System.Data.SQLite

      </table>
    </div>
    <div id="mainSection">
    <div id="mainBody">
    <h1 class="heading">Version History</h1>
    <p><b>1.0.111.0 - July XX, 2019 <font color="red">(release scheduled)</font></b></p>
    <ul>
      <li>Updated to <a href="https://www.sqlite.org/releaselog/3_28_0.html">SQLite 3.28.0</a>.</li>
      <li>Add No_SQLiteLog environment variable.</li>
    </ul>
    <p><b>1.0.110.0 - March 4, 2019</b></p>
    <ul>
      <li>Updated to <a href="https://www.sqlite.org/releaselog/3_27_2.html">SQLite 3.27.2</a>.</li>
      <li>Add HidePassword connection flag to remove the password from the connection string once the database is opened. Pursuant to <a href="https://system.data.sqlite.org/index.html/info/23d8d6171e">[23d8d6171e]</a>.</li>
      <li>Add experimental StrictConformance connection flag to force strict compliance to the ADO.NET standard. Pursuant to <a href="https://system.data.sqlite.org/index.html/info/e36e05e299">[e36e05e299]</a>.</li>

<?xml version="1.0" encoding="utf-8"?>
<!--
 *
 * sqlite3.props -
 *
 * Written by Joe Mistachkin.
 * Released to the public domain, use at your own risk!
 *
-->
<Project DefaultTargets="Build" xmlns="http://schemas.microsoft.com/developer/msbuild/2003" ToolsVersion="4.0">
  <PropertyGroup Label="UserMacros">
    <SQLITE_MANIFEST_VERSION>3.28.0.0</SQLITE_MANIFEST_VERSION>
    <SQLITE_RC_VERSION>3,28,0,0</SQLITE_RC_VERSION>
    <SQLITE_COMMON_DEFINES>_CRT_SECURE_NO_DEPRECATE;_CRT_SECURE_NO_WARNINGS;_CRT_NONSTDC_NO_DEPRECATE;_CRT_NONSTDC_NO_WARNINGS;SQLITE_THREADSAFE=1;SQLITE_USE_URI=1;SQLITE_ENABLE_COLUMN_METADATA=1;SQLITE_ENABLE_STAT4=1;SQLITE_ENABLE_FTS3=1;SQLITE_ENABLE_LOAD_EXTENSION=1;SQLITE_ENABLE_RTREE=1;SQLITE_SOUNDEX=1;SQLITE_ENABLE_MEMORY_MANAGEMENT=1;SQLITE_ENABLE_API_ARMOR=1;SQLITE_ENABLE_DBSTAT_VTAB=1;SQLITE_ENABLE_STMTVTAB=1</SQLITE_COMMON_DEFINES>
    <SQLITE_EXTRA_DEFINES>SQLITE_PLACEHOLDER=1;SQLITE_HAS_CODEC=1</SQLITE_EXTRA_DEFINES>
    <SQLITE_WINCE_200X_DEFINES>SQLITE_OMIT_WAL=1</SQLITE_WINCE_200X_DEFINES>
    <SQLITE_WINCE_2013_DEFINES>HAVE_ERRNO_H=1;SQLITE_MSVC_LOCALTIME_API=1</SQLITE_WINCE_2013_DEFINES>
    <SQLITE_DEBUG_DEFINES>SQLITE_DEBUG=1;SQLITE_MEMDEBUG=1;SQLITE_ENABLE_EXPENSIVE_ASSERT=1</SQLITE_DEBUG_DEFINES>
    <SQLITE_RELEASE_DEFINES>SQLITE_WIN32_MALLOC=1</SQLITE_RELEASE_DEFINES>
    <SQLITE_DISABLE_WARNINGS>4055;4100;4127;4146;4210;4232;4244;4245;4267;4306;4389;4701;4703;4706</SQLITE_DISABLE_WARNINGS>

<VisualStudioPropertySheet
	ProjectType="Visual C++"
	Version="8.00"
	Name="sqlite3"
	>
	<UserMacro
		Name="SQLITE_MANIFEST_VERSION"
		Value="3.28.0.0"
		PerformEnvironmentSet="true"
	/>
	<UserMacro
		Name="SQLITE_RC_VERSION"
		Value="3,28,0,0"
		PerformEnvironmentSet="true"
	/>
	<UserMacro
		Name="SQLITE_COMMON_DEFINES"
		Value="_CRT_SECURE_NO_DEPRECATE;_CRT_SECURE_NO_WARNINGS;_CRT_NONSTDC_NO_DEPRECATE;_CRT_NONSTDC_NO_WARNINGS;SQLITE_THREADSAFE=1;SQLITE_USE_URI=1;SQLITE_ENABLE_COLUMN_METADATA=1;SQLITE_ENABLE_STAT4=1;SQLITE_ENABLE_FTS3=1;SQLITE_ENABLE_LOAD_EXTENSION=1;SQLITE_ENABLE_RTREE=1;SQLITE_SOUNDEX=1;SQLITE_ENABLE_MEMORY_MANAGEMENT=1;SQLITE_ENABLE_API_ARMOR=1;SQLITE_ENABLE_DBSTAT_VTAB=1;SQLITE_ENABLE_STMTVTAB=1"
		PerformEnvironmentSet="true"
	/>

/******************************************************************************
** This file is an amalgamation of many separate C source files from SQLite
** version 3.28.0.  By combining all the individual C code files into this
** single large file, the entire code can be compiled as a single translation
** unit.  This allows many compilers to do optimizations that would not be
** possible if the files were compiled separately.  Performance improvements
** of 5% or more are commonly seen when SQLite is compiled as a single
** translation unit.
**
** This file is all you need to compile SQLite.  To use SQLite in other

** been edited in any way since it was last checked in, then the last
** four hexadecimal digits of the hash may be modified.
**
** See also: [sqlite3_libversion()],
** [sqlite3_libversion_number()], [sqlite3_sourceid()],
** [sqlite_version()] and [sqlite_source_id()].
*/
#define SQLITE_VERSION        "3.28.0"
#define SQLITE_VERSION_NUMBER 3028000
#define SQLITE_SOURCE_ID      "2019-04-16 19:49:53 884b4b7e502b4e991677b53971277adfaf0a04a284f8e483e2553d0f83156b50"

/*
** CAPI3REF: Run-Time Library Version Numbers
** KEYWORDS: sqlite3_version sqlite3_sourceid
**
** These interfaces provide the same information as the [SQLITE_VERSION],
** [SQLITE_VERSION_NUMBER], and [SQLITE_SOURCE_ID] C preprocessor macros

**
** See also: SQL functions [sqlite_compileoption_used()] and
** [sqlite_compileoption_get()] and the [compile_options pragma].
*/
#ifndef SQLITE_OMIT_COMPILEOPTION_DIAGS
SQLITE_API int sqlite3_compileoption_used(const char *zOptName);
SQLITE_API const char *sqlite3_compileoption_get(int N);
#else
# define sqlite3_compileoption_used(X) 0
# define sqlite3_compileoption_get(X)  ((void*)0)
#endif

/*
** CAPI3REF: Test To See If The Library Is Threadsafe
**
** ^The sqlite3_threadsafe() function returns zero if and only if
** SQLite was compiled with mutexing code omitted due to the

** The second parameter is a pointer to an integer into which
** is written 0 or 1 to indicate whether triggers are disabled or enabled
** following this call.  The second parameter may be a NULL pointer, in
** which case the trigger setting is not reported back. </dd>
**
** [[SQLITE_DBCONFIG_ENABLE_FTS3_TOKENIZER]]
** <dt>SQLITE_DBCONFIG_ENABLE_FTS3_TOKENIZER</dt>
** <dd> ^This option is used to enable or disable the
** [fts3_tokenizer()] function which is part of the
** [FTS3] full-text search engine extension.
** There should be two additional arguments.
** The first argument is an integer which is 0 to disable fts3_tokenizer() or
** positive to enable fts3_tokenizer() or negative to leave the setting
** unchanged.
** The second parameter is a pointer to an integer into which
** is written 0 or 1 to indicate whether fts3_tokenizer is disabled or enabled

** features include but are not limited to the following:
** <ul>
** <li> The [PRAGMA writable_schema=ON] statement.
** <li> Writes to the [sqlite_dbpage] virtual table.
** <li> Direct writes to [shadow tables].
** </ul>
** </dd>
**
** [[SQLITE_DBCONFIG_WRITABLE_SCHEMA]] <dt>SQLITE_DBCONFIG_WRITABLE_SCHEMA</dt>
** <dd>The SQLITE_DBCONFIG_WRITABLE_SCHEMA option activates or deactivates the
** "writable_schema" flag. This has the same effect and is logically equivalent
** to setting [PRAGMA writable_schema=ON] or [PRAGMA writable_schema=OFF].
** The first argument to this setting is an integer which is 0 to disable 
** the writable_schema, positive to enable writable_schema, or negative to
** leave the setting unchanged. The second parameter is a pointer to an
** integer into which is written 0 or 1 to indicate whether the writable_schema
** is enabled or disabled following this call.
** </dd>
** </dl>
*/
#define SQLITE_DBCONFIG_MAINDBNAME            1000 /* const char* */
#define SQLITE_DBCONFIG_LOOKASIDE             1001 /* void* int int */
#define SQLITE_DBCONFIG_ENABLE_FKEY           1002 /* int int* */
#define SQLITE_DBCONFIG_ENABLE_TRIGGER        1003 /* int int* */
#define SQLITE_DBCONFIG_ENABLE_FTS3_TOKENIZER 1004 /* int int* */
#define SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION 1005 /* int int* */
#define SQLITE_DBCONFIG_NO_CKPT_ON_CLOSE      1006 /* int int* */
#define SQLITE_DBCONFIG_ENABLE_QPSG           1007 /* int int* */
#define SQLITE_DBCONFIG_TRIGGER_EQP           1008 /* int int* */
#define SQLITE_DBCONFIG_RESET_DATABASE        1009 /* int int* */
#define SQLITE_DBCONFIG_DEFENSIVE             1010 /* int int* */
#define SQLITE_DBCONFIG_WRITABLE_SCHEMA       1011 /* int int* */
#define SQLITE_DBCONFIG_MAX                   1011 /* Largest DBCONFIG */

/*
** CAPI3REF: Enable Or Disable Extended Result Codes
** METHOD: sqlite3
**
** ^The sqlite3_extended_result_codes() routine enables or disables the
** [extended result codes] feature of SQLite. ^The extended result

** ^The sqlite3_stmt_readonly() interface returns true for [BEGIN] since
** [BEGIN] merely sets internal flags, but the [BEGIN|BEGIN IMMEDIATE] and
** [BEGIN|BEGIN EXCLUSIVE] commands do touch the database and so
** sqlite3_stmt_readonly() returns false for those commands.
*/
SQLITE_API int sqlite3_stmt_readonly(sqlite3_stmt *pStmt);

/*
** CAPI3REF: Query The EXPLAIN Setting For A Prepared Statement
** METHOD: sqlite3_stmt
**
** ^The sqlite3_stmt_isexplain(S) interface returns 1 if the
** prepared statement S is an EXPLAIN statement, or 2 if the
** statement S is an EXPLAIN QUERY PLAN.
** ^The sqlite3_stmt_isexplain(S) interface returns 0 if S is
** an ordinary statement or a NULL pointer.
*/
SQLITE_API int sqlite3_stmt_isexplain(sqlite3_stmt *pStmt);

/*
** CAPI3REF: Determine If A Prepared Statement Has Been Reset
** METHOD: sqlite3_stmt
**
** ^The sqlite3_stmt_busy(S) interface returns true (non-zero) if the
** [prepared statement] S has been stepped at least once using 
** [sqlite3_step(S)] but has neither run to completion (returned

** the value of the fourth parameter then the resulting string value will
** contain embedded NULs.  The result of expressions involving strings
** with embedded NULs is undefined.
**
** ^The fifth argument to the BLOB and string binding interfaces
** is a destructor used to dispose of the BLOB or
** string after SQLite has finished with it.  ^The destructor is called
** to dispose of the BLOB or string even if the call to the bind API fails,
** except the destructor is not called if the third parameter is a NULL
** pointer or the fourth parameter is negative.
** ^If the fifth argument is
** the special value [SQLITE_STATIC], then SQLite assumes that the
** information is in static, unmanaged space and does not need to be freed.
** ^If the fifth argument has the value [SQLITE_TRANSIENT], then
** SQLite makes its own private copy of the data immediately, before
** the sqlite3_bind_*() routine returns.
**

** <tr><td><b>sqlite3_value_type</b><td>&rarr;<td>Default
** datatype of the value
** <tr><td><b>sqlite3_value_numeric_type&nbsp;&nbsp;</b>
** <td>&rarr;&nbsp;&nbsp;<td>Best numeric datatype of the value
** <tr><td><b>sqlite3_value_nochange&nbsp;&nbsp;</b>
** <td>&rarr;&nbsp;&nbsp;<td>True if the column is unchanged in an UPDATE
** against a virtual table.
** <tr><td><b>sqlite3_value_frombind&nbsp;&nbsp;</b>
** <td>&rarr;&nbsp;&nbsp;<td>True if value originated from a [bound parameter]
** </table></blockquote>
**
** <b>Details:</b>
**
** These routines extract type, size, and content information from
** [protected sqlite3_value] objects.  Protected sqlite3_value objects
** are used to pass parameter information into implementation of

** the value for that column returned without setting a result (probably
** because it queried [sqlite3_vtab_nochange()] and found that the column
** was unchanging).  ^Within an [xUpdate] method, any value for which
** sqlite3_value_nochange(X) is true will in all other respects appear
** to be a NULL value.  If sqlite3_value_nochange(X) is invoked anywhere other
** than within an [xUpdate] method call for an UPDATE statement, then
** the return value is arbitrary and meaningless.
**
** ^The sqlite3_value_frombind(X) interface returns non-zero if the
** value X originated from one of the [sqlite3_bind_int|sqlite3_bind()]
** interfaces.  ^If X comes from an SQL literal value, or a table column,
** and expression, then sqlite3_value_frombind(X) returns zero.
**
** Please pay particular attention to the fact that the pointer returned
** from [sqlite3_value_blob()], [sqlite3_value_text()], or
** [sqlite3_value_text16()] can be invalidated by a subsequent call to
** [sqlite3_value_bytes()], [sqlite3_value_bytes16()], [sqlite3_value_text()],
** or [sqlite3_value_text16()].
**

SQLITE_API const void *sqlite3_value_text16le(sqlite3_value*);
SQLITE_API const void *sqlite3_value_text16be(sqlite3_value*);
SQLITE_API int sqlite3_value_bytes(sqlite3_value*);
SQLITE_API int sqlite3_value_bytes16(sqlite3_value*);
SQLITE_API int sqlite3_value_type(sqlite3_value*);
SQLITE_API int sqlite3_value_numeric_type(sqlite3_value*);
SQLITE_API int sqlite3_value_nochange(sqlite3_value*);
SQLITE_API int sqlite3_value_frombind(sqlite3_value*);

/*
** CAPI3REF: Finding The Subtype Of SQL Values
** METHOD: sqlite3_value
**
** The sqlite3_value_subtype(V) function returns the subtype for
** an [application-defined SQL function] argument V.  The subtype

** CAPI3REF: Return The Filename For A Database Connection
** METHOD: sqlite3
**
** ^The sqlite3_db_filename(D,N) interface returns a pointer to a filename
** associated with database N of connection D.  ^The main database file
** has the name "main".  If there is no attached database N on the database
** connection D, or if database N is a temporary or in-memory database, then
** this function will return either a NULL pointer or an empty string.
**
** ^The filename returned by this function is the output of the
** xFullPathname method of the [VFS].  ^In other words, the filename
** will be an absolute pathname, even if the filename used
** to open the database originally was a URI or relative pathname.
*/
SQLITE_API const char *sqlite3_db_filename(sqlite3 *db, const char *zDbName);

** CAPI3REF: Rebase a changeset
** EXPERIMENTAL
**
** Argument pIn must point to a buffer containing a changeset nIn bytes
** in size. This function allocates and populates a buffer with a copy
** of the changeset rebased rebased according to the configuration of the
** rebaser object passed as the first argument. If successful, (*ppOut)
** is set to point to the new buffer containing the rebased changeset and 
** (*pnOut) to its size in bytes and SQLITE_OK returned. It is the
** responsibility of the caller to eventually free the new buffer using
** sqlite3_free(). Otherwise, if an error occurs, (*ppOut) and (*pnOut)
** are set to zero and an SQLite error code returned.
*/
SQLITE_API int sqlite3rebaser_rebase(
  sqlite3_rebaser*,

**
**
** xSetAuxdata(pFts5, pAux, xDelete)
**
**   Save the pointer passed as the second argument as the extension functions 
**   "auxiliary data". The pointer may then be retrieved by the current or any
**   future invocation of the same fts5 extension function made as part of
**   the same MATCH query using the xGetAuxdata() API.
**
**   Each extension function is allocated a single auxiliary data slot for
**   each FTS query (MATCH expression). If the extension function is invoked 
**   more than once for a single FTS query, then all invocations share a 
**   single auxiliary data context.
**
**   If there is already an auxiliary data pointer when this function is
**   invoked, then it is replaced by the new pointer. If an xDelete callback
**   was specified along with the original pointer, it is invoked at this
**   point.
**
**   The xDelete callback, if one is specified, is also invoked on the
**   auxiliary data pointer after the FTS5 query has finished.
**
**   If an error (e.g. an OOM condition) occurs within this function,
**   the auxiliary data is set to NULL and an error code returned. If the
**   xDelete parameter was not NULL, it is invoked on the auxiliary data
**   pointer before returning.
**
**
** xGetAuxdata(pFts5, bClear)
**

** the hash table.
*/
struct Hash {
  unsigned int htsize;      /* Number of buckets in the hash table */
  unsigned int count;       /* Number of entries in this table */
  HashElem *first;          /* The first element of the array */
  struct _ht {              /* the hash table */
    unsigned int count;        /* Number of entries with this hash */
    HashElem *chain;           /* Pointer to first entry with this hash */
  } *ht;
};

/* Each element in the hash table is an instance of the following 
** structure.  All elements are stored on a single doubly-linked list.
**

#define TK_WITH                            81
#define TK_CURRENT                         82
#define TK_FOLLOWING                       83
#define TK_PARTITION                       84
#define TK_PRECEDING                       85
#define TK_RANGE                           86
#define TK_UNBOUNDED                       87
#define TK_EXCLUDE                         88
#define TK_GROUPS                          89
#define TK_OTHERS                          90
#define TK_TIES                            91
#define TK_REINDEX                         92
#define TK_RENAME                          93
#define TK_CTIME_KW                        94
#define TK_ANY                             95
#define TK_BITAND                          96
#define TK_BITOR                           97
#define TK_LSHIFT                          98
#define TK_RSHIFT                          99
#define TK_PLUS                           100
#define TK_MINUS                          101
#define TK_STAR                           102
#define TK_SLASH                          103
#define TK_REM                            104
#define TK_CONCAT                         105
#define TK_COLLATE                        106
#define TK_BITNOT                         107
#define TK_ON                             108
#define TK_INDEXED                        109
#define TK_STRING                         110
#define TK_JOIN_KW                        111
#define TK_CONSTRAINT                     112
#define TK_DEFAULT                        113
#define TK_NULL                           114
#define TK_PRIMARY                        115
#define TK_UNIQUE                         116
#define TK_CHECK                          117
#define TK_REFERENCES                     118
#define TK_AUTOINCR                       119
#define TK_INSERT                         120
#define TK_DELETE                         121
#define TK_UPDATE                         122
#define TK_SET                            123
#define TK_DEFERRABLE                     124
#define TK_FOREIGN                        125
#define TK_DROP                           126
#define TK_UNION                          127
#define TK_ALL                            128
#define TK_EXCEPT                         129
#define TK_INTERSECT                      130
#define TK_SELECT                         131
#define TK_VALUES                         132
#define TK_DISTINCT                       133
#define TK_DOT                            134
#define TK_FROM                           135
#define TK_JOIN                           136
#define TK_USING                          137
#define TK_ORDER                          138
#define TK_GROUP                          139
#define TK_HAVING                         140
#define TK_LIMIT                          141
#define TK_WHERE                          142
#define TK_INTO                           143
#define TK_NOTHING                        144
#define TK_FLOAT                          145
#define TK_BLOB                           146
#define TK_INTEGER                        147
#define TK_VARIABLE                       148
#define TK_CASE                           149
#define TK_WHEN                           150
#define TK_THEN                           151
#define TK_ELSE                           152
#define TK_INDEX                          153
#define TK_ALTER                          154
#define TK_ADD                            155
#define TK_WINDOW                         156
#define TK_OVER                           157
#define TK_FILTER                         158
#define TK_TRUEFALSE                      159
#define TK_ISNOT                          160
#define TK_FUNCTION                       161
#define TK_COLUMN                         162
#define TK_AGG_FUNCTION                   163
#define TK_AGG_COLUMN                     164
#define TK_UMINUS                         165
#define TK_UPLUS                          166
#define TK_TRUTH                          167
#define TK_REGISTER                       168
#define TK_VECTOR                         169
#define TK_SELECT_COLUMN                  170
#define TK_IF_NULL_ROW                    171
#define TK_ASTERISK                       172
#define TK_SPAN                           173


#define TK_SPACE                          174
#define TK_ILLEGAL                        175








/************** End of parse.h ***********************************************/
/************** Continuing where we left off in sqliteInt.h ******************/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <assert.h>

  int nData;              /* Size of pData.  0 if none. */
  int nZero;              /* Extra zero data appended after pData,nData */
};

SQLITE_PRIVATE int sqlite3BtreeInsert(BtCursor*, const BtreePayload *pPayload,
                       int flags, int seekResult);
SQLITE_PRIVATE int sqlite3BtreeFirst(BtCursor*, int *pRes);



SQLITE_PRIVATE int sqlite3BtreeLast(BtCursor*, int *pRes);
SQLITE_PRIVATE int sqlite3BtreeNext(BtCursor*, int flags);
SQLITE_PRIVATE int sqlite3BtreeEof(BtCursor*);
SQLITE_PRIVATE int sqlite3BtreePrevious(BtCursor*, int flags);
SQLITE_PRIVATE i64 sqlite3BtreeIntegerKey(BtCursor*);
#ifdef SQLITE_ENABLE_OFFSET_SQL_FUNC
SQLITE_PRIVATE i64 sqlite3BtreeOffset(BtCursor*);

#define OP_Cast           85 /* synopsis: affinity(r[P1])                  */
#define OP_Permutation    86
#define OP_Compare        87 /* synopsis: r[P1@P3] <-> r[P2@P3]            */
#define OP_IsTrue         88 /* synopsis: r[P2] = coalesce(r[P1]==TRUE,P3) ^ P4 */
#define OP_Offset         89 /* synopsis: r[P3] = sqlite_offset(P1)        */
#define OP_Column         90 /* synopsis: r[P3]=PX                         */
#define OP_Affinity       91 /* synopsis: affinity(r[P1@P2])               */
#define OP_MakeRecord     92 /* synopsis: r[P3]=mkrec(r[P1@P2])            */
#define OP_Count          93 /* synopsis: r[P2]=count()                    */
#define OP_ReadCookie     94
#define OP_SetCookie      95
#define OP_BitAnd         96 /* same as TK_BITAND, synopsis: r[P3]=r[P1]&r[P2] */
#define OP_BitOr          97 /* same as TK_BITOR, synopsis: r[P3]=r[P1]|r[P2] */
#define OP_ShiftLeft      98 /* same as TK_LSHIFT, synopsis: r[P3]=r[P2]<<r[P1] */
#define OP_ShiftRight     99 /* same as TK_RSHIFT, synopsis: r[P3]=r[P2]>>r[P1] */
#define OP_Add           100 /* same as TK_PLUS, synopsis: r[P3]=r[P1]+r[P2] */
#define OP_Subtract      101 /* same as TK_MINUS, synopsis: r[P3]=r[P2]-r[P1] */
#define OP_Multiply      102 /* same as TK_STAR, synopsis: r[P3]=r[P1]*r[P2] */
#define OP_Divide        103 /* same as TK_SLASH, synopsis: r[P3]=r[P2]/r[P1] */
#define OP_Remainder     104 /* same as TK_REM, synopsis: r[P3]=r[P2]%r[P1] */
#define OP_Concat        105 /* same as TK_CONCAT, synopsis: r[P3]=r[P2]+r[P1] */
#define OP_ReopenIdx     106 /* synopsis: root=P2 iDb=P3                   */
#define OP_BitNot        107 /* same as TK_BITNOT, synopsis: r[P2]= ~r[P1] */




#define OP_OpenRead      108 /* synopsis: root=P2 iDb=P3                   */
#define OP_OpenWrite     109 /* synopsis: root=P2 iDb=P3                   */
#define OP_String8       110 /* same as TK_STRING, synopsis: r[P2]='P4'    */
#define OP_OpenDup       111
#define OP_OpenAutoindex 112 /* synopsis: nColumn=P2                       */
#define OP_OpenEphemeral 113 /* synopsis: nColumn=P2                       */
#define OP_SorterOpen    114
#define OP_SequenceTest  115 /* synopsis: if( cursor[P1].ctr++ ) pc = P2   */
#define OP_OpenPseudo    116 /* synopsis: P3 columns in r[P2]              */
#define OP_Close         117

#define OP_DeferredSeek  134 /* synopsis: Move P3 to P1.rowid if needed    */
#define OP_IdxRowid      135 /* synopsis: r[P2]=rowid                      */
#define OP_Destroy       136
#define OP_Clear         137
#define OP_ResetSorter   138
#define OP_CreateBtree   139 /* synopsis: r[P2]=root iDb=P1 flags=P3       */
#define OP_SqlExec       140

#define OP_ParseSchema   141
#define OP_LoadAnalysis  142
#define OP_DropTable     143
#define OP_DropIndex     144
#define OP_Real          145 /* same as TK_FLOAT, synopsis: r[P2]=P4       */
#define OP_DropTrigger   146
#define OP_IntegrityCk   147
#define OP_RowSetAdd     148 /* synopsis: rowset(P1)=r[P2]                 */
#define OP_Param         149
#define OP_FkCounter     150 /* synopsis: fkctr[P1]+=P2                    */
#define OP_MemMax        151 /* synopsis: r[P1]=max(r[P1],r[P2])           */
#define OP_OffsetLimit   152 /* synopsis: if r[P1]>0 then r[P2]=r[P1]+max(0,r[P3]) else r[P2]=(-1) */

