitter.Name = "_splitter";
      _splitter.Orientation = System.Windows.Forms.Orientation.Horizontal;
      // 
      // _splitter.Panel1
      // 
      _splitter.Panel1.Controls.Add(this._dataGrid);
      _splitter.Panel1.Controls.Add(this._pg);
      _splitter.Panel1.Controls.Add(this._sqlText);
      // 
      // _splitter.Panel2
      // 
      _splitter.Panel2.Controls.Add(this._propertyGrid);
      _splitter.Size = new System.Drawing.Size(436, 631);
      _splitter.SplitterDistance = 383;
      _splitter.TabIndex = 0;
      // 


















      // _dataGrid
      // 
      this._dataGrid.AllowDrop = true;
      this._dataGrid.AllowUserToResizeRows = false;
      this._dataGrid.BackgroundColor = System.Drawing.SystemColors.Window;
      this._dataGrid.ColumnHeadersHeightSizeMode = System.Windows.Forms.DataGridViewColumnHeadersHeightSizeMode.AutoSize;
      this._dataGrid.Columns.AddRange(new System.Windows.Forms.DataGridViewColumn[] {
            this.name,
            this.type,
            this.isnull});
      this._dataGrid.Dock = System.Windows.Forms.DockStyle.Fill;
      this._dataGrid.Location = new System.Drawing.Point(0, 0);
      this._dataGrid.Name = "_dataGrid";
      this._dataGrid.RowHeadersWidth = 42;
      this._dataGrid.RowHeadersWidthSizeMode = System.Windows.Forms.DataGridViewRowHeadersWidthSizeMode.DisableResizing;
      this._dataGrid.RowTemplate.Height = 23;
      this._dataGrid.Size = new System.Drawing.Size(436, 383);
      this._dataGrid.TabIndex = 2;
      this._dataGrid.CellValueChanged += new System.Windows.Forms.DataGridViewCellEventHandler(this._dataGrid_CellValueChanged);
      this._dataGrid.MouseDown += new System.Windows.Forms.MouseEventHandler(this._dataGrid_MouseDown);
      this._dataGrid.UserDeletingRow += new System.Windows.Forms.DataGridViewRowCancelEventHandler(this._dataGrid_UserDeletingRow);
      this._dataGrid.MouseMove += new System.Windows.Forms.MouseEventHandler(this._dataGrid_MouseMove);
      this._dataGrid.CellValidated += new System.Windows.Forms.DataGridViewCellEventHandler(this._dataGrid_CellValidated);
      this._dataGrid.UserDeletedRow += new System.Windows.Forms.DataGridViewRowEventHandler(this._dataGrid_UserDeletedRow);
      this._dataGrid.DragOver += new System.Windows.Forms.DragEventHandler(this._dataGrid_DragOver);
      this._dataGrid.CellEndEdit += new System.Windows.Forms.DataGridViewCellEventHandler(this._dataGrid_CellValidated);
      this._dataGrid.CellPainting += new System.Windows.Forms.DataGridViewCellPaintingEventHandler(this._dataGrid_CellPainting);
      this._dataGrid.CellClick += new System.Windows.Forms.DataGridViewCellEventHandler(this._dataGrid_CellClick);
      this._dataGrid.CellEnter += new System.Windows.Forms.DataGridViewCellEventHandler(this._dataGrid_CellEnter);

      this._dataGrid.RowHeaderMouseClick += new System.Windows.Forms.DataGridViewCellMouseEventHandler(this._dataGrid_RowHeaderMouseClick);
      this._dataGrid.SelectionChanged += new System.EventHandler(this._dataGrid_SelectionChanged);
      this._dataGrid.DragDrop += new System.Windows.Forms.DragEventHandler(this._dataGrid_DragDrop);
      // 
      // name
      // 
      this.name.Frozen = true;
      this.name.HeaderText = "Column Name";
      this.name.Name = "name";
      this.name.SortMode = System.Windows.Forms.DataGridViewColumnSortMode.NotSortable;
      // 
      // type
      // 
      this.type.HeaderText = "Data Type";
      this.type.Name = "type";
      // 
      // isnull
      // 
      this.isnull.HeaderText = "Allow Nulls";
      this.isnull.Name = "isnull";
      // 










      // _propertyGrid
      // 
      this._propertyGrid.Dock = System.Windows.Forms.DockStyle.Fill;
      this._propertyGrid.Location = new System.Drawing.Point(0, 0);
      this._propertyGrid.Name = "_propertyGrid";
      this._propertyGrid.Size = new System.Drawing.Size(436, 244);
      this._propertyGrid.TabIndex = 0;
      // 
      // _sqlText
      // 
      this._sqlText.Font = new System.Drawing.Font("Courier New", 8.25F, System.Drawing.FontStyle.Regular, System.Drawing.GraphicsUnit.Point, ((byte)(0)));
      this._sqlText.Location = new System.Drawing.Point(3, 3);
      this._sqlText.Name = "_sqlText";
      this._sqlText.ReadOnly = true;
      this._sqlText.Size = new System.Drawing.Size(165, 162);
      this._sqlText.TabIndex = 0;
      this._sqlText.Text = "";
      this._sqlText.Visible = false;
      // 
      // autoCompleteColumn1
      // 
      this.autoCompleteColumn1.HeaderText = "Data Type";
      this.autoCompleteColumn1.Name = "autoCompleteColumn1";
      this.autoCompleteColumn1.Resizable = System.Windows.Forms.DataGridViewTriState.True;
      this.autoCompleteColumn1.SortMode = System.Windows.Forms.DataGridViewColumnSortMode.Automatic;
      // 
      // _imageList
      // 
      this._imageList.ImageStream = ((System.Windows.Forms.ImageListStreamer)(resources.GetObject("_imageList.ImageStream")));
      this._imageList.TransparentColor = System.Drawing.Color.Magenta;
      this._imageList.Images.SetKeyName(0, "PrimaryKey.bmp");
      // 




      // _pg
      // 
      this._pg.Location = new System.Drawing.Point(3, 171);
      this._pg.Name = "_pg";
      this._pg.PropertySort = System.Windows.Forms.PropertySort.NoSort;
      this._pg.Size = new System.Drawing.Size(130, 130);
      this._pg.TabIndex = 1;
      this._pg.ToolbarVisible = false;
      this._pg.Visible = false;
      // 
      // TableDesignerDoc
      // 
      this.AutoScaleDimensions = new System.Drawing.SizeF(6F, 13F);
      this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font;
      this.BackColor = System.Drawing.SystemColors.Window;

      this.Controls.Add(_splitter);

      this.Name = "TableDesignerDoc";
      this.Size = new System.Drawing.Size(436, 631);

      _splitter.Panel1.ResumeLayout(false);
      _splitter.Panel2.ResumeLayout(false);
      _splitter.ResumeLayout(false);



      ((System.ComponentModel.ISupportInitialize)(this._dataGrid)).EndInit();
      this.ResumeLayout(false);

    }

    #endregion

    private System.Windows.Forms.PropertyGrid _propertyGrid;
    private AutoCompleteColumn autoCompleteColumn1;
    private System.Windows.Forms.ImageList _imageList;
    private System.Windows.Forms.DataGridView _dataGrid;
    private System.Windows.Forms.DataGridViewTextBoxColumn name;
    private AutoCompleteColumn type;
    private System.Windows.Forms.DataGridViewCheckBoxColumn isnull;
    private System.Windows.Forms.RichTextBox _sqlText;

    private System.Windows.Forms.PropertyGrid _pg;

  }
}

/********************************************************
 * ADO.NET 2.0 Data Provider for SQLite Version 3.X
 * Written by Robert Simpson (robert@blackcastlesoft.com)
 * 
 * Released to the public domain, use at your own risk!
 ********************************************************/

namespace SQLite.Designer.Editors
{
  using System;
  using System.Collections.Generic;
  using System.ComponentModel;
  using System.Data;
  using System.Data.Common;

    private static Dictionary<int, string> _editingTables = new Dictionary<int, string>();
    
    internal DataConnection _connection;
    internal Microsoft.VisualStudio.Data.ServiceProvider _serviceProvider;
    internal Table _table;
    internal bool _dirty;
    internal bool _init = false;
    internal DataViewHierarchyAccessor _accessor;
    internal int _itemId;
    static private bool _warned = false;

    public TableDesignerDoc(int itemId, DataViewHierarchyAccessor accessor, string tableName)
    {
      _accessor = accessor;
      _connection = accessor.Connection;
      _itemId = itemId;
      _init = true;

      InitializeComponent();

      StringBuilder tables = new StringBuilder();

      using (DataReader reader = _connection.Command.Execute("SELECT * FROM sqlite_master", 1, null, 30))
      {
        while (reader.Read())
        {
          tables.Append(reader.GetItem(2).ToString());
          tables.Append(",");
        }
      }

        shell.UpdateDocDataIsDirtyFeedback(docCookie, (_dirty == true) ? 1 : 0);
      }

      // Unlock the document.
      // Note that we have to unlock the document even if the previous call failed.
      runningDocTable.UnlockDocument((uint)_VSRDTFLAGS.RDT_ReadLock, docCookie);


      // Check ff the call to NotifyDocChanged failed.
      //ErrorHandler.ThrowOnFailure(hr);
    }

    #region IVsPersistDocData Members

    int IVsPersistDocData.Close()

    }

    public int RenameDocData(uint grfAttribs, IVsHierarchy pHierNew, uint itemidNew, string pszMkDocumentNew)
    {
      return VSConstants.E_NOTIMPL;
    }





    private string GetChangeScript()

    {










      _dataGrid.EndEdit();
      _init = true;
      for (int n = 0; n < _table.Columns.Count; n++)
      {
        Column c = _table.Columns[n];
        if (String.IsNullOrEmpty(c.ColumnName) == true)
        {
          try
          {
            _dataGrid.Rows.Remove(c.Parent);
          }
          catch
          {
            c.Parent.Tag = null;
          }
          _table.Columns.Remove(c);
          n--;
          continue;
        }
      }

      for (int n = 0; n < _dataGrid.Rows.Count; n++)

            if (n == _dataGrid.Rows.Count - 1) break;
          }
          n--;
        }
      }
      _init = false;

      return _table.GetSql();
    }

    public int SaveDocData(VSSAVEFLAGS dwSave, out string pbstrMkDocumentNew, out int pfSaveCanceled)
    {
      pbstrMkDocumentNew = _table.Name;
      pfSaveCanceled = 0;

      if (String.IsNullOrEmpty(_table.OriginalSql) == true)
      {
        using (TableNameDialog dlg = new TableNameDialog("Table", _table.Name))
        {
          if (dlg.ShowDialog(this) == DialogResult.Cancel)
          {
            pfSaveCanceled = 1;
            return VSConstants.S_OK;
          }
          _table.Name = dlg.TableName;
        }
      }

      string sql = GetChangeScript();

      using (DbTransaction trans = _table.GetConnection().BeginTransaction())
      {
        try
        {
          using (DbCommand cmd = _table.GetConnection().CreateCommand())
          {
            cmd.CommandText = sql;
            cmd.ExecuteNonQuery();
          }
          trans.Commit();
        }
        catch (Exception)
        {
          trans.Rollback();
          throw;
        }
      }

      _dirty = false;
      _table.Committed();
      NotifyChanges();
      _sqlText.Text = _table.OriginalSql;

      SQLiteCommandHandler.Refresh(_accessor, _itemId);

      _dataGrid_SelectionChanged(this, EventArgs.Empty);

      RefreshToolbars();

      return VSConstants.S_OK;
    }

    public int SetUntitledDocPath(string pszDocDataPath)
    {
      return ((IPersistFileFormat)this).InitNew(0);
    }

    #endregion

    #region IVsWindowPane Members

    public int ClosePane()
    {












      this.Dispose(true);
      return VSConstants.S_OK;
    }

    public int CreatePaneWindow(IntPtr hwndParent, int x, int y, int cx, int cy, out IntPtr hwnd)
    {
      Win32Methods.SetParent(Handle, hwndParent);

      return newVal;
    }

    #region IOleCommandTarget Members

    public int Exec(ref Guid pguidCmdGroup, uint nCmdID, uint nCmdexecopt, IntPtr pvaIn, IntPtr pvaOut)
    {
      System.Diagnostics.Debug.WriteLine(String.Format("{0} {1}", pguidCmdGroup, nCmdID));
      if (pguidCmdGroup == VSConstants.GUID_VSStandardCommandSet97)
      {
        switch ((VSConstants.VSStd97CmdID)nCmdID)
        {
          case VSConstants.VSStd97CmdID.GenerateChangeScript:
            {
              using (ChangeScriptDialog dlg = new ChangeScriptDialog(_table.Name, GetChangeScript()))
              {
                dlg.ShowDialog(this);
              }
            }
            return VSConstants.S_OK;
          case VSConstants.VSStd97CmdID.PrimaryKey:
            bool newVal = IsPkSelected();

            if (newVal == false)
            {
              _table.PrimaryKey.Columns.Clear();
              foreach (Column c in _propertyGrid.SelectedObjects)

                }
              }
            }

            _dataGrid_SelectionChanged(this, EventArgs.Empty);
            _dataGrid.Invalidate();
            MakeDirty();
            return VSConstants.S_OK;

          case VSConstants.VSStd97CmdID.Cut:
            _clipRows = SelectedRows;
            foreach (DataGridViewRow row in _clipRows)
            {
              _dataGrid.Rows.Remove(row);
              _table.Columns.Remove(row.Tag as Column);
              MakeDirty();
            }
            Clipboard.SetData("SQLiteTableDesigner", Caption);
            RefreshToolbars();
            return VSConstants.S_OK;

          case VSConstants.VSStd97CmdID.Copy:
            _clipRows = SelectedRows;
            Clipboard.SetData("SQLiteTableDesigner", Caption);
            RefreshToolbars();
            return VSConstants.S_OK;

          case VSConstants.VSStd97CmdID.Paste:
            DataGridViewRow[] arr = GetClipboardRows();
            int rowIndex = _dataGrid.CurrentRow.Index;
            _dataGrid.EndEdit();

            for (int n = arr.Length - 1; n > -1; n--)
            {
              DataGridViewRow row = arr[n];
              Column c = row.Tag as Column;
              bool hasCol = false;
              foreach (Column oc in _table.Columns)
              {
                if (String.Compare(c.ColumnName, oc.ColumnName, StringComparison.OrdinalIgnoreCase) == 0)
                {
                  hasCol = true;
                  break;
                }
              }
              _dataGrid.Rows.Insert(rowIndex, 1);
              DataGridViewRow newrow = _dataGrid.Rows[rowIndex];

              if (hasCol == true)
              {
                Column oc = c;
                c = new Column(_table, newrow);
                int num = 1;
                while (String.IsNullOrEmpty(c.ColumnName) == true)
                {
                  bool found = false;
                  string proposed = String.Format("{0}{1}", oc.ColumnName, num);
                  foreach (Column cc in _table.Columns)
                  {
                    if (String.Compare(cc.ColumnName, proposed, StringComparison.OrdinalIgnoreCase) == 0)
                    {
                      found = true;
                      break;
                    }
                  }
                  if (found == true)
                  {
                    num++;
                  }
                  else
                    c.ColumnName = proposed;
                }
                c.AllowNulls = oc.AllowNulls;
                c.Collate = oc.Collate;
                c.DataType = oc.DataType;
                c.DefaultValue = oc.DefaultValue;
                c.Unique.Enabled = oc.Unique.Enabled;
                c.Unique.Conflict = oc.Unique.Conflict;
              }

              c.Parent = newrow;
              newrow.Tag = c;
              newrow.SetValues(c.ColumnName, c.DataType, c.AllowNulls);
              _table.Columns.Insert(rowIndex, c);
            }
            
            MakeDirty();
            _dataGrid.Invalidate();

            return VSConstants.S_OK;
        }
      }
      else if (pguidCmdGroup == SQLiteCommandHandler.guidDavinci)
      {
        switch ((VSConstants.VSStd97CmdID)nCmdID)
        {
          case VSConstants.VSStd97CmdID.ManageIndexes:
            EditorHolder holder = new EditorHolder(_table);
            _pg.SelectedObject = holder;
            _pg.SelectedGridItem = _pg.SelectedGridItem.Parent.GridItems[0];
            IndexEditor ed = new IndexEditor(_table);
            ed.EditValue((ITypeDescriptorContext)_pg.SelectedGridItem, (System.IServiceProvider)_pg.SelectedGridItem, _pg.SelectedGridItem.Value);
            return VSConstants.S_OK;
          case VSConstants.VSStd97CmdID.ManageRelationships:
            holder = new EditorHolder(_table);
            _pg.SelectedObject = holder;
            _pg.SelectedGridItem = _pg.SelectedGridItem.Parent.GridItems[1];
            ForeignKeyEditor fed = new ForeignKeyEditor(_table);
            fed.EditValue((ITypeDescriptorContext)_pg.SelectedGridItem, (System.IServiceProvider)_pg.SelectedGridItem, _pg.SelectedGridItem.Value);
            return VSConstants.S_OK;
          
          case VSConstants.VSStd97CmdID.ManageConstraints:
            holder = new EditorHolder(_table);
            _pg.SelectedObject = holder;
            _pg.SelectedGridItem = _pg.SelectedGridItem.Parent.GridItems[2];
            CheckEditor ced = new CheckEditor(_table);
            ced.EditValue((ITypeDescriptorContext)_pg.SelectedGridItem, (System.IServiceProvider)_pg.SelectedGridItem, _pg.SelectedGridItem.Value);
            return VSConstants.S_OK;

          case VSConstants.VSStd97CmdID.AlignRight: // Insert Column
            _dataGrid.EndEdit();
            _dataGrid.Rows.Insert(_dataGrid.SelectedRows[0].Index, 1);
            return VSConstants.S_OK;
          case VSConstants.VSStd97CmdID.AlignToGrid: // Delete Column
            _dataGrid.EndEdit();
            int deleted = 0;
            while (_dataGrid.SelectedRows.Count > 0)
            {
              try
              {
                DataGridViewRow row = _dataGrid.SelectedRows[0];
                Column c = row.Tag as Column;
                row.Selected = false;
                if (c != null)
                {
                  _table.Columns.Remove(c);
                  deleted++;
                }
                _dataGrid.Rows.Remove(row);
              }
              catch
              {
              }
            }
            if (deleted > 0) MakeDirty();
            return VSConstants.S_OK;
        }
      }
      else if (pguidCmdGroup == SQLiteCommandHandler.guidSQLiteCmdSet)
      {
        switch ((cmdid)nCmdID)
        {
          case cmdid.Triggers:
            EditorHolder holder = new EditorHolder(_table);
            _pg.SelectedObject = holder;
            _pg.SelectedGridItem = _pg.SelectedGridItem.Parent.GridItems[3];
            TriggerEditor ted = new TriggerEditor(_table);
            ted.EditValue((ITypeDescriptorContext)_pg.SelectedGridItem, (System.IServiceProvider)_pg.SelectedGridItem, _pg.SelectedGridItem.Value);
            return VSConstants.S_OK;
        }
      }

      return (int)(Microsoft.VisualStudio.OLE.Interop.Constants.OLECMDERR_E_NOTSUPPORTED);
    }

    private DataGridViewRow[] _clipRows;

    private DataGridViewRow[] GetClipboardRows()
    {
      if (Clipboard.ContainsData("SQLiteTableDesigner") && Clipboard.GetData("SQLiteTableDesigner").ToString() == Caption)
      {
        DataGridViewRow[] arr = _clipRows;
        if (arr != null)
        {
          for (int n = 0; n < arr.Length; n++)
          {
            Column c = arr[n].Tag as Column;
            if (c != null && c.Table == _table) return arr;
          }
        }
      }
      return null;
    }

    public int QueryStatus(ref Guid pguidCmdGroup, uint cCmds, OLECMD[] prgCmds, IntPtr pCmdText)
    {
      if (pguidCmdGroup == VSConstants.GUID_VSStandardCommandSet97)
      {
        switch ((VSConstants.VSStd97CmdID)prgCmds[0].cmdID)
        {
          case VSConstants.VSStd97CmdID.PrimaryKey:
            prgCmds[0].cmdf = (uint)(OLECMDF.OLECMDF_SUPPORTED | OLECMDF.OLECMDF_ENABLED);
            if (IsPkSelected() == true)
              prgCmds[0].cmdf |= (uint)(OLECMDF.OLECMDF_LATCHED);

            break;
          case VSConstants.VSStd97CmdID.GenerateChangeScript:
            if (_dirty == true)
            {
              prgCmds[0].cmdf = (uint)(OLECMDF.OLECMDF_SUPPORTED | OLECMDF.OLECMDF_ENABLED);
              break;
            }
            return (int)(Microsoft.VisualStudio.OLE.Interop.Constants.OLECMDERR_E_NOTSUPPORTED);
          case VSConstants.VSStd97CmdID.Cut:
            if (SelectedRows.Length > 0)
            {
              prgCmds[0].cmdf = (uint)(OLECMDF.OLECMDF_SUPPORTED | OLECMDF.OLECMDF_ENABLED);
              break;
            }
            return (int)(Microsoft.VisualStudio.OLE.Interop.Constants.OLECMDERR_E_NOTSUPPORTED);
          case VSConstants.VSStd97CmdID.Copy:
            if (SelectedRows.Length > 0)
            {
              prgCmds[0].cmdf = (uint)(OLECMDF.OLECMDF_SUPPORTED | OLECMDF.OLECMDF_ENABLED);
              break;
            }
            return (int)(Microsoft.VisualStudio.OLE.Interop.Constants.OLECMDERR_E_NOTSUPPORTED);
          case VSConstants.VSStd97CmdID.Paste:
            DataGridViewRow[] rows = GetClipboardRows();
            if (rows != null)
            {
              prgCmds[0].cmdf = (uint)(OLECMDF.OLECMDF_SUPPORTED | OLECMDF.OLECMDF_ENABLED);
              break;
            }
            return (int)(Microsoft.VisualStudio.OLE.Interop.Constants.OLECMDERR_E_NOTSUPPORTED);
          default:
            return (int)(Microsoft.VisualStudio.OLE.Interop.Constants.OLECMDERR_E_NOTSUPPORTED);
        }
        return VSConstants.S_OK;
      }

      if (pguidCmdGroup == SQLiteCommandHandler.guidSQLiteCmdSet)
      {
        switch (prgCmds[0].cmdID)
        {
          case (uint)cmdid.Triggers:
            prgCmds[0].cmdf = (uint)(OLECMDF.OLECMDF_SUPPORTED | OLECMDF.OLECMDF_ENABLED);
            return VSConstants.S_OK;
        }
      }

      if (pguidCmdGroup == SQLiteCommandHandler.guidDavinci)
      {
        switch (prgCmds[0].cmdID)
        {
          case (uint)VSConstants.VSStd97CmdID.ManageRelationships:
          case (uint)VSConstants.VSStd97CmdID.ManageIndexes:
          case (uint)VSConstants.VSStd97CmdID.ManageConstraints:
          //case 10: // Table View -> Custom
          //case 14: // Table View -> Modify Custom
          //case 33: // Database Diagram -> Add Table
          //case 1: // Database Diagram -> Add Related Tables
          //case 12: // Database Diagram -> Delete From Database
          //case 51: // Database Diagram -> Remove From Diagram
          //case 13: // Database Diagram -> Autosize Selected Tables

    }

    int IVsWindowFrameNotify.OnMove()
    {
      return VSConstants.S_OK;
    }

























    int IVsWindowFrameNotify.OnShow(int fShow)
    {
      switch ((__FRAMESHOW)fShow)
      {
        case __FRAMESHOW.FRAMESHOW_WinShown:
        case __FRAMESHOW.FRAMESHOW_WinRestored:
          SetPropertyWindow();
          if (_warned == false)
          {
            _warned = true;


            MessageBox.Show(this, "The table designer is still in development.  Please report bugs to robert@blackcastlesoft.com", "Feature Under Review", MessageBoxButtons.OK);
          }
          break;
      }
      return VSConstants.S_OK;
    }

    int IVsWindowFrameNotify.OnSize()
    {
      return VSConstants.S_OK;
    }

    #endregion

    private void _dataGrid_CellEnter(object sender, DataGridViewCellEventArgs e)
    {
      try
      {
        if (e.ColumnIndex > -1)
        {
          _dataGrid.BeginEdit(true);
          _dataGrid_SelectionChanged(sender, e);
        }
      }
      catch
      {
      }
    }

    private void _dataGrid_RowHeaderMouseClick(object sender, DataGridViewCellMouseEventArgs e)
    {
      _dataGrid.EndEdit();
      if (e.Button == MouseButtons.Right)

      if (ispk == true)
      {
        e.Paint(e.ClipBounds, DataGridViewPaintParts.All);
        _imageList.Draw(e.Graphics, e.CellBounds.Left, e.CellBounds.Top + ((e.CellBounds.Bottom - e.CellBounds.Top) - _imageList.ImageSize.Height) / 2, 0);
        e.Handled = true;
      }
    }

    private DataGridViewRow[] SelectedRows
    {
      get
      {
        List<DataGridViewRow> items = new List<DataGridViewRow>();

        for (int n = 0; n < _dataGrid.Rows.Count; n++)
        {
          if (_dataGrid.Rows[n].Selected || (_dataGrid.CurrentCell.RowIndex == n && _dataGrid.CurrentCell.Selected == true))
          {
            if (_dataGrid.Rows[n].Tag is Column)
              items.Add(_dataGrid.Rows[n]);
          }
        }

        DataGridViewRow[] objs = new DataGridViewRow[items.Count];
        items.CopyTo(objs);

        return objs;
      }
    }

    private void _dataGrid_SelectionChanged(object sender, EventArgs e)
    {
      if (_init == true) return;
      DataGridViewRow[] arr = SelectedRows;

      object[] objs = new object[arr.Length];

      for (int n = 0; n < objs.Length; n++)
        objs[n] = arr[n].Tag;

      _propertyGrid.SelectedObjects = objs;

      RefreshToolbars();
    }

    private void _dataGrid_CellValueChanged(object sender, DataGridViewCellEventArgs e)
    {
      if (_init == true) return;
      if (e.RowIndex > -1)
      {

