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ADO.NET 2.0 SQLite Data Provider<br>
Version 1.0.12 - Aug 2, 2005<br>
Interop using SQLite 3.22<br>
Written by Robert Simpson (<a href="mailto:firstname.lastname@example.org">email@example.com</a>)<br>
Released to the public domain, use at your own risk!<br>
This provider was written and tested using the Visual Studio 2005 Beta 2
The latest version can be downloaded <a href="http://sourceforge.net/projects/sqlite-dotnet2">
DbProviderFactory support, just add the XML below at the machine.config and/or
Full support for ATTACH'ed databases. Exposed as <i>Catalogs</i>
in the schema. When cloning a connection, all attached databases are
automatically re-attached to the new connection.
DbConnection.GetSchema(...) support includes the <i>MetaDataCollections</i>, <i>DataSourceInformation</i>,
<i>Columns</i>, <i>Tables</i>, <i>Views</i>, <i>Catalogs</i> and <i>Indexes</i>
Enhanced DbDataReader.GetSchemaTable() functionality returns catalog, namespace
and detailed schema information even for complex queries.
Named and unnamed parameters.
Full UTF-8 and UTF-16 support.
Multiple simultaneous DataReaders (one DataReader per Command however).
Full support for user-defined scalar and aggregate functions, encapsulated into
an easy-to-use base class in which only a couple of overrides are necessary to
implement new SQL functions.
Full support for user-defined collating sequences, every bit as simple to
implement as user-defined functions and uses the same base class.</li></ul>
<strong>DbFactory Support (Non-Compact Framework)</strong></h2>
In order to use the SQLiteFactory and have the SQLite data provider enumerated
in the DbProviderFactories methods, you must add the following segment into
either your application's app.config or the system's machine.config located in
the %SystemRoot%\Microsoft.Net\Framework\v2.xxxx\Config folder:<br>
<add name="SQLite Data Provider" invariant="System.Data.SQLite" support="3F" description=".Net Framework Data Provider for SQLite" type="System.Data.SQLite.SQLiteFactory, System.Data.SQLite" />
Compiling for the Compact Framework</h3>
Just change the target platform from Win32 to Compact Framework and
recompile. <STRONG>The Compact Framework has no support for enumerating
attributes in an assembly, therefore all user-defined collating sequences and
functions must be explicitly registered.</STRONG> See the <STRONG>testce</STRONG>
sample application for an example of how to explicitly register user-defined
collating sequences and functions.</p>
<b><A name="redist"></A>Distributing The SQLite Engine and ADO.NET Assembly</b></h2>
<P>For Win32 platforms, only the <STRONG>System.Data.SQLite.DLL</STRONG> file in
the <STRONG>bin</STRONG> folder should be distributed with your
application(s). This DLL contains both the managed wrapper and the native
<P>For Compact Framework platforms, your application should reference the <STRONG>System.Data.SQLite.DLL</STRONG>
file in the <STRONG>bin\CompactFramework</STRONG> folder. The <STRONG>System.Data.SQLite.DLL</STRONG>
and <STRONG>SQLite.Interop.DLL</STRONG> files from the <STRONG>bin\CompactFramework</STRONG>
folder must be distributed with your application(s). They contain the
managed wrapper and the native SQLite3 codebase respectively. The Compact
Framework does not currently support managed C++, thus the reason for two
<H2><B>Development Notes Regarding the SQLite 3 Source Code</B></H2>
Steps for merging the sqlite3 core codebase:</p>
<strong>This section is obsolete, but remains for historical purposes. The
1.0.11+ versions of the ADO.NET 2.0 SQLite provider make significant changes to
the core sqlite3 codebase in order to support C++ /clr compiling.
Specifically, all the implicit casts throughout the core codebase must be
modified. There are several hundred of these casts and they must be fixed
up every time a new sqlite version is released.</strong></p>
<FONT color="silver">Download the latest sqlite3 source from </FONT><a href="http://www.sqlite.org/download.html">
<FONT color="silver">http://www.sqlite.org/download.html</FONT></a><FONT color="silver">
<FONT color="silver">Extract the source code to the <b>SQLite.Interop\src</b> directory
of this project </FONT>
<FONT color="silver">Open the <b>src\select.c</b> file. </FONT>
<FONT color="silver">Add <b>#include "../interop.h" </b>to the top of the file
where the other include's are. </FONT>
<FONT color="silver">Scroll down the <b>select.c</b> file to around line <b>748</b>.
Change the name of the function <b>static void generateColumnNames </b>to <b>static
void _generateColumnNames</b> (<i>note the underscore in front of the name</i>).
<FONT color="silver">Compile it. </FONT>
<b>1.0.12 - August 2, 2005</b><br>
Full support for the Compact Framework. Each build (Debug/Release) now
has a platform, either Win32 or Compact Framework. The correct
projects are built accordingly. See the <a href="#redist">Distributing
SQLite</a> section for information on what files need to be distributed for
each platform. </li>
<b>1.0.11 - August 1, 2005</b><br>
<strong>For everything except the Compact Framework, System.Data.SQLite.DLL is
now the <em>only</em> DLL required to use this provider!</strong> The
assembly is now a multi-module assembly, containing both the native SQLite3
codebase and the C# classes built on top of it. The Compact Framework
version (when completed) will not be able to support this feature, so backwards
compatibility with the Compact Framework has been preserved for the future.