/*  32 */ 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01,\
/*  40 */ 0x01, 0x23, 0x0b, 0x26, 0x26, 0x01, 0x01, 0x03,\
/*  48 */ 0x03, 0x03, 0x03, 0x03, 0x0b, 0x0b, 0x0b, 0x0b,\
/*  56 */ 0x0b, 0x0b, 0x01, 0x01, 0x01, 0x01, 0x00, 0x00,\
/*  64 */ 0x00, 0x00, 0x02, 0x02, 0x08, 0x00, 0x10, 0x10,\
/*  72 */ 0x10, 0x10, 0x00, 0x10, 0x10, 0x00, 0x00, 0x10,\
/*  80 */ 0x10, 0x00, 0x00, 0x02, 0x02, 0x02, 0x00, 0x00,\
/*  88 */ 0x12, 0x20, 0x00, 0x00, 0x00, 0x10, 0x10, 0x00,\
/*  96 */ 0x26, 0x26, 0x26, 0x26, 0x26, 0x26, 0x26, 0x26,\
/* 104 */ 0x26, 0x26, 0x00, 0x12, 0x00, 0x00, 0x10, 0x00,\
/* 112 */ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,\
/* 120 */ 0x10, 0x10, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,\
/* 128 */ 0x10, 0x00, 0x00, 0x04, 0x04, 0x00, 0x00, 0x10,\
/* 136 */ 0x10, 0x00, 0x00, 0x10, 0x00, 0x00, 0x00, 0x00,\
/* 144 */ 0x00, 0x10, 0x00, 0x00, 0x06, 0x10, 0x00, 0x04,\
/* 152 */ 0x1a, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,\
/* 160 */ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x10, 0x10,\
/* 168 */ 0x00, 0x00, 0x00, 0x00, 0x00,}

/* The sqlite3P2Values() routine is able to run faster if it knows
** the value of the largest JUMP opcode.  The smaller the maximum
** JUMP opcode the better, so the mkopcodeh.tcl script that

#endif
  void *pCommitArg;                 /* Argument to xCommitCallback() */
  int (*xCommitCallback)(void*);    /* Invoked at every commit. */
  void *pRollbackArg;               /* Argument to xRollbackCallback() */
  void (*xRollbackCallback)(void*); /* Invoked at every commit. */
  void *pUpdateArg;
  void (*xUpdateCallback)(void*,int, const char*,const char*,sqlite_int64);
  Parse *pParse;                /* Current parse */
#ifdef SQLITE_ENABLE_PREUPDATE_HOOK
  void *pPreUpdateArg;          /* First argument to xPreUpdateCallback */
  void (*xPreUpdateCallback)(   /* Registered using sqlite3_preupdate_hook() */
    void*,sqlite3*,int,char const*,char const*,sqlite3_int64,sqlite3_int64
  );
  PreUpdate *pPreUpdate;        /* Context for active pre-update callback */
#endif /* SQLITE_ENABLE_PREUPDATE_HOOK */

/*
** Allowed values for sqlite3.mDbFlags
*/
#define DBFLAG_SchemaChange   0x0001  /* Uncommitted Hash table changes */
#define DBFLAG_PreferBuiltin  0x0002  /* Preference to built-in funcs */
#define DBFLAG_Vacuum         0x0004  /* Currently in a VACUUM */
#define DBFLAG_VacuumInto     0x0008  /* Currently running VACUUM INTO */
#define DBFLAG_SchemaKnownOk  0x0010  /* Schema is known to be valid */

/*
** Bits of the sqlite3.dbOptFlags field that are used by the
** sqlite3_test_control(SQLITE_TESTCTRL_OPTIMIZATIONS,...) interface to
** selectively disable various optimizations.
*/
#define SQLITE_QueryFlattener 0x0001   /* Query flattening */
#define SQLITE_WindowFunc     0x0002   /* Use xInverse for window functions */
#define SQLITE_GroupByOrder   0x0004   /* GROUPBY cover of ORDERBY */
#define SQLITE_FactorOutConst 0x0008   /* Constant factoring */
#define SQLITE_DistinctOpt    0x0010   /* DISTINCT using indexes */
#define SQLITE_CoverIdxScan   0x0020   /* Covering index scans */
#define SQLITE_OrderByIdxJoin 0x0040   /* ORDER BY of joins via index */
#define SQLITE_Transitive     0x0080   /* Transitive constraints */
#define SQLITE_OmitNoopJoin   0x0100   /* Omit unused tables in joins */

#define SQLITE_FUNC_CONSTANT 0x0800 /* Constant inputs give a constant output */
#define SQLITE_FUNC_MINMAX   0x1000 /* True for min() and max() aggregates */
#define SQLITE_FUNC_SLOCHNG  0x2000 /* "Slow Change". Value constant during a
                                    ** single query - might change over time */
#define SQLITE_FUNC_AFFINITY 0x4000 /* Built-in affinity() function */
#define SQLITE_FUNC_OFFSET   0x8000 /* Built-in sqlite_offset() function */
#define SQLITE_FUNC_WINDOW   0x00010000 /* Built-in window-only function */

#define SQLITE_FUNC_INTERNAL 0x00040000 /* For use by NestedParse() only */

/*
** The following three macros, FUNCTION(), LIKEFUNC() and AGGREGATE() are
** used to create the initializers for the FuncDef structures.
**
**   FUNCTION(zName, nArg, iArg, bNC, xFunc)

      int regReturn;         /* Register used to hold return address */
    } sub;
  } y;
};

/*
** The following are the meanings of bits in the Expr.flags field.
** Value restrictions:
**
**          EP_Agg == NC_HasAgg == SF_HasAgg
**          EP_Win == NC_HasWin
*/
#define EP_FromJoin  0x000001 /* Originates in ON/USING clause of outer join */
#define EP_Distinct  0x000002 /* Aggregate function with DISTINCT keyword */
#define EP_HasFunc   0x000004 /* Contains one or more functions of any kind */
#define EP_FixedCol  0x000008 /* TK_Column with a known fixed value */
#define EP_Agg       0x000010 /* Contains one or more aggregate functions */
#define EP_VarSelect 0x000020 /* pSelect is correlated, not constant */
#define EP_DblQuoted 0x000040 /* token.z was originally in "..." */
#define EP_InfixFunc 0x000080 /* True for an infix function: LIKE, GLOB, etc */
#define EP_Collate   0x000100 /* Tree contains a TK_COLLATE operator */
#define EP_Generic   0x000200 /* Ignore COLLATE or affinity on this tree */
#define EP_IntValue  0x000400 /* Integer value contained in u.iValue */
#define EP_xIsSelect 0x000800 /* x.pSelect is valid (otherwise x.pList is) */
#define EP_Skip      0x001000 /* COLLATE, AS, or UNLIKELY */
#define EP_Reduced   0x002000 /* Expr struct EXPR_REDUCEDSIZE bytes only */
#define EP_TokenOnly 0x004000 /* Expr struct EXPR_TOKENONLYSIZE bytes only */
#define EP_Win       0x008000 /* Contains window functions */
#define EP_MemToken  0x010000 /* Need to sqlite3DbFree() Expr.zToken */
#define EP_NoReduce  0x020000 /* Cannot EXPRDUP_REDUCE this Expr */
#define EP_Unlikely  0x040000 /* unlikely() or likelihood() function */
#define EP_ConstFunc 0x080000 /* A SQLITE_FUNC_CONSTANT or _SLOCHNG function */
#define EP_CanBeNull 0x100000 /* Can be null despite NOT NULL constraint */
#define EP_Subquery  0x200000 /* Tree contains a TK_SELECT operator */
#define EP_Alias     0x400000 /* Is an alias for a result set column */
#define EP_Leaf      0x800000 /* Expr.pLeft, .pRight, .u.pSelect all NULL */
#define EP_WinFunc  0x1000000 /* TK_FUNCTION with Expr.y.pWin set */
#define EP_Subrtn   0x2000000 /* Uses Expr.y.sub. TK_IN, _SELECT, or _EXISTS */
#define EP_Quoted   0x4000000 /* TK_ID was originally quoted */
#define EP_Static   0x8000000 /* Held in memory not obtained from malloc() */

/*
** The EP_Propagate mask is a set of properties that automatically propagate
** upwards into parent nodes.
*/
#define EP_Propagate (EP_Collate|EP_Subquery|EP_HasFunc)

  Select *pWinSelect;  /* SELECT statement for any window functions */
};

/*
** Allowed values for the NameContext, ncFlags field.
**
** Value constraints (all checked via assert()):
**    NC_HasAgg    == SF_HasAgg    == EP_Agg
**    NC_MinMaxAgg == SF_MinMaxAgg == SQLITE_FUNC_MINMAX
**    NC_HasWin    == EP_Win
**
*/
#define NC_AllowAgg  0x0001  /* Aggregate functions are allowed here */
#define NC_PartIdx   0x0002  /* True if resolving a partial index WHERE */
#define NC_IsCheck   0x0004  /* True if resolving names in a CHECK constraint */
#define NC_InAggFunc 0x0008  /* True if analyzing arguments to an agg func */
#define NC_HasAgg    0x0010  /* One or more aggregate functions seen */
#define NC_IdxExpr   0x0020  /* True if resolving columns of CREATE INDEX */
#define NC_VarSelect 0x0040  /* A correlated subquery has been seen */
#define NC_UEList    0x0080  /* True if uNC.pEList is used */
#define NC_UAggInfo  0x0100  /* True if uNC.pAggInfo is used */
#define NC_UUpsert   0x0200  /* True if uNC.pUpsert is used */
#define NC_MinMaxAgg 0x1000  /* min/max aggregates seen.  See note above */
#define NC_Complex   0x2000  /* True if a function or subquery seen */
#define NC_AllowWin  0x4000  /* Window functions are allowed here */
#define NC_HasWin    0x8000  /* One or more window functions seen */

/*
** An instance of the following object describes a single ON CONFLICT
** clause in an upsert.
**
** The pUpsertTarget field is only set if the ON CONFLICT clause includes
** conflict-target clause.  (In "ON CONFLICT(a,b)" the "(a,b)" is the

#ifndef SQLITE_OMIT_SHARED_CACHE
  int nTableLock;        /* Number of locks in aTableLock */
  TableLock *aTableLock; /* Required table locks for shared-cache mode */
#endif
  AutoincInfo *pAinc;  /* Information about AUTOINCREMENT counters */
  Parse *pToplevel;    /* Parse structure for main program (or NULL) */
  Table *pTriggerTab;  /* Table triggers are being coded for */
  Parse *pParentParse; /* Parent parser if this parser is nested */
  int addrCrTab;       /* Address of OP_CreateBtree opcode on CREATE TABLE */
  u32 nQueryLoop;      /* Est number of iterations of a query (10*log2(N)) */
  u32 oldmask;         /* Mask of old.* columns referenced */
  u32 newmask;         /* Mask of new.* columns referenced */
  u8 eTriggerOp;       /* TK_UPDATE, TK_INSERT or TK_DELETE */
  u8 eOrconf;          /* Default ON CONFLICT policy for trigger steps */
  u8 disableTriggers;  /* True to disable triggers */

struct TreeView {
  int iLevel;             /* Which level of the tree we are on */
  u8  bLine[100];         /* Draw vertical in column i if bLine[i] is true */
};
#endif /* SQLITE_DEBUG */

/*
** This object is used in various ways, all related to window functions
**
**   (1) A single instance of this structure is attached to the
**       the Expr.pWin field for each window function in an expression tree.
**       This object holds the information contained in the OVER clause,
**       plus additional fields used during code generation.
**
**   (2) All window functions in a single SELECT form a linked-list
**       attached to Select.pWin.  The Window.pFunc and Window.pExpr
**       fields point back to the expression that is the window function.
**
**   (3) The terms of the WINDOW clause of a SELECT are instances of this
**       object on a linked list attached to Select.pWinDefn.
**
** The uses (1) and (2) are really the same Window object that just happens
** to be accessible in two different ways.  Use case (3) are separate objects.
*/
struct Window {
  char *zName;            /* Name of window (may be NULL) */
  char *zBase;            /* Name of base window for chaining (may be NULL) */
  ExprList *pPartition;   /* PARTITION BY clause */
  ExprList *pOrderBy;     /* ORDER BY clause */
  u8 eFrmType;            /* TK_RANGE, TK_GROUPS, TK_ROWS, or 0 */
  u8 eStart;              /* UNBOUNDED, CURRENT, PRECEDING or FOLLOWING */
  u8 eEnd;                /* UNBOUNDED, CURRENT, PRECEDING or FOLLOWING */
  u8 bImplicitFrame;      /* True if frame was implicitly specified */
  u8 eExclude;            /* TK_NO, TK_CURRENT, TK_TIES, TK_GROUP, or 0 */
  Expr *pStart;           /* Expression for "<expr> PRECEDING" */
  Expr *pEnd;             /* Expression for "<expr> FOLLOWING" */
  Window *pNextWin;       /* Next window function belonging to this SELECT */
  Expr *pFilter;          /* The FILTER expression */
  FuncDef *pFunc;         /* The function */
  int iEphCsr;            /* Partition buffer or Peer buffer */
  int regAccum;
  int regResult;
  int csrApp;             /* Function cursor (used by min/max) */
  int regApp;             /* Function register (also used by min/max) */
  int regPart;            /* Array of registers for PARTITION BY values */

  Expr *pOwner;           /* Expression object this window is attached to */
  int nBufferCol;         /* Number of columns in buffer table */
  int iArgCol;            /* Offset of first argument for this function */
  int regOne;             /* Register containing constant value 1 */
  int regStartRowid;
  int regEndRowid;
};

#ifndef SQLITE_OMIT_WINDOWFUNC
SQLITE_PRIVATE void sqlite3WindowDelete(sqlite3*, Window*);
SQLITE_PRIVATE void sqlite3WindowListDelete(sqlite3 *db, Window *p);
SQLITE_PRIVATE Window *sqlite3WindowAlloc(Parse*, int, int, Expr*, int , Expr*, u8);
SQLITE_PRIVATE void sqlite3WindowAttach(Parse*, Expr*, Window*);
SQLITE_PRIVATE int sqlite3WindowCompare(Parse*, Window*, Window*);
SQLITE_PRIVATE void sqlite3WindowCodeInit(Parse*, Window*);
SQLITE_PRIVATE void sqlite3WindowCodeStep(Parse*, Select*, WhereInfo*, int, int);
SQLITE_PRIVATE int sqlite3WindowRewrite(Parse*, Select*);
SQLITE_PRIVATE int sqlite3ExpandSubquery(Parse*, struct SrcList_item*);
SQLITE_PRIVATE void sqlite3WindowUpdate(Parse*, Window*, Window*, FuncDef*);
SQLITE_PRIVATE Window *sqlite3WindowDup(sqlite3 *db, Expr *pOwner, Window *p);
SQLITE_PRIVATE Window *sqlite3WindowListDup(sqlite3 *db, Window *p);
SQLITE_PRIVATE void sqlite3WindowFunctions(void);
SQLITE_PRIVATE void sqlite3WindowChain(Parse*, Window*, Window*);
SQLITE_PRIVATE Window *sqlite3WindowAssemble(Parse*, Window*, ExprList*, ExprList*, Token*);
#else
# define sqlite3WindowDelete(a,b)
# define sqlite3WindowFunctions()
# define sqlite3WindowAttach(a,b,c)
#endif

/*

SQLITE_PRIVATE   void sqlite3TreeViewWinFunc(TreeView*, const Window*, u8);
#endif
#endif


SQLITE_PRIVATE void sqlite3SetString(char **, sqlite3*, const char*);
SQLITE_PRIVATE void sqlite3ErrorMsg(Parse*, const char*, ...);
SQLITE_PRIVATE int sqlite3ErrorToParser(sqlite3*,int);
SQLITE_PRIVATE void sqlite3Dequote(char*);
SQLITE_PRIVATE void sqlite3DequoteExpr(Expr*);
SQLITE_PRIVATE void sqlite3TokenInit(Token*,char*);
SQLITE_PRIVATE int sqlite3KeywordCode(const unsigned char*, int);
SQLITE_PRIVATE int sqlite3RunParser(Parse*, const char*, char **);
SQLITE_PRIVATE void sqlite3FinishCoding(Parse*);
SQLITE_PRIVATE int sqlite3GetTempReg(Parse*);

*/
#define MEM_Null      0x0001   /* Value is NULL (or a pointer) */
#define MEM_Str       0x0002   /* Value is a string */
#define MEM_Int       0x0004   /* Value is an integer */
#define MEM_Real      0x0008   /* Value is a real number */
#define MEM_Blob      0x0010   /* Value is a BLOB */
#define MEM_AffMask   0x001f   /* Mask of affinity bits */
#define MEM_FromBind  0x0020   /* Value originates from sqlite3_bind() */
/* Available          0x0040   */
#define MEM_Undefined 0x0080   /* Value is undefined */
#define MEM_Cleared   0x0100   /* NULL set by OP_Null, not from data */
#define MEM_TypeMask  0xc1df   /* Mask of type bits */


/* Whenever Mem contains a valid string or blob representation, one of
** the following flags must be set to determine the memory management
** policy for Mem.z.  The MEM_Term flag tells us whether or not the
** string is \000 or \u0000 terminated
*/

/*
** Clear any existing type flags from a Mem and replace them with f
*/
#define MemSetTypeFlag(p, f) \
   ((p)->flags = ((p)->flags&~(MEM_TypeMask|MEM_Zero))|f)

/*
** True if Mem X is a NULL-nochng type.
*/
#define MemNullNochng(X) \
  ((X)->flags==(MEM_Null|MEM_Zero) && (X)->n==0 && (X)->u.nZero==0)

/*
** Return true if a memory cell is not marked as invalid.  This macro
** is for use inside assert() statements only.
*/
#ifdef SQLITE_DEBUG
#define memIsValid(M)  ((M)->flags & MEM_Undefined)==0
#endif

SQLITE_PRIVATE void sqlite3OomFault(sqlite3 *db){
  if( db->mallocFailed==0 && db->bBenignMalloc==0 ){
    db->mallocFailed = 1;
    if( db->nVdbeExec>0 ){
      db->u1.isInterrupted = 1;
    }
    db->lookaside.bDisable++;
    if( db->pParse ){
      db->pParse->rc = SQLITE_NOMEM_BKPT;
    }
  }
}

/*
** This routine reactivates the memory allocator and clears the
** db->mallocFailed flag as necessary.
**

/*
** Set the StrAccum object to an error mode.
*/
static void setStrAccumError(StrAccum *p, u8 eError){
  assert( eError==SQLITE_NOMEM || eError==SQLITE_TOOBIG );
  p->accError = eError;
  if( p->mxAlloc ) sqlite3_str_reset(p);
  if( eError==SQLITE_TOOBIG ) sqlite3ErrorToParser(p->db, eError);
}

/*
** Extra argument values from a PrintfArguments object
*/
static sqlite3_int64 getIntArg(PrintfArguments *p){
  if( p->nArg<=p->nUsed ) return 0;

** of the output buffer in pAccum, then cause an SQLITE_TOOBIG error.
** Do the size check before the memory allocation to prevent rogue
** SQL from requesting large allocations using the precision or width
** field of the printf() function.
*/
static char *printfTempBuf(sqlite3_str *pAccum, sqlite3_int64 n){
  char *z;
  if( pAccum->accError ) return 0;
  if( n>pAccum->nAlloc && n>pAccum->mxAlloc ){
    setStrAccumError(pAccum, SQLITE_TOOBIG);
    return 0;
  }
  z = sqlite3DbMallocRaw(pAccum->db, n);
  if( z==0 ){
    setStrAccumError(pAccum, SQLITE_NOMEM);

  assert( p->nChar+(i64)N >= p->nAlloc ); /* Only called if really needed */
  if( p->accError ){
    testcase(p->accError==SQLITE_TOOBIG);
    testcase(p->accError==SQLITE_NOMEM);
    return 0;
  }
  if( p->mxAlloc==0 ){

    setStrAccumError(p, SQLITE_TOOBIG);
    return p->nAlloc - p->nChar - 1;
  }else{
    char *zOld = isMalloced(p) ? p->zText : 0;
    i64 szNew = p->nChar;
    szNew += N + 1;
    if( szNew+p->nChar<=p->mxAlloc ){
      /* Force exponential buffer size growth as long as it does not overflow,
      ** to avoid having to call this routine too often */

** Append N bytes of text from z to the StrAccum object.  Increase the
** size of the memory allocation for StrAccum if necessary.
*/
SQLITE_API void sqlite3_str_append(sqlite3_str *p, const char *z, int N){
  assert( z!=0 || N==0 );
  assert( p->zText!=0 || p->nChar==0 || p->accError );
  assert( N>=0 );
  assert( p->accError==0 || p->nAlloc==0 || p->mxAlloc==0 );
  if( p->nChar+N >= p->nAlloc ){
    enlargeAndAppend(p,z,N);
  }else if( N ){
    assert( p->zText );
    p->nChar += N;
    memcpy(&p->zText[p->nChar-N], z, N);
  }

#endif /* SQLITE_OMIT_WINDOWFUNC */

#ifndef SQLITE_OMIT_WINDOWFUNC
/*
** Generate a human-readable explanation for a Window object
*/
SQLITE_PRIVATE void sqlite3TreeViewWindow(TreeView *pView, const Window *pWin, u8 more){
  int nElement = 0;
  if( pWin->pFilter ){
    sqlite3TreeViewItem(pView, "FILTER", 1);
    sqlite3TreeViewExpr(pView, pWin->pFilter, 0);
    sqlite3TreeViewPop(pView);
  }
  pView = sqlite3TreeViewPush(pView, more);
  if( pWin->zName ){
    sqlite3TreeViewLine(pView, "OVER %s (%p)", pWin->zName, pWin);
  }else{
    sqlite3TreeViewLine(pView, "OVER (%p)", pWin);
  }
  if( pWin->zBase )    nElement++;
  if( pWin->pOrderBy ) nElement++;
  if( pWin->eFrmType ) nElement++;
  if( pWin->eExclude ) nElement++;
  if( pWin->zBase ){
    sqlite3TreeViewPush(pView, (--nElement)>0);
    sqlite3TreeViewLine(pView, "window: %s", pWin->zBase);
    sqlite3TreeViewPop(pView);
  }
  if( pWin->pPartition ){
    sqlite3TreeViewExprList(pView, pWin->pPartition, nElement>0,"PARTITION-BY");
  }
  if( pWin->pOrderBy ){
    sqlite3TreeViewExprList(pView, pWin->pOrderBy, (--nElement)>0, "ORDER-BY");
  }
  if( pWin->eFrmType ){
    char zBuf[30];
    const char *zFrmType = "ROWS";
    if( pWin->eFrmType==TK_RANGE ) zFrmType = "RANGE";
    if( pWin->eFrmType==TK_GROUPS ) zFrmType = "GROUPS";
    sqlite3_snprintf(sizeof(zBuf),zBuf,"%s%s",zFrmType,
        pWin->bImplicitFrame ? " (implied)" : "");
    sqlite3TreeViewItem(pView, zBuf, (--nElement)>0);
    sqlite3TreeViewBound(pView, pWin->eStart, pWin->pStart, 1);
    sqlite3TreeViewBound(pView, pWin->eEnd, pWin->pEnd, 0);
    sqlite3TreeViewPop(pView);
  }
  if( pWin->eExclude ){
    char zBuf[30];
    const char *zExclude;
    switch( pWin->eExclude ){
      case TK_NO:      zExclude = "NO OTHERS";   break;
      case TK_CURRENT: zExclude = "CURRENT ROW"; break;
      case TK_GROUP:   zExclude = "GROUP";       break;
      case TK_TIES:    zExclude = "TIES";        break;
      default:
        sqlite3_snprintf(sizeof(zBuf),zBuf,"invalid(%d)", pWin->eExclude);
        zExclude = zBuf;
        break;
    }
    sqlite3TreeViewPush(pView, 0);
    sqlite3TreeViewLine(pView, "EXCLUDE %s", zExclude);
    sqlite3TreeViewPop(pView);
  }
  sqlite3TreeViewPop(pView);
}
#endif /* SQLITE_OMIT_WINDOWFUNC */

#ifndef SQLITE_OMIT_WINDOWFUNC
/*
** Generate a human-readable explanation for a Window Function object

#ifndef SQLITE_OMIT_UTF16
/*
** This routine transforms the internal text encoding used by pMem to
** desiredEnc. It is an error if the string is already of the desired
** encoding, or if *pMem does not contain a string value.
*/
SQLITE_PRIVATE SQLITE_NOINLINE int sqlite3VdbeMemTranslate(Mem *pMem, u8 desiredEnc){
  sqlite3_int64 len;          /* Maximum length of output string in bytes */
  unsigned char *zOut;        /* Output buffer */
  unsigned char *zIn;         /* Input iterator */
  unsigned char *zTerm;       /* End of input */
  unsigned char *z;           /* Output iterator */
  unsigned int c;

  assert( pMem->db==0 || sqlite3_mutex_held(pMem->db->mutex) );
  assert( pMem->flags&MEM_Str );
  assert( pMem->enc!=desiredEnc );
  assert( pMem->enc!=0 );
  assert( pMem->n>=0 );

  if( desiredEnc==SQLITE_UTF8 ){
    /* When converting from UTF-16, the maximum growth results from
    ** translating a 2-byte character to a 4-byte UTF-8 character.
    ** A single byte is required for the output string
    ** nul-terminator.
    */
    pMem->n &= ~1;
    len = 2 * (sqlite3_int64)pMem->n + 1;
  }else{
    /* When converting from UTF-8 to UTF-16 the maximum growth is caused
    ** when a 1-byte UTF-8 character is translated into a 2-byte UTF-16
    ** character. Two bytes are required in the output buffer for the
    ** nul-terminator.
    */
    len = 2 * (sqlite3_int64)pMem->n + 2;
  }

  /* Set zIn to point at the start of the input buffer and zTerm to point 1
  ** byte past the end.
  **
  ** Variable zOut is set to point at the output buffer, space obtained
  ** from sqlite3_malloc().