        _propertyGrid.SelectedObjects = _propertyGrid.SelectedObjects;
      }
    }

    private void _dataGrid_UserDeletedRow(object sender, DataGridViewRowEventArgs e)
    {
      if (_init == true) return;
      
      if (e.Row.Tag is Column)
        MakeDirty();

      _dataGrid_SelectionChanged(sender, e);
    }

    private void _dataGrid_UserDeletingRow(object sender, DataGridViewRowCancelEventArgs e)
    {
      if (_init == true) return;
      if (e.Row.Tag is Column)
      {
        _table.Columns.Remove(e.Row.Tag as Column);
      }
    }

    private void _dataGrid_RowsAdded(object sender, DataGridViewRowsAddedEventArgs e)
    {


    }

    private void _dataGrid_RowsRemoved(object sender, DataGridViewRowsRemovedEventArgs e)
    {

    }

    private Rectangle _dragBoxFromMouseDown;
    private int _rowIndexFromMouseDown;
    private int _rowIndexOfItemUnderMouseToDrop;

    private void _dataGrid_DragDrop(object sender, DragEventArgs e)
    {
      // The mouse locations are relative to the screen, so they must be 
      // converted to client coordinates.
      Point clientPoint = _dataGrid.PointToClient(new Point(e.X, e.Y));

      if (_rowIndexOfItemUnderMouseToDrop != -1)
        _dataGrid.Rows[_rowIndexOfItemUnderMouseToDrop].DividerHeight = 0;

      _rowIndexOfItemUnderMouseToDrop = _dataGrid.HitTest(clientPoint.X, clientPoint.Y).RowIndex;

      if (_rowIndexOfItemUnderMouseToDrop != -1)
        _dataGrid.Rows[_rowIndexOfItemUnderMouseToDrop].DividerHeight = 0;

      // If the drag operation was a move then remove and insert the row.
      if (e.Effect == DragDropEffects.Move)
      {
        DataGridViewRow[] rowsToMove = e.Data.GetData(typeof(DataGridViewRow[])) as DataGridViewRow[];
        for (int n = 0; n < rowsToMove.Length; n++)
        {
          _dataGrid.Rows.Remove(rowsToMove[n]);
          _table.Columns.Remove(rowsToMove[n].Tag as Column);
          _dataGrid.Rows.Insert(_rowIndexOfItemUnderMouseToDrop, rowsToMove[n]);
          _table.Columns.Insert(_rowIndexOfItemUnderMouseToDrop, rowsToMove[n].Tag as Column);
        }
        MakeDirty();
        RefreshToolbars();
      }
    }

    private void _dataGrid_DragOver(object sender, DragEventArgs e)
    {
      // The mouse locations are relative to the screen, so they must be 
      // converted to client coordinates.
      Point clientPoint = _dataGrid.PointToClient(new Point(e.X, e.Y));

      // Get the row index of the item the mouse is below. 
      if (_rowIndexOfItemUnderMouseToDrop != -1)
        _dataGrid.Rows[_rowIndexOfItemUnderMouseToDrop].DividerHeight = 0;

      _rowIndexOfItemUnderMouseToDrop = _dataGrid.HitTest(clientPoint.X, clientPoint.Y).RowIndex;

      if (_dataGrid.Rows[_rowIndexOfItemUnderMouseToDrop].IsNewRow == false && _rowIndexOfItemUnderMouseToDrop != _rowIndexFromMouseDown)
      {
        e.Effect = DragDropEffects.Move;

        if (_rowIndexOfItemUnderMouseToDrop != -1)
          _dataGrid.Rows[_rowIndexOfItemUnderMouseToDrop].DividerHeight = 3;
      }
      else
        e.Effect = DragDropEffects.None;
    }

    private void _dataGrid_MouseDown(object sender, MouseEventArgs e)
    {
      // Get the index of the item the mouse is below.
      _rowIndexFromMouseDown = _dataGrid.HitTest(e.X, e.Y).RowIndex;

      if (_rowIndexFromMouseDown != -1)
      {
        // Remember the point where the mouse down occurred. 
        // The DragSize indicates the size that the mouse can move 
        // before a drag event should be started. 
        Size dragSize = SystemInformation.DragSize;

        // Create a rectangle using the DragSize, with the mouse position being
        // at the center of the rectangle.
        _dragBoxFromMouseDown = new Rectangle(new Point(e.X - (dragSize.Width / 2), e.Y - (dragSize.Height / 2)), dragSize);
      }
      else
        // Reset the rectangle if the mouse is not over an item in the ListBox.
        _dragBoxFromMouseDown = Rectangle.Empty;
    }

    private void _dataGrid_MouseMove(object sender, MouseEventArgs e)
    {
      if ((e.Button & MouseButtons.Left) == MouseButtons.Left)
      {
        // If the mouse moves outside the rectangle, start the drag.
        if (_dragBoxFromMouseDown != Rectangle.Empty && !_dragBoxFromMouseDown.Contains(e.X, e.Y))
        {
          _rowIndexOfItemUnderMouseToDrop = -1;
          _dataGrid.EndEdit();
          // Proceed with the drag and drop, passing in the list item. 
          DragDropEffects dropEffect = _dataGrid.DoDragDrop(SelectedRows, DragDropEffects.Move);
        }
      }
    }

    private void _dataGrid_CellValidated(object sender, DataGridViewCellEventArgs e)
    {
      DataGridViewRow row = _dataGrid.Rows[e.RowIndex];
      Column col = row.Tag as Column;

      if (col == null && row.IsNewRow == false)
      {
        col = new Column(_table, row);
        row.Tag = col;
        _table.Columns.Insert(row.Index, col);
        _dataGrid_SelectionChanged(this, new EventArgs());
      }
      if (col != null)
        col.CellValueChanged(e.RowIndex, e.ColumnIndex);

      RefreshToolbars();
    }
  }

  internal class EditorHolder
  {
    private List<Index> _indexes;
    private List<ForeignKey> _fkeys;
    private List<string> _check;
    private List<Trigger> _triggers;

    internal EditorHolder(Table tbl)
    {
      _indexes = tbl.Indexes;
      _fkeys = tbl.ForeignKeys;
      _check = tbl.Check;
      _triggers = tbl.Triggers as List<Trigger>;
    }

    public List<Index> Indexes
    {
      get { return _indexes; }
    }

    public List<ForeignKey> ForeignKeys
    {
      get { return _fkeys; }
    }

    public List<string> Check
    {
      get { return _check; }
    }

    public List<Trigger> Triggers
    {
      get { return _triggers; }
    }
  }

  public class DesignerDocBase : UserControl
  {
    public virtual string CanonicalName
    {
      get

          pvar = 0;
          break;
        case __VSHPROPID.VSHPROPID_IconHandle:
          pvar = null;
          return VSConstants.S_OK;
      }








      if (pvar == null)
        return _owner.GetProperty(itemid, propid, out pvar);
      else
        return VSConstants.S_OK;
    }

    int IVsUIHierarchy.GetSite(out Microsoft.VisualStudio.OLE.Interop.IServiceProvider ppSP)

  </resheader>
  <resheader name="writer">
    <value>System.Resources.ResXResourceWriter, System.Windows.Forms, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089</value>
  </resheader>
  <metadata name="_splitter.GenerateMember" type="System.Boolean, mscorlib, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089">
    <value>False</value>
  </metadata>



  <metadata name="name.UserAddedColumn" type="System.Boolean, mscorlib, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089">
    <value>True</value>
  </metadata>
  <metadata name="type.UserAddedColumn" type="System.Boolean, mscorlib, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089">
    <value>True</value>
  </metadata>
  <metadata name="isnull.UserAddedColumn" type="System.Boolean, mscorlib, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089">

        Ae8BLgFhAXsBjQHlAfEBrgH4Af8BBQFCAV//AMwAAUcBkAGpAZ8B9QH/Aa4B+gH/AZIB5wHwAbEB+gH/
        AYoB6QH1AQQBSgFo/wDMAAHTAdsB3wFpAbYBygFSAZwBswE5AYABmgElAW8BkAEZAWoBjgHWAd0B4f8A
        /wD/AP8A/wD/AP8AGwABQgFNAT4HAAE+AwABKAMAAaADAAEQAwABAQEAAQEFAAFAAQEWAAP/AQAF/w8A
        Bf8PAAP/Af4BPw8AA/8B/gEfDwAD/wH+AR8PAAP/Af4BHw8AA/8B/gEfDwAD/wH8AR8PAAP/AfgBDw8A
        A/8B+AEPDwAD/wH4AQ8PAAP/AfgBDw8AA/8B+AEPDwAF/w8ABf8PAAX/DwAL
</value>
  </data>



</root>

    /// the contents of this method with the code editor.
    /// </summary>
    private void InitializeComponent()
    {
      this.components = new System.ComponentModel.Container();
      this._timer = new System.Windows.Forms.Timer(this.components);
      this._check = new System.Windows.Forms.Timer(this.components);
      this._pg = new System.Windows.Forms.PropertyGrid();
      this.SuspendLayout();
      // 
      // _timer
      // 
      this._timer.Tick += new System.EventHandler(this._timer_Tick);
      // 
      // _check
      // 
      this._check.Interval = 200;
      this._check.Tick += new System.EventHandler(this._check_Tick);
      // 
      // _pg
      // 
      this._pg.Location = new System.Drawing.Point(0, 3);
      this._pg.Name = "_pg";
      this._pg.PropertySort = System.Windows.Forms.PropertySort.NoSort;
      this._pg.Size = new System.Drawing.Size(130, 130);
      this._pg.TabIndex = 2;
      this._pg.ToolbarVisible = false;
      this._pg.Visible = false;
      // 
      // ViewDesignerDoc
      // 
      this.AutoScaleDimensions = new System.Drawing.SizeF(6F, 13F);
      this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font;
      this.Controls.Add(this._pg);
      this.Name = "ViewDesignerDoc";
      this.Size = new System.Drawing.Size(553, 407);
      this.ResumeLayout(false);

    }

    #endregion

    private System.Windows.Forms.Timer _timer;
    private System.Windows.Forms.Timer _check;
    private System.Windows.Forms.PropertyGrid _pg;
  }
}

/********************************************************
 * ADO.NET 2.0 Data Provider for SQLite Version 3.X
 * Written by Robert Simpson (robert@blackcastlesoft.com)
 * 
 * Released to the public domain, use at your own risk!
 ********************************************************/

namespace SQLite.Designer.Editors
{
  using System;
  using System.Collections.Generic;
  using System.ComponentModel;
  using System.Data;
  using System.Data.Common;

    internal bool _dirty = false;
    internal UserControl _queryDesigner;
    internal Type _typeQB;
    internal SQLite.Designer.Design.View _view;
    internal IOleCommandTarget _qbole;
    internal IOleInPlaceActiveObject _qbbase;
    private IntPtr _qbsql;
    internal DataViewHierarchyAccessor _accessor;
    internal int _itemId;
    static private bool _warned = false;

    public delegate bool EnumWindowsCallback(IntPtr hwnd, IntPtr lParam);
    [DllImport("user32.Dll")]
    public static extern bool EnumChildWindows(IntPtr parentHandle, EnumWindowsCallback callback, IntPtr lParam);

    [DllImport("user32.dll", CharSet = CharSet.Auto)]
    static extern int GetClassName(IntPtr hWnd, StringBuilder lpClassName, int nMaxCount);

    [DllImport("user32.dll", CharSet = CharSet.Auto, SetLastError = true)]
    static extern int GetWindowText(IntPtr hWnd, StringBuilder lpString, int nMaxCount);

    [DllImport("user32.dll", SetLastError = true, CharSet = CharSet.Auto)]
    static extern int GetWindowTextLength(IntPtr hWnd);

    public ViewDesignerDoc(int itemId, DataViewHierarchyAccessor accessor, string viewName)
    {
      _accessor = accessor;
      _connection = accessor.Connection;
      _itemId = itemId;
      InitializeComponent();

      _init = true;
      try
      {
        _typeQB = SQLiteDataAdapterToolboxItem._vsdesigner.GetType("Microsoft.VSDesigner.Data.Design.QueryBuilderControl");

        if (_typeQB != null)
        {
          _queryDesigner = Activator.CreateInstance(_typeQB) as UserControl;
          _typeQB.InvokeMember("Provider", System.Reflection.BindingFlags.Instance | System.Reflection.BindingFlags.SetProperty | System.Reflection.BindingFlags.NonPublic, null, _queryDesigner, new object[] { "System.Data.SQLite" });
          _typeQB.InvokeMember("ConnectionString", System.Reflection.BindingFlags.Instance | System.Reflection.BindingFlags.SetProperty | System.Reflection.BindingFlags.NonPublic, null, _queryDesigner, new object[] { _connection.ConnectionSupport.ConnectionString });
          _typeQB.InvokeMember("EnableMorphing", System.Reflection.BindingFlags.Instance | System.Reflection.BindingFlags.SetProperty | System.Reflection.BindingFlags.NonPublic, null, _queryDesigner, new object[] { false });
          Controls.Add(_queryDesigner);
          _queryDesigner.Dock = DockStyle.Fill;
          _queryDesigner.Visible = true;
        }

        StringBuilder tables = new StringBuilder();

        using (DataReader reader = _connection.Command.Execute("SELECT * FROM sqlite_master", 1, null, 30))
        {
          while (reader.Read())
          {
            tables.Append(reader.GetItem(2).ToString());
            tables.Append(",");
          }
        }

          {
            viewName = String.Format("View{0}", n);
            n++;
          } while (alltables.IndexOf(viewName + ",", StringComparison.OrdinalIgnoreCase) > -1 || _editingTables.ContainsValue(viewName));

          _editingTables.Add(GetHashCode(), viewName);
        }
        _view = new SQLite.Designer.Design.View(viewName, _connection.ConnectionSupport.ProviderObject as DbConnection, this);
      }
      finally
      {
        _init = false;
      }
    }

      }
    }

    public void NotifyChanges()
    {
      if (_serviceProvider == null) return;



      // Get a reference to the Running Document Table
      IVsRunningDocumentTable runningDocTable = (IVsRunningDocumentTable)_serviceProvider.GetService(typeof(SVsRunningDocumentTable));

      // Lock the document
      uint docCookie;
      IVsHierarchy hierarchy;
      uint itemID;

      {
        shell.UpdateDocDataIsDirtyFeedback(docCookie, (_dirty == true) ? 1 : 0);
      }

      // Unlock the document.
      // Note that we have to unlock the document even if the previous call failed.
      runningDocTable.UnlockDocument((uint)_VSRDTFLAGS.RDT_ReadLock, docCookie);


      // Check ff the call to NotifyDocChanged failed.
      //ErrorHandler.ThrowOnFailure(hr);
    }

    #region IVsPersistDocData Members

            pfSaveCanceled = 1;
            return VSConstants.S_OK;
          }
          _view.Name = dlg.TableName;
        }
      }






























      string query = _typeQB.InvokeMember("SqlText", System.Reflection.BindingFlags.NonPublic | System.Reflection.BindingFlags.Instance | System.Reflection.BindingFlags.GetProperty, null, _queryDesigner, null) as string;
      _view.SqlText = query;

      query = _view.GetSqlText();
      if (String.IsNullOrEmpty(query) == false)
      {
        using (DbTransaction trans = _view.GetConnection().BeginTransaction())

        }
      }

      _dirty = false;
      _view.Committed();
      NotifyChanges();

      SQLiteCommandHandler.Refresh(_accessor, _itemId);

      return VSConstants.S_OK;
    }

    public int SetUntitledDocPath(string pszDocDataPath)
    {
      return ((IPersistFileFormat)this).InitNew(0);
    }

    #endregion

    #region IVsWindowPane Members

    public int ClosePane()
    {












      this.Dispose(true);
      return VSConstants.S_OK;
    }

    public int CreatePaneWindow(IntPtr hwndParent, int x, int y, int cx, int cy, out IntPtr hwnd)
    {
      Win32Methods.SetParent(Handle, hwndParent);

      if (shell != null)
      {
        shell.UpdateCommandUI(1);
      }
    }





    public int SetSite(Microsoft.VisualStudio.OLE.Interop.IServiceProvider psp)
    {
      _serviceProvider = new MyServiceProvider(psp);
      System.Reflection.MethodInfo mi = _typeQB.GetMethod("Init", System.Reflection.BindingFlags.InvokeMethod | System.Reflection.BindingFlags.NonPublic | System.Reflection.BindingFlags.Instance, null, new Type[] { typeof(System.IServiceProvider), typeof(string) }, null);
      mi.Invoke(_queryDesigner, new object[] { _serviceProvider, _view.SqlText });

      _qbole = _typeQB.InvokeMember("OleCommandTarget", System.Reflection.BindingFlags.Instance | System.Reflection.BindingFlags.NonPublic | System.Reflection.BindingFlags.GetProperty, null, _queryDesigner, null) as IOleCommandTarget;

      NotifyChanges();
    }

    #region IOleCommandTarget Members

    public int Exec(ref Guid pguidCmdGroup, uint nCmdID, uint nCmdexecopt, IntPtr pvaIn, IntPtr pvaOut)
    {
      if (pguidCmdGroup == SQLiteCommandHandler.guidSQLiteCmdSet)

      {
        switch ((cmdid)nCmdID)



        {









          case cmdid.Triggers:





            ViewHolder holder = new ViewHolder(_view);
            _pg.SelectedObject = holder;
            _pg.SelectedGridItem = _pg.SelectedGridItem.Parent.GridItems[0];
            TriggerEditor ted = new TriggerEditor(_view);
            ted.EditValue((ITypeDescriptorContext)_pg.SelectedGridItem, (System.IServiceProvider)_pg.SelectedGridItem, _pg.SelectedGridItem.Value);
            return VSConstants.S_OK;




















        }
      }










      if (_qbole != null) return _qbole.Exec(ref pguidCmdGroup, nCmdID, nCmdexecopt, pvaIn, pvaOut);

      return (int)(Microsoft.VisualStudio.OLE.Interop.Constants.OLECMDERR_E_NOTSUPPORTED);
    }

    public int QueryStatus(ref Guid pguidCmdGroup, uint cCmds, OLECMD[] prgCmds, IntPtr pCmdText)
    {
      if (pguidCmdGroup == SQLiteCommandHandler.guidSQLiteCmdSet)

      {
        switch (prgCmds[0].cmdID)





        {

          case (uint)cmdid.Triggers:
            prgCmds[0].cmdf = (uint)(OLECMDF.OLECMDF_SUPPORTED | OLECMDF.OLECMDF_ENABLED);




            return VSConstants.S_OK;

        }
      }











































      int retval = (int)(Microsoft.VisualStudio.OLE.Interop.Constants.OLECMDERR_E_NOTSUPPORTED);
      
      if (_qbole != null)
        retval = _qbole.QueryStatus(ref pguidCmdGroup, cCmds, prgCmds, pCmdText);

      //if (pguidCmdGroup == SQLiteCommandHandler.guidQueryGroup)

    private void _timer_Tick(object sender, EventArgs e)
    {
      _timer.Enabled = false;
      if (_serviceProvider != null)
      {
        EnvDTE.DTE dte = (EnvDTE.DTE)_serviceProvider.GetService(typeof(EnvDTE.DTE));









        if (_qdinit == false)
        {
          _qdinit = true;
          _init = true;
          try
          {
            _typeQB.InvokeMember("PostInit", System.Reflection.BindingFlags.Instance | System.Reflection.BindingFlags.NonPublic | System.Reflection.BindingFlags.InvokeMethod, null, _queryDesigner, null);

    }

    int IVsWindowFrameNotify.OnShow(int fShow)
    {
      switch ((__FRAMESHOW)fShow)
      {
        case __FRAMESHOW.FRAMESHOW_WinShown:
        case __FRAMESHOW.FRAMESHOW_WinRestored:
          _timer.Enabled = true;
          SetPropertyWindow();
          if (_warned == false)
          {
            _warned = true;


            MessageBox.Show(this, "The view designer is still in development.  Please report bugs to robert@blackcastlesoft.com", "Feature Under Review", MessageBoxButtons.OK);
          }
          break;
      }
      return VSConstants.S_OK;
    }

    int IVsWindowFrameNotify.OnSize()
    {

    }

    protected override object GetServiceImpl(Type serviceType)
    {
      return this.GetService(serviceType.GUID);
    }
  }

  internal class ViewHolder
  {
    private List<ViewTrigger> _triggers;

    internal ViewHolder(SQLite.Designer.Design.View parent)
    {
      _triggers = parent.Triggers as List<ViewTrigger>;
    }

    public List<ViewTrigger> Triggers
    {
      get { return _triggers; }
    }
  }
}

<?xml version="1.0" encoding="utf-8"?>
<CommandTable language="en-US" xmlns="http://schemas.microsoft.com/VisualStudio/2005-10-18/CommandTable">
  <Extern href="PkgCmd.h" />
  <Commands package="guidVSPackageBasedProviderPkg">
    <Buttons>
      
      <Button guid="guidVSPackageBasedProviderCmdSet" id="cmdidVacuum" type="Button">
        <CommandFlag>DefaultInvisible</CommandFlag>
        <CommandFlag>DynamicVisibility</CommandFlag>
        <CommandFlag>DefaultDisabled</CommandFlag>
        <Strings>
          <ButtonText>&amp;Vacuum</ButtonText>
        </Strings>
      </Button>
      
      <Button guid="guidVSPackageBasedProviderCmdSet" id="cmdidRekey" type="Button">
        <CommandFlag>DefaultInvisible</CommandFlag>
        <CommandFlag>DynamicVisibility</CommandFlag>
        <CommandFlag>DefaultDisabled</CommandFlag>
        <Strings>
          <ButtonText>Change &amp;Password ...</ButtonText>
        </Strings>
      </Button>

      <Button guid="guidVSPackageBasedProviderCmdSet" id="cmdidTriggers" priority="0x0700" type="Button">
        <Icon guid="guidSharedBmps8" id="bmpid8LayoutDiagram"/>
        <CommandFlag>DynamicVisibility</CommandFlag>
        <CommandFlag>DefaultInvisible</CommandFlag>
        <CommandFlag>DefaultDisabled</CommandFlag>
        <Strings>
          <ButtonText>Manage &amp;Triggers</ButtonText>
          <ToolTipText>Manage Triggers</ToolTipText>
          <CommandName>Manage Triggers</CommandName>
        </Strings>
      </Button>

    </Buttons>
  </Commands>
  <CommandPlacements>
    <CommandPlacement guid="guidVSPackageBasedProviderCmdSet" id="cmdidVacuum" priority="0x0100">
      <Parent guid="guidVSData" id="IDG_DV_CONNECTION" />
    </CommandPlacement>
    <CommandPlacement guid="guidVSPackageBasedProviderCmdSet" id="cmdidRekey" priority="0x0100">
      <Parent guid="guidVSData" id="IDG_DV_CONNECTION" />
    </CommandPlacement>

    <CommandPlacement guid="guidVSPackageBasedProviderCmdSet" id="cmdidTriggers" priority="0x0700">
      <Parent guid="guidDavDataGrpId" id="IDG_SCH_TOOLBAR_TABLEOPS" />
    </CommandPlacement>

    <CommandPlacement guid="guidVSPackageBasedProviderCmdSet" id="cmdidTriggers" priority="0x1000">
      <Parent guid="guidDavDataGrpId" id="IDG_QRY_TOOLBAR_VIEWSHAPE" />
    </CommandPlacement>


  </CommandPlacements>  
  <Symbols>
    <GuidSymbol name="Group_Undefined" value="{83285929-227c-11d3-b870-00c04f79f802}" />
    <GuidSymbol name="Pkg_Undefined" value="{8328592a-227c-11d3-b870-00c04f79f802}" />
    <GuidSymbol name="guidVSPackageBasedProviderPkg" value="{dcbe6c8d-0e57-4099-a183-98ff74c64d9c}" />
    <GuidSymbol name="guidVSData" value="{4614107f-217d-4bbf-9dfe-b9e165c65572}">
      <IDSymbol name="IDG_DV_CONNECTION" value="0x4101" />
    </GuidSymbol>
    <GuidSymbol name="guidVSPackageBasedProviderCmdSet" value="{814658ee-a28e-4b97-bc33-4b1bc81ebecb}">
      <IDSymbol name="cmdidRekey" value="0x0107" />
      <IDSymbol name="cmdidVacuum" value="0x0106" />
      <IDSymbol name="cmdidTriggers" value="0x0108" />
    </GuidSymbol>
    <GuidSymbol name="guidOfficeIcon" value="{d309f794-903f-11d0-9efc-00a0c911004f}">
      <IDSymbol name="msotcidNoIcon" value="0x02EA" />
    </GuidSymbol>
  </Symbols>
</CommandTable>

#ifndef _PKGCMDS_
#define _PKGCMDS_

#define guidSharedBmps8                             {2b671d3d-ab51-434a-8d38-cbf1728530bb}
#define guidDavDataGrpId                            {732abe74-cd80-11d0-a2db-00aa00a3efff}
#define GUID_Mode_TableDesigner                     {4194fee5-6777-419f-a5fc-47a536df1bdb}

#define bmpid8LayoutDiagram                         0x0004
#define IDG_SCH_TOOLBAR_TABLEOPS                    0x1110
#define IDG_QRY_TOOLBAR_VIEWSHAPE                   0x1012