Fixed a bug in SQLiteCommand.ExecuteScalar() that caused it to stop executing
commands once it obtained the first column of the first row-returning
resultset. Any remaining statements after the row-returning statement was
<b>1.0.10 - June 10, 2005</b><br>
Fixed a bug in the SQLite3.cs Prepare() function that created a statement even
when the SQLite engine returned a NULL pointer. Typically this occurs when
multiple statements are processed and there are trailing comments at the end of
Fixed a bug in SQLiteStatement.cs that retrieved parameter names for a
parameterized query. SQLite's parameters are 1-based, and the function
was starting at 0. This was fine when all parameters were unnamed, but
for named parameters it caused the parameters to be out of whack.</li>
<b>1.0.09a - May 25, 2005</b><br>
Fixed a broken helpfile and corrected some obsolete help remarks in
SQLiteFunction.cs<li>Added a version resource to the SQLite.Interop.DLL. </li></ul>
<b>1.0.09 - May 24, 2005</b><br>
Code merge with the latest 3.21 version of SQLite.
Removed obsolete methods and properties for Whidbey Beta 2</li></ul>
<b>1.0.08 Refresh - Mar 24, 2005<br>
Code merge with the latest 3.20 version of SQLite.
Recompiled the help file to fix a build error in it.</li>
<b>1.0.08 - Mar 11, 2005<br>
Added additional #if statements to support the old beta 1 edition of VS2005.
Code merged the SQLite 3.14 source.</li>
<b>1.0.07 - Mar 5, 2005</b><br>
Made more optimizations to frequently-called functions, resulting in
significant performance gains in all tests.
Recompiled the binaries using the latest VS2005 February CTP, resulting in yet
more significant speed gains. The 100k insert test used to take 3.5
seconds and the insertwithidentity took almost 8 seconds. With the above
two changes, those tests are now executing in 1.9 and 4.9 seconds respectively.</li></ul>
<b>1.0.06 - Mar 1, 2005<br>
Speed-ups to SQLiteDataReader. It was interop'ing unnecessarily every
time it tried to fetch a field due to a logic error.
Changed/Added some code to SQLiteConvert's internal DbType, Type and
Fixed the SQLiteDataReader to obey the flags set in the optional
CommandBehavior flag from SQLiteCommand.ExecuteReader().
Changed the default page size to 1024 to reflect the defaults of SQLite.
Ignores the "Page Size" connection string option for memory databases, as tests
revealed that changing it resulted in memory corruption errors.
Performance enhancements to the SQLiteCommand and SQLiteStatement classes which
reduced the 100,000 row insert execution time as well as the various Function
execution times significantly.</li>
1.0.05 - Feb 25, 2005</b>
Fixed the SQLite3 C# class step/reset functions to accomodate schema changes
that invalidate a prepared statement. Statements are recompiled
Moved all native DLL declarations to an UnsafeNativeMethods class.
Split several classes into their own modules for readability.
Renamed many internal variables, reviewed access to variables marked as
internal and altered their protection levels accordingly.
Due to the presence of the altered sqlite3 codebase and so many added interop
functions, I decided to rename the sqlite3 C project and the DLL to
SQLite.Interop.DLL. This is the same core sqlite3 codebase but designed
specifically for this ADO.NET provider. This eliminates any possibility
of someone dropping another build of sqlite3.dll into the system and rendering
the provider inoperable. In the future if the folks at sqlite.org finally
introduce a method of retrieving column usage for an arbitrary prepared
statement, I'll retool this library to be a lightweight function call wrapper
around the core binary distribution.
Added [SuppressUnmanagedCodeSecurity] attribute to the UnsafeNativeMethods
class which brings VS2005 November CTP execution speeds inline with the
Added a <b>bin</b>
directory to the project root where pre-compiled binaries can be found.
Added a <b>doc</b>
directory where preliminary documentation on the class library can be found.
Documented a lot more of the classes internally.</li>
1.0.04 - Feb 24, 2005</b>
Removed the SQLiteContext class and revamped the way UserFunctions work to
simplify the imlementation.
Fixed a counting bug in the TestCases class, specifically in the function tests
where I wasn't resetting the counter and it was consequently reporting
intrinsic and raw select calls as being much much faster than they actually
were. The numbers are now much closer to what I expected for performance,
with .NET user-functions still being the slowest, but only by a small margin.
Small performance tweaks to SQLiteDataReader.
Added PageSize to the SQLiteConnectionStringBuilder and subsequently to the
Added a PRAGMA encoding=XXX execution statement to the SQLiteConnection after
opening a connection.</li>
<b>1.0.03 - Feb 23, 2005</b>
Fixed up SQLiteCommandBuilder to correct implementation errors, which resulted
in an enormous performance boost in the InsertMany test. 10,000 row
insert that executed in 1500ms now executes in 500ms.
Fixed several errors in the SQLite3_UTF16 class. ToString() was working
incorrectly and the Open() method failed to register user defined functions and
Fixed a bug in SQLiteCommand.ClearCommands() whereby only the first statement
was being properly cleaned up.
Fixed a bug in SQLiteDataReader whereby calling NextResult() would not properly
reset the previously-executed command in the sequence.
Added an InsertManyWithIdentityFetch test, which appends a select clause to
populate the ID of the last inserted row into the InsertCommand, demonstrating
ADO.NET's ability to auto-fetch identity columns on insert.</li>
<b>1.0.02 - Feb 21, 2005</b></p>
Tweaks to the xxx_interop functions that return char *'s, so they also return
the length. Saves an interop call to get the UTF-8 string length during
conversion to a .NET string.
Reworked the whole interop.c thing into interop.h and reduced the code required
to merge the main sqlite3 codebase.
Added support for user-defined collations.</li>