SQLITE_PRIVATE void sqlite3Coverage(int x){
  static unsigned dummy = 0;
  dummy += (unsigned)x;
}
#endif

/*
** Calls to sqlite3FaultSim() are used to simulate a failure during testing,
** or to bypass normal error detection during testing in order to let 
** execute proceed futher downstream.
**
** In deployment, sqlite3FaultSim() *always* return SQLITE_OK (0).  The
** sqlite3FaultSim() function only returns non-zero during testing.
**
** During testing, if the test harness has set a fault-sim callback using
** a call to sqlite3_test_control(SQLITE_TESTCTRL_FAULT_INSTALL), then
** each call to sqlite3FaultSim() is relayed to that application-supplied
** callback and the integer return value form the application-supplied
** callback is returned by sqlite3FaultSim().
**
** The integer argument to sqlite3FaultSim() is a code to identify which
** sqlite3FaultSim() instance is being invoked. Each call to sqlite3FaultSim()
** should have a unique code.  To prevent legacy testing applications from
** breaking, the codes should not be changed or reused.
*/
#ifndef SQLITE_UNTESTABLE
SQLITE_PRIVATE int sqlite3FaultSim(int iTest){
  int (*xCallback)(int) = sqlite3GlobalConfig.xTestCallback;
  return xCallback ? xCallback(iTest) : SQLITE_OK;
}
#endif

  }else{
    pParse->nErr++;
    sqlite3DbFree(db, pParse->zErrMsg);
    pParse->zErrMsg = zMsg;
    pParse->rc = SQLITE_ERROR;
  }
}

/*
** If database connection db is currently parsing SQL, then transfer
** error code errCode to that parser if the parser has not already
** encountered some other kind of error.
*/
SQLITE_PRIVATE int sqlite3ErrorToParser(sqlite3 *db, int errCode){
  Parse *pParse;
  if( db==0 || (pParse = db->pParse)==0 ) return errCode;
  pParse->rc = errCode;
  pParse->nErr++;
  return errCode;
}

/*
** Convert an SQL-style quoted string into a normal string by removing
** the quote characters.  The conversion is done in-place.  If the
** input does not begin with a quote character, then this routine
** is a no-op.
**

  char *z;               /* Pointer to where zName will be stored */
  int i;                 /* Index in pIn[] where zName is stored */

  nInt = nName/4 + 3;
  assert( pIn==0 || pIn[0]>=3 );  /* Verify ok to add new elements */
  if( pIn==0 || pIn[1]+nInt > pIn[0] ){
    /* Enlarge the allocation */
    sqlite3_int64 nAlloc = (pIn ? 2*(sqlite3_int64)pIn[0] : 10) + nInt;
    VList *pOut = sqlite3DbRealloc(db, pIn, nAlloc*sizeof(int));
    if( pOut==0 ) return pIn;
    if( pIn==0 ) pOut[1] = 2;
    pIn = pOut;
    pIn[0] = nAlloc;
  }
  i = pIn[1];

*/
static HashElem *findElementWithHash(
  const Hash *pH,     /* The pH to be searched */
  const char *pKey,   /* The key we are searching for */
  unsigned int *pHash /* Write the hash value here */
){
  HashElem *elem;                /* Used to loop thru the element list */
  unsigned int count;            /* Number of elements left to test */
  unsigned int h;                /* The computed hash */
  static HashElem nullElement = { 0, 0, 0, 0 };

  if( pH->ht ){   /*OPTIMIZATION-IF-TRUE*/
    struct _ht *pEntry;
    h = strHash(pKey) % pH->htsize;
    pEntry = &pH->ht[h];

    elem->next->prev = elem->prev;
  }
  if( pH->ht ){
    pEntry = &pH->ht[h];
    if( pEntry->chain==elem ){
      pEntry->chain = elem->next;
    }
    assert( pEntry->count>0 );
    pEntry->count--;
  }
  sqlite3_free( elem );
  pH->count--;
  if( pH->count==0 ){
    assert( pH->first==0 );
    assert( pH->count==0 );
    sqlite3HashClear(pH);

    /*  85 */ "Cast"             OpHelp("affinity(r[P1])"),
    /*  86 */ "Permutation"      OpHelp(""),
    /*  87 */ "Compare"          OpHelp("r[P1@P3] <-> r[P2@P3]"),
    /*  88 */ "IsTrue"           OpHelp("r[P2] = coalesce(r[P1]==TRUE,P3) ^ P4"),
    /*  89 */ "Offset"           OpHelp("r[P3] = sqlite_offset(P1)"),
    /*  90 */ "Column"           OpHelp("r[P3]=PX"),
    /*  91 */ "Affinity"         OpHelp("affinity(r[P1@P2])"),
    /*  92 */ "MakeRecord"       OpHelp("r[P3]=mkrec(r[P1@P2])"),
    /*  93 */ "Count"            OpHelp("r[P2]=count()"),
    /*  94 */ "ReadCookie"       OpHelp(""),
    /*  95 */ "SetCookie"        OpHelp(""),
    /*  96 */ "BitAnd"           OpHelp("r[P3]=r[P1]&r[P2]"),
    /*  97 */ "BitOr"            OpHelp("r[P3]=r[P1]|r[P2]"),
    /*  98 */ "ShiftLeft"        OpHelp("r[P3]=r[P2]<<r[P1]"),
    /*  99 */ "ShiftRight"       OpHelp("r[P3]=r[P2]>>r[P1]"),
    /* 100 */ "Add"              OpHelp("r[P3]=r[P1]+r[P2]"),
    /* 101 */ "Subtract"         OpHelp("r[P3]=r[P2]-r[P1]"),
    /* 102 */ "Multiply"         OpHelp("r[P3]=r[P1]*r[P2]"),
    /* 103 */ "Divide"           OpHelp("r[P3]=r[P2]/r[P1]"),
    /* 104 */ "Remainder"        OpHelp("r[P3]=r[P2]%r[P1]"),
    /* 105 */ "Concat"           OpHelp("r[P3]=r[P2]+r[P1]"),
    /* 106 */ "ReopenIdx"        OpHelp("root=P2 iDb=P3"),
    /* 107 */ "BitNot"           OpHelp("r[P2]= ~r[P1]"),





    /* 108 */ "OpenRead"         OpHelp("root=P2 iDb=P3"),
    /* 109 */ "OpenWrite"        OpHelp("root=P2 iDb=P3"),
    /* 110 */ "String8"          OpHelp("r[P2]='P4'"),
    /* 111 */ "OpenDup"          OpHelp(""),
    /* 112 */ "OpenAutoindex"    OpHelp("nColumn=P2"),
    /* 113 */ "OpenEphemeral"    OpHelp("nColumn=P2"),
    /* 114 */ "SorterOpen"       OpHelp(""),
    /* 115 */ "SequenceTest"     OpHelp("if( cursor[P1].ctr++ ) pc = P2"),
    /* 116 */ "OpenPseudo"       OpHelp("P3 columns in r[P2]"),
    /* 117 */ "Close"            OpHelp(""),

    /* 134 */ "DeferredSeek"     OpHelp("Move P3 to P1.rowid if needed"),
    /* 135 */ "IdxRowid"         OpHelp("r[P2]=rowid"),
    /* 136 */ "Destroy"          OpHelp(""),
    /* 137 */ "Clear"            OpHelp(""),
    /* 138 */ "ResetSorter"      OpHelp(""),
    /* 139 */ "CreateBtree"      OpHelp("r[P2]=root iDb=P1 flags=P3"),
    /* 140 */ "SqlExec"          OpHelp(""),

    /* 141 */ "ParseSchema"      OpHelp(""),
    /* 142 */ "LoadAnalysis"     OpHelp(""),
    /* 143 */ "DropTable"        OpHelp(""),
    /* 144 */ "DropIndex"        OpHelp(""),
    /* 145 */ "Real"             OpHelp("r[P2]=P4"),
    /* 146 */ "DropTrigger"      OpHelp(""),
    /* 147 */ "IntegrityCk"      OpHelp(""),
    /* 148 */ "RowSetAdd"        OpHelp("rowset(P1)=r[P2]"),
    /* 149 */ "Param"            OpHelp(""),
    /* 150 */ "FkCounter"        OpHelp("fkctr[P1]+=P2"),
    /* 151 */ "MemMax"           OpHelp("r[P1]=max(r[P1],r[P2])"),
    /* 152 */ "OffsetLimit"      OpHelp("if r[P1]>0 then r[P2]=r[P1]+max(0,r[P3]) else r[P2]=(-1)"),

/*
** Malloc function used by SQLite to obtain space from the buffer configured
** using sqlite3_config(SQLITE_CONFIG_PAGECACHE) option. If no such buffer
** exists, this function falls back to sqlite3Malloc().
*/
SQLITE_PRIVATE void *sqlite3PageMalloc(int sz){


  assert( sz<=65536+8 ); /* These allocations are never very large */
  return pcache1Alloc(sz);
}

/*
** Free an allocated buffer obtained from sqlite3PageMalloc().
*/
SQLITE_PRIVATE void sqlite3PageFree(void *p){

**   * the database file is open,
**   * there are no dirty pages in the cache, and
**   * the desired page is not currently in the wal file.
*/
SQLITE_PRIVATE int sqlite3PagerDirectReadOk(Pager *pPager, Pgno pgno){
  if( pPager->fd->pMethods==0 ) return 0;
  if( sqlite3PCacheIsDirty(pPager->pPCache) ) return 0;
#ifdef SQLITE_HAS_CODEC
  if( pPager->xCodec!=0 ) return 0;
#endif
#ifndef SQLITE_OMIT_WAL
  if( pPager->pWal ){
    u32 iRead = 0;
    int rc;
    rc = sqlite3WalFindFrame(pPager->pWal, pgno, &iRead);
    return (rc==SQLITE_OK && iRead==0);
  }

    char *pNew = NULL;             /* New temp space */
    i64 nByte = 0;

    if( pPager->eState>PAGER_OPEN && isOpen(pPager->fd) ){
      rc = sqlite3OsFileSize(pPager->fd, &nByte);
    }
    if( rc==SQLITE_OK ){
      /* 8 bytes of zeroed overrun space is sufficient so that the b-tree
      * cell header parser will never run off the end of the allocation */
      pNew = (char *)sqlite3PageMalloc(pageSize+8);
      if( !pNew ){
        rc = SQLITE_NOMEM_BKPT;
      }else{
        memset(pNew+pageSize, 0, 8);
      }
    }

    if( rc==SQLITE_OK ){
      pager_reset(pPager);
      rc = sqlite3PcacheSetPageSize(pPager->pPCache, pageSize);
    }
    if( rc==SQLITE_OK ){

  /* If the cache contains a page with page-number pgno, remove it
  ** from its hash chain. Also, if the PGHDR_NEED_SYNC flag was set for 
  ** page pgno before the 'move' operation, it needs to be retained 
  ** for the page moved there.
  */
  pPg->flags &= ~PGHDR_NEED_SYNC;
  pPgOld = sqlite3PagerLookup(pPager, pgno);
  assert( !pPgOld || pPgOld->nRef==1 || CORRUPT_DB );
  if( pPgOld ){
    if( pPgOld->nRef>1 ){
      sqlite3PagerUnrefNotNull(pPgOld);
      return SQLITE_CORRUPT_BKPT;
    }
    pPg->flags |= (pPgOld->flags&PGHDR_NEED_SYNC);
    if( pPager->tempFile ){
      /* Do not discard pages from an in-memory database since we might
      ** need to rollback later.  Just move the page out of the way. */
      sqlite3PcacheMove(pPgOld, pPager->dbSize+1);
    }else{
      sqlite3PcacheDrop(pPgOld);

/*
** Release a lock obtained by an earlier successful call to
** sqlite3PagerSnapshotCheck().
*/
SQLITE_PRIVATE void sqlite3PagerSnapshotUnlock(Pager *pPager){
  assert( pPager->pWal );
  sqlite3WalSnapshotUnlock(pPager->pWal);
}

#endif /* SQLITE_ENABLE_SNAPSHOT */
#endif /* !SQLITE_OMIT_WAL */

#ifdef SQLITE_ENABLE_ZIPVFS
/*

  int iPage,               /* The page we seek */
  volatile u32 **ppPage    /* Write the page pointer here */
){
  int rc = SQLITE_OK;

  /* Enlarge the pWal->apWiData[] array if required */
  if( pWal->nWiData<=iPage ){
    sqlite3_int64 nByte = sizeof(u32*)*(iPage+1);
    volatile u32 **apNew;
    apNew = (volatile u32 **)sqlite3_realloc64((void *)pWal->apWiData, nByte);
    if( !apNew ){
      *ppPage = 0;
      return SQLITE_NOMEM_BKPT;
    }
    memset((void*)&apNew[pWal->nWiData], 0,

    s2 = aIn[1];
  }else{
    s1 = s2 = 0;
  }

  assert( nByte>=8 );
  assert( (nByte&0x00000007)==0 );
  assert( nByte<=65536 );

  if( nativeCksum ){
    do {
      s1 += *aData++ + s2;
      s2 += *aData++ + s1;
    }while( aData<aEnd );
  }else{

** actually needed.
*/
static void walCleanupHash(Wal *pWal){
  WalHashLoc sLoc;                /* Hash table location */
  int iLimit = 0;                 /* Zero values greater than this */
  int nByte;                      /* Number of bytes to zero in aPgno[] */
  int i;                          /* Used to iterate through aHash[] */
  int rc;                         /* Return code form walHashGet() */

  assert( pWal->writeLock );
  testcase( pWal->hdr.mxFrame==HASHTABLE_NPAGE_ONE-1 );
  testcase( pWal->hdr.mxFrame==HASHTABLE_NPAGE_ONE );
  testcase( pWal->hdr.mxFrame==HASHTABLE_NPAGE_ONE+1 );

  if( pWal->hdr.mxFrame==0 ) return;

  /* Obtain pointers to the hash-table and page-number array containing 
  ** the entry that corresponds to frame pWal->hdr.mxFrame. It is guaranteed
  ** that the page said hash-table and array reside on is already mapped.(1)
  */
  assert( pWal->nWiData>walFramePage(pWal->hdr.mxFrame) );
  assert( pWal->apWiData[walFramePage(pWal->hdr.mxFrame)] );
  rc = walHashGet(pWal, walFramePage(pWal->hdr.mxFrame), &sLoc);
  if( NEVER(rc) ) return; /* Defense-in-depth, in case (1) above is wrong */

  /* Zero all hash-table entries that correspond to frame numbers greater
  ** than pWal->hdr.mxFrame.
  */
  iLimit = pWal->hdr.mxFrame - sLoc.iZero;
  assert( iLimit>0 );
  for(i=0; i<HASHTABLE_NSLOT; i++){

** The calling routine should invoke walIteratorFree() to destroy the
** WalIterator object when it has finished with it.
*/
static int walIteratorInit(Wal *pWal, u32 nBackfill, WalIterator **pp){
  WalIterator *p;                 /* Return value */
  int nSegment;                   /* Number of segments to merge */
  u32 iLast;                      /* Last frame in log */
  sqlite3_int64 nByte;            /* Number of bytes to allocate */
  int i;                          /* Iterator variable */
  ht_slot *aTmp;                  /* Temp space used by merge-sort */
  int rc = SQLITE_OK;             /* Return Code */

  /* This routine only runs while holding the checkpoint lock. And
  ** it only runs if there is actually content in the log (mxFrame>0).
  */

  u8 hdrOffset;        /* 100 for page 1.  0 otherwise */
  u8 childPtrSize;     /* 0 if leaf==1.  4 if leaf==0 */
  u8 max1bytePayload;  /* min(maxLocal,127) */
  u8 nOverflow;        /* Number of overflow cell bodies in aCell[] */
  u16 maxLocal;        /* Copy of BtShared.maxLocal or BtShared.maxLeaf */
  u16 minLocal;        /* Copy of BtShared.minLocal or BtShared.minLeaf */
  u16 cellOffset;      /* Index in aData of first cell pointer */
  int nFree;           /* Number of free bytes on the page. -1 for unknown */
  u16 nCell;           /* Number of cells on this page, local and ovfl */
  u16 maskPage;        /* Mask for page offset */
  u16 aiOvfl[4];       /* Insert the i-th overflow cell before the aiOvfl-th
                       ** non-overflow cell */
  u8 *apOvfl[4];       /* Pointers to the body of overflow cells */
  BtShared *pBt;       /* Pointer to BtShared that this page is part of */
  u8 *aData;           /* Pointer to disk image of the page data */

** when saveCursorPosition() was called. Note that this call deletes the 
** saved position info stored by saveCursorPosition(), so there can be
** at most one effective restoreCursorPosition() call after each 
** saveCursorPosition().
*/
static int btreeRestoreCursorPosition(BtCursor *pCur){
  int rc;
  int skipNext = 0;
  assert( cursorOwnsBtShared(pCur) );
  assert( pCur->eState>=CURSOR_REQUIRESEEK );
  if( pCur->eState==CURSOR_FAULT ){
    return pCur->skipNext;
  }
  pCur->eState = CURSOR_INVALID;
  if( sqlite3FaultSim(410) ){
    rc = SQLITE_IOERR;
  }else{
    rc = btreeMoveto(pCur, pCur->pKey, pCur->nKey, 0, &skipNext);
  }
  if( rc==SQLITE_OK ){
    sqlite3_free(pCur->pKey);
    pCur->pKey = 0;
    assert( pCur->eState==CURSOR_VALID || pCur->eState==CURSOR_INVALID );
    if( skipNext ) pCur->skipNext = skipNext;
    if( pCur->skipNext && pCur->eState==CURSOR_VALID ){
      pCur->eState = CURSOR_SKIPNEXT;

  assert( pPage->nOverflow==0 );
  assert( sqlite3_mutex_held(pPage->pBt->mutex) );
  temp = 0;
  src = data = pPage->aData;
  hdr = pPage->hdrOffset;
  cellOffset = pPage->cellOffset;
  nCell = pPage->nCell;
  assert( nCell==get2byte(&data[hdr+3]) || CORRUPT_DB );
  iCellFirst = cellOffset + 2*nCell;
  usableSize = pPage->pBt->usableSize;

  /* This block handles pages with two or fewer free blocks and nMaxFrag
  ** or fewer fragmented bytes. In this case it is faster to move the
  ** two (or one) blocks of cells using memmove() and add the required
  ** offsets to each pointer in the cell-pointer array than it is to 
  ** reconstruct the entire page.  */
  if( (int)data[hdr+7]<=nMaxFrag ){
    int iFree = get2byte(&data[hdr+1]);
    if( iFree>usableSize-4 ) return SQLITE_CORRUPT_PAGE(pPage);




    if( iFree ){
      int iFree2 = get2byte(&data[iFree]);
      if( iFree2>usableSize-4 ) return SQLITE_CORRUPT_PAGE(pPage);
      if( 0==iFree2 || (data[iFree2]==0 && data[iFree2+1]==0) ){
        u8 *pEnd = &data[cellOffset + nCell*2];
        u8 *pAddr;
        int sz2 = 0;
        int sz = get2byte(&data[iFree+2]);
        int top = get2byte(&data[hdr+5]);
        if( top>=iFree ){
          return SQLITE_CORRUPT_PAGE(pPage);
        }
        if( iFree2 ){
          if( iFree+sz>iFree2 ) return SQLITE_CORRUPT_PAGE(pPage);
          sz2 = get2byte(&data[iFree2+2]);
          if( iFree2+sz2 > usableSize ) return SQLITE_CORRUPT_PAGE(pPage);
          memmove(&data[iFree+sz+sz2], &data[iFree+sz], iFree2-(iFree+sz));
          sz += sz2;
        }else if( iFree+sz>usableSize ){
          return SQLITE_CORRUPT_PAGE(pPage);
        }

        cbrk = top+sz;
        assert( cbrk+(iFree-top) <= usableSize );
        memmove(&data[cbrk], &data[top], iFree-top);
        for(pAddr=&data[cellOffset]; pAddr<pEnd; pAddr+=2){
          pc = get2byte(pAddr);
          if( pc<iFree ){ put2byte(pAddr, pc+sz); }
          else if( pc<iFree2 ){ put2byte(pAddr, pc+sz2); }

      src = temp;
    }
    memcpy(&data[cbrk], &src[pc], size);
  }
  data[hdr+7] = 0;

 defragment_out:
  assert( pPage->nFree>=0 );
  if( data[hdr+7]+cbrk-iCellFirst!=pPage->nFree ){
    return SQLITE_CORRUPT_PAGE(pPage);
  }
  assert( cbrk>=iCellFirst );
  put2byte(&data[hdr+5], cbrk);
  data[hdr+1] = 0;
  data[hdr+2] = 0;

** detected then *pRc is set to SQLITE_CORRUPT and NULL is returned.
**
** Slots on the free list that are between 1 and 3 bytes larger than nByte
** will be ignored if adding the extra space to the fragmentation count
** causes the fragmentation count to exceed 60.
*/
static u8 *pageFindSlot(MemPage *pPg, int nByte, int *pRc){
  const int hdr = pPg->hdrOffset;            /* Offset to page header */
  u8 * const aData = pPg->aData;             /* Page data */
  int iAddr = hdr + 1;                       /* Address of ptr to pc */
  int pc = get2byte(&aData[iAddr]);          /* Address of a free slot */
  int x;                                     /* Excess size of the slot */
  int maxPC = pPg->pBt->usableSize - nByte;  /* Max address for a usable slot */
  int size;                                  /* Size of the free slot */

  assert( pc>0 );
  while( pc<=maxPC ){
    /* EVIDENCE-OF: R-22710-53328 The third and fourth bytes of each
    ** freeblock form a big-endian integer which is the size of the freeblock
    ** in bytes, including the 4-byte header. */
    size = get2byte(&aData[pc+2]);
    if( (x = size - nByte)>=0 ){
      testcase( x==4 );
      testcase( x==3 );



      if( x<4 ){
        /* EVIDENCE-OF: R-11498-58022 In a well-formed b-tree page, the total
        ** number of bytes in fragments may not exceed 60. */
        if( aData[hdr+7]>57 ) return 0;

        /* Remove the slot from the free-list. Update the number of
        ** fragmented bytes within the page. */
        memcpy(&aData[iAddr], &aData[pc], 2);
        aData[hdr+7] += (u8)x;
      }else if( x+pc > maxPC ){
        /* This slot extends off the end of the usable part of the page */
        *pRc = SQLITE_CORRUPT_PAGE(pPg);
        return 0;
      }else{
        /* The slot remains on the free-list. Reduce its size to account
        ** for the portion used by the new allocation. */
        put2byte(&aData[pc+2], x);
      }
      return &aData[pc + x];
    }
    iAddr = pc;
    pc = get2byte(&aData[pc]);
    if( pc<=iAddr+size ){

      if( pc ){
        /* The next slot in the chain is not past the end of the current slot */
        *pRc = SQLITE_CORRUPT_PAGE(pPg);
      }
      return 0;
    }
  }
  if( pc>maxPC+nByte-4 ){
    /* The free slot chain extends off the end of the page */
    *pRc = SQLITE_CORRUPT_PAGE(pPg);
  }
  return 0;
}

/*
** Allocate nByte bytes of space from within the B-Tree page passed
** as the first argument. Write into *pIdx the index into pPage->aData[]
** of the first byte of allocated space. Return either SQLITE_OK or

    if( top==0 && pPage->pBt->usableSize==65536 ){
      top = 65536;
    }else{
      return SQLITE_CORRUPT_PAGE(pPage);
    }
  }

  /* If there is enough space between gap and top for one more cell pointer,
  ** and if the freelist is not empty, then search the
  ** freelist looking for a slot big enough to satisfy the request.
  */
  testcase( gap+2==top );
  testcase( gap+1==top );
  testcase( gap==top );
  if( (data[hdr+2] || data[hdr+1]) && gap+2<=top ){
    u8 *pSpace = pageFindSlot(pPage, nByte, &rc);
    if( pSpace ){

  /* The request could not be fulfilled using a freelist slot.  Check
  ** to see if defragmentation is necessary.
  */
  testcase( gap+2+nByte==top );
  if( gap+2+nByte>top ){
    assert( pPage->nCell>0 || CORRUPT_DB );
    assert( pPage->nFree>=0 );
    rc = defragmentPage(pPage, MIN(4, pPage->nFree - (2+nByte)));
    if( rc ) return rc;
    top = get2byteNotZero(&data[hdr+5]);
    assert( gap+2+nByte<=top );
  }


  /* Allocate memory from the gap in between the cell pointer array
  ** and the cell content area.  The btreeComputeFreeSpace() call has already
  ** validated the freelist.  Given that the freelist is valid, there
  ** is no way that the allocation can extend off the end of the page.
  ** The assert() below verifies the previous sentence.
  */
  top -= nByte;
  put2byte(&data[hdr+5], top);
  assert( top+nByte <= (int)pPage->pBt->usableSize );
  *pIdx = top;
  return SQLITE_OK;
}

/*
** Return a section of the pPage->aData to the freelist.
** The first byte of the new free block is pPage->aData[iStart]
** and the size of the block is iSize bytes.
**
** Adjacent freeblocks are coalesced.
**
** Even though the freeblock list was checked by btreeComputeFreeSpace(),
** that routine will not detect overlap between cells or freeblocks.  Nor
** does it detect cells or freeblocks that encrouch into the reserved bytes
** at the end of the page.  So do additional corruption checks inside this
** routine and return SQLITE_CORRUPT if any problems are found.
*/
static int freeSpace(MemPage *pPage, u16 iStart, u16 iSize){
  u16 iPtr;                             /* Address of ptr to next freeblock */

    return SQLITE_CORRUPT_PAGE(pPage);
  }
  pPage->max1bytePayload = pBt->max1bytePayload;
  return SQLITE_OK;
}

/*
** Compute the amount of freespace on the page.  In other words, fill
** in the pPage->nFree field.