#endif

    <DebugSymbols>true</DebugSymbols>
    <DebugType>full</DebugType>
    <Optimize>false</Optimize>
    <OutputPath>..\bin\designer\</OutputPath>
    <DefineConstants>DEBUG;TRACE</DefineConstants>
    <ErrorReport>prompt</ErrorReport>
    <WarningLevel>4</WarningLevel>
    <NoWarn>1701;1702;1699;3001</NoWarn>
    <FileAlignment>512</FileAlignment>
    <PlatformTarget>x86</PlatformTarget>
    <AllowUnsafeBlocks>false</AllowUnsafeBlocks>
    <RegisterOutputPackage>false</RegisterOutputPackage>
    <GeneratePkgDefFile>false</GeneratePkgDefFile>
    <RegisterWithCodebase>false</RegisterWithCodebase>
  </PropertyGroup>
  <PropertyGroup Condition=" '$(Configuration)|$(Platform)' == 'Release|AnyCPU' ">
    <DebugType>none</DebugType>
    <Optimize>true</Optimize>
    <OutputPath>..\bin\Designer\</OutputPath>
    <DefineConstants>
    </DefineConstants>
    <ErrorReport>prompt</ErrorReport>
    <WarningLevel>4</WarningLevel>
    <NoWarn>1701;1702;1699;3001</NoWarn>
    <FileAlignment>512</FileAlignment>
    <PlatformTarget>x86</PlatformTarget>
    <AllowUnsafeBlocks>false</AllowUnsafeBlocks>
    <RegisterOutputPackage>false</RegisterOutputPackage>
    <RegisterWithCodebase>false</RegisterWithCodebase>
    <GeneratePkgDefFile>false</GeneratePkgDefFile>
  </PropertyGroup>

  <ItemGroup>
    <Compile Include="ChangePasswordDialog.cs">
      <SubType>Form</SubType>
    </Compile>
    <Compile Include="ChangePasswordDialog.Designer.cs">
      <DependentUpon>ChangePasswordDialog.cs</DependentUpon>
    </Compile>
    <Compile Include="ChangeScriptDialog.cs">
      <SubType>Form</SubType>
    </Compile>
    <Compile Include="ChangeScriptDialog.Designer.cs">
      <DependentUpon>ChangeScriptDialog.cs</DependentUpon>
    </Compile>
    <Compile Include="Design\Check.cs" />
    <Compile Include="Design\Column.cs" />
    <Compile Include="Design\ForeignKey.cs" />
    <Compile Include="Design\Index.cs" />
    <Compile Include="Design\PrimaryKey.cs" />
    <Compile Include="Design\SimpleTokenizer.cs" />
    <Compile Include="Design\Table.cs" />
    <Compile Include="Design\Trigger.cs" />
    <Compile Include="Design\Unique.cs" />
    <Compile Include="Design\View.cs" />
    <Compile Include="Editors\AutoCompleteColumn.cs">
      <SubType>Component</SubType>
    </Compile>
    <Compile Include="Editors\TableDesignerDoc.cs">
      <SubType>UserControl</SubType>

    </EmbeddedResource>
    <EmbeddedResource Include="SQLiteDataObjectSupport.xml" />
    <EmbeddedResource Include="TableNameDialog.resx">
      <DependentUpon>TableNameDialog.cs</DependentUpon>
    </EmbeddedResource>
  </ItemGroup>
  <ItemGroup>
    <EmbeddedResource Include="ChangeScriptDialog.resx">
      <DependentUpon>ChangeScriptDialog.cs</DependentUpon>
    </EmbeddedResource>
    <EmbeddedResource Include="SQLiteDataViewSupport2005.xml" />
  </ItemGroup>
  <ItemGroup>
    <None Include="Resources\info.png" />
  </ItemGroup>
  <ItemGroup>
    <Folder Include="Properties\" />
  </ItemGroup>
  <Import Project="$(MSBuildBinPath)\Microsoft.CSharp.targets" />
  <Import Project="$(MSBuildExtensionsPath)\Microsoft\VisualStudio\v9.0\VSSDK\Microsoft.VsSDK.targets" />
  <PropertyGroup>
    <PostBuildEvent>
    </PostBuildEvent>
  </PropertyGroup>
</Project>

  using SQLite.Designer.Editors;

  enum cmdid
  {
    CreateTable = 0x3520,
    CreateView = 0x3521,
    Alter = 0x3003,
    Refresh = 0x3004,
    Delete = 17,
    Vacuum = 262,
    Rekey = 263,
    Triggers = 264,
  }

  internal sealed class SQLiteCommandHandler : DataViewCommandHandler
  {
    internal static readonly Guid guidDataCmdSet = new Guid("501822E1-B5AF-11d0-B4DC-00A0C91506EF");
    internal static readonly Guid guidSQLiteCmdSet = new Guid("814658EE-A28E-4b97-BC33-4B1BC81EBECB");
    internal static readonly Guid guidIFCmdId = new Guid("{74d21311-2aee-11d1-8bfb-00a0c90f26f7}");
    internal static readonly Guid guidDavinci = new Guid("{732abe75-cd80-11d0-a2db-00aa00a3efff}");
    internal static readonly Guid guidDavinciGrp = new Guid("{732abe74-cd80-11d0-a2db-00aa00a3efff}");
    internal static readonly Guid guidQueryGroup = new Guid("5efc7975-14bc-11cf-9b2b-00aa00573819");
    internal static Guid guidTableDesignContext = new Guid("4194fee5-6777-419f-a5fc-47a536df1bdb");
    internal static Guid guidViewDesignContext = new Guid("b968e165-98e0-41f0-8fbe-a8ed1d246a90");

    public SQLiteCommandHandler()
    {
    }

    public override OleCommandStatus GetCommandStatus(int[] itemIds, OleCommand command, OleCommandTextType textType, OleCommandStatus status)
    {

      Microsoft.VisualStudio.OLE.Interop.IServiceProvider provider = DataViewHierarchyAccessor.ServiceProvider as Microsoft.VisualStudio.OLE.Interop.IServiceProvider;
      IVsUIShell shell = DataViewHierarchyAccessor.ServiceProvider.GetService(typeof(IVsUIShell)) as IVsUIShell;
      IVsUIHierarchy hier = DataViewHierarchyAccessor.Hierarchy;
      IVsWindowFrame frame;

      if (shell != null)
      {
        TableDesignerDoc form = new TableDesignerDoc(itemId, DataViewHierarchyAccessor, tableName);
        IntPtr formptr = System.Runtime.InteropServices.Marshal.GetIUnknownForObject(form);
        Guid empty = Guid.Empty;
        FakeHierarchy fake = new FakeHierarchy(form, hier);

        int code = shell.CreateDocumentWindow(
          0, // (uint)(__VSCREATEDOCWIN.CDW_fCreateNewWindow | __VSCREATEDOCWIN.CDW_RDTFLAGS_MASK) | (uint)(_VSRDTFLAGS.RDT_CanBuildFromMemory | _VSRDTFLAGS.RDT_NonCreatable | _VSRDTFLAGS.RDT_VirtualDocument | _VSRDTFLAGS.RDT_DontAddToMRU),
          form.Name, fake, (uint)itemId, formptr, formptr, ref empty, null, ref guidTableDesignContext, provider, "", form.Caption, null, out frame);

        if (frame != null)
        {
          object ret;
          int prop = (int)__VSFPROPID.VSFPROPID_Caption;
          
          code = frame.GetProperty(prop, out ret);

      Microsoft.VisualStudio.OLE.Interop.IServiceProvider provider = DataViewHierarchyAccessor.ServiceProvider as Microsoft.VisualStudio.OLE.Interop.IServiceProvider;
      IVsUIShell shell = DataViewHierarchyAccessor.ServiceProvider.GetService(typeof(IVsUIShell)) as IVsUIShell;
      IVsUIHierarchy hier = DataViewHierarchyAccessor.Hierarchy;
      IVsWindowFrame frame;

      if (shell != null)
      {
        ViewDesignerDoc form = new ViewDesignerDoc(itemId, DataViewHierarchyAccessor, viewName);
        IntPtr formptr = System.Runtime.InteropServices.Marshal.GetIUnknownForObject(form);
        Guid empty = Guid.Empty;
        FakeHierarchy fake = new FakeHierarchy(form, hier);

        int code = shell.CreateDocumentWindow(
          0, // (uint)(__VSCREATEDOCWIN.CDW_fCreateNewWindow | __VSCREATEDOCWIN.CDW_RDTFLAGS_MASK) | (uint)(_VSRDTFLAGS.RDT_CanBuildFromMemory | _VSRDTFLAGS.RDT_NonCreatable | _VSRDTFLAGS.RDT_VirtualDocument | _VSRDTFLAGS.RDT_DontAddToMRU),
          form.Name, fake, (uint)itemId, formptr, formptr, ref empty, null, ref guidViewDesignContext, provider, "", form.Caption, null, out frame);

        if (frame != null)
        {
          object ret;
          int prop = (int)__VSFPROPID.VSFPROPID_Caption;

          code = frame.GetProperty(prop, out ret);

            Refresh(itemId);
          }
        }
      }
    }

    public void Refresh(int itemId)
    {
      Refresh(DataViewHierarchyAccessor, itemId);
    }

    public static void Refresh(DataViewHierarchyAccessor accessor, int itemId)
    {
      IVsUIHierarchy hier = accessor.Hierarchy as IVsUIHierarchy;
      Guid g = VSConstants.GUID_VSStandardCommandSet97;
      hier.ExecCommand((uint)itemId, ref g, (uint)0xbd, (uint)OleCommandExecutionOption.DoDefault, IntPtr.Zero, IntPtr.Zero);
    }
  }
}

        case "view":
          length = 3;
          break;
        case "column":
        case "index":
        case "foreignkey":
        case "viewcolumn":
        case "triggers":
          length = 4;
          break;
        case "indexcolumn":
        case "foreignkeycolumn":
          length = 5;
          break;
        default:

				<Property name="Name" type="System.String" itemName="column_name"/>
				<Property name="Ordinal" type="System.Int32" itemName="ordinal_position">
					<Concepts>
						<Concept name="Ordinal">
						</Concept>
					</Concepts>
				</Property>
        <Property name="DataType" type="System.String" itemName="data_type" />
        <Property name="SystemType" type="System.String" itemName="data_type">
          <Concepts>
            <Concept name="UserDataType"/>
            <Concept name="NativeDataType"/>
            <Concept name="ProviderDataType">
              <Conversion mapper="Microsoft.VisualStudio.Data.AdoDotNet.AdoDotNetObjectConceptMapper"/>
            </Concept>

              </Parameter>
            </Parameter>
          </Parameter>
        </Action>
      </Actions>
    </Type>

    <Type name="Triggers" defaultSort="Database,Table,Name">
      <Concepts>
        <Concept name="TableTriggers" restrictions="{Catalog},null,{Table},{Name}"/>
      </Concepts>
      <Identifier>
        <Part name="Database" itemName="table_catalog">
          <Concepts>
            <Concept name="Identifier0"/>
          </Concepts>
        </Part>
        <Part name="Schema" itemName="table_schema">
          <Concepts>
            <Concept name="Identifier1"/>
          </Concepts>
        </Part>
        <Part name="Table" itemName="table_name">
          <Concepts>
            <Concept name="Identifier2"/>
          </Concepts>
        </Part>
        <Part name="Name" itemName="trigger_name">
          <Concepts>
            <Concept name="Identifier3"/>
          </Concepts>
        </Part>
      </Identifier>
      <Properties>
        <Property name="Name" type="System.String" itemName="trigger_name"/>
      </Properties>
      <Actions>
        <Action name="Enumerate" guid="61CC0372-384D-42e5-9707-6D7C8DC5287A" handler="Microsoft.VisualStudio.Data.AdoDotNet.AdoDotNetObjectEnumerator">
          <Parameter value="Triggers"/>
        </Action>
      </Actions>
    </Type>
    
    <Type name="ForeignKey" defaultSort="Database,Table,Name">
      <Concepts>
        <Concept name="TableForeignKey" restrictions="{Catalog},null,{Table},{Name}"/>
      </Concepts>
      <Identifier>
        <Part name="Database" itemName="table_catalog">
          <Concepts>

            </CommandBindings>
						<Children>
							<Selection type="View">
								<SelectionNode nid="View">
                  <DisplayName>{View.Name}</DisplayName>
                  <Icon name="View"/>
									<Children>


                    <SubHierarchyRef name="View children"/>


									</Children>
								</SelectionNode>
							</Selection>
						</Children>
					</StaticNode>
                  
        </Children>
			</StaticConnectionNode>
		</DataView>
	</DataViews>
  <SubHierarchies>
    <SubHierarchy name="table children">      
      <StaticNode nid="Columns">
        <DisplayName>Columns</DisplayName>

          <Selection type="ForeignKey" restrictions="{Table.Database},null,{Table.Name}">
            <SelectionNode>
              <Icon name="ForeignKey"/>
            </SelectionNode>
          </Selection>
        </Children>
      </StaticNode>

      <StaticNode nid="Triggers">
        <DisplayName>Triggers</DisplayName>
        <Children>
          <Selection type="Triggers" restrictions="{Table.Database},null,{Table.Name}">
            <SelectionNode>
              <Icon name="Index" />
            </SelectionNode>
          </Selection>
        </Children>
      </StaticNode>
    </SubHierarchy>
    <SubHierarchy name="view children">      
      <StaticNode nid="Columns">
        <DisplayName>Columns</DisplayName>
        <CommandBindings>
          <CommandBinding name="NewQuery" guid="501822E1-B5AF-11d0-B4DC-00A0C91506EF" cmdid="13608" handler="884DD964-5327-461f-9F06-6484DD540F8F"/>
        </CommandBindings>
        <Children>
          <Selection type="ViewColumn" restrictions="{View.Database},null,{View.Name}">
            <SelectionNode>
              <Icon name="Column"/>
            </SelectionNode>
          </Selection>
        </Children>
      </StaticNode>
      
      <StaticNode nid="Triggers">
        <DisplayName>Triggers</DisplayName>
        <Children>
          <Selection type="Triggers" restrictions="{View.Database},null,{View.Name}">
            <SelectionNode>
              <Icon name="Index" />
            </SelectionNode>
          </Selection>
        </Children>
      </StaticNode>
    </SubHierarchy>
  </SubHierarchies>
  <TypeExtensions>
    
    <TypeExtension name="Table">
      <Identifier>
        <Part name="Name">

    
    <TypeExtension name="ViewColumn">
      <Identifier>
        <Part name="Name">
          <Category resource="Category_Identity"/>
        </Part>
        <Part name="Database">
          <DisplayName>Catalog</DisplayName>
          <Category resource="Category_Location"/>
        </Part>
        <Part name="View">
          <Category resource="Category_Location"/>
        </Part>
      </Identifier>
      <Properties>
        <Property name="Ordinal"/>
        <Property name="Length"/>
        <Property name="DataType">
          <DisplayName>Data Type</DisplayName>
        </Property>
        <Property name="Nullable">
          <DisplayName>Allow Nulls</DisplayName>
        </Property>
        <Property name="Default">

      <CommandBindings>
        <CommandBinding name="NewQuery" guid="501822E1-B5AF-11d0-B4DC-00A0C91506EF" cmdid="13608" handler="884DD964-5327-461f-9F06-6484DD540F8F"/>
        <CommandBinding name="DropIndex" guid="5efc7975-14bc-11cf-9b2b-00aa00573819" cmdid="17" handler="SQLite.Designer.SQLiteCommandHandler">
          <Parameter value="Index"/>
        </CommandBinding>
      </CommandBindings>
    </TypeExtension>

    <TypeExtension name="Triggers">
      <Identifier>
        <Part name="Name">
          <Category resource="Category_Identity"/>
        </Part>
        <Part name="Database">
          <DisplayName>Catalog</DisplayName>
          <Category resource="Category_Location"/>
        </Part>
        <Part name="Table">
          <Category resource="Category_Location"/>
        </Part>
      </Identifier>
    </TypeExtension>

    <TypeExtension name="TableColumn">
      <Identifier>
        <Part name="Name">
          <Category resource="Category_Identity"/>
        </Part>
        <Part name="Database">

            </CommandBindings>
						<Children>
							<Selection type="View">
								<SelectionNode nid="View">
                  <DisplayName>{View.Name}</DisplayName>
                  <Icon name="View"/>
									<Children>


                    <SubHierarchyRef name="View children"/>


									</Children>
								</SelectionNode>
							</Selection>
						</Children>
					</StaticNode>   
          
				</Children>
			</StaticConnectionNode>
		</DataView>
	</DataViews>
  
  <SubHierarchies>
    <SubHierarchy name="table children">      
      <StaticNode nid="Columns">
        <DisplayName>Columns</DisplayName>
        <CommandBindings>
          <CommandBinding name="NewQuery" guid="501822E1-B5AF-11d0-B4DC-00A0C91506EF" cmdid="13608" handler="884DD964-5327-461f-9F06-6484DD540F8F"/>
        </CommandBindings>

          <Selection type="ForeignKey" restrictions="{Table.Database},null,{Table.Name}">
            <SelectionNode>
              <Icon name="ForeignKey"/>
            </SelectionNode>
          </Selection>
        </Children>
      </StaticNode>

      <StaticNode nid="Triggers">
        <DisplayName>Triggers</DisplayName>
        <Children>
          <Selection type="Triggers" restrictions="{Table.Database},null,{Table.Name}">
            <SelectionNode>
              <Icon name="Index" />
            </SelectionNode>
          </Selection>
        </Children>
      </StaticNode>
    </SubHierarchy>
    
    <SubHierarchy name="view children">      
      <StaticNode nid="Columns">
        <DisplayName>Columns</DisplayName>
        <CommandBindings>
          <CommandBinding name="NewQuery" guid="501822E1-B5AF-11d0-B4DC-00A0C91506EF" cmdid="13608" handler="884DD964-5327-461f-9F06-6484DD540F8F"/>
        </CommandBindings>
        <Children>
          <Selection type="ViewColumn" restrictions="{View.Database},null,{View.Name}">
            <SelectionNode>
              <Icon name="Column"/>
            </SelectionNode>
          </Selection>
        </Children>
      </StaticNode>
      
      <StaticNode nid="Triggers">
        <DisplayName>Triggers</DisplayName>
        <Children>
          <Selection type="Triggers" restrictions="{View.Database},null,{View.Name}">
            <SelectionNode>
              <Icon name="Index" />
            </SelectionNode>
          </Selection>
        </Children>
      </StaticNode>
    </SubHierarchy>
    
  </SubHierarchies>
  <TypeExtensions>
    
    <TypeExtension name="Table">
      <Identifier>
        <Part name="Name">
          <Category resource="Category_Identity"/>

    
    <TypeExtension name="ViewColumn">
      <Identifier>
        <Part name="Name">
          <Category resource="Category_Identity"/>
        </Part>
        <Part name="Database">
          <DisplayName>Catalog</DisplayName>
          <Category resource="Category_Location"/>
        </Part>
        <Part name="View">
          <Category resource="Category_Location"/>
        </Part>
      </Identifier>
      <Properties>
        <Property name="Ordinal"/>
        <Property name="Length"/>
        <Property name="DataType">
          <DisplayName>Data Type</DisplayName>
        </Property>
        <Property name="Nullable">
          <DisplayName>Allow Nulls</DisplayName>
        </Property>
        <Property name="Default">

      <CommandBindings>
        <CommandBinding name="NewQuery" guid="501822E1-B5AF-11d0-B4DC-00A0C91506EF" cmdid="13608" handler="884DD964-5327-461f-9F06-6484DD540F8F"/>
        <CommandBinding name="DropIndex" guid="5efc7975-14bc-11cf-9b2b-00aa00573819" cmdid="17" handler="SQLite.Designer.SQLiteCommandHandler">
          <Parameter value="Index"/>
        </CommandBinding>
      </CommandBindings>
    </TypeExtension>

    <TypeExtension name="Triggers">
      <Identifier>
        <Part name="Name">
          <Category resource="Category_Identity"/>
        </Part>
        <Part name="Database">
          <DisplayName>Catalog</DisplayName>
          <Category resource="Category_Location"/>
        </Part>
        <Part name="Table">
          <Category resource="Category_Location"/>
        </Part>
      </Identifier>
    </TypeExtension>

    <TypeExtension name="TableColumn">
      <Identifier>
        <Part name="Name">
          <Category resource="Category_Identity"/>
        </Part>
        <Part name="Database">

      this.Controls.Add(this.label1);
      this.Controls.Add(_cancel);
      this.Controls.Add(_ok);
      this.FormBorderStyle = System.Windows.Forms.FormBorderStyle.FixedDialog;
      this.MaximizeBox = false;
      this.MinimizeBox = false;
      this.Name = "TableNameDialog";
      this.Font = new System.Drawing.Font("MS Shell Dlg 2", 8.25F, System.Drawing.FontStyle.Regular, System.Drawing.GraphicsUnit.Point, ((byte)(0)));
      this.StartPosition = System.Windows.Forms.FormStartPosition.CenterParent;
      this.Text = "% Name";
      this.ResumeLayout(false);
      this.PerformLayout();

    }

/********************************************************
 * ADO.NET 2.0 Data Provider for SQLite Version 3.X
 * Written by Robert Simpson (robert@blackcastlesoft.com)

 * 
 * Released to the public domain, use at your own risk!


 ********************************************************/

namespace SQLite.Designer
{
  using System;
  using System.Collections.Generic;
  using System.ComponentModel;
  using System.Data;
  using System.Drawing;
  using System.Text;
  using System.Windows.Forms;

  public partial class TableNameDialog : Form
  {
    public TableNameDialog()
      : this("Table", null)
    {
    }

//------------------------------------------------------------------------------
// <auto-generated>
//     This code was generated by a tool.
//     Runtime Version:2.0.50727.3031
//
//     Changes to this file may cause incorrect behavior and will be lost if
//     the code is regenerated.
// </auto-generated>
//------------------------------------------------------------------------------

namespace SQLite.Designer {

        ///   Looks up a localized string similar to The database and its metadata will be encrypted using the supplied password as a hash..
        /// </summary>
        internal static string Encrypt {
            get {
                return ResourceManager.GetString("Encrypt", resourceCulture);
            }
        }
        
        internal static System.Drawing.Bitmap info {
            get {
                object obj = ResourceManager.GetObject("info", resourceCulture);
                return ((System.Drawing.Bitmap)(obj));
            }
        }
        
        /// <summary>
        ///   Looks up a localized string similar to The database and its metadata will be re-encrypted using the supplied password as a hash..
        /// </summary>
        internal static string ReEncrypt {
            get {
                return ResourceManager.GetString("ReEncrypt", resourceCulture);
            }
        }
    }
}

  </resheader>
  <resheader name="reader">
    <value>System.Resources.ResXResourceReader, System.Windows.Forms, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089</value>
  </resheader>
  <resheader name="writer">
    <value>System.Resources.ResXResourceWriter, System.Windows.Forms, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089</value>
  </resheader>



  <data name="Decrypt" xml:space="preserve">
    <value>The database and its metadata will be un-encrypted.  No password will be required to open the database and view its contents.</value>
  </data>
  <data name="Encrypt" xml:space="preserve">
    <value>The database and its metadata will be encrypted using the supplied password as a hash.</value>
  </data>
  <data name="ReEncrypt" xml:space="preserve">
    <value>The database and its metadata will be re-encrypted using the supplied password as a hash.</value>
  </data>
  <data name="400" xml:space="preserve">
    <value>MHM2ZQETQKDTJEPTC1MTQCZ1R1KQEMAPZHETDZPZI9RPJ0E0DHAHKCHZPKQ8AQZICADHKIZ1JAQED8IDEHZPZKZEIKAQERHPRCQMAMRKDEZZQRDRDHJEZIKECZPDIIKC</value>
  </data>
  <assembly alias="System.Windows.Forms" name="System.Windows.Forms, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" />
  <data name="info" type="System.Resources.ResXFileRef, System.Windows.Forms">
    <value>Resources\info.png;System.Drawing.Bitmap, System.Drawing, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a</value>
  </data>
</root>

/////////////////////////////////////////////////////////////////////////////
//
// Version
//

VS_VERSION_INFO VERSIONINFO
 FILEVERSION 1,0,53,0
 PRODUCTVERSION 1,0,0,0
 FILEFLAGSMASK 0x17L
#ifdef _DEBUG
 FILEFLAGS 0x1L
#else
 FILEFLAGS 0x0L
#endif
 FILEOS 0x4L
 FILETYPE 0x2L
 FILESUBTYPE 0x0L
BEGIN
    BLOCK "StringFileInfo"
    BEGIN
        BLOCK "040904b0"
        BEGIN
            VALUE "Comments", "http://sqlite.phxsoftware.com"
            VALUE "FileDescription", "System.Data.SQLite Interop Library"
            VALUE "FileVersion", "1.0.53.0"
            VALUE "InternalName", "SQLite.Interop.DLL"
            VALUE "LegalCopyright", "Released to the public domain"
            VALUE "OriginalFilename", "SQLite3.DLL 3.6.0"
            VALUE "ProductName", "System.Data.SQLite"
            VALUE "ProductVersion", "1.0"
        END
    END

{
  sqlite3_free(z);
}

__declspec(dllexport) int WINAPI sqlite3_open_interop(const char*filename, sqlite3 **ppdb)
{
  int ret = sqlite3_open(filename, ppdb);
  if (!ret) sqlite3_enable_load_extension(*ppdb, 1);
  return ret;
}

__declspec(dllexport) int WINAPI sqlite3_open16_interop(const void *filename, sqlite3 **ppdb)
{
  int ret = sqlite3_open16(filename, ppdb);
  if (!ret) sqlite3_enable_load_extension(*ppdb, 1);
  return ret;
}

__declspec(dllexport) int WINAPI sqlite3_errcode_interop(sqlite3 *db)
{
  return sqlite3_errcode(db);
}

// This code was automatically generated from assembly
// C:\Src\SQLite.NET\System.Data.SQLite\bin\CompactFramework\System.Data.SQLite.dll

#include <windef.h>

#pragma data_seg(push,clrseg,".clr")
#pragma comment(linker, "/SECTION:.clr,ER")
  char __ph[138636] = {0}; // The number of bytes to reserve
#pragma data_seg(pop,clrseg)

typedef BOOL (WINAPI *DLLMAIN)(HANDLE, DWORD, LPVOID);
typedef struct EXTRA_STUFF
{
  DWORD dwNativeEntryPoint;
} EXTRA_STUFF, *LPEXTRA_STUFF;

// This code was automatically generated from assembly
// C:\Src\SQLite.NET\System.Data.SQLite\bin\System.Data.SQLite.dll

#include <windef.h>

#pragma data_seg(push,clrseg,".clr")
#pragma comment(linker, "/SECTION:.clr,ER")
  char __ph[151004] = {0}; // The number of bytes to reserve
#pragma data_seg(pop,clrseg)

typedef BOOL (WINAPI *DLLMAIN)(HANDLE, DWORD, LPVOID);
typedef struct EXTRA_STUFF
{
  DWORD dwNativeEntryPoint;
} EXTRA_STUFF, *LPEXTRA_STUFF;

//---------------------------------------------------------------------
// <copyright file="SqlGenerator.cs" company="Microsoft">
//      Copyright (c) Microsoft Corporation.  All rights reserved.
// </copyright>
//---------------------------------------------------------------------

using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.Globalization;
using System.IO;
using System.Text;
using System.Data.Common;
using System.Data.Metadata.Edm;
using System.Data.Common.CommandTrees;
using System.Data;


namespace System.Data.SQLite
{
  /// <summary>
  /// Translates the command object into a SQL string that can be executed on
  /// SQL Server 2005.
  /// </summary>
  /// <remarks>
  /// The translation is implemented as a visitor <see cref="DbExpressionVisitor{T}"/>
  /// over the query tree.  It makes a single pass over the tree, collecting the sql
  /// fragments for the various nodes in the tree <see cref="ISqlFragment"/>.
  ///
  /// The major operations are
  /// <list type="bullet">
  /// <item>Select statement minimization.  Multiple nodes in the query tree
  /// that can be part of a single SQL select statement are merged. e.g. a
  /// Filter node that is the input of a Project node can typically share the
  /// same SQL statement.</item>
  /// <item>Alpha-renaming.  As a result of the statement minimization above, there
  /// could be name collisions when using correlated subqueries
  /// <example>
  /// <code>
  /// Filter(
  ///     b = Project( c.x
  ///         c = Extent(foo)
  ///         )
  ///     exists (
  ///         Filter(
  ///             c = Extent(foo)
  ///             b.x = c.x
  ///             )
  ///     )
  /// )
  /// </code>
  /// The first Filter, Project and Extent will share the same SQL select statement.
  /// The alias for the Project i.e. b, will be replaced with c.
  /// If the alias c for the Filter within the exists clause is not renamed,
  /// we will get <c>c.x = c.x</c>, which is incorrect.
  /// Instead, the alias c within the second filter should be renamed to c1, to give
  /// <c>c.x = c1.x</c> i.e. b is renamed to c, and c is renamed to c1.
  /// </example>
  /// </item>
  /// <item>Join flattening.  In the query tree, a list of join nodes is typically
  /// represented as a tree of Join nodes, each with 2 children. e.g.
  /// <example>
  /// <code>
  /// a = Join(InnerJoin
  ///     b = Join(CrossJoin
  ///         c = Extent(foo)
  ///         d = Extent(foo)
  ///         )
  ///     e = Extent(foo)
  ///     on b.c.x = e.x
  ///     )
  /// </code>
  /// If translated directly, this will be translated to
  /// <code>
  /// FROM ( SELECT c.*, d.*
  ///         FROM foo as c
  ///         CROSS JOIN foo as d) as b
  /// INNER JOIN foo as e on b.x' = e.x
  /// </code>
  /// It would be better to translate this as
  /// <code>
  /// FROM foo as c
  /// CROSS JOIN foo as d
  /// INNER JOIN foo as e on c.x = e.x
  /// </code>
  /// This allows the optimizer to choose an appropriate join ordering for evaluation.
  /// </example>
  /// </item>
  /// <item>Select * and column renaming.  In the example above, we noticed that
  /// in some cases we add <c>SELECT * FROM ...</c> to complete the SQL
  /// statement. i.e. there is no explicit PROJECT list.
  /// In this case, we enumerate all the columns available in the FROM clause
  /// This is particularly problematic in the case of Join trees, since the columns
  /// from the extents joined might have the same name - this is illegal.  To solve
  /// this problem, we will have to rename columns if they are part of a SELECT *
  /// for a JOIN node - we do not need renaming in any other situation.
  /// <see cref="SqlGenerator.AddDefaultColumns"/>.
  /// </item>
  /// </list>
  ///
  /// <para>
  /// Renaming issues.
  /// When rows or columns are renamed, we produce names that are unique globally
  /// with respect to the query.  The names are derived from the original names,
  /// with an integer as a suffix. e.g. CustomerId will be renamed to CustomerId1,
  /// CustomerId2 etc.
  ///
  /// Since the names generated are globally unique, they will not conflict when the
  /// columns of a JOIN SELECT statement are joined with another JOIN. 
  ///
  /// </para>
  ///
  /// <para>
  /// Record flattening.
  /// SQL server does not have the concept of records.  However, a join statement
  /// produces records.  We have to flatten the record accesses into a simple
  /// <c>alias.column</c> form.  <see cref="SqlGenerator.Visit(DbPropertyExpression)"/>
  /// </para>
  ///
  /// <para>
  /// Building the SQL.
  /// There are 2 phases
  /// <list type="numbered">
  /// <item>Traverse the tree, producing a sql builder <see cref="SqlBuilder"/></item>
  /// <item>Write the SqlBuilder into a string, renaming the aliases and columns
  /// as needed.</item>
  /// </list>
  ///
  /// In the first phase, we traverse the tree.  We cannot generate the SQL string
  /// right away, since
  /// <list type="bullet">
  /// <item>The WHERE clause has to be visited before the from clause.</item>
  /// <item>extent aliases and column aliases need to be renamed.  To minimize
  /// renaming collisions, all the names used must be known, before any renaming
  /// choice is made.</item>
  /// </list>
  /// To defer the renaming choices, we use symbols <see cref="Symbol"/>.  These
  /// are renamed in the second phase.
  ///
  /// Since visitor methods cannot transfer information to child nodes through
  /// parameters, we use some global stacks,
  /// <list type="bullet">
  /// <item>A stack for the current SQL select statement.  This is needed by
  /// <see cref="SqlGenerator.Visit(DbVariableReferenceExpression)"/> to create a
  /// list of free variables used by a select statement.  This is needed for
  /// alias renaming.
  /// </item>
  /// <item>A stack for the join context.  When visiting a <see cref="DbScanExpression"/>,
  /// we need to know whether we are inside a join or not.  If we are inside
  /// a join, we do not create a new SELECT statement.</item>
  /// </list>
  /// </para>
  ///
  /// <para>
  /// Global state.
  /// To enable renaming, we maintain
  /// <list type="bullet">
  /// <item>The set of all extent aliases used.</item>
  /// <item>The set of all column aliases used.</item>
  /// </list>
  ///
  /// Finally, we have a symbol table to lookup variable references.  All references
  /// to the same extent have the same symbol.
  /// </para>
  ///
  /// <para>
  /// Sql select statement sharing.
  ///
  /// Each of the relational operator nodes
  /// <list type="bullet">
  /// <item>Project</item>
  /// <item>Filter</item>
  /// <item>GroupBy</item>
  /// <item>Sort/OrderBy</item>
  /// </list>
  /// can add its non-input (e.g. project, predicate, sort order etc.) to
  /// the SQL statement for the input, or create a new SQL statement.
  /// If it chooses to reuse the input's SQL statement, we play the following
  /// symbol table trick to accomplish renaming.  The symbol table entry for
  /// the alias of the current node points to the symbol for the input in
  /// the input's SQL statement.
  /// <example>
  /// <code>
  /// Project(b.x
  ///     b = Filter(
  ///         c = Extent(foo)
  ///         c.x = 5)
  ///     )
  /// </code>
  /// The Extent node creates a new SqlSelectStatement.  This is added to the
  /// symbol table by the Filter as {c, Symbol(c)}.  Thus, <c>c.x</c> is resolved to
  /// <c>Symbol(c).x</c>.
  /// Looking at the project node, we add {b, Symbol(c)} to the symbol table if the
  /// SQL statement is reused, and {b, Symbol(b)}, if there is no reuse.
  ///
  /// Thus, <c>b.x</c> is resolved to <c>Symbol(c).x</c> if there is reuse, and to
  /// <c>Symbol(b).x</c> if there is no reuse.
  /// </example>
  /// </para>
  /// </remarks>
  internal sealed class SqlGenerator : DbExpressionVisitor<ISqlFragment>
  {
    #region Visitor parameter stacks
    /// <summary>
    /// Every relational node has to pass its SELECT statement to its children
    /// This allows them (DbVariableReferenceExpression eventually) to update the list of
    /// outer extents (free variables) used by this select statement.
    /// </summary>
    Stack<SqlSelectStatement> selectStatementStack;

    /// <summary>
    /// The top of the stack
    /// </summary>
    private SqlSelectStatement CurrentSelectStatement
    {
      // There is always something on the stack, so we can always Peek.
      get { return selectStatementStack.Peek(); }
    }

    /// <summary>
    /// Nested joins and extents need to know whether they should create
    /// a new Select statement, or reuse the parent's.  This flag
    /// indicates whether the parent is a join or not.
    /// </summary>
    Stack<bool> isParentAJoinStack;

    /// <summary>
    /// The top of the stack
    /// </summary>
    private bool IsParentAJoin
    {
      // There might be no entry on the stack if a Join node has never
      // been seen, so we return false in that case.
      get { return isParentAJoinStack.Count == 0 ? false : isParentAJoinStack.Peek(); }
    }

    #endregion

    #region Global lists and state
    Dictionary<string, int> allExtentNames;
    internal Dictionary<string, int> AllExtentNames
    {
      get { return allExtentNames; }
    }

    // For each column name, we store the last integer suffix that
    // was added to produce a unique column name.  This speeds up
    // the creation of the next unique name for this column name.
    Dictionary<string, int> allColumnNames;
    internal Dictionary<string, int> AllColumnNames
    {
      get { return allColumnNames; }
    }

    SymbolTable symbolTable = new SymbolTable();

    /// <summary>
    /// VariableReferenceExpressions are allowed only as children of DbPropertyExpression
    /// or MethodExpression.  The cheapest way to ensure this is to set the following
    /// property in DbVariableReferenceExpression and reset it in the allowed parent expressions.
    /// </summary>
    bool isVarRefSingle = false;

    #endregion

    #region Statics
    static private readonly Dictionary<string, FunctionHandler> _builtInFunctionHandlers = InitializeBuiltInFunctionHandlers();
    static private readonly Dictionary<string, FunctionHandler> _canonicalFunctionHandlers = InitializeCanonicalFunctionHandlers();
    static private readonly Dictionary<string, string> _functionNameToOperatorDictionary = InitializeFunctionNameToOperatorDictionary();
    static private readonly Dictionary<string, object> _datepartKeywords = InitializeDatepartKeywords();
    static private readonly char[] hexDigits = { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'A', 'B', 'C', 'D', 'E', 'F' };

    private delegate ISqlFragment FunctionHandler(SqlGenerator sqlgen, DbFunctionExpression functionExpr);

    /// <summary>
    /// All special built-in functions and their handlers
    /// </summary>
    /// <returns></returns>
    private static Dictionary<string, FunctionHandler> InitializeBuiltInFunctionHandlers()
    {
      Dictionary<string, FunctionHandler> functionHandlers = new Dictionary<string, FunctionHandler>(5, StringComparer.Ordinal);
      functionHandlers.Add("concat", HandleConcatFunction);
      functionHandlers.Add("dateadd", HandleDatepartDateFunction);
      functionHandlers.Add("datediff", HandleDatepartDateFunction);
      functionHandlers.Add("datename", HandleDatepartDateFunction);
      functionHandlers.Add("datepart", HandleDatepartDateFunction);
      return functionHandlers;
    }

    /// <summary>
    /// All special non-aggregate canonical functions and their handlers
    /// </summary>
    /// <returns></returns>
    private static Dictionary<string, FunctionHandler> InitializeCanonicalFunctionHandlers()
    {
      Dictionary<string, FunctionHandler> functionHandlers = new Dictionary<string, FunctionHandler>(16, StringComparer.Ordinal);
      functionHandlers.Add("IndexOf", HandleCanonicalFunctionIndexOf);
      functionHandlers.Add("Length", HandleCanonicalFunctionLength);
      functionHandlers.Add("NewGuid", HandleCanonicalFunctionNewGuid);
      functionHandlers.Add("Round", HandleCanonicalFunctionRound);
      functionHandlers.Add("ToLower", HandleCanonicalFunctionToLower);
      functionHandlers.Add("ToUpper", HandleCanonicalFunctionToUpper);
      functionHandlers.Add("Trim", HandleCanonicalFunctionTrim);

      //DatePartFunctions
      functionHandlers.Add("Year", HandleCanonicalFunctionDatepart);
      functionHandlers.Add("Month", HandleCanonicalFunctionDatepart);
      functionHandlers.Add("Day", HandleCanonicalFunctionDatepart);
      functionHandlers.Add("Hour", HandleCanonicalFunctionDatepart);
      functionHandlers.Add("Minute", HandleCanonicalFunctionDatepart);
      functionHandlers.Add("Second", HandleCanonicalFunctionDatepart);
      functionHandlers.Add("DateAdd", HandleCanonicalFunctionDateAdd);
      functionHandlers.Add("DateDiff", HandleCanonicalFunctionDateSubtract);

      //Functions that translate to operators
      functionHandlers.Add("Concat", HandleConcatFunction);
      functionHandlers.Add("BitwiseAnd", HandleCanonicalFunctionBitwise);
      functionHandlers.Add("BitwiseNot", HandleCanonicalFunctionBitwise);
      functionHandlers.Add("BitwiseOr", HandleCanonicalFunctionBitwise);
      functionHandlers.Add("BitwiseXor", HandleCanonicalFunctionBitwise);
      return functionHandlers;
    }

    /// <summary>
    /// Valid datepart values
    /// </summary>
    /// <returns></returns>
    private static Dictionary<string, object> InitializeDatepartKeywords()
    {
      #region Datepart Keywords
      //
      // valid datepart values
      //
      Dictionary<string, object> datepartKeywords = new Dictionary<string, object>(30, StringComparer.Ordinal);
      datepartKeywords.Add("d", null);
      datepartKeywords.Add("day", null);
      datepartKeywords.Add("dayofyear", null);
      datepartKeywords.Add("dd", null);
      datepartKeywords.Add("dw", null);
      datepartKeywords.Add("dy", null);
      datepartKeywords.Add("hh", null);
      datepartKeywords.Add("hour", null);
      datepartKeywords.Add("m", null);
      datepartKeywords.Add("mi", null);
      datepartKeywords.Add("millisecond", null);
      datepartKeywords.Add("minute", null);
      datepartKeywords.Add("mm", null);
      datepartKeywords.Add("month", null);
      datepartKeywords.Add("ms", null);
      datepartKeywords.Add("n", null);
      datepartKeywords.Add("q", null);
      datepartKeywords.Add("qq", null);
      datepartKeywords.Add("quarter", null);
      datepartKeywords.Add("s", null);
      datepartKeywords.Add("second", null);
      datepartKeywords.Add("ss", null);
      datepartKeywords.Add("week", null);
      datepartKeywords.Add("weekday", null);
      datepartKeywords.Add("wk", null);
      datepartKeywords.Add("ww", null);
      datepartKeywords.Add("y", null);
      datepartKeywords.Add("year", null);
      datepartKeywords.Add("yy", null);
      datepartKeywords.Add("yyyy", null);
      return datepartKeywords;
      #endregion
    }

    /// <summary>
    /// Initializes the mapping from functions to T-SQL operators
    /// for all functions that translate to T-SQL operators
    /// </summary>
    /// <returns></returns>
    private static Dictionary<string, string> InitializeFunctionNameToOperatorDictionary()
    {
      Dictionary<string, string> functionNameToOperatorDictionary = new Dictionary<string, string>(5, StringComparer.Ordinal);
      functionNameToOperatorDictionary.Add("Concat", "+");    //canonical
      functionNameToOperatorDictionary.Add("CONCAT", "+");    //store
      functionNameToOperatorDictionary.Add("BitwiseAnd", "&");
      functionNameToOperatorDictionary.Add("BitwiseNot", "~");
      functionNameToOperatorDictionary.Add("BitwiseOr", "|");
      functionNameToOperatorDictionary.Add("BitwiseXor", "^");
      return functionNameToOperatorDictionary;
    }

    #endregion

    #region Constructor
    /// <summary>
    /// Basic constructor. 
    /// </summary>
    private SqlGenerator()
    {
    }
    #endregion

    #region Entry points
    /// <summary>
    /// General purpose static function that can be called from System.Data assembly
    /// </summary>
    /// <param name="sqlVersion">Server version</param>
    /// <param name="tree">command tree</param>
    /// <param name="parameters">Parameters to add to the command tree corresponding
    /// to constants in the command tree. Used only in ModificationCommandTrees.</param>
    /// <returns>The string representing the SQL to be executed.</returns>
    internal static string GenerateSql(DbCommandTree tree, out List<DbParameter> parameters, out CommandType commandType)
    {
      commandType = CommandType.Text;

      //Handle Query
      DbQueryCommandTree queryCommandTree = tree as DbQueryCommandTree;
      if (queryCommandTree != null)
      {
        SqlGenerator sqlGen = new SqlGenerator();
        parameters = null;
        
        string sql = sqlGen.GenerateSql((DbQueryCommandTree)tree);

        return sql;
      }

      //Handle Function
      DbFunctionCommandTree DbFunctionCommandTree = tree as DbFunctionCommandTree;
      if (DbFunctionCommandTree != null)
      {
        SqlGenerator sqlGen = new SqlGenerator();
        parameters = null;

        string sql = sqlGen.GenerateFunctionSql(DbFunctionCommandTree, out commandType);

        return sql;
      }

      //Handle Insert
      DbInsertCommandTree insertCommandTree = tree as DbInsertCommandTree;
      if (insertCommandTree != null)
      {
        return DmlSqlGenerator.GenerateInsertSql(insertCommandTree, out parameters);
      }

      //Handle Delete
      DbDeleteCommandTree deleteCommandTree = tree as DbDeleteCommandTree;
      if (deleteCommandTree != null)
      {
        return DmlSqlGenerator.GenerateDeleteSql(deleteCommandTree, out parameters);
      }

      //Handle Update
      DbUpdateCommandTree updateCommandTree = tree as DbUpdateCommandTree;
      if (updateCommandTree != null)
      {
        return DmlSqlGenerator.GenerateUpdateSql(updateCommandTree, out parameters);
      }

      throw new NotSupportedException("Unrecognized command tree type");
    }
    #endregion

    StringBuilder _typeDefs = new StringBuilder();

    #region Driver Methods
    /// <summary>
    /// Translate a command tree to a SQL string.
    ///
    /// The input tree could be translated to either a SQL SELECT statement
    /// or a SELECT expression.  This choice is made based on the return type
    /// of the expression
    /// CollectionType => select statement
    /// non collection type => select expression
    /// </summary>
    /// <param name="tree"></param>
    /// <returns>The string representing the SQL to be executed.</returns>
    private string GenerateSql(DbQueryCommandTree tree)
    {
      tree.Validate();

      selectStatementStack = new Stack<SqlSelectStatement>();
      isParentAJoinStack = new Stack<bool>();

      allExtentNames = new Dictionary<string, int>(StringComparer.OrdinalIgnoreCase);
      allColumnNames = new Dictionary<string, int>(StringComparer.OrdinalIgnoreCase);

      // Literals will not be converted to parameters.

      ISqlFragment result;
      if (MetadataHelpers.IsCollectionType(tree.Query.ResultType))
      {
        SqlSelectStatement sqlStatement = VisitExpressionEnsureSqlStatement(tree.Query);
        Debug.Assert(sqlStatement != null, "The outer most sql statment is null");
        sqlStatement.IsTopMost = true;
        result = sqlStatement;

      }
      else
      {
        SqlBuilder sqlBuilder = new SqlBuilder();
        sqlBuilder.Append("SELECT ");
        sqlBuilder.Append(tree.Query.Accept(this));

        result = sqlBuilder;
      }

      if (isVarRefSingle)
      {
        throw new NotSupportedException();
        // A DbVariableReferenceExpression has to be a child of DbPropertyExpression or MethodExpression
      }

      // Check that the parameter stacks are not leaking.
      Debug.Assert(selectStatementStack.Count == 0);
      Debug.Assert(isParentAJoinStack.Count == 0);

      if (_typeDefs.Length > 0)
      {
        _typeDefs.Insert(0x0, "TYPES ");
        _typeDefs.Append(";\r\n");
        _typeDefs.Append(WriteSql(result));
        return _typeDefs.ToString();
      }

      return WriteSql(result);
    }

    /// <summary>
    /// Translate a function command tree to a SQL string.
    /// </summary>
    private string GenerateFunctionSql(DbFunctionCommandTree tree, out CommandType commandType)
    {
      tree.Validate();

      EdmFunction function = tree.Function;

      // We expect function to always have these properties
      string userCommandText = (string)function.MetadataProperties["CommandTextAttribute"].Value;
      string userSchemaName = (string)function.MetadataProperties["Schema"].Value;
      string userFuncName = (string)function.MetadataProperties["StoreFunctionNameAttribute"].Value;

      if (String.IsNullOrEmpty(userCommandText))
      {
        // build a quoted description of the function
        commandType = CommandType.StoredProcedure;

        // if the schema name is not explicitly given, it is assumed to be the metadata namespace
        string schemaName = String.IsNullOrEmpty(userSchemaName) ?
            function.NamespaceName : userSchemaName;

        // if the function store name is not explicitly given, it is assumed to be the metadata name
        string functionName = String.IsNullOrEmpty(userFuncName) ?
            function.Name : userFuncName;

        // quote elements of function text
        string quotedSchemaName = QuoteIdentifier(schemaName);
        string quotedFunctionName = QuoteIdentifier(functionName);

        // separator
        const string schemaSeparator = ".";

        // concatenate elements of function text
        string quotedFunctionText = quotedSchemaName + schemaSeparator + quotedFunctionName;

        return quotedFunctionText;
      }
      else
      {
        // if the user has specified the command text, pass it through verbatim and choose CommandType.Text
        commandType = CommandType.Text;
        return userCommandText;
      }
    }

    /// <summary>
    /// Convert the SQL fragments to a string.
    /// We have to setup the Stream for writing.
    /// </summary>
    /// <param name="sqlStatement"></param>
    /// <returns>A string representing the SQL to be executed.</returns>
    string WriteSql(ISqlFragment sqlStatement)
    {
      StringBuilder builder = new StringBuilder(1024);
      using (SqlWriter writer = new SqlWriter(builder))
      {
        sqlStatement.WriteSql(writer, this);
      }

      return builder.ToString();
    }
    #endregion

    #region DbExpressionVisitor Members

    /// <summary>
    /// Translate(left) AND Translate(right)
    /// </summary>
    /// <param name="e"></param>
    /// <returns>A <see cref="SqlBuilder"/>.</returns>
    public override ISqlFragment Visit(DbAndExpression e)
    {
      return VisitBinaryExpression(" AND ", e.Left, e.Right);
    }

    /// <summary>
    /// An apply is just like a join, so it shares the common join processing
    /// in <see cref="VisitJoinExpression"/>
    /// </summary>
    /// <param name="e"></param>
    /// <returns>A <see cref="SqlSelectStatement"/>.</returns>
    public override ISqlFragment Visit(DbApplyExpression e)
    {
      List<DbExpressionBinding> inputs = new List<DbExpressionBinding>();
      inputs.Add(e.Input);
      inputs.Add(e.Apply);

      string joinString;
      switch (e.ExpressionKind)
      {
        case DbExpressionKind.CrossApply:
          joinString = "CROSS APPLY";
          break;

        case DbExpressionKind.OuterApply:
          joinString = "OUTER APPLY";
          break;

        default:
          Debug.Assert(false);
          throw new InvalidOperationException();
      }

      // The join condition does not exist in this case, so we use null.
      // We do not have a on clause, so we use JoinType.CrossJoin.
      return VisitJoinExpression(inputs, DbExpressionKind.CrossJoin, joinString, null);
    }

    /// <summary>
    /// For binary expressions, we delegate to <see cref="VisitBinaryExpression"/>.
    /// We handle the other expressions directly.
    /// </summary>
    /// <param name="e"></param>
    /// <returns>A <see cref="SqlBuilder"/></returns>
    public override ISqlFragment Visit(DbArithmeticExpression e)
    {
      SqlBuilder result;

      switch (e.ExpressionKind)
      {
        case DbExpressionKind.Divide:
          result = VisitBinaryExpression(" / ", e.Arguments[0], e.Arguments[1]);
          break;
        case DbExpressionKind.Minus:
          result = VisitBinaryExpression(" - ", e.Arguments[0], e.Arguments[1]);
          break;
        case DbExpressionKind.Modulo:
          result = VisitBinaryExpression(" % ", e.Arguments[0], e.Arguments[1]);
          break;
        case DbExpressionKind.Multiply:
          result = VisitBinaryExpression(" * ", e.Arguments[0], e.Arguments[1]);
          break;
        case DbExpressionKind.Plus:
          result = VisitBinaryExpression(" + ", e.Arguments[0], e.Arguments[1]);
          break;

        case DbExpressionKind.UnaryMinus:
          result = new SqlBuilder();
          result.Append(" -(");
          result.Append(e.Arguments[0].Accept(this));
          result.Append(")");
          break;

        default:
          Debug.Assert(false);
          throw new InvalidOperationException();
      }

      return result;
    }

    /// <summary>
    /// If the ELSE clause is null, we do not write it out.
    /// </summary>
    /// <param name="e"></param>
    /// <returns>A <see cref="SqlBuilder"/></returns>
    public override ISqlFragment Visit(DbCaseExpression e)
    {
      SqlBuilder result = new SqlBuilder();

      Debug.Assert(e.When.Count == e.Then.Count);

      result.Append("CASE");
      for (int i = 0; i < e.When.Count; ++i)
      {
        result.Append(" WHEN (");
        result.Append(e.When[i].Accept(this));
        result.Append(") THEN ");
        result.Append(e.Then[i].Accept(this));
      }
      if (e.Else != null && !(e.Else is DbNullExpression))
      {
        result.Append(" ELSE ");
        result.Append(e.Else.Accept(this));
      }

      result.Append(" END");

      return result;
    }

    /// <summary>
    ///
    /// </summary>
    /// <param name="e"></param>
    /// <returns></returns>
    public override ISqlFragment Visit(DbCastExpression e)
    {
      SqlBuilder result = new SqlBuilder();
      result.Append(e.Argument.Accept(this));
      return result;
    }