*/
static int btreeComputeFreeSpace(MemPage *pPage){
  int pc;            /* Address of a freeblock within pPage->aData[] */
  u8 hdr;            /* Offset to beginning of page header */
  u8 *data;          /* Equal to pPage->aData */

  int usableSize;    /* Amount of usable space on each page */

  int nFree;         /* Number of unused bytes on the page */
  int top;           /* First byte of the cell content area */
  int iCellFirst;    /* First allowable cell or freeblock offset */
  int iCellLast;     /* Last possible cell or freeblock offset */

  assert( pPage->pBt!=0 );
  assert( pPage->pBt->db!=0 );
  assert( sqlite3_mutex_held(pPage->pBt->mutex) );
  assert( pPage->pgno==sqlite3PagerPagenumber(pPage->pDbPage) );
  assert( pPage == sqlite3PagerGetExtra(pPage->pDbPage) );
  assert( pPage->aData == sqlite3PagerGetData(pPage->pDbPage) );
  assert( pPage->isInit==1 );
  assert( pPage->nFree<0 );

  usableSize = pPage->pBt->usableSize;
  hdr = pPage->hdrOffset;
  data = pPage->aData;













  /* EVIDENCE-OF: R-58015-48175 The two-byte integer at offset 5 designates
  ** the start of the cell content area. A zero value for this integer is
  ** interpreted as 65536. */
  top = get2byteNotZero(&data[hdr+5]);













  iCellFirst = hdr + 8 + pPage->childPtrSize + 2*pPage->nCell;








  iCellLast = usableSize - 4;





















  /* Compute the total free space on the page
  ** EVIDENCE-OF: R-23588-34450 The two-byte integer at offset 1 gives the
  ** start of the first freeblock on the page, or is zero if there are no
  ** freeblocks. */
  pc = get2byte(&data[hdr+1]);
  nFree = data[hdr+7] + top;  /* Init nFree to non-freeblock free space */

  ** serves to verify that the offset to the start of the cell-content
  ** area, according to the page header, lies within the page.
  */
  if( nFree>usableSize ){
    return SQLITE_CORRUPT_PAGE(pPage);
  }
  pPage->nFree = (u16)(nFree - iCellFirst);
  return SQLITE_OK;
}

/*
** Do additional sanity check after btreeInitPage() if
** PRAGMA cell_size_check=ON 
*/
static SQLITE_NOINLINE int btreeCellSizeCheck(MemPage *pPage){
  int iCellFirst;    /* First allowable cell or freeblock offset */
  int iCellLast;     /* Last possible cell or freeblock offset */
  int i;             /* Index into the cell pointer array */
  int sz;            /* Size of a cell */
  int pc;            /* Address of a freeblock within pPage->aData[] */
  u8 *data;          /* Equal to pPage->aData */
  int usableSize;    /* Maximum usable space on the page */
  int cellOffset;    /* Start of cell content area */

  iCellFirst = pPage->cellOffset + 2*pPage->nCell;
  usableSize = pPage->pBt->usableSize;
  iCellLast = usableSize - 4;
  data = pPage->aData;
  cellOffset = pPage->cellOffset;
  if( !pPage->leaf ) iCellLast--;
  for(i=0; i<pPage->nCell; i++){
    pc = get2byteAligned(&data[cellOffset+i*2]);
    testcase( pc==iCellFirst );
    testcase( pc==iCellLast );
    if( pc<iCellFirst || pc>iCellLast ){
      return SQLITE_CORRUPT_PAGE(pPage);
    }
    sz = pPage->xCellSize(pPage, &data[pc]);
    testcase( pc+sz==usableSize );
    if( pc+sz>usableSize ){
      return SQLITE_CORRUPT_PAGE(pPage);
    }
  }
  return SQLITE_OK;
}

/*
** Initialize the auxiliary information for a disk block.
**
** Return SQLITE_OK on success.  If we see that the page does
** not contain a well-formed database page, then return 
** SQLITE_CORRUPT.  Note that a return of SQLITE_OK does not
** guarantee that the page is well-formed.  It only shows that
** we failed to detect any corruption.
*/
static int btreeInitPage(MemPage *pPage){
  u8 *data;          /* Equal to pPage->aData */
  BtShared *pBt;        /* The main btree structure */

  assert( pPage->pBt!=0 );
  assert( pPage->pBt->db!=0 );
  assert( sqlite3_mutex_held(pPage->pBt->mutex) );
  assert( pPage->pgno==sqlite3PagerPagenumber(pPage->pDbPage) );
  assert( pPage == sqlite3PagerGetExtra(pPage->pDbPage) );
  assert( pPage->aData == sqlite3PagerGetData(pPage->pDbPage) );
  assert( pPage->isInit==0 );

  pBt = pPage->pBt;
  data = pPage->aData + pPage->hdrOffset;
  /* EVIDENCE-OF: R-28594-02890 The one-byte flag at offset 0 indicating
  ** the b-tree page type. */
  if( decodeFlags(pPage, data[0]) ){
    return SQLITE_CORRUPT_PAGE(pPage);
  }
  assert( pBt->pageSize>=512 && pBt->pageSize<=65536 );
  pPage->maskPage = (u16)(pBt->pageSize - 1);
  pPage->nOverflow = 0;
  pPage->cellOffset = pPage->hdrOffset + 8 + pPage->childPtrSize;
  pPage->aCellIdx = data + pPage->childPtrSize + 8;
  pPage->aDataEnd = pPage->aData + pBt->usableSize;
  pPage->aDataOfst = pPage->aData + pPage->childPtrSize;
  /* EVIDENCE-OF: R-37002-32774 The two-byte integer at offset 3 gives the
  ** number of cells on the page. */
  pPage->nCell = get2byte(&data[3]);
  if( pPage->nCell>MX_CELL(pBt) ){
    /* To many cells for a single page.  The page must be corrupt */
    return SQLITE_CORRUPT_PAGE(pPage);
  }
  testcase( pPage->nCell==MX_CELL(pBt) );
  /* EVIDENCE-OF: R-24089-57979 If a page contains no cells (which is only
  ** possible for a root page of a table that contains no rows) then the
  ** offset to the cell content area will equal the page size minus the
  ** bytes of reserved space. */
  assert( pPage->nCell>0
       || get2byteNotZero(&data[5])==(int)pBt->usableSize
       || CORRUPT_DB );
  pPage->nFree = -1;  /* Indicate that this value is yet uncomputed */
  pPage->isInit = 1;
  if( pBt->db->flags & SQLITE_CellSizeCk ){
    return btreeCellSizeCheck(pPage);
  }
  return SQLITE_OK;
}

/*
** Set up a raw page so that it looks like a database page holding
** no entries.
*/

  assert( sqlite3_mutex_held(pBt->mutex) );
  assert( pCur==0 || ppPage==&pCur->pPage );
  assert( pCur==0 || bReadOnly==pCur->curPagerFlags );
  assert( pCur==0 || pCur->iPage>0 );

  if( pgno>btreePagecount(pBt) ){
    rc = SQLITE_CORRUPT_BKPT;
    goto getAndInitPage_error1;
  }
  rc = sqlite3PagerGet(pBt->pPager, pgno, (DbPage**)&pDbPage, bReadOnly);
  if( rc ){
    goto getAndInitPage_error1;
  }
  *ppPage = (MemPage*)sqlite3PagerGetExtra(pDbPage);
  if( (*ppPage)->isInit==0 ){
    btreePageFromDbPage(pDbPage, pgno, pBt);
    rc = btreeInitPage(*ppPage);
    if( rc!=SQLITE_OK ){

      goto getAndInitPage_error2;
    }
  }
  assert( (*ppPage)->pgno==pgno );
  assert( (*ppPage)->aData==sqlite3PagerGetData(pDbPage) );

  /* If obtaining a child page for a cursor, we must verify that the page is
  ** compatible with the root page. */
  if( pCur && ((*ppPage)->nCell<1 || (*ppPage)->intKey!=pCur->curIntKey) ){
    rc = SQLITE_CORRUPT_PGNO(pgno);

    goto getAndInitPage_error2;
  }
  return SQLITE_OK;

getAndInitPage_error2:
  releasePage(*ppPage);
getAndInitPage_error1:
  if( pCur ){
    pCur->iPage--;
    pCur->pPage = pCur->apPage[pCur->iPage];
  }
  testcase( pgno==0 );
  assert( pgno!=0 || rc==SQLITE_CORRUPT );
  return rc;

    assert( pCur->pgnoRoot==0 || pCur->pPage->nCell==0 );
    *pRes = 1;
    rc = SQLITE_OK;
  }
  return rc;
}


















/* Move the cursor to the last entry in the table.  Return SQLITE_OK
** on success.  Set *pRes to 0 if the cursor actually points to something
** or set *pRes to 1 if the table is empty.
*/
SQLITE_PRIVATE int sqlite3BtreeLast(BtCursor *pCur, int *pRes){
  int rc;
 

          pCur->ix = (u16)idx;
          rc = accessPayload(pCur, 0, nCell, (unsigned char*)pCellKey, 0);
          pCur->curFlags &= ~BTCF_ValidOvfl;
          if( rc ){
            sqlite3_free(pCellKey);
            goto moveto_finish;
          }
          c = sqlite3VdbeRecordCompare(nCell, pCellKey, pIdxKey);
          sqlite3_free(pCellKey);
        }
        assert( 
            (pIdxKey->errCode!=SQLITE_CORRUPT || c==0)
         && (pIdxKey->errCode!=SQLITE_NOMEM || pCur->pBtree->db->mallocFailed)
        );
        if( c<0 ){

*/
static int freePage2(BtShared *pBt, MemPage *pMemPage, Pgno iPage){
  MemPage *pTrunk = 0;                /* Free-list trunk page */
  Pgno iTrunk = 0;                    /* Page number of free-list trunk page */ 
  MemPage *pPage1 = pBt->pPage1;      /* Local reference to page 1 */
  MemPage *pPage;                     /* Page being freed. May be NULL. */
  int rc;                             /* Return Code */
  u32 nFree;                          /* Initial number of pages on free-list */

  assert( sqlite3_mutex_held(pBt->mutex) );
  assert( CORRUPT_DB || iPage>1 );
  assert( !pMemPage || pMemPage->pgno==iPage );

  if( iPage<2 || iPage>pBt->nPage ){
    return SQLITE_CORRUPT_BKPT;
  }
  if( pMemPage ){
    pPage = pMemPage;
    sqlite3PagerRef(pPage->pDbPage);
  }else{
    pPage = btreePageLookup(pBt, iPage);
  }

  int hdr;        /* Beginning of the header.  0 most pages.  100 page 1 */

  if( *pRC ) return;
  assert( idx>=0 && idx<pPage->nCell );
  assert( CORRUPT_DB || sz==cellSize(pPage, idx) );
  assert( sqlite3PagerIswriteable(pPage->pDbPage) );
  assert( sqlite3_mutex_held(pPage->pBt->mutex) );
  assert( pPage->nFree>=0 );
  data = pPage->aData;
  ptr = &pPage->aCellIdx[2*idx];
  pc = get2byte(ptr);
  hdr = pPage->hdrOffset;
  testcase( pc==get2byte(&data[hdr+5]) );
  testcase( pc+sz==pPage->pBt->usableSize );
  if( pc+sz > pPage->pBt->usableSize ){

  assert( sqlite3_mutex_held(pPage->pBt->mutex) );
  /* The cell should normally be sized correctly.  However, when moving a
  ** malformed cell from a leaf page to an interior page, if the cell size
  ** wanted to be less than 4 but got rounded up to 4 on the leaf, then size
  ** might be less than 8 (leaf-size + pointer) on the interior node.  Hence
  ** the term after the || in the following assert(). */
  assert( sz==pPage->xCellSize(pPage, pCell) || (sz==8 && iChild>0) );
  assert( pPage->nFree>=0 );
  if( pPage->nOverflow || sz+2>pPage->nFree ){
    if( pTemp ){
      memcpy(pTemp, pCell, sz);
      pCell = pTemp;
    }
    if( iChild ){
      put4byte(pCell, iChild);

    }
    pIns = pPage->aCellIdx + i*2;
    memmove(pIns+2, pIns, 2*(pPage->nCell - i));
    put2byte(pIns, idx);
    pPage->nCell++;
    /* increment the cell count */
    if( (++data[pPage->hdrOffset+4])==0 ) data[pPage->hdrOffset+3]++;
    assert( get2byte(&data[pPage->hdrOffset+3])==pPage->nCell || CORRUPT_DB );
#ifndef SQLITE_OMIT_AUTOVACUUM
    if( pPage->pBt->autoVacuum ){
      /* The cell may contain a pointer to an overflow page. If so, write
      ** the entry for the overflow page into the pointer map.
      */
      ptrmapPutOvflPtr(pPage, pPage, pCell, pRC);
    }

**    ixNx[3] = Number of cells in Child-1 and Child-2 + both divider cells
**    ixNx[4] = Total number of cells.
**
** For a table-btree, the concept is similar, except only apEnd[0]..apEnd[2]
** are used and they point to the leaf pages only, and the ixNx value are:
**
**    ixNx[0] = Number of cells in Child-1.
**    ixNx[1] = Number of cells in Child-1 and Child-2.
**    ixNx[2] = Total number of cells.
**
** Sometimes when deleting, a child page can have zero cells.  In those
** cases, ixNx[] entries with higher indexes, and the corresponding apEnd[]
** entries, shift down.  The end result is that each ixNx[] entry should
** be larger than the previous
*/
typedef struct CellArray CellArray;
struct CellArray {
  int nCell;              /* Number of cells in apCell[] */
  MemPage *pRef;          /* Reference page */
  u8 **apCell;            /* All cells begin balanced */
  u16 *szCell;            /* Local size of all cells in apCell[] */

  }

  /* Add any overflow cells */
  for(i=0; i<pPg->nOverflow; i++){
    int iCell = (iOld + pPg->aiOvfl[i]) - iNew;
    if( iCell>=0 && iCell<nNew ){
      pCellptr = &pPg->aCellIdx[iCell * 2];
      if( nCell>iCell ){
        memmove(&pCellptr[2], pCellptr, (nCell - iCell) * 2);
      }
      nCell++;
      if( pageInsertArray(
            pPg, pBegin, &pData, pCellptr,
            iCell+iNew, 1, pCArray
      ) ) goto editpage_fail;
    }
  }

  MemPage *pNew;                       /* Newly allocated page */
  int rc;                              /* Return Code */
  Pgno pgnoNew;                        /* Page number of pNew */

  assert( sqlite3_mutex_held(pPage->pBt->mutex) );
  assert( sqlite3PagerIswriteable(pParent->pDbPage) );
  assert( pPage->nOverflow==1 );
  
  if( pPage->nCell==0 ) return SQLITE_CORRUPT_BKPT;  /* dbfuzz001.test */
  assert( pPage->nFree>=0 );
  assert( pParent->nFree>=0 );

  /* Allocate a new page. This page will become the right-sibling of 
  ** pPage. Make the parent page writable, so that the new divider cell
  ** may be inserted. If both these operations are successful, proceed.
  */
  rc = allocateBtreePage(pBt, &pNew, &pgnoNew, 0, 0);

    /* Reinitialize page pTo so that the contents of the MemPage structure
    ** match the new data. The initialization of pTo can actually fail under
    ** fairly obscure circumstances, even though it is a copy of initialized 
    ** page pFrom.
    */
    pTo->isInit = 0;
    rc = btreeInitPage(pTo);
    if( rc==SQLITE_OK ) rc = btreeComputeFreeSpace(pTo);
    if( rc!=SQLITE_OK ){
      *pRC = rc;
      return;
    }
  
    /* If this is an auto-vacuum database, update the pointer-map entries
    ** for any b-tree or overflow pages that pTo now contains the pointers to.

  */
  assert( pParent->nOverflow==0 || pParent->nOverflow==1 );
  assert( pParent->nOverflow==0 || pParent->aiOvfl[0]==iParentIdx );

  if( !aOvflSpace ){
    return SQLITE_NOMEM_BKPT;
  }
  assert( pParent->nFree>=0 );

  /* Find the sibling pages to balance. Also locate the cells in pParent 
  ** that divide the siblings. An attempt is made to find NN siblings on 
  ** either side of pPage. More siblings are taken from one side, however, 
  ** if there are fewer than NN siblings on the other side. If pParent
  ** has NB or fewer children then all children of pParent are taken.  
  **

  pgno = get4byte(pRight);
  while( 1 ){
    rc = getAndInitPage(pBt, pgno, &apOld[i], 0, 0);
    if( rc ){
      memset(apOld, 0, (i+1)*sizeof(MemPage*));
      goto balance_cleanup;
    }
    if( apOld[i]->nFree<0 ){
      rc = btreeComputeFreeSpace(apOld[i]);
      if( rc ){
        memset(apOld, 0, (i)*sizeof(MemPage*));
        goto balance_cleanup;
      }
    }
    if( (i--)==0 ) break;

    if( pParent->nOverflow && i+nxDiv==pParent->aiOvfl[0] ){
      apDiv[i] = pParent->apOvfl[0];
      pgno = get4byte(apDiv[i]);
      szNew[i] = pParent->xCellSize(pParent, apDiv[i]);
      pParent->nOverflow = 0;

      }
      dropCell(pParent, i+nxDiv-pParent->nOverflow, szNew[i], &rc);
    }
  }

  /* Make nMaxCells a multiple of 4 in order to preserve 8-byte
  ** alignment */
  nMaxCells = nOld*(MX_CELL(pBt) + ArraySize(pParent->apOvfl));
  nMaxCells = (nMaxCells + 3)&~3;

  /*
  ** Allocate space for memory structures
  */
  szScratch =
       nMaxCells*sizeof(u8*)                       /* b.apCell */
     + nMaxCells*sizeof(u16)                       /* b.szCell */
     + pBt->pageSize;                              /* aSpace1 */

  assert( szScratch<=7*(int)pBt->pageSize );
  b.apCell = sqlite3StackAllocRaw(0, szScratch );
  if( b.apCell==0 ){
    rc = SQLITE_NOMEM_BKPT;
    goto balance_cleanup;
  }
  b.szCell = (u16*)&b.apCell[nMaxCells];
  aSpace1 = (u8*)&b.szCell[nMaxCells];

  ** 
  */
  usableSpace = pBt->usableSize - 12 + leafCorrection;
  for(i=k=0; i<nOld; i++, k++){
    MemPage *p = apOld[i];
    b.apEnd[k] = p->aDataEnd;
    b.ixNx[k] = cntOld[i];
    if( k && b.ixNx[k]==b.ixNx[k-1] ){
      k--;  /* Omit b.ixNx[] entry for child pages with no cells */
    }
    if( !leafData ){
      k++;
      b.apEnd[k] = pParent->aDataEnd;
      b.ixNx[k] = cntOld[i]+1;
    }
    assert( p->nFree>=0 );
    szNew[i] = usableSpace - p->nFree;
    for(j=0; j<p->nOverflow; j++){
      szNew[i] += 2 + p->xCellSize(p, p->apOvfl[j]);
    }
    cntNew[i] = cntOld[i];
  }
  k = nOld;

  ** associated with the right-child of each sibling may also need to be 
  ** updated. This happens below, after the sibling pages have been 
  ** populated, not here.
  */
  if( ISAUTOVACUUM ){
    MemPage *pOld;
    MemPage *pNew = pOld = apNew[0];

    int cntOldNext = pNew->nCell + pNew->nOverflow;

    int iNew = 0;
    int iOld = 0;

    for(i=0; i<b.nCell; i++){
      u8 *pCell = b.apCell[i];
      while( i==cntOldNext ){
        iOld++;
        assert( iOld<nNew || iOld<nOld );
        pOld = iOld<nNew ? apNew[iOld] : apOld[iOld];
        cntOldNext += pOld->nCell + pOld->nOverflow + !leafData;

      }
      if( i==cntNew[iNew] ){
        pNew = apNew[++iNew];
        if( !leafData ) continue;
      }

      /* Cell pCell is destined for new sibling page pNew. Originally, it
      ** was either part of sibling page iOld (possibly an overflow cell), 
      ** or else the divider cell to the left of sibling page iOld. So,
      ** if sibling page iOld had the same page number as pNew, and if
      ** pCell really was a part of sibling page iOld (not a divider or
      ** overflow cell), we can skip updating the pointer map entries.  */
      if( iOld>=nNew
       || pNew->pgno!=aPgno[iOld]
       || !SQLITE_WITHIN(pCell,pOld->aData,pOld->aDataEnd)
      ){
        if( !leafCorrection ){
          ptrmapPut(pBt, get4byte(pCell), PTRMAP_BTREE, pNew->pgno, &rc);
        }
        if( cachedCellSize(&b,i)>pNew->minLocal ){
          ptrmapPutOvflPtr(pNew, pOld, pCell, &rc);
        }

    ** by smaller than the child due to the database header, and so all the
    ** free space needs to be up front.
    */
    assert( nNew==1 || CORRUPT_DB );
    rc = defragmentPage(apNew[0], -1);
    testcase( rc!=SQLITE_OK );
    assert( apNew[0]->nFree == 
        (get2byteNotZero(&apNew[0]->aData[5]) - apNew[0]->cellOffset
          - apNew[0]->nCell*2)
      || rc!=SQLITE_OK
    );
    copyNodeContent(apNew[0], pParent, &rc);
    freePage(apNew[0], &rc);
  }else if( ISAUTOVACUUM && !leafCorrection ){
    /* Fix the pointer map entries associated with the right-child of each
    ** sibling page. All other pointer map entries have already been taken

  if( rc ){
    *ppChild = 0;
    releasePage(pChild);
    return rc;
  }
  assert( sqlite3PagerIswriteable(pChild->pDbPage) );
  assert( sqlite3PagerIswriteable(pRoot->pDbPage) );
  assert( pChild->nCell==pRoot->nCell || CORRUPT_DB );

  TRACE(("BALANCE: copy root %d into %d\n", pRoot->pgno, pChild->pgno));

  /* Copy the overflow cells from pRoot to pChild */
  memcpy(pChild->aiOvfl, pRoot->aiOvfl,
         pRoot->nOverflow*sizeof(pRoot->aiOvfl[0]));
  memcpy(pChild->apOvfl, pRoot->apOvfl,

  VVA_ONLY( int balance_quick_called = 0 );
  VVA_ONLY( int balance_deeper_called = 0 );

  do {
    int iPage = pCur->iPage;
    MemPage *pPage = pCur->pPage;

    if( NEVER(pPage->nFree<0) && btreeComputeFreeSpace(pPage) ) break;
    if( iPage==0 ){
      if( pPage->nOverflow ){
        /* The root page of the b-tree is overfull. In this case call the
        ** balance_deeper() function to create a new child for the root-page
        ** and copy the current contents of the root-page to it. The
        ** next iteration of the do-loop will balance the child page.
        */ 

    }else if( pPage->nOverflow==0 && pPage->nFree<=nMin ){
      break;
    }else{
      MemPage * const pParent = pCur->apPage[iPage-1];
      int const iIdx = pCur->aiIdx[iPage-1];

      rc = sqlite3PagerWrite(pParent->pDbPage);
      if( rc==SQLITE_OK && pParent->nFree<0 ){
        rc = btreeComputeFreeSpace(pParent);
      }
      if( rc==SQLITE_OK ){
#ifndef SQLITE_OMIT_QUICKBALANCE
        if( pPage->intKeyLeaf
         && pPage->nOverflow==1
         && pPage->aiOvfl[0]==pPage->nCell
         && pParent->pgno!=1
         && pParent->nCell==iIdx

  }
  assert( pCur->eState==CURSOR_VALID || (pCur->eState==CURSOR_INVALID && loc) );

  pPage = pCur->pPage;
  assert( pPage->intKey || pX->nKey>=0 );
  assert( pPage->leaf || !pPage->intKey );
  if( pPage->nFree<0 ){
    rc = btreeComputeFreeSpace(pPage);
    if( rc ) return rc;
  }

  TRACE(("INSERT: table=%d nkey=%lld ndata=%d page=%d %s\n",
          pCur->pgnoRoot, pX->nKey, pX->nData, pPage->pgno,
          loc==0 ? "overwrite" : "new entry"));
  assert( pPage->isInit );
  newCell = pBt->pTmpSpace;
  assert( newCell!=0 );

  assert( cursorOwnsBtShared(pCur) );
  assert( pBt->inTransaction==TRANS_WRITE );
  assert( (pBt->btsFlags & BTS_READ_ONLY)==0 );
  assert( pCur->curFlags & BTCF_WriteFlag );
  assert( hasSharedCacheTableLock(p, pCur->pgnoRoot, pCur->pKeyInfo!=0, 2) );
  assert( !hasReadConflicts(p, pCur->pgnoRoot) );
  assert( (flags & ~(BTREE_SAVEPOSITION | BTREE_AUXDELETE))==0 );
  if( pCur->eState==CURSOR_REQUIRESEEK ){
    rc = btreeRestoreCursorPosition(pCur);
    if( rc ) return rc;
  }
  assert( pCur->eState==CURSOR_VALID );


  iCellDepth = pCur->iPage;
  iCellIdx = pCur->ix;
  pPage = pCur->pPage;
  pCell = findCell(pPage, iCellIdx);
  if( pPage->nFree<0 && btreeComputeFreeSpace(pPage) ) return SQLITE_CORRUPT;

  /* If the bPreserve flag is set to true, then the cursor position must
  ** be preserved following this delete operation. If the current delete
  ** will cause a b-tree rebalance, then this is done by saving the cursor
  ** key and leaving the cursor in CURSOR_REQUIRESEEK state before 
  ** returning. 
  **

  ** node to replace the deleted cell.  */
  if( !pPage->leaf ){
    MemPage *pLeaf = pCur->pPage;
    int nCell;
    Pgno n;
    unsigned char *pTmp;

    if( pLeaf->nFree<0 ){
      rc = btreeComputeFreeSpace(pLeaf);
      if( rc ) return rc;
    }
    if( iCellDepth<pCur->iPage-1 ){
      n = pCur->apPage[iCellDepth+1]->pgno;
    }else{
      n = pCur->pPage->pgno;
    }
    pCell = findCell(pLeaf, pLeaf->nCell-1);
    if( pCell<&pLeaf->aData[4] ) return SQLITE_CORRUPT_BKPT;

  int rc;
  MemPage *pPage = 0;
  BtShared *pBt = p->pBt;

  assert( sqlite3BtreeHoldsMutex(p) );
  assert( p->inTrans==TRANS_WRITE );
  assert( iTable>=2 );
  if( iTable>btreePagecount(pBt) ){
    return SQLITE_CORRUPT_BKPT;
  }

  rc = btreeGetPage(pBt, (Pgno)iTable, &pPage, 0);
  if( rc ) return rc;
  rc = sqlite3BtreeClearTable(p, iTable, 0);
  if( rc ){
    releasePage(pPage);
    return rc;

** Check the integrity of the freelist or of an overflow page list.
** Verify that the number of pages on the list is N.
*/
static void checkList(
  IntegrityCk *pCheck,  /* Integrity checking context */
  int isFreeList,       /* True for a freelist.  False for overflow page list */
  int iPage,            /* Page number for first page in the list */
  u32 N                 /* Expected number of pages in the list */
){
  int i;
  u32 expected = N;
  int nErrAtStart = pCheck->nErr;
  while( iPage!=0 && pCheck->mxErr ){
    DbPage *pOvflPage;
    unsigned char *pOvflData;
    if( checkRef(pCheck, iPage) ) break;
    N--;
    if( sqlite3PagerGet(pCheck->pPager, (Pgno)iPage, &pOvflPage, 0) ){

  pPage->isInit = 0;
  if( (rc = btreeInitPage(pPage))!=0 ){
    assert( rc==SQLITE_CORRUPT );  /* The only possible error from InitPage */
    checkAppendMsg(pCheck,
                   "btreeInitPage() returns error code %d", rc);
    goto end_of_check;
  }
  if( (rc = btreeComputeFreeSpace(pPage))!=0 ){
    assert( rc==SQLITE_CORRUPT );
    checkAppendMsg(pCheck, "free space corruption", rc);
    goto end_of_check;
  }
  data = pPage->aData;
  hdr = pPage->hdrOffset;

  /* Set up for cell analysis */
  pCheck->zPfx = "On tree page %d cell %d: ";
  contentOffset = get2byteNotZero(&data[hdr+5]);
  assert( contentOffset<=usableSize );  /* Enforced by btreeInitPage() */

      }
      maxKey = info.nKey;
      keyCanBeEqual = 0;     /* Only the first key on the page may ==maxKey */
    }

    /* Check the content overflow list */
    if( info.nPayload>info.nLocal ){
      u32 nPage;       /* Number of pages on the overflow chain */
      Pgno pgnoOvfl;   /* First page of the overflow chain */
      assert( pc + info.nSize - 4 <= usableSize );
      nPage = (info.nPayload - info.nLocal + usableSize - 5)/(usableSize - 4);
      pgnoOvfl = get4byte(&pCell[info.nSize - 4]);
#ifndef SQLITE_OMIT_AUTOVACUUM
      if( pBt->autoVacuum ){
        checkPtrmap(pCheck, pgnoOvfl, PTRMAP_OVERFLOW1, iPage);

    ** EVIDENCE-OF: R-20690-50594 The second field of the b-tree page header
    ** is the offset of the first freeblock, or zero if there are no
    ** freeblocks on the page. 
    */
    i = get2byte(&data[hdr+1]);
    while( i>0 ){
      int size, j;
      assert( (u32)i<=usableSize-4 ); /* Enforced by btreeComputeFreeSpace() */
      size = get2byte(&data[i+2]);
      assert( (u32)(i+size)<=usableSize ); /* due to btreeComputeFreeSpace() */
      btreeHeapInsert(heap, (((u32)i)<<16)|(i+size-1));
      /* EVIDENCE-OF: R-58208-19414 The first 2 bytes of a freeblock are a
      ** big-endian integer which is the offset in the b-tree page of the next
      ** freeblock in the chain, or zero if the freeblock is the last on the
      ** chain. */
      j = get2byte(&data[i]);
      /* EVIDENCE-OF: R-06866-39125 Freeblocks are always connected in order of
      ** increasing offset. */
      assert( j==0 || j>i+size );     /* Enforced by btreeComputeFreeSpace() */
      assert( (u32)j<=usableSize-4 ); /* Enforced by btreeComputeFreeSpace() */
      i = j;
    }
    /* Analyze the min-heap looking for overlap between cells and/or 
    ** freeblocks, and counting the number of untracked bytes in nFrag.
    ** 
    ** Each min-heap entry is of the form:    (start_address<<16)|end_address.
    ** There is an implied first entry the covers the page header, the cell

      /* This is a pointer type.  There may be a flag to indicate what to
      ** do with the pointer. */
      assert( ((p->flags&MEM_Dyn)!=0 ? 1 : 0) +
              ((p->flags&MEM_Ephem)!=0 ? 1 : 0) +
              ((p->flags&MEM_Static)!=0 ? 1 : 0) <= 1 );

      /* No other bits set */
      assert( (p->flags & ~(MEM_Null|MEM_Term|MEM_Subtype|MEM_FromBind
                           |MEM_Dyn|MEM_Ephem|MEM_Static))==0 );
    }else{
      /* A pure NULL might have other flags, such as MEM_Static, MEM_Dyn,
      ** MEM_Ephem, MEM_Cleared, or MEM_Subtype */
    }
  }else{
    /* The MEM_Cleared bit is only allowed on NULLs */

  assert(rc==SQLITE_OK    || pMem->enc!=desiredEnc);
  assert(rc==SQLITE_NOMEM || pMem->enc==desiredEnc);
  return rc;
#endif
}

/*
** Make sure pMem->z points to a writable allocation of at least n bytes.