    /// <summary>
    /// The parser generates Not(Equals(...)) for &lt;&gt;.
    /// </summary>
    /// <param name="e"></param>
    /// <returns>A <see cref="SqlBuilder"/>.</returns>
    public override ISqlFragment Visit(DbComparisonExpression e)
    {
      SqlBuilder result;
      switch (e.ExpressionKind)
      {
        case DbExpressionKind.Equals:
          //if (e.Left.ResultType.EdmType.Name == "String" && e.Right.ResultType.EdmType.Name == "String")
          //  result = VisitBinaryExpression(" LIKE ", e.Left, e.Right);
          //else
            result = VisitBinaryExpression(" = ", e.Left, e.Right);
          break;
        case DbExpressionKind.LessThan:
          result = VisitBinaryExpression(" < ", e.Left, e.Right);
          break;
        case DbExpressionKind.LessThanOrEquals:
          result = VisitBinaryExpression(" <= ", e.Left, e.Right);
          break;
        case DbExpressionKind.GreaterThan:
          result = VisitBinaryExpression(" > ", e.Left, e.Right);
          break;
        case DbExpressionKind.GreaterThanOrEquals:
          result = VisitBinaryExpression(" >= ", e.Left, e.Right);
          break;
        // The parser does not generate the expression kind below.
        case DbExpressionKind.NotEquals:
          result = VisitBinaryExpression(" <> ", e.Left, e.Right);
          break;

        default:
          Debug.Assert(false);  // The constructor should have prevented this
          throw new InvalidOperationException(String.Empty);
      }

      return result;
    }

    /// <summary>

    /// Constants will be send to the store as part of the generated TSQL, not as parameters
    /// </summary>
    /// <param name="e"></param>
    /// <returns>A <see cref="SqlBuilder"/>.  Strings are wrapped in single
    /// quotes and escaped.  Numbers are written literally.</returns>
    public override ISqlFragment Visit(DbConstantExpression e)
    {
      SqlBuilder result = new SqlBuilder();

      PrimitiveTypeKind typeKind;
      // Model Types can be (at the time of this implementation):
      //      Binary, Boolean, Byte, DateTime, Decimal, Double, Guid, Int16, Int32, Int64,Single, String
      if (MetadataHelpers.TryGetPrimitiveTypeKind(e.ResultType, out typeKind))
      {
        switch (typeKind)
        {
          case PrimitiveTypeKind.Int32:
            // default sql server type for integral values.
            result.Append(e.Value.ToString());
            break;

          case PrimitiveTypeKind.Binary:
            result.Append(" 0x");
            result.Append(ByteArrayToBinaryString((Byte[])e.Value));
            result.Append(" ");
            break;

          case PrimitiveTypeKind.Boolean:
            result.Append((bool)e.Value ? "1" : "0");
            break;

          case PrimitiveTypeKind.Byte:
            result.Append(e.Value.ToString());
            break;

          case PrimitiveTypeKind.DateTime:
            result.Append(EscapeSingleQuote(((System.DateTime)e.Value).ToString("yyyy-MM-dd HH:mm:ss.fff", CultureInfo.InvariantCulture), false /* IsUnicode */));
            break;

          case PrimitiveTypeKind.Decimal:
            string strDecimal = ((Decimal)e.Value).ToString(CultureInfo.InvariantCulture);
            // if the decimal value has no decimal part, cast as decimal to preserve type
            // if the number has precision > int64 max precision, it will be handled as decimal by sql server
            // and does not need cast. if precision is lest then 20, then cast using Max(literal precision, sql default precision)
            if (-1 == strDecimal.IndexOf('.') && (strDecimal.TrimStart(new char[] { '-' }).Length < 20))
            {
              byte precision = (Byte)strDecimal.Length;
              FacetDescription precisionFacetDescription;
              Debug.Assert(MetadataHelpers.TryGetTypeFacetDescriptionByName(e.ResultType.EdmType, "precision", out precisionFacetDescription), "Decimal primitive type must have Precision facet");
              if (MetadataHelpers.TryGetTypeFacetDescriptionByName(e.ResultType.EdmType, "precision", out precisionFacetDescription))
              {
                if (precisionFacetDescription.DefaultValue != null)
                {
                  precision = Math.Max(precision, (byte)precisionFacetDescription.DefaultValue);
                }
              }
              Debug.Assert(precision > 0, "Precision must be greater than zero");
              result.Append(strDecimal);
            }
            else
            {
              result.Append(strDecimal);
            }
            break;

          case PrimitiveTypeKind.Double:
            result.Append(((Double)e.Value).ToString(CultureInfo.InvariantCulture));
            break;

          case PrimitiveTypeKind.Guid:
            result.Append(EscapeSingleQuote(e.Value.ToString(), false /* IsUnicode */));
            break;

          case PrimitiveTypeKind.Int16:
            result.Append(e.Value.ToString());
            break;

          case PrimitiveTypeKind.Int64:
            result.Append(e.Value.ToString());
            break;

          case PrimitiveTypeKind.Single:
            result.Append(((Single)e.Value).ToString(CultureInfo.InvariantCulture));
            break;

          case PrimitiveTypeKind.String:
            bool isUnicode = MetadataHelpers.GetFacetValueOrDefault<bool>(e.ResultType, MetadataHelpers.UnicodeFacetName, true);
            result.Append(EscapeSingleQuote(e.Value as string, isUnicode));
            break;

          default:
            // all known scalar types should been handled already.
            throw new NotSupportedException();
        }
      }
      else
      {
        throw new NotSupportedException();
      }

      return result;

    }

    /// <summary>
    /// <see cref="DbDerefExpression"/> is illegal at this stage
    /// </summary>
    /// <param name="e"></param>
    /// <returns></returns>
    public override ISqlFragment Visit(DbDerefExpression e)
    {
      throw new NotSupportedException();
    }

    /// <summary>
    /// The DISTINCT has to be added to the beginning of SqlSelectStatement.Select,
    /// but it might be too late for that.  So, we use a flag on SqlSelectStatement
    /// instead, and add the "DISTINCT" in the second phase.
    /// </summary>
    /// <param name="e"></param>
    /// <returns>A <see cref="SqlSelectStatement"/></returns>
    public override ISqlFragment Visit(DbDistinctExpression e)
    {
      SqlSelectStatement result = VisitExpressionEnsureSqlStatement(e.Argument);

      if (!IsCompatible(result, e.ExpressionKind))
      {
        Symbol fromSymbol;
        TypeUsage inputType = MetadataHelpers.GetElementTypeUsage(e.Argument.ResultType);
        result = CreateNewSelectStatement(result, "distinct", inputType, out fromSymbol);
        AddFromSymbol(result, "distinct", fromSymbol, false);
      }

      result.IsDistinct = true;
      return result;
    }

    /// <summary>
    /// An element expression returns a scalar - so it is translated to
    /// ( Select ... )
    /// </summary>
    /// <param name="e"></param>
    /// <returns></returns>
    public override ISqlFragment Visit(DbElementExpression e)
    {
      SqlBuilder result = new SqlBuilder();
      result.Append("(");
      result.Append(VisitExpressionEnsureSqlStatement(e.Argument));
      result.Append(")");

      return result;
    }

    /// <summary>
    /// <see cref="Visit(DbUnionAllExpression)"/>
    /// </summary>
    /// <param name="e"></param>
    /// <returns></returns>
    public override ISqlFragment Visit(DbExceptExpression e)
    {
      return VisitSetOpExpression(e.Left, e.Right, "EXCEPT");
    }

    /// <summary>
    /// Only concrete expression types will be visited.
    /// </summary>
    /// <param name="e"></param>
    /// <returns></returns>
    public override ISqlFragment Visit(DbExpression e)
    {
      throw new InvalidOperationException();
    }

    /// <summary>
    ///
    /// </summary>
    /// <param name="e"></param>
    /// <returns>If we are in a Join context, returns a <see cref="SqlBuilder"/>
    /// with the extent name, otherwise, a new <see cref="SqlSelectStatement"/>
    /// with the From field set.</returns>
    public override ISqlFragment Visit(DbScanExpression e)
    {
      EntitySetBase target = e.Target;

      if (IsParentAJoin)
      {
        SqlBuilder result = new SqlBuilder();
        result.Append(GetTargetTSql(target));

        return result;
      }
      else
      {
        SqlSelectStatement result = new SqlSelectStatement();
        result.From.Append(GetTargetTSql(target));

        return result;
      }
    }


    /// <summary>
    /// Gets escaped TSql identifier describing this entity set.
    /// </summary>
    /// <returns></returns>
    internal static string GetTargetTSql(EntitySetBase entitySetBase)
    {
      // construct escaped T-SQL referencing entity set
      StringBuilder builder = new StringBuilder(50);
      string definingQuery = MetadataHelpers.TryGetValueForMetadataProperty<string>(entitySetBase, "DefiningQuery");
      if (!string.IsNullOrEmpty(definingQuery))
      {
        builder.Append("(");
        builder.Append(definingQuery);
        builder.Append(")");
      }
      else
      {
        string schemaName = MetadataHelpers.TryGetValueForMetadataProperty<string>(entitySetBase, "Schema");
        if (!string.IsNullOrEmpty(schemaName))
        {
          builder.Append(SqlGenerator.QuoteIdentifier(schemaName));
          builder.Append(".");
        }
        //else
        //{
        //  builder.Append(SqlGenerator.QuoteIdentifier(entitySetBase.EntityContainer.Name));
        //  builder.Append(".");
        //}

        string tableName = MetadataHelpers.TryGetValueForMetadataProperty<string>(entitySetBase, "Table");
        if (!string.IsNullOrEmpty(tableName))
        {
          builder.Append(SqlGenerator.QuoteIdentifier(tableName));
        }
        else
        {
          builder.Append(SqlGenerator.QuoteIdentifier(entitySetBase.Name));
        }
      }
      return builder.ToString();
    }

    /// <summary>
    /// The bodies of <see cref="Visit(DbFilterExpression)"/>, <see cref="Visit(DbGroupByExpression)"/>,
    /// <see cref="Visit(DbProjectExpression)"/>, <see cref="Visit(DbSortExpression)"/> are similar.
    /// Each does the following.
    /// <list type="number">
    /// <item> Visit the input expression</item>
    /// <item> Determine if the input's SQL statement can be reused, or a new
    /// one must be created.</item>
    /// <item>Create a new symbol table scope</item>
    /// <item>Push the Sql statement onto a stack, so that children can
    /// update the free variable list.</item>
    /// <item>Visit the non-input expression.</item>
    /// <item>Cleanup</item>
    /// </list>
    /// </summary>
    /// <param name="e"></param>
    /// <returns>A <see cref="SqlSelectStatement"/></returns>
    public override ISqlFragment Visit(DbFilterExpression e)
    {
      return VisitFilterExpression(e.Input, e.Predicate, false);
    }

    /// <summary>
    /// Lambda functions are not supported.
    /// The functions supported are:
    /// <list type="number">
    /// <item>Canonical Functions - We recognize these by their dataspace, it is DataSpace.CSpace</item>
    /// <item>Store Functions - We recognize these by the BuiltInAttribute and not being Canonical</item>
    /// <item>User-defined Functions - All the rest except for Lambda functions</item>
    /// </list>
    /// We handle Canonical and Store functions the same way: If they are in the list of functions 
    /// that need special handling, we invoke the appropriate handler, otherwise we translate them to
    /// FunctionName(arg1, arg2, ..., argn).
    /// We translate user-defined functions to NamespaceName.FunctionName(arg1, arg2, ..., argn).
    /// </summary>
    /// <param name="e"></param>
    /// <returns>A <see cref="SqlBuilder"/></returns>
    public override ISqlFragment Visit(DbFunctionExpression e)
    {
      if (e.IsLambda)
      {
        throw new NotSupportedException();
      }

      //
      // check if function requires special case processing, if so, delegates to it
      //
      if (IsSpecialBuiltInFunction(e))
      {
        return HandleSpecialBuiltInFunction(e);
      }

      if (IsSpecialCanonicalFunction(e))
      {
        return HandleSpecialCanonicalFunction(e);
      }

      return HandleFunctionDefault(e);
    }


    /// <summary>
    /// <see cref="DbEntityRefExpression"/> is illegal at this stage
    /// </summary>
    /// <param name="e"></param>
    /// <returns></returns>
    public override ISqlFragment Visit(DbEntityRefExpression e)
    {
      throw new NotSupportedException();
    }

    /// <summary>
    /// <see cref="DbRefKeyExpression"/> is illegal at this stage
    /// </summary>
    /// <param name="e"></param>
    /// <returns></returns>
    public override ISqlFragment Visit(DbRefKeyExpression e)
    {
      throw new NotSupportedException();
    }

    /// <summary>
    /// <see cref="Visit(DbFilterExpression)"/> for general details.
    /// We modify both the GroupBy and the Select fields of the SqlSelectStatement.
    /// GroupBy gets just the keys without aliases,
    /// and Select gets the keys and the aggregates with aliases.
    /// 
    /// Whenever there exists at least one aggregate with an argument that is not is not a simple
    /// <see cref="DbPropertyExpression"/>  over <see cref="DbVariableReferenceExpression"/>, 
    /// we create a nested query in which we alias the arguments to the aggregates. 
    /// That is due to the following two limitations of Sql Server:
    /// <list type="number">
    /// <item>If an expression being aggregated contains an outer reference, then that outer 
    /// reference must be the only column referenced in the expression </item>
    /// <item>Sql Server cannot perform an aggregate function on an expression containing 
    /// an aggregate or a subquery. </item>
    /// </list>
    /// 
    /// The default translation, without inner query is: 
    /// 
    ///     SELECT 
    ///         kexp1 AS key1, kexp2 AS key2,... kexpn AS keyn, 
    ///         aggf1(aexpr1) AS agg1, .. aggfn(aexprn) AS aggn
    ///     FROM input AS a
    ///     GROUP BY kexp1, kexp2, .. kexpn
    /// 
    /// When we inject an innner query, the equivalent translation is:
    /// 
    ///     SELECT 
    ///         key1 AS key1, key2 AS key2, .. keyn AS keys,  
    ///         aggf1(agg1) AS agg1, aggfn(aggn) AS aggn
    ///     FROM (
    ///             SELECT 
    ///                 kexp1 AS key1, kexp2 AS key2,... kexpn AS keyn, 
    ///                 aexpr1 AS agg1, .. aexprn AS aggn
    ///             FROM input AS a
    ///         ) as a
    ///     GROUP BY key1, key2, keyn
    /// 
    /// </summary>
    /// <param name="e"></param>
    /// <returns>A <see cref="SqlSelectStatement"/></returns>
    public override ISqlFragment Visit(DbGroupByExpression e)
    {
      Symbol fromSymbol;
      //SqlSelectStatement result = VisitInputExpression(e.Input.Expression,
      SqlSelectStatement innerQuery = VisitInputExpression(e.Input.Expression,
          e.Input.VariableName, e.Input.VariableType, out fromSymbol);

      // GroupBy is compatible with Filter and OrderBy
      // but not with Project, GroupBy
      if (!IsCompatible(innerQuery, e.ExpressionKind))
      {
        innerQuery = CreateNewSelectStatement(innerQuery, e.Input.VariableName, e.Input.VariableType, out fromSymbol);
      }

      selectStatementStack.Push(innerQuery);
      symbolTable.EnterScope();

      AddFromSymbol(innerQuery, e.Input.VariableName, fromSymbol);
      // This line is not present for other relational nodes.
      symbolTable.Add(e.Input.GroupVariableName, fromSymbol);


      // The enumerator is shared by both the keys and the aggregates,
      // so, we do not close it in between.
      RowType groupByType = MetadataHelpers.GetEdmType<RowType>(MetadataHelpers.GetEdmType<CollectionType>(e.ResultType).TypeUsage);

      //Whenever there exists at least one aggregate with an argument that is not simply a PropertyExpression 
      // over a VarRefExpression, we need a nested query in which we alias the arguments to the aggregates.
      bool needsInnerQuery = NeedsInnerQuery(e.Aggregates);

      SqlSelectStatement result;
      if (needsInnerQuery)
      {
        //Create the inner query
        result = CreateNewSelectStatement(innerQuery, e.Input.VariableName, e.Input.VariableType, false, out fromSymbol);
        AddFromSymbol(result, e.Input.VariableName, fromSymbol, false);
      }
      else
      {
        result = innerQuery;
      }

      using (IEnumerator<EdmProperty> members = groupByType.Properties.GetEnumerator())
      {
        members.MoveNext();
        Debug.Assert(result.Select.IsEmpty);

        string separator = "";

        foreach (DbExpression key in e.Keys)
        {
          EdmProperty member = members.Current;
          string alias = QuoteIdentifier(member.Name);

          result.GroupBy.Append(separator);

          ISqlFragment keySql = key.Accept(this);

          if (!needsInnerQuery)
          {
            //Default translation: Key AS Alias
            result.Select.Append(separator);
            result.Select.AppendLine();
            result.Select.Append(keySql);
            result.Select.Append(" AS ");
            result.Select.Append(alias);

            result.GroupBy.Append(keySql);
          }
          else
          {
            // The inner query contains the default translation Key AS Alias
            innerQuery.Select.Append(separator);
            innerQuery.Select.AppendLine();
            innerQuery.Select.Append(keySql);
            innerQuery.Select.Append(" AS ");
            innerQuery.Select.Append(alias);

            //The outer resulting query projects over the key aliased in the inner query: 
            //  fromSymbol.Alias AS Alias
            result.Select.Append(separator);
            result.Select.AppendLine();
            result.Select.Append(fromSymbol);
            result.Select.Append(".");
            result.Select.Append(alias);
            result.Select.Append(" AS ");
            result.Select.Append(alias);

            result.GroupBy.Append(alias);
          }

          separator = ", ";
          members.MoveNext();
        }

        foreach (DbAggregate aggregate in e.Aggregates)
        {
          EdmProperty member = members.Current;
          string alias = QuoteIdentifier(member.Name);

          Debug.Assert(aggregate.Arguments.Count == 1);
          ISqlFragment translatedAggregateArgument = aggregate.Arguments[0].Accept(this);

          object aggregateArgument;

          if (needsInnerQuery)
          {
            //In this case the argument to the aggratete is reference to the one projected out by the
            // inner query
            SqlBuilder wrappingAggregateArgument = new SqlBuilder();
            wrappingAggregateArgument.Append(fromSymbol);
            wrappingAggregateArgument.Append(".");
            wrappingAggregateArgument.Append(alias);
            aggregateArgument = wrappingAggregateArgument;

            innerQuery.Select.Append(separator);
            innerQuery.Select.AppendLine();
            innerQuery.Select.Append(translatedAggregateArgument);
            innerQuery.Select.Append(" AS ");
            innerQuery.Select.Append(alias);
          }
          else
          {
            aggregateArgument = translatedAggregateArgument;
          }

          ISqlFragment aggregateResult = VisitAggregate(aggregate, aggregateArgument);

          result.Select.Append(separator);
          result.Select.AppendLine();
          result.Select.Append(aggregateResult);
          result.Select.Append(" AS ");
          result.Select.Append(alias);

          separator = ", ";
          members.MoveNext();
        }
      }


      symbolTable.ExitScope();
      selectStatementStack.Pop();

      return result;
    }

    /// <summary>
    /// <see cref="Visit(DbUnionAllExpression)"/>
    /// </summary>
    /// <param name="e"></param>
    /// <returns></returns>
    public override ISqlFragment Visit(DbIntersectExpression e)
    {
      return VisitSetOpExpression(e.Left, e.Right, "INTERSECT");
    }

    /// <summary>
    /// Not(IsEmpty) has to be handled specially, so we delegate to
    /// <see cref="VisitIsEmptyExpression"/>.
    ///
    /// </summary>
    /// <param name="e"></param>
    /// <returns>A <see cref="SqlBuilder"/>.
    /// <code>[NOT] EXISTS( ... )</code>
    /// </returns>
    public override ISqlFragment Visit(DbIsEmptyExpression e)
    {
      return VisitIsEmptyExpression(e, false);
    }

    /// <summary>
    /// Not(IsNull) is handled specially, so we delegate to
    /// <see cref="VisitIsNullExpression"/>
    /// </summary>
    /// <param name="e"></param>
    /// <returns>A <see cref="SqlBuilder"/>
    /// <code>IS [NOT] NULL</code>
    /// </returns>
    public override ISqlFragment Visit(DbIsNullExpression e)
    {
      return VisitIsNullExpression(e, false);
    }

    /// <summary>
    /// <see cref="DbIsOfExpression"/> is illegal at this stage
    /// </summary>
    /// <param name="e"></param>
    /// <returns>A <see cref="SqlBuilder"/></returns>
    public override ISqlFragment Visit(DbIsOfExpression e)
    {
      throw new NotSupportedException();
    }

    /// <summary>
    /// <see cref="VisitJoinExpression"/>
    /// </summary>
    /// <param name="e"></param>
    /// <returns>A <see cref="SqlSelectStatement"/>.</returns>
    public override ISqlFragment Visit(DbCrossJoinExpression e)
    {
      return VisitJoinExpression(e.Inputs, e.ExpressionKind, "CROSS JOIN", null);
    }

    /// <summary>
    /// <see cref="VisitJoinExpression"/>
    /// </summary>
    /// <param name="e"></param>
    /// <returns>A <see cref="SqlSelectStatement"/>.</returns>
    public override ISqlFragment Visit(DbJoinExpression e)
    {
      #region Map join type to a string
      string joinString;
      switch (e.ExpressionKind)
      {
        case DbExpressionKind.FullOuterJoin:
          joinString = "FULL OUTER JOIN";
          break;

        case DbExpressionKind.InnerJoin:
          joinString = "INNER JOIN";
          break;

        case DbExpressionKind.LeftOuterJoin:
          joinString = "LEFT OUTER JOIN";
          break;

        default:
          Debug.Assert(false);
          joinString = null;
          break;
      }
      #endregion

      List<DbExpressionBinding> inputs = new List<DbExpressionBinding>(2);
      inputs.Add(e.Left);
      inputs.Add(e.Right);

      return VisitJoinExpression(inputs, e.ExpressionKind, joinString, e.JoinCondition);
    }

    /// <summary>
    ///
    /// </summary>
    /// <param name="e"></param>
    /// <returns>A <see cref="SqlBuilder"/></returns>
    public override ISqlFragment Visit(DbLikeExpression e)
    {
      SqlBuilder result = new SqlBuilder();
      result.Append(e.Argument.Accept(this));
      result.Append(" LIKE ");
      result.Append(e.Pattern.Accept(this));

      // if the ESCAPE expression is a DbNullExpression, then that's tantamount to 
      // not having an ESCAPE at all
      if (e.Escape.ExpressionKind != DbExpressionKind.Null)
      {
        result.Append(" ESCAPE ");
        result.Append(e.Escape.Accept(this));
      }

      return result;
    }

    /// <summary>
    ///  Translates to TOP expression.
    /// </summary>
    /// <param name="e"></param>
    /// <returns>A <see cref="SqlBuilder"/></returns>
    public override ISqlFragment Visit(DbLimitExpression e)
    {
      Debug.Assert(e.Limit is DbConstantExpression || e.Limit is DbParameterReferenceExpression, "DbLimitExpression.Limit is of invalid expression type");

      SqlSelectStatement result = VisitExpressionEnsureSqlStatement(e.Argument, false);
      Symbol fromSymbol;

      if (!IsCompatible(result, e.ExpressionKind))
      {
        TypeUsage inputType = MetadataHelpers.GetElementTypeUsage(e.Argument.ResultType);

        result = CreateNewSelectStatement(result, "top", inputType, out fromSymbol);
        AddFromSymbol(result, "top", fromSymbol, false);
      }

      ISqlFragment topCount = HandaleCountExpression(e.Limit);

      result.Top = new TopClause(topCount, e.WithTies);
      return result;
    }

    /// <summary>
    /// DbNewInstanceExpression is allowed as a child of DbProjectExpression only.
    /// If anyone else is the parent, we throw.
    /// We also perform special casing for collections - where we could convert
    /// them into Unions
    ///
    /// <see cref="VisitNewInstanceExpression"/> for the actual implementation.
    ///
    /// </summary>
    /// <param name="e"></param>
    /// <returns></returns>
    public override ISqlFragment Visit(DbNewInstanceExpression e)
    {
      if (MetadataHelpers.IsCollectionType(e.ResultType))
      {
        return VisitCollectionConstructor(e);
      }
      throw new NotSupportedException();
    }

    /// <summary>
    /// The Not expression may cause the translation of its child to change.
    /// These children are
    /// <list type="bullet">
    /// <item><see cref="DbNotExpression"/>NOT(Not(x)) becomes x</item>
    /// <item><see cref="DbIsEmptyExpression"/>NOT EXISTS becomes EXISTS</item>
    /// <item><see cref="DbIsNullExpression"/>IS NULL becomes IS NOT NULL</item>
    /// <item><see cref="DbComparisonExpression"/>= becomes&lt;&gt; </item>
    /// </list>
    /// </summary>
    /// <param name="e"></param>
    /// <returns>A <see cref="SqlBuilder"/></returns>
    public override ISqlFragment Visit(DbNotExpression e)
    {
      // Flatten Not(Not(x)) to x.
      DbNotExpression notExpression = e.Argument as DbNotExpression;
      if (notExpression != null)
      {
        return notExpression.Argument.Accept(this);
      }

      DbIsEmptyExpression isEmptyExpression = e.Argument as DbIsEmptyExpression;
      if (isEmptyExpression != null)
      {
        return VisitIsEmptyExpression(isEmptyExpression, true);
      }

      DbIsNullExpression isNullExpression = e.Argument as DbIsNullExpression;
      if (isNullExpression != null)
      {
        return VisitIsNullExpression(isNullExpression, true);
      }

      DbComparisonExpression comparisonExpression = e.Argument as DbComparisonExpression;
      if (comparisonExpression != null)
      {
        if (comparisonExpression.ExpressionKind == DbExpressionKind.Equals)
        {
          return VisitBinaryExpression(" <> ", comparisonExpression.Left, comparisonExpression.Right);
        }
      }

      SqlBuilder result = new SqlBuilder();
      result.Append(" NOT (");
      result.Append(e.Argument.Accept(this));
      result.Append(")");

      return result;
    }

    /// <summary>
    /// </summary>
    /// <param name="e"></param>
    /// <returns><see cref="SqlBuilder"/></returns>
    public override ISqlFragment Visit(DbNullExpression e)
    {
      SqlBuilder result = new SqlBuilder();
      // always cast nulls - sqlserver doesn't like case expressions where the "then" clause is null
      result.Append("NULL");
      return result;
    }

    /// <summary>
    /// <see cref="DbOfTypeExpression"/> is illegal at this stage
    /// </summary>
    /// <param name="e"></param>
    /// <returns>A <see cref="SqlBuilder"/></returns>
    public override ISqlFragment Visit(DbOfTypeExpression e)
    {
      throw new NotSupportedException();
    }

    /// <summary>
    ///
    /// </summary>
    /// <param name="e"></param>
    /// <returns>A <see cref="SqlBuilder"/></returns>
    /// <seealso cref="Visit(DbAndExpression)"/>
    public override ISqlFragment Visit(DbOrExpression e)
    {
      return VisitBinaryExpression(" OR ", e.Left, e.Right);
    }

    /// <summary>
    ///
    /// </summary>
    /// <param name="e"></param>
    /// <returns>A <see cref="SqlBuilder"/></returns>
    public override ISqlFragment Visit(DbParameterReferenceExpression e)
    {
      SqlBuilder result = new SqlBuilder();
      // Do not quote this name.
      // We are not checking that e.Name has no illegal characters. e.g. space
      result.Append("@" + e.ParameterName);

      return result;
    }

    /// <summary>
    /// <see cref="Visit(DbFilterExpression)"/> for the general ideas.
    /// </summary>
    /// <param name="e"></param>
    /// <returns>A <see cref="SqlSelectStatement"/></returns>
    /// <seealso cref="Visit(DbFilterExpression)"/>
    public override ISqlFragment Visit(DbProjectExpression e)
    {
      Symbol fromSymbol;
      SqlSelectStatement result = VisitInputExpression(e.Input.Expression, e.Input.VariableName, e.Input.VariableType, out fromSymbol);

      // Project is compatible with Filter
      // but not with Project, GroupBy
      if (!IsCompatible(result, e.ExpressionKind))
      {
        result = CreateNewSelectStatement(result, e.Input.VariableName, e.Input.VariableType, out fromSymbol);
      }

      selectStatementStack.Push(result);
      symbolTable.EnterScope();

      AddFromSymbol(result, e.Input.VariableName, fromSymbol);

      // Project is the only node that can have DbNewInstanceExpression as a child
      // so we have to check it here.
      // We call VisitNewInstanceExpression instead of Visit(DbNewInstanceExpression), since
      // the latter throws.
      DbNewInstanceExpression newInstanceExpression = e.Projection as DbNewInstanceExpression;
      if (newInstanceExpression != null)
      {
        result.Select.Append(VisitNewInstanceExpression(newInstanceExpression));
      }
      else
      {
        result.Select.Append(e.Projection.Accept(this));
      }

      symbolTable.ExitScope();
      selectStatementStack.Pop();

      return result;
    }

    /// <summary>
    /// This method handles record flattening, which works as follows.
    /// consider an expression <c>Prop(y, Prop(x, Prop(d, Prop(c, Prop(b, Var(a)))))</c>
    /// where a,b,c are joins, d is an extent and x and y are fields.
    /// b has been flattened into a, and has its own SELECT statement.
    /// c has been flattened into b.
    /// d has been flattened into c.
    ///
    /// We visit the instance, so we reach Var(a) first.  This gives us a (join)symbol.
    /// Symbol(a).b gives us a join symbol, with a SELECT statement i.e. Symbol(b).
    /// From this point on , we need to remember Symbol(b) as the source alias,
    /// and then try to find the column.  So, we use a SymbolPair.
    ///
    /// We have reached the end when the symbol no longer points to a join symbol.
    /// </summary>
    /// <param name="e"></param>
    /// <returns>A <see cref="JoinSymbol"/> if we have not reached the first
    /// Join node that has a SELECT statement.
    /// A <see cref="SymbolPair"/> if we have seen the JoinNode, and it has
    /// a SELECT statement.
    /// A <see cref="SqlBuilder"/> with {Input}.propertyName otherwise.
    /// </returns>
    public override ISqlFragment Visit(DbPropertyExpression e)
    {
      SqlBuilder result;

      ISqlFragment instanceSql = e.Instance.Accept(this);

      // Since the DbVariableReferenceExpression is a proper child of ours, we can reset
      // isVarSingle.
      DbVariableReferenceExpression DbVariableReferenceExpression = e.Instance as DbVariableReferenceExpression;
      if (DbVariableReferenceExpression != null)
      {
        isVarRefSingle = false;
      }

      // We need to flatten, and have not yet seen the first nested SELECT statement.
      JoinSymbol joinSymbol = instanceSql as JoinSymbol;
      if (joinSymbol != null)
      {
        Debug.Assert(joinSymbol.NameToExtent.ContainsKey(e.Property.Name));
        if (joinSymbol.IsNestedJoin)
        {
          return new SymbolPair(joinSymbol, joinSymbol.NameToExtent[e.Property.Name]);
        }
        else
        {
          return joinSymbol.NameToExtent[e.Property.Name];
        }
      }

      // ---------------------------------------
      // We have seen the first nested SELECT statement, but not the column.
      SymbolPair symbolPair = instanceSql as SymbolPair;
      if (symbolPair != null)
      {
        JoinSymbol columnJoinSymbol = symbolPair.Column as JoinSymbol;
        if (columnJoinSymbol != null)
        {
          symbolPair.Column = columnJoinSymbol.NameToExtent[e.Property.Name];
          return symbolPair;
        }
        else
        {
          // symbolPair.Column has the base extent.
          // we need the symbol for the column, since it might have been renamed
          // when handling a JOIN.
          if (symbolPair.Column.Columns.ContainsKey(e.Property.Name))
          {
            result = new SqlBuilder();
            result.Append(symbolPair.Source);
            result.Append(".");
            result.Append(symbolPair.Column.Columns[e.Property.Name]);
            return result;
          }
        }
      }
      // ---------------------------------------

      result = new SqlBuilder();
      result.Append(instanceSql);
      result.Append(".");

      // At this point the column name cannot be renamed, so we do
      // not use a symbol.
      result.Append(QuoteIdentifier(e.Property.Name));

      return result;
    }

    /// <summary>
    /// Any(input, x) => Exists(Filter(input,x))
    /// All(input, x) => Not Exists(Filter(input, not(x))
    /// </summary>
    /// <param name="e"></param>
    /// <returns></returns>
    public override ISqlFragment Visit(DbQuantifierExpression e)
    {
      SqlBuilder result = new SqlBuilder();

      bool negatePredicate = (e.ExpressionKind == DbExpressionKind.All);
      if (e.ExpressionKind == DbExpressionKind.Any)
      {
        result.Append("EXISTS (");
      }
      else
      {
        Debug.Assert(e.ExpressionKind == DbExpressionKind.All);
        result.Append("NOT EXISTS (");
      }

      SqlSelectStatement filter = VisitFilterExpression(e.Input, e.Predicate, negatePredicate);
      if (filter.Select.IsEmpty)
      {
        AddDefaultColumns(filter);
      }

      result.Append(filter);
      result.Append(")");

      return result;
    }

    /// <summary>
    /// <see cref="DbRefExpression"/> is illegal at this stage
    /// </summary>
    /// <param name="e"></param>
    /// <returns></returns>
    public override ISqlFragment Visit(DbRefExpression e)
    {
      throw new NotSupportedException();
    }

    /// <summary>
    /// <see cref="DbRelationshipNavigationExpression"/> is illegal at this stage
    /// </summary>
    /// <param name="e"></param>
    /// <returns></returns>
    public override ISqlFragment Visit(DbRelationshipNavigationExpression e)
    {
      throw new NotSupportedException();
    }

    /// <summary>
    /// For Sql9 it translates to:
    /// SELECT Y.x1, Y.x2, ..., Y.xn
    /// FROM (
    ///     SELECT X.x1, X.x2, ..., X.xn, row_number() OVER (ORDER BY sk1, sk2, ...) AS [row_number] 
    ///     FROM input as X 
    ///     ) as Y
    /// WHERE Y.[row_number] > count 
    /// ORDER BY sk1, sk2, ...
    /// </summary>
    /// <param name="e"></param>
    /// <returns>A <see cref="SqlBuilder"/></returns>
    public override ISqlFragment Visit(DbSkipExpression e)
    {
      Debug.Assert(e.Count is DbConstantExpression || e.Count is DbParameterReferenceExpression, "DbSkipExpression.Count is of invalid expression type");

      //Visit the input
      Symbol fromSymbol;
      SqlSelectStatement input = VisitInputExpression(e.Input.Expression, e.Input.VariableName, e.Input.VariableType, out fromSymbol);

      // Skip is not compatible with anything that OrderBy is not compatible with, as well as with distinct
      if (!IsCompatible(input, e.ExpressionKind))
      {
        input = CreateNewSelectStatement(input, e.Input.VariableName, e.Input.VariableType, out fromSymbol);
      }

      selectStatementStack.Push(input);
      symbolTable.EnterScope();

      AddFromSymbol(input, e.Input.VariableName, fromSymbol);

      //Add the default columns
      Debug.Assert(input.Select.IsEmpty);
      List<Symbol> inputColumns = AddDefaultColumns(input);

      input.Select.Append(", row_number() OVER (ORDER BY ");
      AddSortKeys(input.Select, e.SortOrder);
      input.Select.Append(") AS ");

      Symbol row_numberSymbol = new Symbol("row_number", null);

      input.Select.Append(row_numberSymbol);

      //The inner statement is complete, its scopes need not be valid any longer
      symbolTable.ExitScope();
      selectStatementStack.Pop();

      //Create the resulting statement 
      //See CreateNewSelectStatement, it is very similar

      SqlSelectStatement result = new SqlSelectStatement();
      result.From.Append("( ");
      result.From.Append(input);
      result.From.AppendLine();
      result.From.Append(") ");

      //Create a symbol for the input
      Symbol resultFromSymbol = null;

      if (input.FromExtents.Count == 1)
      {
        JoinSymbol oldJoinSymbol = input.FromExtents[0] as JoinSymbol;
        if (oldJoinSymbol != null)
        {
          // Note: input.FromExtents will not do, since it might
          // just be an alias of joinSymbol, and we want an actual JoinSymbol.
          JoinSymbol newJoinSymbol = new JoinSymbol(e.Input.VariableName, e.Input.VariableType, oldJoinSymbol.ExtentList);
          // This indicates that the oldStatement is a blocking scope
          // i.e. it hides/renames extent columns
          newJoinSymbol.IsNestedJoin = true;
          newJoinSymbol.ColumnList = inputColumns;
          newJoinSymbol.FlattenedExtentList = oldJoinSymbol.FlattenedExtentList;

          resultFromSymbol = newJoinSymbol;
        }
      }

      if (resultFromSymbol == null)
      {
        // This is just a simple extent/SqlSelectStatement,
        // and we can get the column list from the type.
        resultFromSymbol = new Symbol(e.Input.VariableName, e.Input.VariableType);
      }
      //Add the ORDER BY part
      selectStatementStack.Push(result);
      symbolTable.EnterScope();

      AddFromSymbol(result, e.Input.VariableName, resultFromSymbol);

      //Add the predicate 
      result.Where.Append(resultFromSymbol);
      result.Where.Append(".");
      result.Where.Append(row_numberSymbol);
      result.Where.Append(" > ");
      result.Where.Append(HandaleCountExpression(e.Count));

      AddSortKeys(result.OrderBy, e.SortOrder);

      symbolTable.ExitScope();
      selectStatementStack.Pop();

      return result;
    }

    /// <summary>
    /// <see cref="Visit(DbFilterExpression)"/>
    /// </summary>
    /// <param name="e"></param>
    /// <returns>A <see cref="SqlSelectStatement"/></returns>
    /// <seealso cref="Visit(DbFilterExpression)"/>
    public override ISqlFragment Visit(DbSortExpression e)
    {
      Symbol fromSymbol;
      SqlSelectStatement result = VisitInputExpression(e.Input.Expression, e.Input.VariableName, e.Input.VariableType, out fromSymbol);

      // OrderBy is compatible with Filter
      // and nothing else
      if (!IsCompatible(result, e.ExpressionKind))
      {
        result = CreateNewSelectStatement(result, e.Input.VariableName, e.Input.VariableType, out fromSymbol);
      }

      selectStatementStack.Push(result);
      symbolTable.EnterScope();

      AddFromSymbol(result, e.Input.VariableName, fromSymbol);

      AddSortKeys(result.OrderBy, e.SortOrder);

      symbolTable.ExitScope();
      selectStatementStack.Pop();

      return result;
    }

    /// <summary>
    /// <see cref="DbTreatExpression"/> is illegal at this stage
    /// </summary>
    /// <param name="e"></param>
    /// <returns>A <see cref="SqlBuilder"/></returns>
    public override ISqlFragment Visit(DbTreatExpression e)
    {
      throw new NotSupportedException();
    }

    /// <summary>
    /// This code is shared by <see cref="Visit(DbExceptExpression)"/>
    /// and <see cref="Visit(DbIntersectExpression)"/>
    ///
    /// <see cref="VisitSetOpExpression"/>
    /// Since the left and right expression may not be Sql select statements,
    /// we must wrap them up to look like SQL select statements.
    /// </summary>
    /// <param name="e"></param>
    /// <returns></returns>
    public override ISqlFragment Visit(DbUnionAllExpression e)
    {
      return VisitSetOpExpression(e.Left, e.Right, "UNION ALL");
    }

    /// <summary>
    /// This method determines whether an extent from an outer scope(free variable)
    /// is used in the CurrentSelectStatement.
    ///
    /// An extent in an outer scope, if its symbol is not in the FromExtents
    /// of the CurrentSelectStatement.
    /// </summary>
    /// <param name="e"></param>
    /// <returns>A <see cref="Symbol"/>.</returns>
    public override ISqlFragment Visit(DbVariableReferenceExpression e)
    {
      if (isVarRefSingle)
      {
        throw new NotSupportedException();
        // A DbVariableReferenceExpression has to be a child of DbPropertyExpression or MethodExpression
        // This is also checked in GenerateSql(...) at the end of the visiting.
      }
      isVarRefSingle = true; // This will be reset by DbPropertyExpression or MethodExpression

      Symbol result = symbolTable.Lookup(e.VariableName);
      if (!CurrentSelectStatement.FromExtents.Contains(result))
      {
        CurrentSelectStatement.OuterExtents[result] = true;
      }

      return result;
    }

    #region Visits shared by multiple nodes
    /// <summary>
    /// Aggregates are not visited by the normal visitor walk.
    /// </summary>
    /// <param name="aggregate">The aggreate go be translated</param>
    /// <param name="aggregateArgument">The translated aggregate argument</param>
    /// <returns></returns>
    SqlBuilder VisitAggregate(DbAggregate aggregate, object aggregateArgument)
    {
      SqlBuilder aggregateResult = new SqlBuilder();
      DbFunctionAggregate functionAggregate = aggregate as DbFunctionAggregate;

      if (functionAggregate == null)
      {
        throw new NotSupportedException();
      }

      //The only aggregate function with different name is Big_Count
      //Note: If another such function is to be added, a dictionary should be created
      if (MetadataHelpers.IsCanonicalFunction(functionAggregate.Function)
          && String.Equals(functionAggregate.Function.Name, "BigCount", StringComparison.Ordinal))
      {
        aggregateResult.Append("COUNT_BIG");
      }
      else
      {
        WriteFunctionName(aggregateResult, functionAggregate.Function);
      }

      aggregateResult.Append("(");

      DbFunctionAggregate fnAggr = functionAggregate;
      if ((null != fnAggr) && (fnAggr.Distinct))
      {
        aggregateResult.Append("DISTINCT ");
      }

      aggregateResult.Append(aggregateArgument);

      aggregateResult.Append(")");
      return aggregateResult;
    }


    SqlBuilder VisitBinaryExpression(string op, DbExpression left, DbExpression right)
    {
      SqlBuilder result = new SqlBuilder();
      if (IsComplexExpression(left))
      {
        result.Append("(");
      }

      result.Append(left.Accept(this));

      if (IsComplexExpression(left))
      {
        result.Append(")");
      }

      result.Append(op);

      if (IsComplexExpression(right))
      {
        result.Append("(");
      }

      result.Append(right.Accept(this));

      if (IsComplexExpression(right))
      {
        result.Append(")");
      }

      return result;
    }

    /// <summary>
    /// This is called by the relational nodes.  It does the following
    /// <list>
    /// <item>If the input is not a SqlSelectStatement, it assumes that the input
    /// is a collection expression, and creates a new SqlSelectStatement </item>
    /// </list>
    /// </summary>
    /// <param name="inputExpression"></param>
    /// <param name="inputVarName"></param>
    /// <param name="inputVarType"></param>
    /// <param name="fromSymbol"></param>
    /// <returns>A <see cref="SqlSelectStatement"/> and the main fromSymbol
    /// for this select statement.</returns>
    SqlSelectStatement VisitInputExpression(DbExpression inputExpression,
        string inputVarName, TypeUsage inputVarType, out Symbol fromSymbol)
    {
      SqlSelectStatement result;
      ISqlFragment sqlFragment = inputExpression.Accept(this);
      result = sqlFragment as SqlSelectStatement;

      if (result == null)
      {
        result = new SqlSelectStatement();
        WrapNonQueryExtent(result, sqlFragment, inputExpression.ExpressionKind);
      }

      if (result.FromExtents.Count == 0)
      {
        // input was an extent
        fromSymbol = new Symbol(inputVarName, inputVarType);
      }
      else if (result.FromExtents.Count == 1)
      {
        // input was Filter/GroupBy/Project/OrderBy
        // we are likely to reuse this statement.
        fromSymbol = result.FromExtents[0];
      }
      else
      {
        // input was a join.
        // we are reusing the select statement produced by a Join node
        // we need to remove the original extents, and replace them with a
        // new extent with just the Join symbol.
        JoinSymbol joinSymbol = new JoinSymbol(inputVarName, inputVarType, result.FromExtents);
        joinSymbol.FlattenedExtentList = result.AllJoinExtents;

        fromSymbol = joinSymbol;
        result.FromExtents.Clear();
        result.FromExtents.Add(fromSymbol);
      }

      return result;
    }

    /// <summary>
    /// <see cref="Visit(DbIsEmptyExpression)"/>
    /// </summary>
    /// <param name="e"></param>
    /// <param name="negate">Was the parent a DbNotExpression?</param>
    /// <returns></returns>
    SqlBuilder VisitIsEmptyExpression(DbIsEmptyExpression e, bool negate)
    {
      SqlBuilder result = new SqlBuilder();
      if (!negate)
      {
        result.Append(" NOT");
      }
      result.Append(" EXISTS (");
      result.Append(VisitExpressionEnsureSqlStatement(e.Argument));
      result.AppendLine();
      result.Append(")");

      return result;
    }


    /// <summary>
    /// Translate a NewInstance(Element(X)) expression into
    ///   "select top(1) * from X"
    /// </summary>
    /// <param name="e"></param>
    /// <returns></returns>
    private ISqlFragment VisitCollectionConstructor(DbNewInstanceExpression e)
    {
      Debug.Assert(e.Arguments.Count <= 1);

      if (e.Arguments.Count == 1 && e.Arguments[0].ExpressionKind == DbExpressionKind.Element)
      {
        DbElementExpression elementExpr = e.Arguments[0] as DbElementExpression;
        SqlSelectStatement result = VisitExpressionEnsureSqlStatement(elementExpr.Argument);

        if (!IsCompatible(result, DbExpressionKind.Element))
        {
          Symbol fromSymbol;
          TypeUsage inputType = MetadataHelpers.GetElementTypeUsage(elementExpr.Argument.ResultType);

          result = CreateNewSelectStatement(result, "element", inputType, out fromSymbol);
          AddFromSymbol(result, "element", fromSymbol, false);
        }
        result.Top = new TopClause(1, false);
        return result;
      }


      // Otherwise simply build this out as a union-all ladder
      CollectionType collectionType = MetadataHelpers.GetEdmType<CollectionType>(e.ResultType);
      Debug.Assert(collectionType != null);
      bool isScalarElement = MetadataHelpers.IsPrimitiveType(collectionType.TypeUsage);

      SqlBuilder resultSql = new SqlBuilder();
      string separator = "";

      // handle empty table
      if (e.Arguments.Count == 0)
      {
        Debug.Assert(isScalarElement);
        resultSql.Append(" SELECT NULL");
        resultSql.Append(" AS X FROM (SELECT 1) AS Y WHERE 1=0");
      }

      foreach (DbExpression arg in e.Arguments)
      {
        resultSql.Append(separator);
        resultSql.Append(" SELECT ");
        resultSql.Append(arg.Accept(this));
        // For scalar elements, no alias is appended yet. Add this.
        if (isScalarElement)
        {
          resultSql.Append(" AS X ");
        }
        separator = " UNION ALL ";
      }

      return resultSql;
    }


    /// <summary>
    /// <see cref="Visit(DbIsNullExpression)"/>
    /// </summary>
    /// <param name="e"></param>
    /// <param name="negate">Was the parent a DbNotExpression?</param>
    /// <returns></returns>
    SqlBuilder VisitIsNullExpression(DbIsNullExpression e, bool negate)
    {
      SqlBuilder result = new SqlBuilder();
      result.Append(e.Argument.Accept(this));
      if (!negate)
      {
        result.Append(" IS NULL");
      }
      else
      {
        result.Append(" IS NOT NULL");
      }

      return result;
    }

    /// <summary>
    /// This handles the processing of join expressions.
    /// The extents on a left spine are flattened, while joins
    /// not on the left spine give rise to new nested sub queries.
    ///
    /// Joins work differently from the rest of the visiting, in that
    /// the parent (i.e. the join node) creates the SqlSelectStatement
    /// for the children to use.
    ///
    /// The "parameter" IsInJoinContext indicates whether a child extent should
    /// add its stuff to the existing SqlSelectStatement, or create a new SqlSelectStatement
    /// By passing true, we ask the children to add themselves to the parent join,
    /// by passing false, we ask the children to create new Select statements for
    /// themselves.
    ///
    /// This method is called from <see cref="Visit(DbApplyExpression)"/> and
    /// <see cref="Visit(DbJoinExpression)"/>.
    /// </summary>
    /// <param name="inputs"></param>
    /// <param name="joinKind"></param>
    /// <param name="joinString"></param>
    /// <param name="joinCondition"></param>
    /// <returns> A <see cref="SqlSelectStatement"/></returns>
    ISqlFragment VisitJoinExpression(IList<DbExpressionBinding> inputs, DbExpressionKind joinKind,
        string joinString, DbExpression joinCondition)
    {
      SqlSelectStatement result;
      // If the parent is not a join( or says that it is not),
      // we should create a new SqlSelectStatement.
      // otherwise, we add our child extents to the parent's FROM clause.
      if (!IsParentAJoin)
      {
        result = new SqlSelectStatement();
        result.AllJoinExtents = new List<Symbol>();
        selectStatementStack.Push(result);
      }
      else
      {
        result = CurrentSelectStatement;
      }

      // Process each of the inputs, and then the joinCondition if it exists.
      // It would be nice if we could call VisitInputExpression - that would
      // avoid some code duplication
      // but the Join postprocessing is messy and prevents this reuse.
      symbolTable.EnterScope();

      string separator = "";
      bool isLeftMostInput = true;
      int inputCount = inputs.Count;
      for (int idx = 0; idx < inputCount; idx++)
      {
        DbExpressionBinding input = inputs[idx];

        if (separator != "")
        {
          result.From.AppendLine();
        }
        result.From.Append(separator + " ");
        // Change this if other conditions are required
        // to force the child to produce a nested SqlStatement.
        bool needsJoinContext = (input.Expression.ExpressionKind == DbExpressionKind.Scan)
                                || (isLeftMostInput &&
                                    (IsJoinExpression(input.Expression)
                                     || IsApplyExpression(input.Expression)))
                                ;

        isParentAJoinStack.Push(needsJoinContext ? true : false);
        // if the child reuses our select statement, it will append the from
        // symbols to our FromExtents list.  So, we need to remember the
        // start of the child's entries.
        int fromSymbolStart = result.FromExtents.Count;

        ISqlFragment fromExtentFragment = input.Expression.Accept(this);

        isParentAJoinStack.Pop();

        ProcessJoinInputResult(fromExtentFragment, result, input, fromSymbolStart);
        separator = joinString;

        isLeftMostInput = false;
      }

      // Visit the on clause/join condition.
      switch (joinKind)
      {
        case DbExpressionKind.FullOuterJoin:
        case DbExpressionKind.InnerJoin:
        case DbExpressionKind.LeftOuterJoin:
          result.From.Append(" ON ");
          isParentAJoinStack.Push(false);
          result.From.Append(joinCondition.Accept(this));
          isParentAJoinStack.Pop();
          break;
      }

      symbolTable.ExitScope();

      if (!IsParentAJoin)
      {
        selectStatementStack.Pop();
      }

      return result;
    }

    /// <summary>
    /// This is called from <see cref="VisitJoinExpression"/>.
    ///
    /// This is responsible for maintaining the symbol table after visiting
    /// a child of a join expression.
    ///
    /// The child's sql statement may need to be completed.
    ///
    /// The child's result could be one of
    /// <list type="number">
    /// <item>The same as the parent's - this is treated specially.</item>
    /// <item>A sql select statement, which may need to be completed</item>
    /// <item>An extent - just copy it to the from clause</item>
    /// <item>Anything else (from a collection-valued expression) -
    /// unnest and copy it.</item>
    /// </list>
    ///
    /// If the input was a Join, we need to create a new join symbol,
    /// otherwise, we create a normal symbol.
    ///
    /// We then call AddFromSymbol to add the AS clause, and update the symbol table.
    ///
    ///
    ///
    /// If the child's result was the same as the parent's, we have to clean up
    /// the list of symbols in the FromExtents list, since this contains symbols from
    /// the children of both the parent and the child.
    /// The happens when the child visited is a Join, and is the leftmost child of
    /// the parent.
    /// </summary>
    /// <param name="fromExtentFragment"></param>
    /// <param name="result"></param>
    /// <param name="input"></param>
    /// <param name="fromSymbolStart"></param>
    void ProcessJoinInputResult(ISqlFragment fromExtentFragment, SqlSelectStatement result,
        DbExpressionBinding input, int fromSymbolStart)
    {
      Symbol fromSymbol = null;

      if (result != fromExtentFragment)
      {
        // The child has its own select statement, and is not reusing
        // our select statement.
        // This should look a lot like VisitInputExpression().
        SqlSelectStatement sqlSelectStatement = fromExtentFragment as SqlSelectStatement;
        if (sqlSelectStatement != null)
        {
          if (sqlSelectStatement.Select.IsEmpty)
          {
            List<Symbol> columns = AddDefaultColumns(sqlSelectStatement);

            if (IsJoinExpression(input.Expression)
                || IsApplyExpression(input.Expression))
            {
              List<Symbol> extents = sqlSelectStatement.FromExtents;
              JoinSymbol newJoinSymbol = new JoinSymbol(input.VariableName, input.VariableType, extents);
              newJoinSymbol.IsNestedJoin = true;
              newJoinSymbol.ColumnList = columns;

              fromSymbol = newJoinSymbol;
            }
            else
            {
              // this is a copy of the code in CreateNewSelectStatement.