**
** If the bPreserve argument is true, then copy of the content of
** pMem->z into the new allocation.  pMem must be either a string or
** blob if bPreserve is true.  If bPreserve is false, any prior content
** in pMem->z is discarded.
*/
SQLITE_PRIVATE SQLITE_NOINLINE int sqlite3VdbeMemGrow(Mem *pMem, int n, int bPreserve){
  assert( sqlite3VdbeCheckMemInvariants(pMem) );
  assert( !sqlite3VdbeMemIsRowSet(pMem) );
  testcase( pMem->db==0 );

  /* If the bPreserve flag is set to true, then the memory cell must already
  ** contain a valid string or blob value.  */
  assert( bPreserve==0 || pMem->flags&(MEM_Blob|MEM_Str) );
  testcase( bPreserve && pMem->z==0 );

  assert( pMem->szMalloc==0
       || pMem->szMalloc==sqlite3DbMallocSize(pMem->db, pMem->zMalloc) );

  if( pMem->szMalloc>0 && bPreserve && pMem->z==pMem->zMalloc ){
    pMem->z = pMem->zMalloc = sqlite3DbReallocOrFree(pMem->db, pMem->z, n);
    bPreserve = 0;
  }else{
    if( pMem->szMalloc>0 ) sqlite3DbFreeNN(pMem->db, pMem->zMalloc);
    pMem->zMalloc = sqlite3DbMallocRaw(pMem->db, n);
  }

** If the given Mem* has a zero-filled tail, turn it into an ordinary
** blob stored in dynamically allocated space.
*/
#ifndef SQLITE_OMIT_INCRBLOB
SQLITE_PRIVATE int sqlite3VdbeMemExpandBlob(Mem *pMem){
  int nByte;
  assert( pMem->flags & MEM_Zero );
  assert( (pMem->flags&MEM_Blob)!=0 || MemNullNochng(pMem) );
  testcase( sqlite3_value_nochange(pMem) );
  assert( !sqlite3VdbeMemIsRowSet(pMem) );
  assert( pMem->db==0 || sqlite3_mutex_held(pMem->db->mutex) );

  /* Set nByte to the number of bytes required to store the expanded blob. */
  nByte = pMem->n + pMem->u.nZero;
  if( nByte<=0 ){
    if( (pMem->flags & MEM_Blob)==0 ) return SQLITE_OK;
    nByte = 1;
  }
  if( sqlite3VdbeMemGrow(pMem, nByte, 1) ){
    return SQLITE_NOMEM_BKPT;
  }

  memset(&pMem->z[pMem->n], 0, pMem->u.nZero);

    iLimit = SQLITE_MAX_LENGTH;
  }
  flags = (enc==0?MEM_Blob:MEM_Str);
  if( nByte<0 ){
    assert( enc!=0 );
    if( enc==SQLITE_UTF8 ){
      nByte = 0x7fffffff & (int)strlen(z);

    }else{
      for(nByte=0; nByte<=iLimit && (z[nByte] | z[nByte+1]); nByte+=2){}
    }
    flags |= MEM_Term;
  }

  /* The following block sets the new values of Mem.z and Mem.xDel. It
  ** also sets a flag in local variable "flags" to indicate the memory
  ** management (one of MEM_Dyn or MEM_Static).
  */
  if( xDel==SQLITE_TRANSIENT ){
    u32 nAlloc = nByte;
    if( flags&MEM_Term ){
      nAlloc += (enc==SQLITE_UTF8?1:2);
    }
    if( nByte>iLimit ){
      return sqlite3ErrorToParser(pMem->db, SQLITE_TOOBIG);
    }
    testcase( nAlloc==0 );
    testcase( nAlloc==31 );
    testcase( nAlloc==32 );
    if( sqlite3VdbeMemClearAndResize(pMem, (int)MAX(nAlloc,32)) ){
      return SQLITE_NOMEM_BKPT;
    }
    memcpy(pMem->z, z, nAlloc);




  }else{
    sqlite3VdbeMemRelease(pMem);
    pMem->z = (char *)z;
    if( xDel==SQLITE_DYNAMIC ){
      pMem->zMalloc = pMem->z;
      pMem->szMalloc = sqlite3DbMallocSize(pMem->db, pMem->zMalloc);
    }else{
      pMem->xDel = xDel;
      flags |= ((xDel==SQLITE_STATIC)?MEM_Static:MEM_Dyn);
    }
  }

  pMem->n = nByte;
  pMem->flags = flags;
  pMem->enc = (enc==0 ? SQLITE_UTF8 : enc);

#ifndef SQLITE_OMIT_UTF16

  ** more frequent reallocs and hence provide more opportunities for 
  ** simulated OOM faults.  SQLITE_TEST_REALLOC_STRESS is generally used
  ** during testing only.  With SQLITE_TEST_REALLOC_STRESS grow the op array
  ** by the minimum* amount required until the size reaches 512.  Normal
  ** operation (without SQLITE_TEST_REALLOC_STRESS) is to double the current
  ** size of the op array or add 1KB of space, whichever is smaller. */
#ifdef SQLITE_TEST_REALLOC_STRESS
  sqlite3_int64 nNew = (v->nOpAlloc>=512 ? 2*(sqlite3_int64)v->nOpAlloc
                        : (sqlite3_int64)v->nOpAlloc+nOp);
#else
  sqlite3_int64 nNew = (v->nOpAlloc ? 2*(sqlite3_int64)v->nOpAlloc
                        : (sqlite3_int64)(1024/sizeof(Op)));
  UNUSED_PARAMETER(nOp);
#endif

  /* Ensure that the size of a VDBE does not grow too large */
  if( nNew > p->db->aLimit[SQLITE_LIMIT_VDBE_OP] ){
    sqlite3OomFault(p->db);
    return SQLITE_NOMEM;

  memset(&sIter, 0, sizeof(sIter));
  sIter.v = v;

  while( (pOp = opIterNext(&sIter))!=0 ){
    int opcode = pOp->opcode;
    if( opcode==OP_Destroy || opcode==OP_VUpdate || opcode==OP_VRename 
     || opcode==OP_VDestroy
     || (opcode==OP_Function0 && pOp->p4.pFunc->funcFlags&SQLITE_FUNC_INTERNAL)
     || ((opcode==OP_Halt || opcode==OP_HaltIfNull) 
      && ((pOp->p1)!=SQLITE_OK && pOp->p2==OE_Abort))
    ){
      hasAbort = 1;
      break;
    }
    if( opcode==OP_CreateBtree && pOp->p3==BTREE_INTKEY ) hasCreateTable = 1;

  Vdbe *p,                        /* VM to add scanstatus() to */
  int addrExplain,                /* Address of OP_Explain (or 0) */
  int addrLoop,                   /* Address of loop counter */ 
  int addrVisit,                  /* Address of rows visited counter */
  LogEst nEst,                    /* Estimated number of output rows */
  const char *zName               /* Name of table or index being scanned */
){
  sqlite3_int64 nByte = (p->nScan+1) * sizeof(ScanStatus);
  ScanStatus *aNew;
  aNew = (ScanStatus*)sqlite3DbRealloc(p->db, p->aScan, nByte);
  if( aNew ){
    ScanStatus *pNew = &aNew[p->nScan++];
    pNew->addrExplain = addrExplain;
    pNew->addrLoop = addrLoop;
    pNew->addrVisit = addrVisit;

#endif /* !SQLITE_OMIT_TRACE && SQLITE_ENABLE_IOTRACE */

/* An instance of this object describes bulk memory available for use
** by subcomponents of a prepared statement.  Space is allocated out
** of a ReusableSpace object by the allocSpace() routine below.
*/
struct ReusableSpace {
  u8 *pSpace;            /* Available memory */
  sqlite3_int64 nFree;   /* Bytes of available memory */
  sqlite3_int64 nNeeded; /* Total bytes that could not be allocated */
};

/* Try to allocate nByte bytes of 8-byte aligned bulk memory for pBuf
** from the ReusableSpace object.  Return a pointer to the allocated
** memory on success.  If insufficient memory is available in the
** ReusableSpace object, increase the ReusableSpace.nNeeded
** value by the amount needed and return NULL.
**
** If pBuf is not initially NULL, that means that the memory has already
** been allocated by a prior call to this routine, so just return a copy
** of pBuf and leave ReusableSpace unchanged.
**
** This allocator is employed to repurpose unused slots at the end of the
** opcode array of prepared state for other memory needs of the prepared
** statement.
*/
static void *allocSpace(
  struct ReusableSpace *p,  /* Bulk memory available for allocation */
  void *pBuf,               /* Pointer to a prior allocation */
  sqlite3_int64 nByte       /* Bytes of memory needed */
){
  assert( EIGHT_BYTE_ALIGNMENT(p->pSpace) );
  if( pBuf==0 ){
    nByte = ROUND8(nByte);
    if( nByte <= p->nFree ){
      p->nFree -= nByte;
      pBuf = &p->pSpace[p->nFree];

  sqlite3_int64 iElapse;
  assert( p->startTime>0 );
  assert( (db->mTrace & (SQLITE_TRACE_PROFILE|SQLITE_TRACE_XPROFILE))!=0 );
  assert( db->init.busy==0 );
  assert( p->zSql!=0 );
  sqlite3OsCurrentTimeInt64(db->pVfs, &iNow);
  iElapse = (iNow - p->startTime)*1000000;
#ifndef SQLITE_OMIT_DEPRECATED
  if( db->xProfile ){
    db->xProfile(db->pProfileArg, p->zSql, iElapse);
  }
#endif
  if( db->mTrace & SQLITE_TRACE_PROFILE ){
    db->xTrace(SQLITE_TRACE_PROFILE, db->pTraceArg, p, (void*)&iElapse);
  }

  return aType[pVal->flags&MEM_AffMask];
}

/* Return true if a parameter to xUpdate represents an unchanged column */
SQLITE_API int sqlite3_value_nochange(sqlite3_value *pVal){
  return (pVal->flags&(MEM_Null|MEM_Zero))==(MEM_Null|MEM_Zero);
}

/* Return true if a parameter value originated from an sqlite3_bind() */
SQLITE_API int sqlite3_value_frombind(sqlite3_value *pVal){
  return (pVal->flags&MEM_FromBind)!=0;
}

/* Make a copy of an sqlite3_value object
*/
SQLITE_API sqlite3_value *sqlite3_value_dup(const sqlite3_value *pOrig){
  sqlite3_value *pNew;
  if( pOrig==0 ) return 0;
  pNew = sqlite3_malloc( sizeof(*pNew) );

**    3      The name of the table that the column derives from
**    4      The name of the table column that the result column derives from
**
** If the result is not a simple column reference (if it is an expression
** or a constant) then useTypes 2, 3, and 4 return NULL.
*/
static const void *columnName(
  sqlite3_stmt *pStmt,     /* The statement */
  int N,                   /* Which column to get the name for */
  int useUtf16,            /* True to return the name as UTF16 */
  int useType              /* What type of name */
){
  const void *ret;
  Vdbe *p;
  int n;
  sqlite3 *db;
#ifdef SQLITE_ENABLE_API_ARMOR
  if( pStmt==0 ){
    (void)SQLITE_MISUSE_BKPT;
    return 0;
  }
#endif
  ret = 0;
  p = (Vdbe *)pStmt;
  db = p->db;
  assert( db!=0 );
  n = sqlite3_column_count(pStmt);
  if( N<n && N>=0 ){
    N += useType*n;
    sqlite3_mutex_enter(db->mutex);
    assert( db->mallocFailed==0 );
#ifndef SQLITE_OMIT_UTF16
    if( useUtf16 ){
      ret = sqlite3_value_text16((sqlite3_value*)&p->aColName[N]);
    }else
#endif
    {
      ret = sqlite3_value_text((sqlite3_value*)&p->aColName[N]);
    }
    /* A malloc may have failed inside of the _text() call. If this
    ** is the case, clear the mallocFailed flag and return NULL.
    */
    if( db->mallocFailed ){
      sqlite3OomClear(db);
      ret = 0;
    }
    sqlite3_mutex_leave(db->mutex);
  }
  return ret;
}

/*
** Return the name of the Nth column of the result set returned by SQL
** statement pStmt.
*/
SQLITE_API const char *sqlite3_column_name(sqlite3_stmt *pStmt, int N){
  return columnName(pStmt, N, 0, COLNAME_NAME);

}
#ifndef SQLITE_OMIT_UTF16
SQLITE_API const void *sqlite3_column_name16(sqlite3_stmt *pStmt, int N){
  return columnName(pStmt, N, 1, COLNAME_NAME);

}
#endif

/*
** Constraint:  If you have ENABLE_COLUMN_METADATA then you must
** not define OMIT_DECLTYPE.
*/
#if defined(SQLITE_OMIT_DECLTYPE) && defined(SQLITE_ENABLE_COLUMN_METADATA)
# error "Must not define both SQLITE_OMIT_DECLTYPE \
         and SQLITE_ENABLE_COLUMN_METADATA"
#endif

#ifndef SQLITE_OMIT_DECLTYPE
/*
** Return the column declaration type (if applicable) of the 'i'th column
** of the result set of SQL statement pStmt.
*/
SQLITE_API const char *sqlite3_column_decltype(sqlite3_stmt *pStmt, int N){
  return columnName(pStmt, N, 0, COLNAME_DECLTYPE);

}
#ifndef SQLITE_OMIT_UTF16
SQLITE_API const void *sqlite3_column_decltype16(sqlite3_stmt *pStmt, int N){
  return columnName(pStmt, N, 1, COLNAME_DECLTYPE);

}
#endif /* SQLITE_OMIT_UTF16 */
#endif /* SQLITE_OMIT_DECLTYPE */

#ifdef SQLITE_ENABLE_COLUMN_METADATA
/*
** Return the name of the database from which a result column derives.
** NULL is returned if the result column is an expression or constant or
** anything else which is not an unambiguous reference to a database column.
*/
SQLITE_API const char *sqlite3_column_database_name(sqlite3_stmt *pStmt, int N){
  return columnName(pStmt, N, 0, COLNAME_DATABASE);

}
#ifndef SQLITE_OMIT_UTF16
SQLITE_API const void *sqlite3_column_database_name16(sqlite3_stmt *pStmt, int N){
  return columnName(pStmt, N, 1, COLNAME_DATABASE);

}
#endif /* SQLITE_OMIT_UTF16 */

/*
** Return the name of the table from which a result column derives.
** NULL is returned if the result column is an expression or constant or
** anything else which is not an unambiguous reference to a database column.
*/
SQLITE_API const char *sqlite3_column_table_name(sqlite3_stmt *pStmt, int N){
  return columnName(pStmt, N, 0, COLNAME_TABLE);

}
#ifndef SQLITE_OMIT_UTF16
SQLITE_API const void *sqlite3_column_table_name16(sqlite3_stmt *pStmt, int N){
  return columnName(pStmt, N, 1, COLNAME_TABLE);

}
#endif /* SQLITE_OMIT_UTF16 */

/*
** Return the name of the table column from which a result column derives.
** NULL is returned if the result column is an expression or constant or
** anything else which is not an unambiguous reference to a database column.
*/
SQLITE_API const char *sqlite3_column_origin_name(sqlite3_stmt *pStmt, int N){
  return columnName(pStmt, N, 0, COLNAME_COLUMN);

}
#ifndef SQLITE_OMIT_UTF16
SQLITE_API const void *sqlite3_column_origin_name16(sqlite3_stmt *pStmt, int N){
  return columnName(pStmt, N, 1, COLNAME_COLUMN);

}
#endif /* SQLITE_OMIT_UTF16 */
#endif /* SQLITE_ENABLE_COLUMN_METADATA */


/******************************* sqlite3_bind_  ***************************
** 

/*
** Return true if the prepared statement is guaranteed to not modify the
** database.
*/
SQLITE_API int sqlite3_stmt_readonly(sqlite3_stmt *pStmt){
  return pStmt ? ((Vdbe*)pStmt)->readOnly : 1;
}

/*
** Return 1 if the statement is an EXPLAIN and return 2 if the
** statement is an EXPLAIN QUERY PLAN
*/
SQLITE_API int sqlite3_stmt_isexplain(sqlite3_stmt *pStmt){
  return pStmt ? ((Vdbe*)pStmt)->explain : 0;
}

/*
** Return true if the prepared statement is in need of being reset.
*/
SQLITE_API int sqlite3_stmt_busy(sqlite3_stmt *pStmt){
  Vdbe *v = (Vdbe*)pStmt;
  return v!=0 && v->magic==VDBE_MAGIC_RUN && v->pc>=0;

#endif

/*
** Invoke the VDBE coverage callback, if that callback is defined.  This
** feature is used for test suite validation only and does not appear an
** production builds.
**
** M is the type of branch.  I is the direction taken for this instance of
** the branch.
**
**   M: 2 - two-way branch (I=0: fall-thru   1: jump                )
**      3 - two-way + NULL (I=0: fall-thru   1: jump      2: NULL   )
**      4 - OP_Jump        (I=0: jump p1     1: jump p2   2: jump p3)
**
** In other words, if M is 2, then I is either 0 (for fall-through) or
** 1 (for when the branch is taken).  If M is 3, the I is 0 for an
** ordinary fall-through, I is 1 if the branch was taken, and I is 2 
** if the result of comparison is NULL.  For M=3, I=2 the jump may or
** may not be taken, depending on the SQLITE_JUMPIFNULL flags in p5.
** When M is 4, that means that an OP_Jump is being run.  I is 0, 1, or 2
** depending on if the operands are less than, equal, or greater than.

**
** iSrcLine is the source code line (from the __LINE__ macro) that
** generated the VDBE instruction combined with flag bits.  The source
** code line number is in the lower 24 bits of iSrcLine and the upper
** 8 bytes are flags.  The lower three bits of the flags indicate
** values for I that should never occur.  For example, if the branch is
** always taken, the flags should be 0x05 since the fall-through and
** alternate branch are never taken.  If a branch is never taken then
** flags should be 0x06 since only the fall-through approach is allowed.
**
** Bit 0x08 of the flags indicates an OP_Jump opcode that is only
** interested in equal or not-equal.  In other words, I==0 and I==2
** should be treated as equivalent
**
** Since only a line number is retained, not the filename, this macro
** only works for amalgamation builds.  But that is ok, since these macros
** should be no-ops except for special builds used to measure test coverage.
*/
#if !defined(SQLITE_VDBE_COVERAGE)
# define VdbeBranchTaken(I,M)

    /* The upper 8 bits of iSrcLine are flags.  The lower three bits of
    ** the flags indicate directions that the branch can never go.  If
    ** a branch really does go in one of those directions, assert right
    ** away. */
    mNever = iSrcLine >> 24;
    assert( (I & mNever)==0 );
    if( sqlite3GlobalConfig.xVdbeBranch==0 ) return;  /*NO_TEST*/
    /* Invoke the branch coverage callback with three arguments:
    **    iSrcLine - the line number of the VdbeCoverage() macro, with
    **               flags removed.
    **    I        - Mask of bits 0x07 indicating which cases are are
    **               fulfilled by this instance of the jump.  0x01 means
    **               fall-thru, 0x02 means taken, 0x04 means NULL.  Any
    **               impossible cases (ex: if the comparison is never NULL)
    **               are filled in automatically so that the coverage
    **               measurement logic does not flag those impossible cases
    **               as missed coverage.
    **    M        - Type of jump.  Same as M argument above
    */
    I |= mNever;
    if( M==2 ) I |= 0x04;
    if( M==4 ){
      I |= 0x08;
      if( (mNever&0x08)!=0 && (I&0x05)!=0) I |= 0x05; /*NO_TEST*/
    }
    sqlite3GlobalConfig.xVdbeBranch(sqlite3GlobalConfig.pVdbeBranchArg,

#ifdef VDBE_PROFILE
  u64 start;                 /* CPU clock count at start of opcode */
#endif
  /*** INSERT STACK UNION HERE ***/

  assert( p->magic==VDBE_MAGIC_RUN );  /* sqlite3_step() verifies this */
  sqlite3VdbeEnter(p);
#ifndef SQLITE_OMIT_PROGRESS_CALLBACK
  if( db->xProgress ){
    u32 iPrior = p->aCounter[SQLITE_STMTSTATUS_VM_STEP];
    assert( 0 < db->nProgressOps );
    nProgressLimit = db->nProgressOps - (iPrior % db->nProgressOps);
  }else{
    nProgressLimit = 0xffffffff;
  }
#endif
  if( p->rc==SQLITE_NOMEM ){
    /* This happens if a malloc() inside a call to sqlite3_column_text() or
    ** sqlite3_column_text16() failed.  */
    goto no_mem;
  }
  assert( p->rc==SQLITE_OK || (p->rc&0xff)==SQLITE_BUSY );
  assert( p->bIsReader || p->readOnly!=0 );
  p->iCurrentTime = 0;
  assert( p->explain==0 );
  p->pResultSet = 0;
  db->busyHandler.nBusy = 0;
  if( db->u1.isInterrupted ) goto abort_due_to_interrupt;
  sqlite3VdbeIOTraceSql(p);









#ifdef SQLITE_DEBUG
  sqlite3BeginBenignMalloc();
  if( p->pc==0
   && (p->db->flags & (SQLITE_VdbeListing|SQLITE_VdbeEQP|SQLITE_VdbeTrace))!=0
  ){
    int i;
    int once = 1;

#ifndef SQLITE_OMIT_PROGRESS_CALLBACK
  /* Call the progress callback if it is configured and the required number
  ** of VDBE ops have been executed (either since this invocation of
  ** sqlite3VdbeExec() or since last time the progress callback was called).
  ** If the progress callback returns non-zero, exit the virtual machine with
  ** a return code SQLITE_ABORT.
  */
  while( nVmStep>=nProgressLimit && db->xProgress!=0 ){
    assert( db->nProgressOps!=0 );
    nProgressLimit += db->nProgressOps;
    if( db->xProgress(db->pProgressArg) ){
      nProgressLimit = 0xffffffff;
      rc = SQLITE_INTERRUPT;
      goto abort_due_to_error;
    }
  }
#endif
  
  break;

  pOp->opcode = OP_String;
  pOp->p1 = sqlite3Strlen30(pOp->p4.z);

#ifndef SQLITE_OMIT_UTF16
  if( encoding!=SQLITE_UTF8 ){
    rc = sqlite3VdbeMemSetStr(pOut, pOp->p4.z, -1, SQLITE_UTF8, SQLITE_STATIC);
    assert( rc==SQLITE_OK || rc==SQLITE_TOOBIG );
    if( rc ) goto too_big;
    if( SQLITE_OK!=sqlite3VdbeChangeEncoding(pOut, encoding) ) goto no_mem;
    assert( pOut->szMalloc>0 && pOut->zMalloc==pOut->z );
    assert( VdbeMemDynamic(pOut)==0 );
    pOut->szMalloc = 0;
    pOut->flags |= MEM_Static;
    if( pOp->p4type==P4_DYNAMIC ){
      sqlite3DbFree(db, pOp->p4.z);
    }
    pOp->p4type = P4_DYNAMIC;
    pOp->p4.z = pOut->z;
    pOp->p1 = pOut->n;
  }