              // if the oldStatement has a join as its input, ...
              // clone the join symbol, so that we "reuse" the
              // join symbol.  Normally, we create a new symbol - see the next block
              // of code.
              JoinSymbol oldJoinSymbol = sqlSelectStatement.FromExtents[0] as JoinSymbol;
              if (oldJoinSymbol != null)
              {
                // Note: sqlSelectStatement.FromExtents will not do, since it might
                // just be an alias of joinSymbol, and we want an actual JoinSymbol.
                JoinSymbol newJoinSymbol = new JoinSymbol(input.VariableName, input.VariableType, oldJoinSymbol.ExtentList);
                // This indicates that the sqlSelectStatement is a blocking scope
                // i.e. it hides/renames extent columns
                newJoinSymbol.IsNestedJoin = true;
                newJoinSymbol.ColumnList = columns;
                newJoinSymbol.FlattenedExtentList = oldJoinSymbol.FlattenedExtentList;

                fromSymbol = newJoinSymbol;
              }
            }

          }
          result.From.Append(" (");
          result.From.Append(sqlSelectStatement);
          result.From.Append(" )");
        }
        else if (input.Expression is DbScanExpression)
        {
          result.From.Append(fromExtentFragment);
        }
        else // bracket it
        {
          WrapNonQueryExtent(result, fromExtentFragment, input.Expression.ExpressionKind);
        }

        if (fromSymbol == null) // i.e. not a join symbol
        {
          fromSymbol = new Symbol(input.VariableName, input.VariableType);
        }


        AddFromSymbol(result, input.VariableName, fromSymbol);
        result.AllJoinExtents.Add(fromSymbol);
      }
      else // result == fromExtentFragment.  The child extents have been merged into the parent's.
      {
        // we are adding extents to the current sql statement via flattening.
        // We are replacing the child's extents with a single Join symbol.
        // The child's extents are all those following the index fromSymbolStart.
        //
        List<Symbol> extents = new List<Symbol>();

        // We cannot call extents.AddRange, since the is no simple way to
        // get the range of symbols fromSymbolStart..result.FromExtents.Count
        // from result.FromExtents.
        // We copy these symbols to create the JoinSymbol later.
        for (int i = fromSymbolStart; i < result.FromExtents.Count; ++i)

        {
          extents.Add(result.FromExtents[i]);
        }
        result.FromExtents.RemoveRange(fromSymbolStart, result.FromExtents.Count - fromSymbolStart);
        fromSymbol = new JoinSymbol(input.VariableName, input.VariableType, extents);
        result.FromExtents.Add(fromSymbol);
        // this Join Symbol does not have its own select statement, so we
        // do not set IsNestedJoin


        // We do not call AddFromSymbol(), since we do not want to add
        // "AS alias" to the FROM clause- it has been done when the extent was added earlier.
        symbolTable.Add(input.VariableName, fromSymbol);
      }
    }

    /// <summary>
    /// We assume that this is only called as a child of a Project.
    ///
    /// This replaces <see cref="Visit(DbNewInstanceExpression)"/>, since
    /// we do not allow DbNewInstanceExpression as a child of any node other than
    /// DbProjectExpression.
    ///
    /// We write out the translation of each of the columns in the record.
    /// </summary>
    /// <param name="e"></param>

    /// <returns>A <see cref="SqlBuilder"/></returns>
    ISqlFragment VisitNewInstanceExpression(DbNewInstanceExpression e)
    {
      SqlBuilder result = new SqlBuilder();
      RowType rowType = e.ResultType.EdmType as RowType;

      if (null != rowType)
      {
        _typeDefs.Length = 0;
        ReadOnlyMetadataCollection<EdmProperty> members = rowType.Properties;
        string separator = "";
        for (int i = 0; i < e.Arguments.Count; ++i)
        {
          DbExpression argument = e.Arguments[i];
          if (MetadataHelpers.IsRowType(argument.ResultType))
          {
            // We do not support nested records or other complex objects.
            throw new NotSupportedException();
          }

          EdmProperty member = members[i];
          _typeDefs.Append(separator);
          _typeDefs.Append(GetSqlPrimitiveType(member.TypeUsage));
          result.Append(separator);
          result.AppendLine();
          result.Append(argument.Accept(this));
          result.Append(" AS ");
          result.Append(QuoteIdentifier(member.Name));
          separator = ", ";
        }
      }
      else
      {
        //
        // Types other then RowType (such as UDTs for instance) are not supported.
        //
        throw new NotSupportedException();
      }

      return result;
    }

    ISqlFragment VisitSetOpExpression(DbExpression left, DbExpression right, string separator)
    {

      SqlSelectStatement leftSelectStatement = VisitExpressionEnsureSqlStatement(left);
      SqlSelectStatement rightSelectStatement = VisitExpressionEnsureSqlStatement(right);

      SqlBuilder setStatement = new SqlBuilder();
      setStatement.Append(leftSelectStatement);
      setStatement.AppendLine();
      setStatement.Append(separator); // e.g. UNION ALL
      setStatement.AppendLine();
      setStatement.Append(rightSelectStatement);

      return setStatement;
    }


    #endregion


    #region Function Handling Helpers
    /// <summary>
    /// Determines whether the given function is a built-in function that requires special handling
    /// </summary>
    /// <param name="e"></param>
    /// <returns></returns>
    private bool IsSpecialBuiltInFunction(DbFunctionExpression e)
    {
      return IsBuiltinFunction(e.Function) && _builtInFunctionHandlers.ContainsKey(e.Function.Name);
    }

    /// <summary>
    /// Determines whether the given function is a canonical function that requires special handling
    /// </summary>
    /// <param name="e"></param>
    /// <returns></returns>
    private bool IsSpecialCanonicalFunction(DbFunctionExpression e)
    {
      return MetadataHelpers.IsCanonicalFunction(e.Function) && _canonicalFunctionHandlers.ContainsKey(e.Function.Name);
    }

    /// <summary>
    /// Default handling for functions
    /// Translates them to FunctionName(arg1, arg2, ..., argn)
    /// </summary>
    /// <param name="e"></param>
    /// <returns></returns>
    private ISqlFragment HandleFunctionDefault(DbFunctionExpression e)
    {
      SqlBuilder result = new SqlBuilder();
      WriteFunctionName(result, e.Function);
      HandleFunctionArgumentsDefault(e, result);
      return result;
    }

    /// <summary>
    /// Default handling for functions with a given name.
    /// Translates them to functionName(arg1, arg2, ..., argn)
    /// </summary>
    /// <param name="e"></param>
    /// <param name="functionName"></param>
    /// <returns></returns>
    private ISqlFragment HandleFunctionDefaultGivenName(DbFunctionExpression e, string functionName)
    {
      SqlBuilder result = new SqlBuilder();
      result.Append(functionName);
      HandleFunctionArgumentsDefault(e, result);
      return result;
    }

    /// <summary>
    /// Default handling on function arguments
    /// Appends the list of arguments to the given result
    /// If the function is niladic it does not append anything,
    /// otherwise it appends (arg1, arg2, ..., argn)
    /// </summary>
    /// <param name="e"></param>
    /// <param name="result"></param>
    private void HandleFunctionArgumentsDefault(DbFunctionExpression e, SqlBuilder result)
    {
      bool isNiladicFunction = MetadataHelpers.TryGetValueForMetadataProperty<bool>(e.Function, "NiladicFunctionAttribute");
      if (isNiladicFunction && e.Arguments.Count > 0)
      {
        throw new InvalidOperationException("Niladic functions cannot have parameters");
      }

      if (!isNiladicFunction)
      {
        result.Append("(");
        string separator = "";
        foreach (DbExpression arg in e.Arguments)
        {
          result.Append(separator);
          result.Append(arg.Accept(this));
          separator = ", ";
        }
        result.Append(")");
      }
    }

    /// <summary>
    /// Handler for special built in functions
    /// </summary>
    /// <param name="e"></param>
    /// <returns></returns>
    private ISqlFragment HandleSpecialBuiltInFunction(DbFunctionExpression e)
    {
      return HandleSpecialFunction(_builtInFunctionHandlers, e);
    }

    /// <summary>
    /// Handler for special canonical functions
    /// </summary>
    /// <param name="e"></param>
    /// <returns></returns>
    private ISqlFragment HandleSpecialCanonicalFunction(DbFunctionExpression e)
    {
      return HandleSpecialFunction(_canonicalFunctionHandlers, e);
    }

    /// <summary>
    /// Dispatches the special function processing to the appropriate handler
    /// </summary>
    /// <param name="handlers"></param>
    /// <param name="e"></param>
    /// <returns></returns>
    private ISqlFragment HandleSpecialFunction(Dictionary<string, FunctionHandler> handlers, DbFunctionExpression e)
    {
      if (!handlers.ContainsKey(e.Function.Name))
        throw new InvalidOperationException("Special handling should be called only for functions in the list of special functions");

      return handlers[e.Function.Name](this, e);
    }

    /// <summary>
    /// Handles functions that are translated into TSQL operators.
    /// The given function should have one or two arguments. 
    /// Functions with one arguemnt are translated into 
    ///     op arg
    /// Functions with two arguments are translated into
    ///     arg0 op arg1
    /// Also, the arguments can be optionaly enclosed in parethesis
    /// </summary>
    /// <param name="e"></param>
    /// <param name="parenthesiseArguments">Whether the arguments should be enclosed in parethesis</param>
    /// <returns></returns>
    private ISqlFragment HandleSpecialFunctionToOperator(DbFunctionExpression e, bool parenthesiseArguments)
    {
      SqlBuilder result = new SqlBuilder();
      Debug.Assert(e.Arguments.Count > 0 && e.Arguments.Count <= 2, "There should be 1 or 2 arguments for operator");

      if (e.Arguments.Count > 1)
      {
        if (parenthesiseArguments)
        {
          result.Append("(");
        }
        result.Append(e.Arguments[0].Accept(this));
        if (parenthesiseArguments)
        {
          result.Append(")");
        }
      }
      result.Append(" ");
      Debug.Assert(_functionNameToOperatorDictionary.ContainsKey(e.Function.Name), "The function can not be mapped to an operator");
      result.Append(_functionNameToOperatorDictionary[e.Function.Name]);
      result.Append(" ");

      if (parenthesiseArguments)
      {
        result.Append("(");
      }
      result.Append(e.Arguments[e.Arguments.Count - 1].Accept(this));
      if (parenthesiseArguments)
      {
        result.Append(")");
      }
      return result;
    }


    /// <summary>
    /// <see cref="HandleSpecialFunctionToOperator"></see>
    /// </summary>
    /// <param name="sqlgen"></param>
    /// <param name="e"></param>
    /// <returns></returns>
    private static ISqlFragment HandleConcatFunction(SqlGenerator sqlgen, DbFunctionExpression e)
    {
      return sqlgen.HandleSpecialFunctionToOperator(e, false);
    }

    /// <summary>
    /// <see cref="HandleSpecialFunctionToOperator"></see>
    /// </summary>
    /// <param name="sqlgen"></param>
    /// <param name="e"></param>
    /// <returns></returns>
    private static ISqlFragment HandleCanonicalFunctionBitwise(SqlGenerator sqlgen, DbFunctionExpression e)
    {
      return sqlgen.HandleSpecialFunctionToOperator(e, true);
    }

    /// <summary>
    /// Handles special case in which datapart 'type' parameter is present. all the functions
    /// handles here have *only* the 1st parameter as datepart. datepart value is passed along
    /// the QP as string and has to be expanded as TSQL keyword.
    /// </summary>
    /// <param name="sqlgen"></param>
    /// <param name="e"></param>
    /// <returns></returns>
    private static ISqlFragment HandleDatepartDateFunction(SqlGenerator sqlgen, DbFunctionExpression e)
    {
      Debug.Assert(e.Arguments.Count > 0, "e.Arguments.Count > 0");

      DbConstantExpression constExpr = e.Arguments[0] as DbConstantExpression;
      if (null == constExpr)
      {
        throw new InvalidOperationException(String.Format("DATEPART argument to function '{0}.{1}' must be a literal string", e.Function.NamespaceName, e.Function.Name));
      }

      string datepart = constExpr.Value as string;
      if (null == datepart)
      {
        throw new InvalidOperationException(String.Format("DATEPART argument to function '{0}.{1}' must be a literal string", e.Function.NamespaceName, e.Function.Name));
      }

      SqlBuilder result = new SqlBuilder();

      //
      // check if datepart value is valid
      //
      if (!_datepartKeywords.ContainsKey(datepart))
      {
        throw new InvalidOperationException(String.Format("{0}' is not a valid value for DATEPART argument in '{1}.{2}' function", datepart, e.Function.NamespaceName, e.Function.Name));
      }

      //
      // finaly, expand the function name
      //
      sqlgen.WriteFunctionName(result, e.Function);
      result.Append("(");

      // expand the datepart literal as tsql kword
      result.Append(datepart);
      string separator = ", ";

      // expand remaining arguments
      for (int i = 1; i < e.Arguments.Count; i++)
      {
        result.Append(separator);
        result.Append(e.Arguments[i].Accept(sqlgen));
      }

      result.Append(")");

      return result;
    }

    /// <summary>
    /// DateAdd(datetime, secondsToAdd) -> DATEADD ( seconds , number,  date)
    /// </summary>
    /// <param name="sqlgen"></param>
    /// <param name="e"></param>
    /// <returns></returns>
    private static ISqlFragment HandleCanonicalFunctionDateAdd(SqlGenerator sqlgen, DbFunctionExpression e)
    {
      SqlBuilder result = new SqlBuilder();
      result.Append("DATEADD (second");

      Debug.Assert(e.Arguments.Count == 2, "Canonical datepart functions should have exactly two arguments");

      for (int i = 1; i >= 0; i--)
      {
        result.Append(", ");
        result.Append(e.Arguments[i].Accept(sqlgen));
      }

      result.Append(")");

      return result;
    }

    /// <summary>
    /// DateSubtract(datetime1, datetime2) -> DATEDIFF ( seconds , startdate , enddate ) 
    /// </summary>
    /// <param name="sqlgen"></param>
    /// <param name="e"></param>
    /// <returns></returns>
    private static ISqlFragment HandleCanonicalFunctionDateSubtract(SqlGenerator sqlgen, DbFunctionExpression e)
    {
      SqlBuilder result = new SqlBuilder();
      result.Append("DATEDIFF (second");

      Debug.Assert(e.Arguments.Count == 2, "Canonical datepart functions should have exactly two arguments");

      for (int i = 0; i < 2; i++)
      {
        result.Append(", ");
        result.Append(e.Arguments[i].Accept(sqlgen));
      }

      result.Append(")");

      return result;
    }

    /// <summary>
    /// Handler for canonical funcitons for extracting date parts. 
    /// For example:
    ///     Year(date) -> DATEPART( year, date)
    /// </summary>
    /// <param name="sqlgen"></param>
    /// <param name="e"></param>
    /// <returns></returns>
    private static ISqlFragment HandleCanonicalFunctionDatepart(SqlGenerator sqlgen, DbFunctionExpression e)
    {
      SqlBuilder result = new SqlBuilder();
      result.Append("DATEPART (");
      result.Append(e.Function.Name.ToLowerInvariant());
      result.Append(", ");

      Debug.Assert(e.Arguments.Count == 1, "Canonical datepart functions should have exactly one argument");
      result.Append(e.Arguments[0].Accept(sqlgen));

      result.Append(")");

      return result;
    }

    /// <summary>
    ///  Function rename IndexOf -> CHARINDEX
    /// </summary>
    /// <param name="sqlgen"></param>
    /// <param name="e"></param>
    /// <returns></returns>
    private static ISqlFragment HandleCanonicalFunctionIndexOf(SqlGenerator sqlgen, DbFunctionExpression e)
    {
      return sqlgen.HandleFunctionDefaultGivenName(e, "CHARINDEX");
    }

    /// <summary>
    ///  Function rename NewGuid -> NEWID
    /// </summary>
    /// <param name="sqlgen"></param>
    /// <param name="e"></param>
    /// <returns></returns>
    private static ISqlFragment HandleCanonicalFunctionNewGuid(SqlGenerator sqlgen, DbFunctionExpression e)
    {
      return sqlgen.HandleFunctionDefaultGivenName(e, "NEWID");
    }

    /// <summary>
    ///  Length(arg) -> LEN(arg + '.') - LEN('.')
    /// </summary>
    /// <param name="sqlgen"></param>
    /// <param name="e"></param>
    /// <returns></returns>
    private static ISqlFragment HandleCanonicalFunctionLength(SqlGenerator sqlgen, DbFunctionExpression e)
    {
      SqlBuilder result = new SqlBuilder();

      result.Append("LEN(");

      Debug.Assert(e.Arguments.Count == 1, "Len should have one argument");
      result.Append(e.Arguments[0].Accept(sqlgen));

      result.Append(")");
      //result.Append(" + '.') - LEN('.')");

      return result;
    }

    /// <summary>
    /// Round(numericExpression) -> Round(numericExpression, 0);
    /// </summary>
    /// <param name="sqlgen"></param>
    /// <param name="e"></param>
    /// <returns></returns>
    private static ISqlFragment HandleCanonicalFunctionRound(SqlGenerator sqlgen, DbFunctionExpression e)
    {
      SqlBuilder result = new SqlBuilder();

      result.Append("ROUND(");

      Debug.Assert(e.Arguments.Count == 1, "Round should have one argument");
      result.Append(e.Arguments[0].Accept(sqlgen));

      result.Append(", 0)");

      return result;
    }

    /// <summary>
    /// TRIM(string) -> LTRIM(RTRIM(string))
    /// </summary>
    /// <param name="sqlgen"></param>
    /// <param name="e"></param>
    /// <returns></returns>
    private static ISqlFragment HandleCanonicalFunctionTrim(SqlGenerator sqlgen, DbFunctionExpression e)
    {
      SqlBuilder result = new SqlBuilder();

      result.Append("LTRIM(RTRIM(");

      Debug.Assert(e.Arguments.Count == 1, "Trim should have one argument");
      result.Append(e.Arguments[0].Accept(sqlgen));

      result.Append("))");

      return result;
    }

    /// <summary>
    ///  Function rename ToLower -> LOWER
    /// </summary>
    /// <param name="sqlgen"></param>
    /// <param name="e"></param>
    /// <returns></returns>
    private static ISqlFragment HandleCanonicalFunctionToLower(SqlGenerator sqlgen, DbFunctionExpression e)
    {
      return sqlgen.HandleFunctionDefaultGivenName(e, "LOWER");
    }

    /// <summary>
    ///  Function rename ToUpper -> UPPER
    /// </summary>
    /// <param name="sqlgen"></param>
    /// <param name="e"></param>
    /// <returns></returns>
    private static ISqlFragment HandleCanonicalFunctionToUpper(SqlGenerator sqlgen, DbFunctionExpression e)
    {
      return sqlgen.HandleFunctionDefaultGivenName(e, "UPPER");
    }

    #endregion


    #endregion

    #region Helper methods for the DbExpressionVisitor
    /// <summary>
    /// <see cref="AddDefaultColumns"/>
    /// Add the column names from the referenced extent/join to the
    /// select statement.
    ///
    /// If the symbol is a JoinSymbol, we recursively visit all the extents,
    /// halting at real extents and JoinSymbols that have an associated SqlSelectStatement.
    ///
    /// The column names for a real extent can be derived from its type.
    /// The column names for a Join Select statement can be got from the
    /// list of columns that was created when the Join's select statement
    /// was created.
    ///
    /// We do the following for each column.
    /// <list type="number">
    /// <item>Add the SQL string for each column to the SELECT clause</item>
    /// <item>Add the column to the list of columns - so that it can
    /// become part of the "type" of a JoinSymbol</item>
    /// <item>Check if the column name collides with a previous column added
    /// to the same select statement.  Flag both the columns for renaming if true.</item>
    /// <item>Add the column to a name lookup dictionary for collision detection.</item>
    /// </list>
    /// </summary>
    /// <param name="selectStatement">The select statement that started off as SELECT *</param>
    /// <param name="symbol">The symbol containing the type information for
    /// the columns to be added.</param>
    /// <param name="columnList">Columns that have been added to the Select statement.
    /// This is created in <see cref="AddDefaultColumns"/>.</param>
    /// <param name="columnDictionary">A dictionary of the columns above.</param>
    /// <param name="separator">Comma or nothing, depending on whether the SELECT
    /// clause is empty.</param>
    void AddColumns(SqlSelectStatement selectStatement, Symbol symbol,
        List<Symbol> columnList, Dictionary<string, Symbol> columnDictionary, ref string separator)
    {
      JoinSymbol joinSymbol = symbol as JoinSymbol;
      if (joinSymbol != null)
      {
        if (!joinSymbol.IsNestedJoin)
        {
          // Recurse if the join symbol is a collection of flattened extents
          foreach (Symbol sym in joinSymbol.ExtentList)
          {
            // if sym is ScalarType means we are at base case in the
            // recursion and there are not columns to add, just skip
            if (MetadataHelpers.IsPrimitiveType(sym.Type))
            {
              continue;
            }

            AddColumns(selectStatement, sym, columnList, columnDictionary, ref separator);
          }
        }
        else
        {
          foreach (Symbol joinColumn in joinSymbol.ColumnList)
          {
            // we write tableName.columnName
            // rather than tableName.columnName as alias
            // since the column name is unique (by the way we generate new column names)
            //
            // We use the symbols for both the table and the column,
            // since they are subject to renaming.
            selectStatement.Select.Append(separator);
            selectStatement.Select.Append(symbol);
            selectStatement.Select.Append(".");
            selectStatement.Select.Append(joinColumn);

            // check for name collisions.  If there is,
            // flag both the colliding symbols.
            if (columnDictionary.ContainsKey(joinColumn.Name))
            {
              columnDictionary[joinColumn.Name].NeedsRenaming = true; // the original symbol
              joinColumn.NeedsRenaming = true; // the current symbol.
            }
            else
            {
              columnDictionary[joinColumn.Name] = joinColumn;
            }

            columnList.Add(joinColumn);

            separator = ", ";
          }
        }
      }
      else
      {
        // This is a non-join extent/select statement, and the CQT type has
        // the relevant column information.

        // The type could be a record type(e.g. Project(...),
        // or an entity type ( e.g. EntityExpression(...)
        // so, we check whether it is a structuralType.