#endif
  if( pOp->p1>db->aLimit[SQLITE_LIMIT_LENGTH] ){
    goto too_big;
  }
  assert( rc==SQLITE_OK );
  /* Fall through to the next case, OP_String */
}

  assert( pOp->p1>0 && pOp->p1<=p->nVar );
  assert( pOp->p4.z==0 || pOp->p4.z==sqlite3VListNumToName(p->pVList,pOp->p1) );
  pVar = &p->aVar[pOp->p1 - 1];
  if( sqlite3VdbeMemTooBig(pVar) ){
    goto too_big;
  }
  pOut = &aMem[pOp->p2];
  if( VdbeMemDynamic(pOut) ) sqlite3VdbeMemSetNull(pOut);
  memcpy(pOut, pVar, MEMCELLSIZE);
  pOut->flags &= ~(MEM_Dyn|MEM_Ephem);
  pOut->flags |= MEM_Static|MEM_FromBind;
  UPDATE_MAX_BLOBSIZE(pOut);
  break;
}

/* Opcode: Move P1 P2 P3 * *
** Synopsis: r[P2@P3]=r[P1@P3]
**

case OP_ResultRow: {
  Mem *pMem;
  int i;
  assert( p->nResColumn==pOp->p2 );
  assert( pOp->p1>0 );
  assert( pOp->p1+pOp->p2<=(p->nMem+1 - p->nCursor)+1 );













  /* If this statement has violated immediate foreign key constraints, do
  ** not return the number of rows modified. And do not RELEASE the statement
  ** transaction. It needs to be rolled back.  */
  if( SQLITE_OK!=(rc = sqlite3VdbeCheckFk(p, 0)) ){
    assert( db->flags&SQLITE_CountRows );
    assert( p->usesStmtJournal );
    goto abort_due_to_error;

** without data loss, then jump immediately to P2, or if P2==0
** raise an SQLITE_MISMATCH exception.
*/
case OP_MustBeInt: {            /* jump, in1 */
  pIn1 = &aMem[pOp->p1];
  if( (pIn1->flags & MEM_Int)==0 ){
    applyAffinity(pIn1, SQLITE_AFF_NUMERIC, encoding);

    if( (pIn1->flags & MEM_Int)==0 ){
      VdbeBranchTaken(1, 2);
      if( pOp->p2==0 ){
        rc = SQLITE_MISMATCH;
        goto abort_due_to_error;
      }else{
        goto jump_to_p2;
      }
    }
  }
  VdbeBranchTaken(0, 2);
  MemSetTypeFlag(pIn1, MEM_Int);
  break;
}

#ifndef SQLITE_OMIT_FLOATING_POINT
/* Opcode: RealAffinity P1 * * * *
**

  if( (flags1 | flags3)&MEM_Null ){
    /* One or both operands are NULL */
    if( pOp->p5 & SQLITE_NULLEQ ){
      /* If SQLITE_NULLEQ is set (which will only happen if the operator is
      ** OP_Eq or OP_Ne) then take the jump or not depending on whether
      ** or not both operands are null.
      */

      assert( (flags1 & MEM_Cleared)==0 );
      assert( (pOp->p5 & SQLITE_JUMPIFNULL)==0 || CORRUPT_DB );
      testcase( (pOp->p5 & SQLITE_JUMPIFNULL)!=0 );
      if( (flags1&flags3&MEM_Null)!=0
       && (flags3&MEM_Cleared)==0
      ){
        res = 0;  /* Operands are equal */
      }else{
        res = ((flags3 & MEM_Null) ? -1 : +1);  /* Operands are not equal */
      }
    }else{
      /* SQLITE_NULLEQ is clear and at least one operand is NULL,
      ** then the result is always NULL.
      ** The jump is taken if the SQLITE_JUMPIFNULL bit is set.
      */
      if( pOp->p5 & SQLITE_STOREP2 ){

      if( (pOp->opcode==OP_Eq)==res2 ) break;
    }
    memAboutToChange(p, pOut);
    MemSetTypeFlag(pOut, MEM_Int);
    pOut->u.i = res2;
    REGISTER_TRACE(pOp->p2, pOut);
  }else{
    VdbeBranchTaken(res2!=0, (pOp->p5 & SQLITE_NULLEQ)?2:3);
    if( res2 ){
      goto jump_to_p2;
    }
  }
  break;
}

    op_column_read_header:
      i = pC->nHdrParsed;
      offset64 = aOffset[i];
      zHdr = zData + pC->iHdrOffset;
      zEndHdr = zData + aOffset[0];
      testcase( zHdr>=zEndHdr );
      do{
        if( (pC->aType[i] = t = zHdr[0])<0x80 ){
          zHdr++;
          offset64 += sqlite3VdbeOneByteSerialTypeLen(t);
        }else{
          zHdr += sqlite3GetVarint32(zHdr, &t);
          pC->aType[i] = t;
          offset64 += sqlite3VdbeSerialTypeLen(t);
        }

        aOffset[++i] = (u32)(offset64 & 0xffffffff);
      }while( i<=p2 && zHdr<zEndHdr );

      /* The record is corrupt if any of the following are true:
      ** (1) the bytes of the header extend past the declared header size
      ** (2) the entire header was used but not all data was used
      ** (3) the end of the data extends beyond the end of the record.
      */

  pCx = allocateCursor(p, pOp->p1, pOrig->nField, -1, CURTYPE_BTREE);
  if( pCx==0 ) goto no_mem;
  pCx->nullRow = 1;
  pCx->isEphemeral = 1;
  pCx->pKeyInfo = pOrig->pKeyInfo;
  pCx->isTable = pOrig->isTable;
  pCx->pgnoRoot = pOrig->pgnoRoot;
  pCx->isOrdered = pOrig->isOrdered;
  rc = sqlite3BtreeCursor(pOrig->pBtx, pCx->pgnoRoot, BTREE_WRCSR,
                          pCx->pKeyInfo, pCx->uc.pCursor);
  /* The sqlite3BtreeCursor() routine can only fail for the first cursor
  ** opened for a database.  Since there is already an open cursor when this
  ** opcode is run, the sqlite3BtreeCursor() cannot fail */
  assert( rc==SQLITE_OK );
  break;

#ifdef SQLITE_TEST
  sqlite3_sort_count++;
  sqlite3_search_count--;
#endif
  p->aCounter[SQLITE_STMTSTATUS_SORT]++;
  /* Fall through into OP_Rewind */
}
/* Opcode: Rewind P1 P2 * * *
**
** The next use of the Rowid or Column or Next instruction for P1 
** will refer to the first entry in the database table or index.
** If the table or index is empty, jump immediately to P2.
** If the table or index is not empty, fall through to the following 
** instruction.
**




** This opcode leaves the cursor configured to move in forward order,
** from the beginning toward the end.  In other words, the cursor is
** configured to use Next, not Prev.
*/
case OP_Rewind: {        /* jump */
  VdbeCursor *pC;
  BtCursor *pCrsr;
  int res;

  assert( pOp->p1>=0 && pOp->p1<p->nCursor );
  assert( pOp->p5==0 );
  pC = p->apCsr[pOp->p1];
  assert( pC!=0 );
  assert( isSorter(pC)==(pOp->opcode==OP_SorterSort) );
  res = 1;
#ifdef SQLITE_DEBUG
  pC->seekOp = OP_Rewind;
#endif
  if( isSorter(pC) ){
    rc = sqlite3VdbeSorterRewind(pC, &res);
  }else{
    assert( pC->eCurType==CURTYPE_BTREE );
    pCrsr = pC->uc.pCursor;
    assert( pCrsr );
    rc = sqlite3BtreeFirst(pCrsr, &res);



    pC->deferredMoveto = 0;
    pC->cacheStatus = CACHE_STALE;
  }
  if( rc ) goto abort_due_to_error;
  pC->nullRow = (u8)res;
  assert( pOp->p2>0 && pOp->p2<p->nOp );
  VdbeBranchTaken(res!=0,2);

    for(i=0; i<p->nMem; i++){
      aMem[i].pScopyFrom = 0;  /* Prevent false-positive AboutToChange() errs */
      aMem[i].flags |= MEM_Undefined; /* Cause a fault if this reg is reused */
    }
  }
#endif
  pOp = &aOp[-1];
  goto check_for_interrupt;

}

/* Opcode: Param P1 P2 * * *
**
** This opcode is only ever present in sub-programs called via the 
** OP_Program instruction. Copy a value currently stored in a memory 
** cell of the calling (parent) frame to cell P2 in the current frames 

  Mem *pMem;
  assert( pOp->p1>0 && pOp->p1<=(p->nMem+1 - p->nCursor) );
  assert( pOp->p3==0 || pOp->opcode==OP_AggValue );
  pMem = &aMem[pOp->p1];
  assert( (pMem->flags & ~(MEM_Null|MEM_Agg))==0 );
#ifndef SQLITE_OMIT_WINDOWFUNC
  if( pOp->p3 ){
    memAboutToChange(p, &aMem[pOp->p3]);
    rc = sqlite3VdbeMemAggValue(pMem, &aMem[pOp->p3], pOp->p4.pFunc);
    pMem = &aMem[pOp->p3];
  }else
#endif
  {
    rc = sqlite3VdbeMemFinalize(pMem, pOp->p4.pFunc);
  }

    sqlite3ResetOneSchema(db, resetSchemaOnFault-1);
  }

  /* This is the only way out of this procedure.  We have to
  ** release the mutexes on btrees that were acquired at the
  ** top. */
vdbe_return:
#ifndef SQLITE_OMIT_PROGRESS_CALLBACK
  while( nVmStep>=nProgressLimit && db->xProgress!=0 ){
    nProgressLimit += db->nProgressOps;
    if( db->xProgress(db->pProgressArg) ){
      nProgressLimit = 0xffffffff;
      rc = SQLITE_INTERRUPT;
      goto abort_due_to_error;
    }
  }
#endif
  p->aCounter[SQLITE_STMTSTATUS_VM_STEP] += (int)nVmStep;
  sqlite3VdbeLeave(p);
  assert( rc!=SQLITE_OK || nExtraDelete==0 
       || sqlite3_strlike("DELETE%",p->zSql,0)!=0 
  );
  return rc;

    ** In this case, allocate space at p->aAlloc[] to copy the requested
    ** range into. Then return a copy of pointer p->aAlloc to the caller.  */
    int nRem;                     /* Bytes remaining to copy */

    /* Extend the p->aAlloc[] allocation if required. */
    if( p->nAlloc<nByte ){
      u8 *aNew;
      sqlite3_int64 nNew = MAX(128, 2*(sqlite3_int64)p->nAlloc);
      while( nByte>nNew ) nNew = nNew*2;
      aNew = sqlite3Realloc(p->aAlloc, nNew);
      if( !aNew ) return SQLITE_NOMEM_BKPT;
      p->nAlloc = nNew;
      p->aAlloc = aNew;
    }

  }

  if( pSorter->list.aMemory ){
    int nMin = pSorter->iMemory + nReq;

    if( nMin>pSorter->nMemory ){
      u8 *aNew;
      sqlite3_int64 nNew = 2 * (sqlite3_int64)pSorter->nMemory;
      int iListOff = -1;
      if( pSorter->list.pList ){
        iListOff = (u8*)pSorter->list.pList - pSorter->list.aMemory;

      }
      while( nNew < nMin ) nNew = nNew*2;
      if( nNew > pSorter->mxPmaSize ) nNew = pSorter->mxPmaSize;
      if( nNew < nMin ) nNew = nMin;

      aNew = sqlite3Realloc(pSorter->list.aMemory, nNew);
      if( !aNew ) return SQLITE_NOMEM_BKPT;
      if( iListOff>=0 ){
        pSorter->list.pList = (SorterRecord*)&aNew[iListOff];
      }
      pSorter->list.aMemory = aNew;
      pSorter->nMemory = nNew;
    }

    pNew = (SorterRecord*)&pSorter->list.aMemory[pSorter->iMemory];
    pSorter->iMemory += ROUND8(nReq);
    if( pSorter->list.pList ){

          assert( pExpr->pLeft==0 && pExpr->pRight==0 );
          assert( pExpr->x.pList==0 );
          assert( pExpr->x.pSelect==0 );
          pOrig = pEList->a[j].pExpr;
          if( (pNC->ncFlags&NC_AllowAgg)==0 && ExprHasProperty(pOrig, EP_Agg) ){
            sqlite3ErrorMsg(pParse, "misuse of aliased aggregate %s", zAs);
            return WRC_Abort;
          }
          if( (pNC->ncFlags&NC_AllowWin)==0 && ExprHasProperty(pOrig, EP_Win) ){
            sqlite3ErrorMsg(pParse, "misuse of aliased window function %s",zAs);
            return WRC_Abort;
          }
          if( sqlite3ExprVectorSize(pOrig)!=1 ){
            sqlite3ErrorMsg(pParse, "row value misused");
            return WRC_Abort;
          }
          resolveAlias(pParse, pEList, j, pExpr, "", nSubquery);
          cnt = 1;

      int no_such_func = 0;       /* True if no such function exists */
      int wrong_num_args = 0;     /* True if wrong number of arguments */
      int is_agg = 0;             /* True if is an aggregate function */
      int nId;                    /* Number of characters in function name */
      const char *zId;            /* The function name. */
      FuncDef *pDef;              /* Information about the function */
      u8 enc = ENC(pParse->db);   /* The database encoding */
      int savedAllowFlags = (pNC->ncFlags & (NC_AllowAgg | NC_AllowWin));

      assert( !ExprHasProperty(pExpr, EP_xIsSelect) );
      zId = pExpr->u.zToken;
      nId = sqlite3Strlen30(zId);
      pDef = sqlite3FindFunction(pParse->db, zId, n, enc, 0);
      if( pDef==0 ){
        pDef = sqlite3FindFunction(pParse->db, zId, -2, enc, 0);

          pNC->nErr++;
        }else if( wrong_num_args ){
          sqlite3ErrorMsg(pParse,"wrong number of arguments to function %.*s()",
               nId, zId);
          pNC->nErr++;
        }
        if( is_agg ){
          /* Window functions may not be arguments of aggregate functions.
          ** Or arguments of other window functions. But aggregate functions
          ** may be arguments for window functions.  */
#ifndef SQLITE_OMIT_WINDOWFUNC
          pNC->ncFlags &= ~(NC_AllowWin | (!pExpr->y.pWin ? NC_AllowAgg : 0));
#else
          pNC->ncFlags &= ~NC_AllowAgg;
#endif
        }
      }
      sqlite3WalkExprList(pWalker, pList);
      if( is_agg ){
#ifndef SQLITE_OMIT_WINDOWFUNC
        if( pExpr->y.pWin ){
          Select *pSel = pNC->pWinSelect;
          sqlite3WindowUpdate(pParse, pSel->pWinDefn, pExpr->y.pWin, pDef);
          sqlite3WalkExprList(pWalker, pExpr->y.pWin->pPartition);
          sqlite3WalkExprList(pWalker, pExpr->y.pWin->pOrderBy);
          sqlite3WalkExpr(pWalker, pExpr->y.pWin->pFilter);
          if( 0==pSel->pWin 
           || 0==sqlite3WindowCompare(pParse, pSel->pWin, pExpr->y.pWin) 
          ){
            pExpr->y.pWin->pNextWin = pSel->pWin;
            pSel->pWin = pExpr->y.pWin;
          }
          pNC->ncFlags |= NC_HasWin;
        }else
#endif /* SQLITE_OMIT_WINDOWFUNC */
        {
          NameContext *pNC2 = pNC;
          pExpr->op = TK_AGG_FUNCTION;
          pExpr->op2 = 0;
          while( pNC2 && !sqlite3FunctionUsesThisSrc(pExpr, pNC2->pSrcList) ){
            pExpr->op2++;
            pNC2 = pNC2->pNext;
          }
          assert( pDef!=0 );
          if( pNC2 ){
            assert( SQLITE_FUNC_MINMAX==NC_MinMaxAgg );
            testcase( (pDef->funcFlags & SQLITE_FUNC_MINMAX)!=0 );
            pNC2->ncFlags |= NC_HasAgg | (pDef->funcFlags & SQLITE_FUNC_MINMAX);

          }

        }
        pNC->ncFlags |= savedAllowFlags;
      }
      /* FIX ME:  Compute pExpr->affinity based on the expected return
      ** type of the function 
      */
      return WRC_Prune;
    }
#ifndef SQLITE_OMIT_SUBQUERY

      p->pOrderBy = 0;
    }
  
    /* Recursively resolve names in all subqueries
    */
    for(i=0; i<p->pSrc->nSrc; i++){
      struct SrcList_item *pItem = &p->pSrc->a[i];
      if( pItem->pSelect && (pItem->pSelect->selFlags & SF_Resolved)==0 ){
        NameContext *pNC;         /* Used to iterate name contexts */
        int nRef = 0;             /* Refcount for pOuterNC and outer contexts */
        const char *zSavedContext = pParse->zAuthContext;

        /* Count the total number of references to pOuterNC and all of its
        ** parent contexts. After resolving references to expressions in
        ** pItem->pSelect, check if this value has changed. If so, then

          sqlite3ErrorMsg(pParse, "aggregate functions are not allowed in "
              "the GROUP BY clause");
          return WRC_Abort;
        }
      }
    }

#ifndef SQLITE_OMIT_WINDOWFUNC
    if( IN_RENAME_OBJECT ){
      Window *pWin;
      for(pWin=p->pWinDefn; pWin; pWin=pWin->pNextWin){
        if( sqlite3ResolveExprListNames(&sNC, pWin->pOrderBy)
         || sqlite3ResolveExprListNames(&sNC, pWin->pPartition)
        ){
          return WRC_Abort;
        }
      }
    }
#endif

    /* If this is part of a compound SELECT, check that it has the right
    ** number of expressions in the select list. */
    if( p->pNext && p->pEList->nExpr!=p->pNext->pEList->nExpr ){
      sqlite3SelectWrongNumTermsError(pParse, p->pNext);
      return WRC_Abort;
    }

  NameContext *pNC,       /* Namespace to resolve expressions in. */
  Expr *pExpr             /* The expression to be analyzed. */
){
  u16 savedHasAgg;
  Walker w;

  if( pExpr==0 ) return SQLITE_OK;
  savedHasAgg = pNC->ncFlags & (NC_HasAgg|NC_MinMaxAgg|NC_HasWin);
  pNC->ncFlags &= ~(NC_HasAgg|NC_MinMaxAgg|NC_HasWin);
  w.pParse = pNC->pParse;
  w.xExprCallback = resolveExprStep;
  w.xSelectCallback = resolveSelectStep;
  w.xSelectCallback2 = 0;
  w.u.pNC = pNC;
#if SQLITE_MAX_EXPR_DEPTH>0
  w.pParse->nHeight += pExpr->nHeight;
  if( sqlite3ExprCheckHeight(w.pParse, w.pParse->nHeight) ){
    return SQLITE_ERROR;
  }
#endif
  sqlite3WalkExpr(&w, pExpr);
#if SQLITE_MAX_EXPR_DEPTH>0
  w.pParse->nHeight -= pExpr->nHeight;
#endif
  assert( EP_Agg==NC_HasAgg );
  assert( EP_Win==NC_HasWin );
  testcase( pNC->ncFlags & NC_HasAgg );
  testcase( pNC->ncFlags & NC_HasWin );
  ExprSetProperty(pExpr, pNC->ncFlags & (NC_HasAgg|NC_HasWin) );

  pNC->ncFlags |= savedHasAgg;
  return pNC->nErr>0 || w.pParse->nErr>0;
}

/*
** Resolve all names for all expression in an expression list.  This is
** just like sqlite3ResolveExprNames() except that it works for an expression

  if( op==TK_AND && pParse->nErr==0 && !IN_RENAME_OBJECT ){
    /* Take advantage of short-circuit false optimization for AND */
    p = sqlite3ExprAnd(pParse->db, pLeft, pRight);
  }else{
    p = sqlite3DbMallocRawNN(pParse->db, sizeof(Expr));
    if( p ){
      memset(p, 0, sizeof(Expr));
      p->op = op & 0xff;
      p->iAgg = -1;
    }
    sqlite3ExprAttachSubtrees(pParse->db, p, pLeft, pRight);
  }
  if( p ) {
    sqlite3ExprCheckHeight(pParse, p->nHeight);
  }

** argument. If an OOM condition is encountered, NULL is returned
** and the db->mallocFailed flag set.
*/
#ifndef SQLITE_OMIT_CTE
static With *withDup(sqlite3 *db, With *p){
  With *pRet = 0;
  if( p ){
    sqlite3_int64 nByte = sizeof(*p) + sizeof(p->a[0]) * (p->nCte-1);
    pRet = sqlite3DbMallocZero(db, nByte);
    if( pRet ){
      int i;
      pRet->nCte = p->nCte;
      for(i=0; i<p->nCte; i++){
        pRet->a[i].pSelect = sqlite3SelectDup(db, p->a[i].pSelect, 0);
        pRet->a[i].pCols = sqlite3ExprListDup(db, p->a[i].pCols, 0);

    if( pList==0 ){
      goto no_mem;
    }
    pList->nExpr = 0;
  }else if( (pList->nExpr & (pList->nExpr-1))==0 ){
    ExprList *pNew;
    pNew = sqlite3DbRealloc(db, pList, 
         sizeof(*pList)+(2*(sqlite3_int64)pList->nExpr-1)*sizeof(pList->a[0]));
    if( pNew==0 ){
      goto no_mem;
    }
    pList = pNew;
  }
  pItem = &pList->a[pList->nExpr++];
  assert( offsetof(struct ExprList_item,zName)==sizeof(pItem->pExpr) );

** an ordinary JOIN.  The p argument is the WHERE clause.  If the WHERE
** clause requires that some column of the right table of the LEFT JOIN
** be non-NULL, then the LEFT JOIN can be safely converted into an
** ordinary join.
*/
SQLITE_PRIVATE int sqlite3ExprImpliesNonNullRow(Expr *p, int iTab){
  Walker w;
  p = sqlite3ExprSkipCollate(p);
  while( p ){
    if( p->op==TK_NOTNULL ){
      p = p->pLeft;
    }else if( p->op==TK_AND ){
      if( sqlite3ExprImpliesNonNullRow(p->pLeft, iTab) ) return 1;
      p = p->pRight;
    }else{
      break;
    }
  }
  w.xExprCallback = impliesNotNullRow;
  w.xSelectCallback = 0;
  w.xSelectCallback2 = 0;
  w.eCode = 0;
  w.u.iCur = iTab;
  sqlite3WalkExpr(&w, p);
  return w.eCode;

    pVTab = sqlite3GetVTable(db, pTab);
    if( pVTab->pVtab->pModule->xRename==0 ){
      pVTab = 0;
    }
  }
#endif

  /* Begin a transaction for database iDb. Then modify the schema cookie
  ** (since the ALTER TABLE modifies the schema). Call sqlite3MayAbort(),
  ** as the scalar functions (e.g. sqlite_rename_table()) invoked by the 
  ** nested SQL may raise an exception.  */

  v = sqlite3GetVdbe(pParse);
  if( v==0 ){
    goto exit_rename_table;
  }
  sqlite3MayAbort(pParse);

  /* figure out how many UTF-8 characters are in zName */
  zTabName = pTab->zName;
  nTabName = sqlite3Utf8CharLen(zTabName, -1);

  /* Rewrite all CREATE TABLE, INDEX, TRIGGER or VIEW statements in
  ** the schema to use the new table name.  */

  ** SQLite tables) that are identified by the name of the virtual table.
  */
#ifndef SQLITE_OMIT_VIRTUALTABLE
  if( pVTab ){
    int i = ++pParse->nMem;
    sqlite3VdbeLoadString(v, i, zName);
    sqlite3VdbeAddOp4(v, OP_VRename, i, 0, 0,(const char*)pVTab, P4_VTAB);

  }
#endif

  renameReloadSchema(pParse, iDb);
  renameTestSchema(pParse, zDb, iDb==1);

exit_rename_table:

    goto exit_rename_column;
  }

  /* Do the rename operation using a recursive UPDATE statement that
  ** uses the sqlite_rename_column() SQL function to compute the new
  ** CREATE statement text for the sqlite_master table.
  */
  sqlite3MayAbort(pParse);
  zNew = sqlite3NameFromToken(db, pNew);
  if( !zNew ) goto exit_rename_column;
  assert( pNew->n>0 );
  bQuote = sqlite3Isquote(pNew->z[0]);
  sqlite3NestedParse(pParse, 
      "UPDATE \"%w\".%s SET "
      "sql = sqlite_rename_column(sql, type, name, %Q, %Q, %d, %Q, %d, %d) "

  ** remove the entry from the db->aDb[] array. i.e. put everything back the
  ** way we found it.
  */
  if( rc==SQLITE_OK ){
    sqlite3BtreeEnterAll(db);
    db->init.iDb = 0;
    db->mDbFlags &= ~(DBFLAG_SchemaKnownOk);
    if( !REOPEN_AS_MEMDB(db) ){
      rc = sqlite3Init(db, &zErrDyn);
    }
    sqlite3BtreeLeaveAll(db);
    assert( zErrDyn==0 || rc!=SQLITE_OK );
  }
#ifdef SQLITE_USER_AUTHENTICATION
  if( rc==SQLITE_OK && !REOPEN_AS_MEMDB(db) ){
    u8 newAuth = 0;
    rc = sqlite3UserAuthCheckLogin(db, zName, &newAuth);
    if( newAuth<db->auth.authLevel ){
      rc = SQLITE_AUTH_USER;
    }
  }
#endif

  if( pParse->nErr ) return;
  assert( pParse->nested<10 );  /* Nesting should only be of limited depth */
  va_start(ap, zFormat);
  zSql = sqlite3VMPrintf(db, zFormat, ap);
  va_end(ap);
  if( zSql==0 ){
    /* This can result either from an OOM or because the formatted string
    ** exceeds SQLITE_LIMIT_LENGTH.  In the latter case, we need to set
    ** an error */
    if( !db->mallocFailed ) pParse->rc = SQLITE_TOOBIG;
    pParse->nErr++;
    return;
  }
  pParse->nested++;
  memcpy(saveBuf, PARSE_TAIL(pParse), PARSE_TAIL_SZ);
  memset(PARSE_TAIL(pParse), 0, PARSE_TAIL_SZ);
  sqlite3RunParser(pParse, zSql, &zErrMsg);
  sqlite3DbFree(db, zErrMsg);
  sqlite3DbFree(db, zSql);

  }
  if( nTerm==1
   && pCol
   && sqlite3StrICmp(sqlite3ColumnType(pCol,""), "INTEGER")==0
   && sortOrder!=SQLITE_SO_DESC
  ){
    if( IN_RENAME_OBJECT && pList ){
      Expr *pCExpr = sqlite3ExprSkipCollate(pList->a[0].pExpr);
      sqlite3RenameTokenRemap(pParse, &pTab->iPKey, pCExpr);
    }
    pTab->iPKey = iCol;
    pTab->keyConf = (u8)onError;
    assert( autoInc==0 || autoInc==1 );
    pTab->tabFlags |= autoInc*TF_Autoincrement;
    if( pList ) pParse->iPkSortOrder = pList->a[0].sortOrder;
  }else if( autoInc ){

    sqlite3CreateIndex(pParse, 0, 0, 0, pList, pTab->keyConf, 0, 0, 0, 0,
                       SQLITE_IDXTYPE_PRIMARYKEY);
    if( db->mallocFailed || pParse->nErr ) return;
    pPk = sqlite3PrimaryKeyIndex(pTab);
    pTab->iPKey = -1;
  }else{
    pPk = sqlite3PrimaryKeyIndex(pTab);
    assert( pPk!=0 );

    /*
    ** Remove all redundant columns from the PRIMARY KEY.  For example, change
    ** "PRIMARY KEY(a,b,a,b,c,b,c,d)" into just "PRIMARY KEY(a,b,c,d)".  Later
    ** code assumes the PRIMARY KEY contains no repeated columns.
    */
    for(i=j=1; i<pPk->nKeyCol; i++){

      sqlite3ErrorMsg(pParse, "");
      return;
    }
    p->tnum = db->init.newTnum;
    if( p->tnum==1 ) p->tabFlags |= TF_Readonly;
  }

  assert( (p->tabFlags & TF_HasPrimaryKey)==0
       || p->iPKey>=0 || sqlite3PrimaryKeyIndex(p)!=0 );
  assert( (p->tabFlags & TF_HasPrimaryKey)!=0
       || (p->iPKey<0 && sqlite3PrimaryKeyIndex(p)==0) );

  /* Special processing for WITHOUT ROWID Tables */
  if( tabOpts & TF_WithoutRowid ){
    if( (p->tabFlags & TF_Autoincrement) ){
      sqlite3ErrorMsg(pParse,
          "AUTOINCREMENT not allowed on WITHOUT ROWID tables");
      return;
    }

  }
  pDb = &db->aDb[iDb];

  assert( pTab!=0 );
  assert( pParse->nErr==0 );
  if( sqlite3StrNICmp(pTab->zName, "sqlite_", 7)==0 
       && db->init.busy==0
       && pTblName!=0
#if SQLITE_USER_AUTHENTICATION
       && sqlite3UserAuthTable(pTab->zName)==0
#endif
#ifdef SQLITE_ALLOW_SQLITE_MASTER_INDEX
       && sqlite3StrICmp(&pTab->zName[7],"master")!=0
#endif

 ){
    sqlite3ErrorMsg(pParse, "table %s may not be indexed", pTab->zName);
    goto exit_create_index;
  }
#ifndef SQLITE_OMIT_VIEW
  if( pTab->pSelect ){
    sqlite3ErrorMsg(pParse, "views may not be indexed");

    pList = sqlite3ExprListAppend(pParse, 0,
              sqlite3ExprAlloc(db, TK_ID, &prevCol, 0));
    if( pList==0 ) goto exit_create_index;
    assert( pList->nExpr==1 );
    sqlite3ExprListSetSortOrder(pList, sortOrder);
  }else{
    sqlite3ExprListCheckLength(pParse, pList, "index");
    if( pParse->nErr ) goto exit_create_index;
  }

  /* Figure out how many bytes of space are required to store explicitly
  ** specified collation sequence names.
  */
  for(i=0; i<pList->nExpr; i++){
    Expr *pExpr = pList->a[i].pExpr;
    assert( pExpr!=0 );
    if( pExpr->op==TK_COLLATE ){
      nExtra += (1 + sqlite3Strlen30(pExpr->u.zToken));
    }
  }

  /* 
  ** Allocate the index structure. 
  */
  nName = sqlite3Strlen30(zName);
  nExtraCol = pPk ? pPk->nKeyCol : 1;
  assert( pList->nExpr + nExtraCol <= 32767 /* Fits in i16 */ );
  pIndex = sqlite3AllocateIndexObject(db, pList->nExpr + nExtraCol,
                                      nName + nExtra + 1, &zExtra);
  if( db->mallocFailed ){
    goto exit_create_index;
  }
  assert( EIGHT_BYTE_ALIGNMENT(pIndex->aiRowLogEst) );
  assert( EIGHT_BYTE_ALIGNMENT(pIndex->azColl) );

  sqlite3 *db,      /* Connection to notify of malloc failures */
  void *pArray,     /* Array of objects.  Might be reallocated */
  int szEntry,      /* Size of each object in the array */
  int *pnEntry,     /* Number of objects currently in use */
  int *pIdx         /* Write the index of a new slot here */
){
  char *z;
  sqlite3_int64 n = *pIdx = *pnEntry;
  if( (n & (n-1))==0 ){
    sqlite3_int64 sz = (n==0) ? 1 : 2*n;
    void *pNew = sqlite3DbRealloc(db, pArray, sz*szEntry);
    if( pNew==0 ){
      *pIdx = -1;
      return pArray;
    }
    pArray = pNew;
  }
  z = (char*)pArray;
  memset(&z[n * szEntry], 0, szEntry);

  ++*pnEntry;
  return pArray;
}

/*
** Append a new element to the given IdList.  Create a new IdList if
** need be.

  assert( nExtra>=1 );
  assert( pSrc!=0 );
  assert( iStart<=pSrc->nSrc );

  /* Allocate additional space if needed */
  if( (u32)pSrc->nSrc+nExtra>pSrc->nAlloc ){
    SrcList *pNew;
    sqlite3_int64 nAlloc = 2*(sqlite3_int64)pSrc->nSrc+nExtra;
    sqlite3 *db = pParse->db;

    if( pSrc->nSrc+nExtra>=SQLITE_MAX_SRCLIST ){
      sqlite3ErrorMsg(pParse, "too many FROM clause terms, max: %d",
                      SQLITE_MAX_SRCLIST);
      return 0;
    }

  Index *pIdx       /* The index that triggers the constraint */
){
  char *zErr;
  int j;
  StrAccum errMsg;
  Table *pTab = pIdx->pTable;

  sqlite3StrAccumInit(&errMsg, pParse->db, 0, 0, 
                      pParse->db->aLimit[SQLITE_LIMIT_LENGTH]);
  if( pIdx->aColExpr ){
    sqlite3_str_appendf(&errMsg, "index '%q'", pIdx->zName);
  }else{
    for(j=0; j<pIdx->nKeyCol; j++){
      char *zCol;
      assert( pIdx->aiColumn[j]>=0 );
      zCol = pTab->aCol[pIdx->aiColumn[j]].zName;

      if( sqlite3StrICmp(zName, pWith->a[i].zName)==0 ){
        sqlite3ErrorMsg(pParse, "duplicate WITH table name: %s", zName);
      }
    }
  }

  if( pWith ){
    sqlite3_int64 nByte = sizeof(*pWith) + (sizeof(pWith->a[1]) * pWith->nCte);
    pNew = sqlite3DbRealloc(db, pWith, nByte);
  }else{
    pNew = sqlite3DbMallocZero(db, sizeof(*pWith));
  }
  assert( (pNew!=0 && zName!=0) || db->mallocFailed );

  if( db->mallocFailed ){

** Set the LIKEOPT flag on the 2-argument function with the given name.
*/
static void setLikeOptFlag(sqlite3 *db, const char *zName, u8 flagVal){
  FuncDef *pDef;
  pDef = sqlite3FindFunction(db, zName, 2, SQLITE_UTF8, 0);
  if( ALWAYS(pDef) ){
    pDef->funcFlags |= flagVal;
  }
  pDef = sqlite3FindFunction(db, zName, 3, SQLITE_UTF8, 0);
  if( pDef ){
    pDef->funcFlags |= flagVal;
  }
}

/*
** Register the built-in LIKE and GLOB functions.  The caseSensitive
** parameter determines whether or not the LIKE operator is case
** sensitive.  GLOB is always case sensitive.

        sqlite3VdbeAddOp2(v, iField<0 ? OP_IntCopy : OP_SCopy, x, regIdx+i);
        VdbeComment((v, "%s", iField<0 ? "rowid" : pTab->aCol[iField].zName));
      }
    }
    sqlite3VdbeAddOp3(v, OP_MakeRecord, regIdx, pIdx->nColumn, aRegIdx[ix]);
    VdbeComment((v, "for %s", pIdx->zName));
#ifdef SQLITE_ENABLE_NULL_TRIM
    if( pIdx->idxType==SQLITE_IDXTYPE_PRIMARYKEY ){
      sqlite3SetMakeRecordP5(v, pIdx->pTable);
    }
#endif

    /* In an UPDATE operation, if this index is the PRIMARY KEY index 
    ** of a WITHOUT ROWID table and there has been no change the
    ** primary key, then no collision is possible.  The collision detection
    ** logic below can all be skipped. */
    if( isUpdate && pPk==pIdx && pkChng==0 ){

    }
    for(pSrcIdx=pSrc->pIndex; pSrcIdx; pSrcIdx=pSrcIdx->pNext){
      if( xferCompatibleIndex(pDestIdx, pSrcIdx) ) break;
    }
    if( pSrcIdx==0 ){
      return 0;    /* pDestIdx has no corresponding index in pSrc */
    }
    if( pSrcIdx->tnum==pDestIdx->tnum && pSrc->pSchema==pDest->pSchema
         && sqlite3FaultSim(411)==SQLITE_OK ){
      /* The sqlite3FaultSim() call allows this corruption test to be
      ** bypassed during testing, in order to exercise other corruption tests
      ** further downstream. */
      return 0;   /* Corrupt schema - two indexes on the same btree */
    }
  }
#ifndef SQLITE_OMIT_CHECK
  if( pDest->pCheck && sqlite3ExprListCompare(pSrc->pCheck,pDest->pCheck,-1) ){
    return 0;   /* Tables have different CHECK constraints.  Ticket #2252 */
  }
#endif
#ifndef SQLITE_OMIT_FOREIGN_KEY

      addr1 = sqlite3VdbeAddOp2(v, OP_Rowid, iSrc, regRowid);
      sqlite3VdbeVerifyAbortable(v, onError);
      addr2 = sqlite3VdbeAddOp3(v, OP_NotExists, iDest, 0, regRowid);
      VdbeCoverage(v);
      sqlite3RowidConstraint(pParse, onError, pDest);
      sqlite3VdbeJumpHere(v, addr2);
      autoIncStep(pParse, regAutoinc, regRowid);
    }else if( pDest->pIndex==0 && !(db->mDbFlags & DBFLAG_VacuumInto) ){
      addr1 = sqlite3VdbeAddOp2(v, OP_NewRowid, iDest, regRowid);
    }else{
      addr1 = sqlite3VdbeAddOp2(v, OP_Rowid, iSrc, regRowid);
      assert( (pDest->tabFlags & TF_Autoincrement)==0 );
    }
    sqlite3VdbeAddOp3(v, OP_RowData, iSrc, regData, 1);
    if( db->mDbFlags & DBFLAG_Vacuum ){

        if( sqlite3_stricmp(sqlite3StrBINARY, zColl) ) break;
      }
      if( i==pSrcIdx->nColumn ){
        idxInsFlags = OPFLAG_USESEEKRESULT;
        sqlite3VdbeAddOp1(v, OP_SeekEnd, iDest);
      }
    }
    if( !HasRowid(pSrc) && pDestIdx->idxType==SQLITE_IDXTYPE_PRIMARYKEY ){
      idxInsFlags |= OPFLAG_NCHANGE;
    }
    sqlite3VdbeAddOp2(v, OP_IdxInsert, iDest, regData);
    sqlite3VdbeChangeP5(v, idxInsFlags|OPFLAG_APPEND);
    sqlite3VdbeAddOp2(v, OP_Next, iSrc, addr1+1); VdbeCoverage(v);
    sqlite3VdbeJumpHere(v, addr1);
    sqlite3VdbeAddOp2(v, OP_Close, iSrc, 0);

                            void (*xStep)(sqlite3_context*,int,sqlite3_value**),
                            void (*xFinal)(sqlite3_context*),
                            void (*xValue)(sqlite3_context*),
                            void (*xInv)(sqlite3_context*,int,sqlite3_value**),
                            void(*xDestroy)(void*));
  /* Version 3.26.0 and later */
  const char *(*normalized_sql)(sqlite3_stmt*);
  /* Version 3.28.0 and later */
  int (*stmt_isexplain)(sqlite3_stmt*);
  int (*value_frombind)(sqlite3_value*);
};

/*
** This is the function signature used for all extension entry points.  It
** is also defined in the file "loadext.c".
*/
typedef int (*sqlite3_loadext_entry)(

#define sqlite3_str_errcode            sqlite3_api->str_errcode
#define sqlite3_str_length             sqlite3_api->str_length
#define sqlite3_str_value              sqlite3_api->str_value
/* Version 3.25.0 and later */
#define sqlite3_create_window_function sqlite3_api->create_window_function
/* Version 3.26.0 and later */
#define sqlite3_normalized_sql         sqlite3_api->normalized_sql
/* Version 3.28.0 and later */
#define sqlite3_stmt_isexplain         sqlite3_api->isexplain
#define sqlite3_value_frombind         sqlite3_api->frombind
#endif /* !defined(SQLITE_CORE) && !defined(SQLITE_OMIT_LOAD_EXTENSION) */

#if !defined(SQLITE_CORE) && !defined(SQLITE_OMIT_LOAD_EXTENSION)
  /* This case when the file really is being compiled as a loadable 
  ** extension */
# define SQLITE_EXTENSION_INIT1     const sqlite3_api_routines *sqlite3_api=0;
# define SQLITE_EXTENSION_INIT2(v)  sqlite3_api=v;

  sqlite3_str_errcode,
  sqlite3_str_length,
  sqlite3_str_value,
  /* Version 3.25.0 and later */
  sqlite3_create_window_function,
  /* Version 3.26.0 and later */
#ifdef SQLITE_ENABLE_NORMALIZE
  sqlite3_normalized_sql,
#else
  0,
#endif
  /* Version 3.28.0 and later */
  sqlite3_stmt_isexplain,
  sqlite3_value_frombind
};

/*
** Attempt to load an SQLite extension library contained in the file
** zFile.  The entry point is zProc.  zProc may be 0 in which case a
** default entry point name (sqlite3_extension_init) is used.  Use
** of the default name is recommended.

/*
** Update the accumulator memory cells for an aggregate based on
** the current cursor position.
**
** If regAcc is non-zero and there are no min() or max() aggregates
** in pAggInfo, then only populate the pAggInfo->nAccumulator accumulator
** registers if register regAcc contains 0. The caller will take care
** of setting and clearing regAcc.
*/
static void updateAccumulator(Parse *pParse, int regAcc, AggInfo *pAggInfo){
  Vdbe *v = pParse->pVdbe;
  int i;
  int regHit = 0;
  int addrHitTest = 0;

  sqlite3ExprDelete(pParse->db, pInto);
  return;
}

/*
** This routine implements the OP_Vacuum opcode of the VDBE.
*/
SQLITE_PRIVATE SQLITE_NOINLINE int sqlite3RunVacuum(
  char **pzErrMsg,        /* Write error message here */
  sqlite3 *db,            /* Database connection */
  int iDb,                /* Which attached DB to vacuum */
  sqlite3_value *pOut     /* Write results here, if not NULL. VACUUM INTO */
){
  int rc = SQLITE_OK;     /* Return code from service routines */
  Btree *pMain;           /* The database being vacuumed */
  Btree *pTemp;           /* The temporary database we vacuum into */
  u32 saved_mDbFlags;     /* Saved value of db->mDbFlags */
  u64 saved_flags;        /* Saved value of db->flags */
  int saved_nChange;      /* Saved value of db->nChange */
  int saved_nTotalChange; /* Saved value of db->nTotalChange */
  u32 saved_openFlags;    /* Saved value of db->openFlags */
  u8 saved_mTrace;        /* Saved trace settings */
  Db *pDb = 0;            /* Database to detach at end of vacuum */
  int isMemDb;            /* True if vacuuming a :memory: database */
  int nRes;               /* Bytes of reserved space at the end of each page */
  int nDb;                /* Number of attached databases */
  const char *zDbMain;    /* Schema name of database to vacuum */
  const char *zOut;       /* Name of output file */

  if( !db->autoCommit ){
    sqlite3SetString(pzErrMsg, db, "cannot VACUUM from within a transaction");
    return SQLITE_ERROR; /* IMP: R-12218-18073 */
  }
  if( db->nVdbeActive>1 ){
    sqlite3SetString(pzErrMsg, db,"cannot VACUUM - SQL statements in progress");
    return SQLITE_ERROR; /* IMP: R-15610-35227 */
  }
  saved_openFlags = db->openFlags;
  if( pOut ){
    if( sqlite3_value_type(pOut)!=SQLITE_TEXT ){
      sqlite3SetString(pzErrMsg, db, "non-text filename");
      return SQLITE_ERROR;
    }
    zOut = (const char*)sqlite3_value_text(pOut);
    db->openFlags &= ~SQLITE_OPEN_READONLY;
    db->openFlags |= SQLITE_OPEN_CREATE|SQLITE_OPEN_READWRITE;
  }else{
    zOut = "";
  }

  /* Save the current value of the database flags so that it can be 
  ** restored before returning. Then set the writable-schema flag, and
  ** disable CHECK and foreign key constraints.  */

  ** actually occurs when doing a vacuum since the vacuum_db is initially
  ** empty.  Only the journal header is written.  Apparently it takes more
  ** time to parse and run the PRAGMA to turn journalling off than it does
  ** to write the journal header file.
  */
  nDb = db->nDb;
  rc = execSqlF(db, pzErrMsg, "ATTACH %Q AS vacuum_db", zOut);
  db->openFlags = saved_openFlags;
  if( rc!=SQLITE_OK ) goto end_of_vacuum;
  assert( (db->nDb-1)==nDb );
  pDb = &db->aDb[nDb];
  assert( strcmp(pDb->zDbSName,"vacuum_db")==0 );
  pTemp = pDb->pBt;
  if( pOut ){
    sqlite3_file *id = sqlite3PagerFile(sqlite3BtreePager(pTemp));
    i64 sz = 0;
    if( id->pMethods!=0 && (sqlite3OsFileSize(id, &sz)!=SQLITE_OK || sz>0) ){
      rc = SQLITE_ERROR;
      sqlite3SetString(pzErrMsg, db, "output file already exists");
      goto end_of_vacuum;
    }
    db->mDbFlags |= DBFLAG_VacuumInto;
  }
  nRes = sqlite3BtreeGetOptimalReserve(pMain);

  /* A VACUUM cannot change the pagesize of an encrypted database. */
#ifdef SQLITE_HAS_CODEC
  if( db->nextPagesize ){
    extern void sqlite3CodecGetKey(sqlite3*, int, void**, int*);

/*
** Add a new module argument to pTable->azModuleArg[].
** The string is not copied - the pointer is stored.  The
** string will be freed automatically when the table is
** deleted.
*/
static void addModuleArgument(Parse *pParse, Table *pTable, char *zArg){
  sqlite3_int64 nBytes = sizeof(char *)*(2+pTable->nModuleArg);
  char **azModuleArg;
  sqlite3 *db = pParse->db;
  if( pTable->nModuleArg+3>=db->aLimit[SQLITE_LIMIT_COLUMN] ){
    sqlite3ErrorMsg(pParse, "too many columns on %s", pTable->zName);
  }
  azModuleArg = sqlite3DbRealloc(db, pTable->azModuleArg, nBytes);
  if( azModuleArg==0 ){
    sqlite3DbFree(db, zArg);
  }else{
    int i = pTable->nModuleArg++;
    azModuleArg[i] = zArg;
    azModuleArg[i+1] = 0;

  pTable = pParse->pNewTable;
  if( pTable==0 ) return;
  assert( 0==pTable->pIndex );

  db = pParse->db;

  assert( pTable->nModuleArg==0 );
  addModuleArgument(pParse, pTable, sqlite3NameFromToken(db, pModuleName));
  addModuleArgument(pParse, pTable, 0);
  addModuleArgument(pParse, pTable, sqlite3DbStrDup(db, pTable->zName));
  assert( (pParse->sNameToken.z==pName2->z && pName2->z!=0)
       || (pParse->sNameToken.z==pName1->z && pName2->z==0)
  );
  pParse->sNameToken.n = (int)(
      &pModuleName->z[pModuleName->n] - pParse->sNameToken.z
  );

** virtual table currently under construction in pParse->pTable.
*/
static void addArgumentToVtab(Parse *pParse){
  if( pParse->sArg.z && pParse->pNewTable ){
    const char *z = (const char*)pParse->sArg.z;
    int n = pParse->sArg.n;
    sqlite3 *db = pParse->db;
    addModuleArgument(pParse, pParse->pNewTable, sqlite3DbStrNDup(db, z, n));
  }
}

/*
** The parser calls this routine after the CREATE VIRTUAL TABLE statement
** has been completely parsed.
*/

*/
static int growVTrans(sqlite3 *db){
  const int ARRAY_INCR = 5;

  /* Grow the sqlite3.aVTrans array if required */
  if( (db->nVTrans%ARRAY_INCR)==0 ){
    VTable **aVTrans;
    sqlite3_int64 nBytes = sizeof(sqlite3_vtab*)*
                                 ((sqlite3_int64)db->nVTrans + ARRAY_INCR);
    aVTrans = sqlite3DbRealloc(db, (void *)db->aVTrans, nBytes);
    if( !aVTrans ){
      return SQLITE_NOMEM_BKPT;
    }
    memset(&aVTrans[db->nVTrans], 0, sizeof(sqlite3_vtab *)*ARRAY_INCR);
    db->aVTrans = aVTrans;
  }

    return 0;
  }
  pMod->pEpoTab = pTab;
  pTab->nTabRef = 1;
  pTab->pSchema = db->aDb[0].pSchema;
  assert( pTab->nModuleArg==0 );
  pTab->iPKey = -1;
  addModuleArgument(pParse, pTab, sqlite3DbStrDup(db, pTab->zName));
  addModuleArgument(pParse, pTab, 0);
  addModuleArgument(pParse, pTab, sqlite3DbStrDup(db, pTab->zName));
  rc = vtabCallConstructor(db, pTab, pMod, pModule->xConnect, &zErr);
  if( rc ){
    sqlite3ErrorMsg(pParse, "%s", zErr);
    sqlite3DbFree(db, zErr);
    sqlite3VtabEponymousTableClear(db, pMod);
    return 0;
  }

    x.iIdxCol = iIdxCol;
    x.pIdxExpr = aColExpr->a[iIdxCol].pExpr;
    sqlite3WalkExpr(&w, pWInfo->pWhere);
    sqlite3WalkExprList(&w, pWInfo->pOrderBy);
    sqlite3WalkExprList(&w, pWInfo->pResultSet);
  }
}

/*
** The pTruth expression is always true because it is the WHERE clause
** a partial index that is driving a query loop.  Look through all of the
** WHERE clause terms on the query, and if any of those terms must be
** true because pTruth is true, then mark those WHERE clause terms as
** coded.
*/
static void whereApplyPartialIndexConstraints(
  Expr *pTruth,
  int iTabCur,
  WhereClause *pWC
){
  int i;
  WhereTerm *pTerm;
  while( pTruth->op==TK_AND ){
    whereApplyPartialIndexConstraints(pTruth->pLeft, iTabCur, pWC);
    pTruth = pTruth->pRight;
  }
  for(i=0, pTerm=pWC->a; i<pWC->nTerm; i++, pTerm++){
    Expr *pExpr;
    if( pTerm->wtFlags & TERM_CODED ) continue;
    pExpr = pTerm->pExpr;
    if( sqlite3ExprCompare(0, pExpr, pTruth, iTabCur)==0 ){
      pTerm->wtFlags |= TERM_CODED;
    }
  }
}

/*
** Generate code for the start of the iLevel-th loop in the WHERE clause
** implementation described by pWInfo.
*/
SQLITE_PRIVATE Bitmask sqlite3WhereCodeOneLoopStart(
  Parse *pParse,       /* Parsing context */

    ** OR clause, since the transformation will become invalid once we
    ** move forward to the next index.
    ** https://sqlite.org/src/info/4e8e4857d32d401f
    */
    if( pLevel->iLeftJoin==0 && (pWInfo->wctrlFlags & WHERE_OR_SUBCLAUSE)==0 ){
      whereIndexExprTrans(pIdx, iCur, iIdxCur, pWInfo);
    }

    /* If a partial index is driving the loop, try to eliminate WHERE clause
    ** terms from the query that must be true due to the WHERE clause of
    ** the partial index
    */
    if( pIdx->pPartIdxWhere ){
      whereApplyPartialIndexConstraints(pIdx->pPartIdxWhere, iCur, pWC);
    }

    /* Record the instruction used to terminate the loop. */
    if( pLoop->wsFlags & WHERE_ONEROW ){
      pLevel->op = OP_Noop;
    }else if( bRev ){
      pLevel->op = OP_Prev;
    }else{

        if( (pWC->a[iTerm].wtFlags & (TERM_VIRTUAL|TERM_CODED))!=0 ) continue;
        if( (pWC->a[iTerm].eOperator & WO_ALL)==0 ) continue;
        testcase( pWC->a[iTerm].wtFlags & TERM_ORINFO );
        pExpr = sqlite3ExprDup(db, pExpr, 0);
        pAndExpr = sqlite3ExprAnd(db, pAndExpr, pExpr);
      }
      if( pAndExpr ){
        /* The extra 0x10000 bit on the opcode is masked off and does not
        ** become part of the new Expr.op.  However, it does make the
        ** op==TK_AND comparison inside of sqlite3PExpr() false, and this
        ** prevents sqlite3PExpr() from implementing AND short-circuit 
        ** optimization, which we do not want here. */
        pAndExpr = sqlite3PExpr(pParse, TK_AND|0x10000, 0, pAndExpr);
      }
    }

    /* Run a separate WHERE clause for each term of the OR clause.  After
    ** eliminating duplicates from other WHERE clauses, the action for each
    ** sub-WHERE clause is to to invoke the main loop body as a subroutine.
    */

        ** that compares BLOBs. */
#ifdef SQLITE_LIKE_DOESNT_MATCH_BLOBS
        continue;
#else
        u32 x = pLevel->iLikeRepCntr;
        if( x>0 ){
          skipLikeAddr = sqlite3VdbeAddOp1(v, (x&1)?OP_IfNot:OP_If,(int)(x>>1));
          VdbeCoverageIf(v, (x&1)==1);
          VdbeCoverageIf(v, (x&1)==0);
        }