        // Consider an expression of the form J(a, b=P(E))
        // The inner P(E) would have been translated to a SQL statement
        // We should not use the raw names from the type, but the equivalent
        // symbols (they are present in symbol.Columns) if they exist.
        //
        // We add the new columns to the symbol's columns if they do
        // not already exist.
        //

        foreach (EdmProperty property in MetadataHelpers.GetProperties(symbol.Type))
        {
          string recordMemberName = property.Name;
          // Since all renaming happens in the second phase
          // we lose nothing by setting the next column name index to 0
          // many times.
          allColumnNames[recordMemberName] = 0;

          // Create a new symbol/reuse existing symbol for the column
          Symbol columnSymbol;
          if (!symbol.Columns.TryGetValue(recordMemberName, out columnSymbol))
          {
            // we do not care about the types of columns, so we pass null
            // when construction the symbol.
            columnSymbol = new Symbol(recordMemberName, null);
            symbol.Columns.Add(recordMemberName, columnSymbol);
          }

          selectStatement.Select.Append(separator);
          selectStatement.Select.Append(symbol);
          selectStatement.Select.Append(".");

          // We use the actual name before the "AS", the new name goes
          // after the AS.
          selectStatement.Select.Append(QuoteIdentifier(recordMemberName));

          selectStatement.Select.Append(" AS ");
          selectStatement.Select.Append(columnSymbol);

          // Check for column name collisions.
          if (columnDictionary.ContainsKey(recordMemberName))
          {
            columnDictionary[recordMemberName].NeedsRenaming = true;
            columnSymbol.NeedsRenaming = true;
          }
          else
          {
            columnDictionary[recordMemberName] = symbol.Columns[recordMemberName];
          }

          columnList.Add(columnSymbol);

          separator = ", ";
        }
      }
    }

    /// <summary>
    /// Expands Select * to "select the_list_of_columns"
    /// If the columns are taken from an extent, they are written as
    /// {original_column_name AS Symbol(original_column)} to allow renaming.
    ///
    /// If the columns are taken from a Join, they are written as just
    /// {original_column_name}, since there cannot be a name collision.
    ///
    /// We concatenate the columns from each of the inputs to the select statement.
    /// Since the inputs may be joins that are flattened, we need to recurse.
    /// The inputs are inferred from the symbols in FromExtents.
    /// </summary>
    /// <param name="selectStatement"></param>
    /// <returns></returns>
    List<Symbol> AddDefaultColumns(SqlSelectStatement selectStatement)
    {
      // This is the list of columns added in this select statement
      // This forms the "type" of the Select statement, if it has to
      // be expanded in another SELECT *
      List<Symbol> columnList = new List<Symbol>();

      // A lookup for the previous set of columns to aid column name
      // collision detection.
      Dictionary<string, Symbol> columnDictionary = new Dictionary<string, Symbol>(StringComparer.OrdinalIgnoreCase);

      string separator = "";
      // The Select should usually be empty before we are called,
      // but we do not mind if it is not.
      if (!selectStatement.Select.IsEmpty)
      {
        separator = ", ";
      }

      foreach (Symbol symbol in selectStatement.FromExtents)
      {
        AddColumns(selectStatement, symbol, columnList, columnDictionary, ref separator);
      }

      return columnList;
    }

    /// <summary>
    /// <see cref="AddFromSymbol(SqlSelectStatement, string, Symbol, bool)"/>
    /// </summary>
    /// <param name="selectStatement"></param>
    /// <param name="inputVarName"></param>
    /// <param name="fromSymbol"></param>
    void AddFromSymbol(SqlSelectStatement selectStatement, string inputVarName, Symbol fromSymbol)
    {
      AddFromSymbol(selectStatement, inputVarName, fromSymbol, true);
    }

    /// <summary>
    /// This method is called after the input to a relational node is visited.
    /// <see cref="Visit(DbProjectExpression)"/> and <see cref="ProcessJoinInputResult"/>
    /// There are 2 scenarios
    /// <list type="number">
    /// <item>The fromSymbol is new i.e. the select statement has just been
    /// created, or a join extent has been added.</item>
    /// <item>The fromSymbol is old i.e. we are reusing a select statement.</item>
    /// </list>
    ///
    /// If we are not reusing the select statement, we have to complete the
    /// FROM clause with the alias
    /// <code>
    /// -- if the input was an extent
    /// FROM = [SchemaName].[TableName]
    /// -- if the input was a Project
    /// FROM = (SELECT ... FROM ... WHERE ...)
    /// </code>
    ///
    /// These become
    /// <code>
    /// -- if the input was an extent
    /// FROM = [SchemaName].[TableName] AS alias
    /// -- if the input was a Project
    /// FROM = (SELECT ... FROM ... WHERE ...) AS alias
    /// </code>
    /// and look like valid FROM clauses.
    ///
    /// Finally, we have to add the alias to the global list of aliases used,
    /// and also to the current symbol table.
    /// </summary>
    /// <param name="selectStatement"></param>
    /// <param name="inputVarName">The alias to be used.</param>
    /// <param name="fromSymbol"></param>
    /// <param name="addToSymbolTable"></param>
    void AddFromSymbol(SqlSelectStatement selectStatement, string inputVarName, Symbol fromSymbol, bool addToSymbolTable)
    {
      // the first check is true if this is a new statement
      // the second check is true if we are in a join - we do not
      // check if we are in a join context.
      // We do not want to add "AS alias" if it has been done already
      // e.g. when we are reusing the Sql statement.
      if (selectStatement.FromExtents.Count == 0 || fromSymbol != selectStatement.FromExtents[0])
      {
        selectStatement.FromExtents.Add(fromSymbol);
        selectStatement.From.Append(" AS ");
        selectStatement.From.Append(fromSymbol);

        // We have this inside the if statement, since
        // we only want to add extents that are actually used.
        allExtentNames[fromSymbol.Name] = 0;
      }

      if (addToSymbolTable)
      {
        symbolTable.Add(inputVarName, fromSymbol);
      }
    }

    /// <summary>
    /// Translates a list of SortClauses.
    /// Used in the translation of OrderBy 
    /// </summary>
    /// <param name="orderByClause">The SqlBuilder to which the sort keys should be appended</param>
    /// <param name="sortKeys"></param>
    void AddSortKeys(SqlBuilder orderByClause, IList<DbSortClause> sortKeys)
    {
      string separator = "";
      foreach (DbSortClause sortClause in sortKeys)
      {
        orderByClause.Append(separator);
        orderByClause.Append(sortClause.Expression.Accept(this));
        Debug.Assert(sortClause.Collation != null);
        if (!String.IsNullOrEmpty(sortClause.Collation))
        {
          orderByClause.Append(" COLLATE ");
          orderByClause.Append(sortClause.Collation);
        }

        orderByClause.Append(sortClause.Ascending ? " ASC" : " DESC");

        separator = ", ";
      }
    }

    /// <summary>
    /// <see cref="CreateNewSelectStatement(SqlSelectStatement oldStatement, string inputVarName, TypeUsage inputVarType, bool finalizeOldStatement, out Symbol fromSymbol) "/>
    /// </summary>
    /// <param name="oldStatement"></param>
    /// <param name="inputVarName"></param>
    /// <param name="inputVarType"></param>
    /// <param name="fromSymbol"></param>
    /// <returns>A new select statement, with the old one as the from clause.</returns>
    SqlSelectStatement CreateNewSelectStatement(SqlSelectStatement oldStatement,
        string inputVarName, TypeUsage inputVarType, out Symbol fromSymbol)
    {
      return CreateNewSelectStatement(oldStatement, inputVarName, inputVarType, true, out fromSymbol);
    }


    /// <summary>
    /// This is called after a relational node's input has been visited, and the
    /// input's sql statement cannot be reused.  <see cref="Visit(DbProjectExpression)"/>
    ///
    /// When the input's sql statement cannot be reused, we create a new sql
    /// statement, with the old one as the from clause of the new statement.
    ///
    /// The old statement must be completed i.e. if it has an empty select list,
    /// the list of columns must be projected out.
    ///
    /// If the old statement being completed has a join symbol as its from extent,
    /// the new statement must have a clone of the join symbol as its extent.
    /// We cannot reuse the old symbol, but the new select statement must behave
    /// as though it is working over the "join" record.
    /// </summary>
    /// <param name="oldStatement"></param>
    /// <param name="inputVarName"></param>
    /// <param name="inputVarType"></param>
    /// <param name="finalizeOldStatement"></param>
    /// <param name="fromSymbol"></param>
    /// <returns>A new select statement, with the old one as the from clause.</returns>
    SqlSelectStatement CreateNewSelectStatement(SqlSelectStatement oldStatement,
        string inputVarName, TypeUsage inputVarType, bool finalizeOldStatement, out Symbol fromSymbol)
    {
      fromSymbol = null;

      // Finalize the old statement
      if (finalizeOldStatement && oldStatement.Select.IsEmpty)
      {
        List<Symbol> columns = AddDefaultColumns(oldStatement);

        // Thid could not have been called from a join node.
        Debug.Assert(oldStatement.FromExtents.Count == 1);

        // if the oldStatement has a join as its input, ...
        // clone the join symbol, so that we "reuse" the
        // join symbol.  Normally, we create a new symbol - see the next block
        // of code.
        JoinSymbol oldJoinSymbol = oldStatement.FromExtents[0] as JoinSymbol;
        if (oldJoinSymbol != null)
        {
          // Note: oldStatement.FromExtents will not do, since it might
          // just be an alias of joinSymbol, and we want an actual JoinSymbol.
          JoinSymbol newJoinSymbol = new JoinSymbol(inputVarName, inputVarType, oldJoinSymbol.ExtentList);
          // This indicates that the oldStatement is a blocking scope
          // i.e. it hides/renames extent columns
          newJoinSymbol.IsNestedJoin = true;
          newJoinSymbol.ColumnList = columns;
          newJoinSymbol.FlattenedExtentList = oldJoinSymbol.FlattenedExtentList;

          fromSymbol = newJoinSymbol;
        }
      }

      if (fromSymbol == null)
      {
        // This is just a simple extent/SqlSelectStatement,
        // and we can get the column list from the type.
        fromSymbol = new Symbol(inputVarName, inputVarType);
      }

      // Observe that the following looks like the body of Visit(ExtentExpression).
      SqlSelectStatement selectStatement = new SqlSelectStatement();
      selectStatement.From.Append("( ");
      selectStatement.From.Append(oldStatement);
      selectStatement.From.AppendLine();
      selectStatement.From.Append(") ");


      return selectStatement;
    }


    /// <summary>
    /// Before we embed a string literal in a SQL string, we should
    /// convert all ' to '', and enclose the whole string in single quotes.
    /// </summary>
    /// <param name="s"></param>
    /// <param name="isUnicode"></param>
    /// <returns>The escaped sql string.</returns>
    private string EscapeSingleQuote(string s, bool isUnicode)
    {
      return "'" + s.Replace("'", "''") + "'";
    }

    /// <summary>
    /// Returns the sql primitive/native type name. 
    /// It will include size, precision or scale depending on type information present in the 
    /// type facets
    /// </summary>
    /// <param name="type"></param>
    /// <returns></returns>
    private string GetSqlPrimitiveType(TypeUsage type)
    {
      PrimitiveType primitiveType = MetadataHelpers.GetEdmType<PrimitiveType>(type);

      string typeName = primitiveType.Name;
      bool isUnicode = true;
      bool isFixedLength = false;
      int maxLength = 0;
      string length = "max";
      bool preserveSeconds = true;
      byte decimalPrecision = 0;
      byte decimalScale = 0;

      switch (primitiveType.PrimitiveTypeKind)
      {
        case PrimitiveTypeKind.Binary:
          maxLength = MetadataHelpers.GetFacetValueOrDefault<int>(type, MetadataHelpers.MaxLengthFacetName, MetadataHelpers.BinaryMaxMaxLength);
          if (maxLength == MetadataHelpers.BinaryMaxMaxLength)
          {
            length = "max";
          }
          else
          {
            length = maxLength.ToString(CultureInfo.InvariantCulture);
          }
          isFixedLength = MetadataHelpers.GetFacetValueOrDefault<bool>(type, MetadataHelpers.FixedLengthFacetName, false);
          typeName = (isFixedLength ? "binary(" : "varbinary(") + length + ")";
          break;

        case PrimitiveTypeKind.String:
          // Question: How do we handle ntext?
          isUnicode = MetadataHelpers.GetFacetValueOrDefault<bool>(type, MetadataHelpers.UnicodeFacetName, true);
          isFixedLength = MetadataHelpers.GetFacetValueOrDefault<bool>(type, MetadataHelpers.FixedLengthFacetName, false);
          maxLength = MetadataHelpers.GetFacetValueOrDefault<int>(type, MetadataHelpers.MaxLengthFacetName, Int32.MinValue);
          if (maxLength == Int32.MinValue)
          {
            length = "max";
          }
          else
          {
            length = maxLength.ToString(CultureInfo.InvariantCulture);
          }
          if (isUnicode && !isFixedLength && maxLength > 4000)
            length = "max";
          if (!isUnicode && !isFixedLength && maxLength > 8000)
            length = "max";
          if (isFixedLength)
          {
            typeName = (isUnicode ? "nchar(" : "char(") + length + ")";
          }
          else
          {
            typeName = (isUnicode ? "nvarchar(" : "varchar(") + length + ")";
          }
          break;

        case PrimitiveTypeKind.DateTime:
          preserveSeconds = MetadataHelpers.GetFacetValueOrDefault<bool>(type, MetadataHelpers.PreserveSecondsFacetName, false);
          typeName = preserveSeconds ? "datetime" : "smalldatetime";
          break;

        case PrimitiveTypeKind.Decimal:
          decimalPrecision = MetadataHelpers.GetFacetValueOrDefault<byte>(type, MetadataHelpers.PrecisionFacetName, 18);
          Debug.Assert(decimalPrecision > 0, "decimal precision must be greater than zero");
          decimalScale = MetadataHelpers.GetFacetValueOrDefault<byte>(type, MetadataHelpers.ScaleFacetName, 0);
          Debug.Assert(decimalPrecision >= decimalScale, "decimalPrecision must be greater or equal to decimalScale");
          Debug.Assert(decimalPrecision <= 53, "decimalPrecision must be less than or equal to 53");
          typeName = typeName + "(" + decimalPrecision + "," + decimalScale + ")";
          break;

        case PrimitiveTypeKind.Int32:
          typeName = "int";
          break;

        case PrimitiveTypeKind.Int64:
          typeName = "bigint";
          break;

        case PrimitiveTypeKind.Int16:
          typeName = "smallint";
          break;

        case PrimitiveTypeKind.Byte:
          typeName = "tinyint";
          break;

        case PrimitiveTypeKind.Boolean:
          typeName = "bit";
          break;

        case PrimitiveTypeKind.Single:
          typeName = "real";
          break;

        case PrimitiveTypeKind.Double:
          typeName = "float";
          break;

        case PrimitiveTypeKind.Guid:
          typeName = "uniqueidentifier";
          break;

        default:
          throw new NotSupportedException("Unsupported EdmType: " + primitiveType.PrimitiveTypeKind);
      }

      return typeName;
    }

    /// <summary>
    /// Handles the expression represending DbLimitExpression.Limit and DbSkipExpression.Count.
    /// If it is a constant expression, it simply does to string thus avoiding casting it to the specific value
    /// (which would be done if <see cref="Visit(DbConstantExpression)"/> is called)
    /// </summary>
    /// <param name="e"></param>
    /// <returns></returns>
    private ISqlFragment HandaleCountExpression(DbExpression e)
    {
      ISqlFragment result;

      if (e.ExpressionKind == DbExpressionKind.Constant)
      {
        //For constant expression we should not cast the value, 
        // thus we don't go throught the default DbConstantExpression handling
        SqlBuilder sqlBuilder = new SqlBuilder();
        sqlBuilder.Append(((DbConstantExpression)e).Value.ToString());
        result = sqlBuilder;
      }
      else
      {
        result = e.Accept(this);
      }

      return result;
    }

    /// <summary>
    /// This is used to determine if a particular expression is an Apply operation.
    /// This is only the case when the DbExpressionKind is CrossApply or OuterApply.
    /// </summary>
    /// <param name="e"></param>
    /// <returns></returns>
    bool IsApplyExpression(DbExpression e)
    {
      return (DbExpressionKind.CrossApply == e.ExpressionKind || DbExpressionKind.OuterApply == e.ExpressionKind);
    }

    /// <summary>
    /// This is used to determine if a particular expression is a Join operation.
    /// This is true for DbCrossJoinExpression and DbJoinExpression, the
    /// latter of which may have one of several different ExpressionKinds.
    /// </summary>
    /// <param name="e"></param>
    /// <returns></returns>
    bool IsJoinExpression(DbExpression e)
    {
      return (DbExpressionKind.CrossJoin == e.ExpressionKind ||
              DbExpressionKind.FullOuterJoin == e.ExpressionKind ||
              DbExpressionKind.InnerJoin == e.ExpressionKind ||
              DbExpressionKind.LeftOuterJoin == e.ExpressionKind);
    }

    /// <summary>
    /// This is used to determine if a calling expression needs to place
    /// round brackets around the translation of the expression e.
    ///
    /// Constants, parameters and properties do not require brackets,
    /// everything else does.
    /// </summary>
    /// <param name="e"></param>
    /// <returns>true, if the expression needs brackets </returns>
    bool IsComplexExpression(DbExpression e)
    {
      switch (e.ExpressionKind)
      {
        case DbExpressionKind.Constant:
        case DbExpressionKind.ParameterReference:
        case DbExpressionKind.Property:
          return false;

        default:
          return true;
      }
    }

    /// <summary>
    /// Determine if the owner expression can add its unique sql to the input's
    /// SqlSelectStatement
    /// </summary>
    /// <param name="result">The SqlSelectStatement of the input to the relational node.</param>
    /// <param name="expressionKind">The kind of the expression node(not the input's)</param>
    /// <returns></returns>
    bool IsCompatible(SqlSelectStatement result, DbExpressionKind expressionKind)
    {
      switch (expressionKind)
      {
        case DbExpressionKind.Distinct:
          return result.Top == null
            // The projection after distinct may not project all 
            // columns used in the Order By
              && result.OrderBy.IsEmpty;

        case DbExpressionKind.Filter:
          return result.Select.IsEmpty
                  && result.Where.IsEmpty
                  && result.GroupBy.IsEmpty
                  && result.Top == null;

        case DbExpressionKind.GroupBy:
          return result.Select.IsEmpty
                  && result.GroupBy.IsEmpty
                  && result.OrderBy.IsEmpty
                  && result.Top == null;

        case DbExpressionKind.Limit:
        case DbExpressionKind.Element:
          return result.Top == null;

        case DbExpressionKind.Project:
          return result.Select.IsEmpty
                  && result.GroupBy.IsEmpty;

        case DbExpressionKind.Skip:
          return result.Select.IsEmpty
                  && result.GroupBy.IsEmpty
                  && result.OrderBy.IsEmpty
                  && !result.IsDistinct;

        case DbExpressionKind.Sort:
          return result.Select.IsEmpty
                  && result.GroupBy.IsEmpty
                  && result.OrderBy.IsEmpty;

        default:
          Debug.Assert(false);
          throw new InvalidOperationException();
      }

    }

    /// <summary>
    /// We use the normal box quotes for SQL server.  We do not deal with ANSI quotes
    /// i.e. double quotes.
    /// </summary>
    /// <param name="name"></param>
    /// <returns></returns>
    internal static string QuoteIdentifier(string name)
    {
      Debug.Assert(!String.IsNullOrEmpty(name));
      // We assume that the names are not quoted to begin with.
      return "[" + name.Replace("]", "]]") + "]";
    }

    /// <summary>
    /// Simply calls <see cref="VisitExpressionEnsureSqlStatement(DbExpression, bool)"/>
    /// with addDefaultColumns set to true
    /// </summary>
    /// <param name="e"></param>
    /// <returns></returns>
    SqlSelectStatement VisitExpressionEnsureSqlStatement(DbExpression e)
    {
      return VisitExpressionEnsureSqlStatement(e, true);
    }

    /// <summary>
    /// This is called from <see cref="GenerateSql(DbQueryCommandTree)"/> and nodes which require a
    /// select statement as an argument e.g. <see cref="Visit(DbIsEmptyExpression)"/>,
    /// <see cref="Visit(DbUnionAllExpression)"/>.
    ///
    /// SqlGenerator needs its child to have a proper alias if the child is
    /// just an extent or a join.
    ///
    /// The normal relational nodes result in complete valid SQL statements.
    /// For the rest, we need to treat them as there was a dummy
    /// <code>
    /// -- originally {expression}
    /// -- change that to
    /// SELECT *
    /// FROM {expression} as c
    /// </code>
    /// 
    /// DbLimitExpression needs to start the statement but not add the default columns
    /// </summary>
    /// <param name="e"></param>
    /// <param name="addDefaultColumns"></param>
    /// <returns></returns>
    SqlSelectStatement VisitExpressionEnsureSqlStatement(DbExpression e, bool addDefaultColumns)
    {
      Debug.Assert(MetadataHelpers.IsCollectionType(e.ResultType));

      SqlSelectStatement result;
      switch (e.ExpressionKind)
      {
        case DbExpressionKind.Project:
        case DbExpressionKind.Filter:
        case DbExpressionKind.GroupBy:
        case DbExpressionKind.Sort:
          result = e.Accept(this) as SqlSelectStatement;
          break;

        default:
          Symbol fromSymbol;
          string inputVarName = "c";  // any name will do - this is my random choice.
          symbolTable.EnterScope();

          TypeUsage type = null;
          switch (e.ExpressionKind)
          {
            case DbExpressionKind.Scan:
            case DbExpressionKind.CrossJoin:
            case DbExpressionKind.FullOuterJoin:
            case DbExpressionKind.InnerJoin:
            case DbExpressionKind.LeftOuterJoin:
            case DbExpressionKind.CrossApply:
            case DbExpressionKind.OuterApply:
              type = MetadataHelpers.GetElementTypeUsage(e.ResultType);
              break;

            default:
              Debug.Assert(MetadataHelpers.IsCollectionType(e.ResultType));
              type = MetadataHelpers.GetEdmType<CollectionType>(e.ResultType).TypeUsage;
              break;
          }

          result = VisitInputExpression(e, inputVarName, type, out fromSymbol);
          AddFromSymbol(result, inputVarName, fromSymbol);
          symbolTable.ExitScope();
          break;
      }

      if (addDefaultColumns && result.Select.IsEmpty)
      {
        AddDefaultColumns(result);
      }

      return result;
    }

    /// <summary>
    /// This method is called by <see cref="Visit(DbFilterExpression)"/> and
    /// <see cref="Visit(DbQuantifierExpression)"/>
    ///
    /// </summary>
    /// <param name="input"></param>
    /// <param name="predicate"></param>
    /// <param name="negatePredicate">This is passed from <see cref="Visit(DbQuantifierExpression)"/>
    /// in the All(...) case.</param>
    /// <returns></returns>
    SqlSelectStatement VisitFilterExpression(DbExpressionBinding input, DbExpression predicate, bool negatePredicate)
    {
      Symbol fromSymbol;
      SqlSelectStatement result = VisitInputExpression(input.Expression,
          input.VariableName, input.VariableType, out fromSymbol);

      // Filter is compatible with OrderBy
      // but not with Project, another Filter or GroupBy
      if (!IsCompatible(result, DbExpressionKind.Filter))
      {
        result = CreateNewSelectStatement(result, input.VariableName, input.VariableType, out fromSymbol);
      }

      selectStatementStack.Push(result);
      symbolTable.EnterScope();

      AddFromSymbol(result, input.VariableName, fromSymbol);

      if (negatePredicate)
      {
        result.Where.Append("NOT (");
      }
      result.Where.Append(predicate.Accept(this));
      if (negatePredicate)
      {
        result.Where.Append(")");
      }

      symbolTable.ExitScope();
      selectStatementStack.Pop();

      return result;
    }

    /// <summary>
    /// If the sql fragment for an input expression is not a SqlSelect statement
    /// or other acceptable form (e.g. an extent as a SqlBuilder), we need
    /// to wrap it in a form acceptable in a FROM clause.  These are
    /// primarily the
    /// <list type="bullet">
    /// <item>The set operation expressions - union all, intersect, except</item>
    /// <item>TVFs, which are conceptually similar to tables</item>
    /// </list>
    /// </summary>
    /// <param name="result"></param>
    /// <param name="sqlFragment"></param>
    /// <param name="expressionKind"></param>
    void WrapNonQueryExtent(SqlSelectStatement result, ISqlFragment sqlFragment, DbExpressionKind expressionKind)
    {
      switch (expressionKind)
      {
        case DbExpressionKind.Function:
          // TVF
          result.From.Append(sqlFragment);
          break;

        default:
          result.From.Append(" (");
          result.From.Append(sqlFragment);
          result.From.Append(")");
          break;
      }
    }

    /// <summary>
    /// Is this a builtin function (ie) does it have the builtinAttribute specified?
    /// </summary>
    /// <param name="function"></param>
    /// <returns></returns>
    private static bool IsBuiltinFunction(EdmFunction function)
    {
      return MetadataHelpers.TryGetValueForMetadataProperty<bool>(function, "BuiltInAttribute");
    }

    /// <summary>
    ///
    /// </summary>
    /// <param name="function"></param>
    /// <param name="result"></param>
    void WriteFunctionName(SqlBuilder result, EdmFunction function)
    {
      string storeFunctionName = MetadataHelpers.TryGetValueForMetadataProperty<string>(function, "StoreFunctionNameAttribute");

      if (string.IsNullOrEmpty(storeFunctionName))
      {
        storeFunctionName = function.Name;
      }

      // If the function is a builtin (ie) the BuiltIn attribute has been
      // specified, then, the function name should not be quoted; additionally,
      // no namespace should be used.
      if (IsBuiltinFunction(function))
      {
        if (function.NamespaceName == "Edm")
        {
          switch (storeFunctionName.ToUpperInvariant())
          {
            default:
              result.Append(storeFunctionName);
              break;
          }

        }
        else
        {
          result.Append(storeFunctionName);
        }

      }
      else
      {
        // Should we actually support this?
        result.Append(QuoteIdentifier((string)function.MetadataProperties["Schema"].Value ?? "dbo"));
        result.Append(".");
        result.Append(QuoteIdentifier(storeFunctionName));
      }
    }

    static string ByteArrayToBinaryString(Byte[] binaryArray)
    {
      StringBuilder sb = new StringBuilder(binaryArray.Length * 2);
      for (int i = 0; i < binaryArray.Length; i++)
      {
        sb.Append(hexDigits[(binaryArray[i] & 0xF0) >> 4]).Append(hexDigits[binaryArray[i] & 0x0F]);
      }
      return sb.ToString();
    }

    /// <summary>
    /// Helper method for the Group By visitor
    /// Returns true if at least one of the aggregates in the given list
    /// has an argument that is not a <see cref="DbPropertyExpression"/> 
    /// over <see cref="DbVariableReferenceExpression"/>
    /// </summary>
    /// <param name="aggregates"></param>
    /// <returns></returns>
    static bool NeedsInnerQuery(IList<DbAggregate> aggregates)
    {
      foreach (DbAggregate aggregate in aggregates)
      {
        Debug.Assert(aggregate.Arguments.Count == 1);
        if (!IsPropertyOverVarRef(aggregate.Arguments[0]))
        {
          return true;
        }
      }
      return false;
    }

    /// <summary>
    /// Determines whether the given expression is a <see cref="DbPropertyExpression"/> 
    /// over <see cref="DbVariableReferenceExpression"/>
    /// </summary>
    /// <param name="expression"></param>
    /// <returns></returns>
    static bool IsPropertyOverVarRef(DbExpression expression)
    {
      DbPropertyExpression propertyExpression = expression as DbPropertyExpression;
      if (propertyExpression == null)
      {
        return false;
      }
      DbVariableReferenceExpression varRefExpression = propertyExpression.Instance as DbVariableReferenceExpression;
      if (varRefExpression == null)
      {
        return false;
      }
      return true;
    }

    #endregion
  }

}