#endif
      }
#ifdef WHERETRACE_ENABLED /* 0xffff */
      if( sqlite3WhereTrace ){
        VdbeNoopComment((v, "WhereTerm[%d] (%p) priority=%d",
                         pWC->nTerm-j, pTerm, iLoop));
      }

    assert( p->x.pList==0 );
  }else if( ExprHasProperty(p, EP_xIsSelect) ){
    if( ExprHasProperty(p, EP_VarSelect) ) pMaskSet->bVarSelect = 1;
    mask |= exprSelectUsage(pMaskSet, p->x.pSelect);
  }else if( p->x.pList ){
    mask |= sqlite3WhereExprListUsage(pMaskSet, p->x.pList);
  }
#ifndef SQLITE_OMIT_WINDOWFUNC
  if( p->op==TK_FUNCTION && p->y.pWin ){
    mask |= sqlite3WhereExprListUsage(pMaskSet, p->y.pWin->pPartition);
    mask |= sqlite3WhereExprListUsage(pMaskSet, p->y.pWin->pOrderBy);
  }
#endif
  return mask;
}
SQLITE_PRIVATE Bitmask sqlite3WhereExprUsage(WhereMaskSet *pMaskSet, Expr *p){
  return p ? sqlite3WhereExprUsageNN(pMaskSet,p) : 0;
}
SQLITE_PRIVATE Bitmask sqlite3WhereExprListUsage(WhereMaskSet *pMaskSet, ExprList *pList){
  int i;

  /* First call xBestIndex() with all constraints usable. */
  WHERETRACE(0x800, ("BEGIN %s.addVirtual()\n", pSrc->pTab->zName));
  WHERETRACE(0x40, ("  VirtualOne: all usable\n"));
  rc = whereLoopAddVirtualOne(pBuilder, mPrereq, ALLBITS, 0, p, mNoOmit, &bIn);

  /* If the call to xBestIndex() with all terms enabled produced a plan
  ** that does not require any source tables (IOW: a plan with mBest==0)
  ** and does not use an IN(...) operator, then there is no point in making 
  ** any further calls to xBestIndex() since they will all return the same
  ** result (if the xBestIndex() implementation is sane). */
  if( rc==SQLITE_OK && ((mBest = (pNew->prereq & ~mPrereq))!=0 || bIn) ){
    int seenZero = 0;             /* True if a plan with no prereqs seen */
    int seenZeroNoIN = 0;         /* Plan with no prereqs and no IN(...) seen */
    Bitmask mPrev = 0;
    Bitmask mBestNoIn = 0;

    /* If the plan produced by the earlier call uses an IN(...) term, call
    ** xBestIndex again, this time with IN(...) terms disabled. */

      p->nValue++;
      p->nStep = 0;
    }
    sqlite3_result_int64(pCtx, p->nValue);
  }
}

/*
** Implementation of built-in window function nth_value(). This
** implementation is used in "slow mode" only - when the EXCLUDE clause
** is not set to the default value "NO OTHERS".
*/
struct NthValueCtx {
  i64 nStep;
  sqlite3_value *pValue;
};
static void nth_valueStepFunc(
  sqlite3_context *pCtx, 
  int nArg,
  sqlite3_value **apArg
){
  struct NthValueCtx *p;
  p = (struct NthValueCtx*)sqlite3_aggregate_context(pCtx, sizeof(*p));
  if( p ){
    i64 iVal;
    switch( sqlite3_value_numeric_type(apArg[1]) ){
      case SQLITE_INTEGER:
        iVal = sqlite3_value_int64(apArg[1]);
        break;
      case SQLITE_FLOAT: {
        double fVal = sqlite3_value_double(apArg[1]);
        if( ((i64)fVal)!=fVal ) goto error_out;
        iVal = (i64)fVal;
        break;
      }
      default:
        goto error_out;
    }
    if( iVal<=0 ) goto error_out;

    p->nStep++;
    if( iVal==p->nStep ){
      p->pValue = sqlite3_value_dup(apArg[0]);
      if( !p->pValue ){
        sqlite3_result_error_nomem(pCtx);
      }
    }
  }
  UNUSED_PARAMETER(nArg);
  UNUSED_PARAMETER(apArg);
  return;

 error_out:
  sqlite3_result_error(
      pCtx, "second argument to nth_value must be a positive integer", -1
  );
}
static void nth_valueFinalizeFunc(sqlite3_context *pCtx){
  struct NthValueCtx *p;
  p = (struct NthValueCtx*)sqlite3_aggregate_context(pCtx, 0);
  if( p && p->pValue ){
    sqlite3_result_value(pCtx, p->pValue);
    sqlite3_value_free(p->pValue);
    p->pValue = 0;
  }
}
#define nth_valueInvFunc noopStepFunc
#define nth_valueValueFunc noopValueFunc

static void first_valueStepFunc(
  sqlite3_context *pCtx, 
  int nArg,
  sqlite3_value **apArg
){
  struct NthValueCtx *p;
  p = (struct NthValueCtx*)sqlite3_aggregate_context(pCtx, sizeof(*p));
  if( p && p->pValue==0 ){
    p->pValue = sqlite3_value_dup(apArg[0]);
    if( !p->pValue ){
      sqlite3_result_error_nomem(pCtx);
    }
  }
  UNUSED_PARAMETER(nArg);
  UNUSED_PARAMETER(apArg);
}
static void first_valueFinalizeFunc(sqlite3_context *pCtx){
  struct NthValueCtx *p;
  p = (struct NthValueCtx*)sqlite3_aggregate_context(pCtx, sizeof(*p));
  if( p && p->pValue ){
    sqlite3_result_value(pCtx, p->pValue);
    sqlite3_value_free(p->pValue);
    p->pValue = 0;
  }
}
#define first_valueInvFunc noopStepFunc
#define first_valueValueFunc noopValueFunc

/*
** Implementation of built-in window function rank(). Assumes that
** the window frame has been set to:
**
**   RANGE BETWEEN UNBOUNDED PRECEDING AND CURRENT ROW 
*/
static void rankStepFunc(

  }
}

/*
** Implementation of built-in window function percent_rank(). Assumes that
** the window frame has been set to:
**
**   GROUPS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
*/
static void percent_rankStepFunc(
  sqlite3_context *pCtx, 
  int nArg,
  sqlite3_value **apArg
){
  struct CallCount *p;
  UNUSED_PARAMETER(nArg); assert( nArg==0 );
  UNUSED_PARAMETER(apArg);
  p = (struct CallCount*)sqlite3_aggregate_context(pCtx, sizeof(*p));
  if( p ){
    p->nTotal++;

  }



}

static void percent_rankInvFunc(
  sqlite3_context *pCtx, 
  int nArg,
  sqlite3_value **apArg
){
  struct CallCount *p;
  UNUSED_PARAMETER(nArg); assert( nArg==0 );
  UNUSED_PARAMETER(apArg);
  p = (struct CallCount*)sqlite3_aggregate_context(pCtx, sizeof(*p));
  p->nStep++;
}
static void percent_rankValueFunc(sqlite3_context *pCtx){
  struct CallCount *p;
  p = (struct CallCount*)sqlite3_aggregate_context(pCtx, sizeof(*p));
  if( p ){
    p->nValue = p->nStep;
    if( p->nTotal>1 ){
      double r = (double)p->nValue / (double)(p->nTotal-1);
      sqlite3_result_double(pCtx, r);
    }else{
      sqlite3_result_double(pCtx, 0.0);
    }

  }
}
#define percent_rankFinalizeFunc percent_rankValueFunc

/*
** Implementation of built-in window function cume_dist(). Assumes that
** the window frame has been set to:
**
**   GROUPS BETWEEN 1 FOLLOWING AND UNBOUNDED FOLLOWING
*/
static void cume_distStepFunc(
  sqlite3_context *pCtx, 
  int nArg,
  sqlite3_value **apArg
){
  struct CallCount *p;
  UNUSED_PARAMETER(nArg); assert( nArg==0 );
  UNUSED_PARAMETER(apArg);
  p = (struct CallCount*)sqlite3_aggregate_context(pCtx, sizeof(*p));
  if( p ){
    p->nTotal++;

  }

}
static void cume_distInvFunc(
  sqlite3_context *pCtx, 
  int nArg,
  sqlite3_value **apArg
){
  struct CallCount *p;
  UNUSED_PARAMETER(nArg); assert( nArg==0 );
  UNUSED_PARAMETER(apArg);
  p = (struct CallCount*)sqlite3_aggregate_context(pCtx, sizeof(*p));
  p->nStep++;
}
static void cume_distValueFunc(sqlite3_context *pCtx){
  struct CallCount *p;
  p = (struct CallCount*)sqlite3_aggregate_context(pCtx, 0);
  if( p ){
    double r = (double)(p->nStep) / (double)(p->nTotal);
    sqlite3_result_double(pCtx, r);
  }
}
#define cume_distFinalizeFunc cume_distValueFunc

/*
** Context object for ntile() window function.
*/
struct NtileCtx {
  i64 nTotal;                     /* Total rows in partition */
  i64 nParam;                     /* Parameter passed to ntile(N) */
  i64 iRow;                       /* Current row */
};

/*
** Implementation of ntile(). This assumes that the window frame has
** been coerced to:
**
**   ROWS CURRENT ROW AND UNBOUNDED FOLLOWING
*/
static void ntileStepFunc(
  sqlite3_context *pCtx, 
  int nArg,
  sqlite3_value **apArg
){
  struct NtileCtx *p;
  assert( nArg==1 ); UNUSED_PARAMETER(nArg);
  p = (struct NtileCtx*)sqlite3_aggregate_context(pCtx, sizeof(*p));
  if( p ){
    if( p->nTotal==0 ){
      p->nParam = sqlite3_value_int64(apArg[0]);

      if( p->nParam<=0 ){
        sqlite3_result_error(
            pCtx, "argument of ntile must be a positive integer", -1
        );
      }
    }
    p->nTotal++;
  }
}
static void ntileInvFunc(
  sqlite3_context *pCtx, 
  int nArg,
  sqlite3_value **apArg
){
  struct NtileCtx *p;
  assert( nArg==1 ); UNUSED_PARAMETER(nArg);
  UNUSED_PARAMETER(apArg);
  p = (struct NtileCtx*)sqlite3_aggregate_context(pCtx, sizeof(*p));
  p->iRow++;
}
static void ntileValueFunc(sqlite3_context *pCtx){
  struct NtileCtx *p;
  p = (struct NtileCtx*)sqlite3_aggregate_context(pCtx, sizeof(*p));
  if( p && p->nParam>0 ){
    int nSize = (p->nTotal / p->nParam);
    if( nSize==0 ){
      sqlite3_result_int64(pCtx, p->iRow+1);
    }else{
      i64 nLarge = p->nTotal - p->nParam*nSize;
      i64 iSmall = nLarge*(nSize+1);
      i64 iRow = p->iRow;

      assert( (nLarge*(nSize+1) + (p->nParam-nLarge)*nSize)==p->nTotal );

      if( iRow<iSmall ){
        sqlite3_result_int64(pCtx, 1 + iRow/(nSize+1));
      }else{
        sqlite3_result_int64(pCtx, 1 + nLarge + (iRow-iSmall)/nSize);
      }
    }
  }
}
#define ntileFinalizeFunc ntileValueFunc

/*
** Context object for last_value() window function.
*/
struct LastValueCtx {
  sqlite3_value *pVal;
  int nVal;

      sqlite3_value_free(p->pVal);
      p->pVal = 0;
    }
  }
}
static void last_valueValueFunc(sqlite3_context *pCtx){
  struct LastValueCtx *p;
  p = (struct LastValueCtx*)sqlite3_aggregate_context(pCtx, 0);
  if( p && p->pVal ){
    sqlite3_result_value(pCtx, p->pVal);
  }
}
static void last_valueFinalizeFunc(sqlite3_context *pCtx){
  struct LastValueCtx *p;
  p = (struct LastValueCtx*)sqlite3_aggregate_context(pCtx, sizeof(*p));

** Register those built-in window functions that are not also aggregates.
*/
SQLITE_PRIVATE void sqlite3WindowFunctions(void){
  static FuncDef aWindowFuncs[] = {
    WINDOWFUNCX(row_number, 0, 0),
    WINDOWFUNCX(dense_rank, 0, 0),
    WINDOWFUNCX(rank, 0, 0),
    WINDOWFUNCALL(percent_rank, 0, 0),
    WINDOWFUNCALL(cume_dist, 0, 0),
    WINDOWFUNCALL(ntile, 1, 0),
    WINDOWFUNCALL(last_value, 1, 0),
    WINDOWFUNCALL(nth_value, 2, 0),
    WINDOWFUNCALL(first_value, 1, 0),
    WINDOWFUNCNOOP(lead, 1, 0),
    WINDOWFUNCNOOP(lead, 2, 0),
    WINDOWFUNCNOOP(lead, 3, 0),
    WINDOWFUNCNOOP(lag, 1, 0),
    WINDOWFUNCNOOP(lag, 2, 0),
    WINDOWFUNCNOOP(lag, 3, 0),
  };
  sqlite3InsertBuiltinFuncs(aWindowFuncs, ArraySize(aWindowFuncs));
}

static Window *windowFind(Parse *pParse, Window *pList, const char *zName){
  Window *p;
  for(p=pList; p; p=p->pNextWin){
    if( sqlite3StrICmp(p->zName, zName)==0 ) break;
  }
  if( p==0 ){
    sqlite3ErrorMsg(pParse, "no such window: %s", zName);
  }
  return p;
}

/*
** This function is called immediately after resolving the function name
** for a window function within a SELECT statement. Argument pList is a
** linked list of WINDOW definitions for the current SELECT statement.
** Argument pFunc is the function definition just resolved and pWin
** is the Window object representing the associated OVER clause. This

*/
SQLITE_PRIVATE void sqlite3WindowUpdate(
  Parse *pParse, 
  Window *pList,                  /* List of named windows for this SELECT */
  Window *pWin,                   /* Window frame to update */
  FuncDef *pFunc                  /* Window function definition */
){
  if( pWin->zName && pWin->eFrmType==0 ){
    Window *p = windowFind(pParse, pList, pWin->zName);



    if( p==0 ) return;



    pWin->pPartition = sqlite3ExprListDup(pParse->db, p->pPartition, 0);
    pWin->pOrderBy = sqlite3ExprListDup(pParse->db, p->pOrderBy, 0);
    pWin->pStart = sqlite3ExprDup(pParse->db, p->pStart, 0);
    pWin->pEnd = sqlite3ExprDup(pParse->db, p->pEnd, 0);
    pWin->eStart = p->eStart;
    pWin->eEnd = p->eEnd;
    pWin->eFrmType = p->eFrmType;
    pWin->eExclude = p->eExclude;
  }else{
    sqlite3WindowChain(pParse, pWin, pList);
  }
  if( (pWin->eFrmType==TK_RANGE)
   && (pWin->pStart || pWin->pEnd) 
   && (pWin->pOrderBy==0 || pWin->pOrderBy->nExpr!=1)
  ){
    sqlite3ErrorMsg(pParse, 
      "RANGE with offset PRECEDING/FOLLOWING requires one ORDER BY expression"
    );
  }else
  if( pFunc->funcFlags & SQLITE_FUNC_WINDOW ){
    sqlite3 *db = pParse->db;
    if( pWin->pFilter ){
      sqlite3ErrorMsg(pParse, 
          "FILTER clause may only be used with aggregate window functions"
      );
    }else{
      struct WindowUpdate {
        const char *zFunc;
        int eFrmType;
        int eStart;
        int eEnd;
      } aUp[] = {
        { row_numberName,   TK_ROWS,   TK_UNBOUNDED, TK_CURRENT }, 
        { dense_rankName,   TK_RANGE,  TK_UNBOUNDED, TK_CURRENT }, 
        { rankName,         TK_RANGE,  TK_UNBOUNDED, TK_CURRENT }, 
        { percent_rankName, TK_GROUPS, TK_CURRENT,   TK_UNBOUNDED }, 
        { cume_distName,    TK_GROUPS, TK_FOLLOWING, TK_UNBOUNDED }, 
        { ntileName,        TK_ROWS,   TK_CURRENT,   TK_UNBOUNDED }, 
        { leadName,         TK_ROWS,   TK_UNBOUNDED, TK_UNBOUNDED }, 
        { lagName,          TK_ROWS,   TK_UNBOUNDED, TK_CURRENT }, 
      };
      int i;
      for(i=0; i<ArraySize(aUp); i++){
        if( pFunc->zName==aUp[i].zFunc ){


          sqlite3ExprDelete(db, pWin->pStart);
          sqlite3ExprDelete(db, pWin->pEnd);
          pWin->pEnd = pWin->pStart = 0;
          pWin->eFrmType = aUp[i].eFrmType;
          pWin->eStart = aUp[i].eStart;
          pWin->eEnd = aUp[i].eEnd;
          pWin->eExclude = 0;
          if( pWin->eStart==TK_FOLLOWING ){
            pWin->pStart = sqlite3Expr(db, TK_INTEGER, "1");
          }
          break;
        }
      }
    }
  }
  pWin->pFunc = pFunc;
}

/*
** Context object passed through sqlite3WalkExprList() to

      }
    }

    /* Assign a cursor number for the ephemeral table used to buffer rows.
    ** The OpenEphemeral instruction is coded later, after it is known how
    ** many columns the table will have.  */
    pMWin->iEphCsr = pParse->nTab++;
    pParse->nTab += 3;

    selectWindowRewriteEList(pParse, pMWin, pSrc, p->pEList, &pSublist);
    selectWindowRewriteEList(pParse, pMWin, pSrc, p->pOrderBy, &pSublist);
    pMWin->nBufferCol = (pSublist ? pSublist->nExpr : 0);

    /* Append the PARTITION BY and ORDER BY expressions to the to the 
    ** sub-select expression list. They are required to figure out where 

      }else{
        pSub->selFlags |= SF_Expanded;
        p->selFlags &= ~SF_Aggregate;
        sqlite3SelectPrep(pParse, pSub, 0);
      }

      sqlite3VdbeAddOp2(v, OP_OpenEphemeral, pMWin->iEphCsr, pSublist->nExpr);
      sqlite3VdbeAddOp2(v, OP_OpenDup, pMWin->iEphCsr+1, pMWin->iEphCsr);
      sqlite3VdbeAddOp2(v, OP_OpenDup, pMWin->iEphCsr+2, pMWin->iEphCsr);
      sqlite3VdbeAddOp2(v, OP_OpenDup, pMWin->iEphCsr+3, pMWin->iEphCsr);
    }else{
      sqlite3SelectDelete(db, pSub);
    }
    if( db->mallocFailed ) rc = SQLITE_NOMEM;
  }

  return rc;
}

/*
** Free the Window object passed as the second argument.
*/
SQLITE_PRIVATE void sqlite3WindowDelete(sqlite3 *db, Window *p){
  if( p ){
    sqlite3ExprDelete(db, p->pFilter);
    sqlite3ExprListDelete(db, p->pPartition);
    sqlite3ExprListDelete(db, p->pOrderBy);
    sqlite3ExprDelete(db, p->pEnd);
    sqlite3ExprDelete(db, p->pStart);
    sqlite3DbFree(db, p->zName);
    sqlite3DbFree(db, p->zBase);
    sqlite3DbFree(db, p);
  }
}

/*
** Free the linked list of Window objects starting at the second argument.
*/

}

/*
** Allocate and return a new Window object describing a Window Definition.
*/
SQLITE_PRIVATE Window *sqlite3WindowAlloc(
  Parse *pParse,    /* Parsing context */
  int eType,        /* Frame type. TK_RANGE, TK_ROWS, TK_GROUPS, or 0 */
  int eStart,       /* Start type: CURRENT, PRECEDING, FOLLOWING, UNBOUNDED */
  Expr *pStart,     /* Start window size if TK_PRECEDING or FOLLOWING */
  int eEnd,         /* End type: CURRENT, FOLLOWING, TK_UNBOUNDED, PRECEDING */
  Expr *pEnd,       /* End window size if TK_FOLLOWING or PRECEDING */
  u8 eExclude       /* EXCLUDE clause */
){
  Window *pWin = 0;
  int bImplicitFrame = 0;

  /* Parser assures the following: */
  assert( eType==0 || eType==TK_RANGE || eType==TK_ROWS || eType==TK_GROUPS );
  assert( eStart==TK_CURRENT || eStart==TK_PRECEDING
           || eStart==TK_UNBOUNDED || eStart==TK_FOLLOWING );
  assert( eEnd==TK_CURRENT || eEnd==TK_FOLLOWING
           || eEnd==TK_UNBOUNDED || eEnd==TK_PRECEDING );
  assert( (eStart==TK_PRECEDING || eStart==TK_FOLLOWING)==(pStart!=0) );
  assert( (eEnd==TK_FOLLOWING || eEnd==TK_PRECEDING)==(pEnd!=0) );

  if( eType==0 ){
    bImplicitFrame = 1;


    eType = TK_RANGE;


  }

  /* Additionally, the
  ** starting boundary type may not occur earlier in the following list than
  ** the ending boundary type:
  **
  **   UNBOUNDED PRECEDING
  **   <expr> PRECEDING
  **   CURRENT ROW
  **   <expr> FOLLOWING
  **   UNBOUNDED FOLLOWING
  **
  ** The parser ensures that "UNBOUNDED PRECEDING" cannot be used as an ending
  ** boundary, and than "UNBOUNDED FOLLOWING" cannot be used as a starting
  ** frame boundary.
  */
  if( (eStart==TK_CURRENT && eEnd==TK_PRECEDING)
   || (eStart==TK_FOLLOWING && (eEnd==TK_PRECEDING || eEnd==TK_CURRENT))
  ){
    sqlite3ErrorMsg(pParse, "unsupported frame specification");
    goto windowAllocErr;
  }

  pWin = (Window*)sqlite3DbMallocZero(pParse->db, sizeof(Window));
  if( pWin==0 ) goto windowAllocErr;
  pWin->eFrmType = eType;
  pWin->eStart = eStart;
  pWin->eEnd = eEnd;
  if( eExclude==0 && OptimizationDisabled(pParse->db, SQLITE_WindowFunc) ){
    eExclude = TK_NO;
  }
  pWin->eExclude = eExclude;
  pWin->bImplicitFrame = bImplicitFrame;
  pWin->pEnd = sqlite3WindowOffsetExpr(pParse, pEnd);
  pWin->pStart = sqlite3WindowOffsetExpr(pParse, pStart);
  return pWin;

windowAllocErr:
  sqlite3ExprDelete(pParse->db, pEnd);
  sqlite3ExprDelete(pParse->db, pStart);
  return 0;
}

/*
** Attach PARTITION and ORDER BY clauses pPartition and pOrderBy to window
** pWin. Also, if parameter pBase is not NULL, set pWin->zBase to the
** equivalent nul-terminated string.
*/
SQLITE_PRIVATE Window *sqlite3WindowAssemble(
  Parse *pParse, 
  Window *pWin, 
  ExprList *pPartition, 
  ExprList *pOrderBy, 
  Token *pBase
){
  if( pWin ){
    pWin->pPartition = pPartition;
    pWin->pOrderBy = pOrderBy;
    if( pBase ){
      pWin->zBase = sqlite3DbStrNDup(pParse->db, pBase->z, pBase->n);
    }
  }else{
    sqlite3ExprListDelete(pParse->db, pPartition);
    sqlite3ExprListDelete(pParse->db, pOrderBy);
  }
  return pWin;
}

/*
** Window *pWin has just been created from a WINDOW clause. Tokne pBase
** is the base window. Earlier windows from the same WINDOW clause are
** stored in the linked list starting at pWin->pNextWin. This function
** either updates *pWin according to the base specification, or else
** leaves an error in pParse.
*/
SQLITE_PRIVATE void sqlite3WindowChain(Parse *pParse, Window *pWin, Window *pList){
  if( pWin->zBase ){
    sqlite3 *db = pParse->db;
    Window *pExist = windowFind(pParse, pList, pWin->zBase);
    if( pExist ){
      const char *zErr = 0;
      /* Check for errors */
      if( pWin->pPartition ){
        zErr = "PARTITION clause";
      }else if( pExist->pOrderBy && pWin->pOrderBy ){
        zErr = "ORDER BY clause";
      }else if( pExist->bImplicitFrame==0 ){
        zErr = "frame specification";
      }
      if( zErr ){
        sqlite3ErrorMsg(pParse, 
            "cannot override %s of window: %s", zErr, pWin->zBase
        );
      }else{
        pWin->pPartition = sqlite3ExprListDup(db, pExist->pPartition, 0);
        if( pExist->pOrderBy ){
          assert( pWin->pOrderBy==0 );
          pWin->pOrderBy = sqlite3ExprListDup(db, pExist->pOrderBy, 0);
        }
        sqlite3DbFree(db, pWin->zBase);
        pWin->zBase = 0;
      }
    }
  }
}

/*
** Attach window object pWin to expression p.
*/
SQLITE_PRIVATE void sqlite3WindowAttach(Parse *pParse, Expr *p, Window *pWin){
  if( p ){
    assert( p->op==TK_FUNCTION );

}

/*
** Return 0 if the two window objects are identical, or non-zero otherwise.
** Identical window objects can be processed in a single scan.
*/
SQLITE_PRIVATE int sqlite3WindowCompare(Parse *pParse, Window *p1, Window *p2){
  if( p1->eFrmType!=p2->eFrmType ) return 1;
  if( p1->eStart!=p2->eStart ) return 1;
  if( p1->eEnd!=p2->eEnd ) return 1;
  if( p1->eExclude!=p2->eExclude ) return 1;
  if( sqlite3ExprCompare(pParse, p1->pStart, p2->pStart, -1) ) return 1;
  if( sqlite3ExprCompare(pParse, p1->pEnd, p2->pEnd, -1) ) return 1;
  if( sqlite3ExprListCompare(p1->pPartition, p2->pPartition, -1) ) return 1;
  if( sqlite3ExprListCompare(p1->pOrderBy, p2->pOrderBy, -1) ) return 1;
  return 0;
}


/*
** This is called by code in select.c before it calls sqlite3WhereBegin()
** to begin iterating through the sub-query results. It is used to allocate
** and initialize registers and cursors used by sqlite3WindowCodeStep().
*/
SQLITE_PRIVATE void sqlite3WindowCodeInit(Parse *pParse, Window *pMWin){
  Window *pWin;
  Vdbe *v = sqlite3GetVdbe(pParse);

  /* Allocate registers to use for PARTITION BY values, if any. Initialize
  ** said registers to NULL.  */
  if( pMWin->pPartition ){
    int nExpr = pMWin->pPartition->nExpr;
    pMWin->regPart = pParse->nMem+1;
    pParse->nMem += nExpr;
    sqlite3VdbeAddOp3(v, OP_Null, 0, pMWin->regPart, pMWin->regPart+nExpr-1);
  }

  pMWin->regOne = ++pParse->nMem;
  sqlite3VdbeAddOp2(v, OP_Integer, 1, pMWin->regOne);

  if( pMWin->eExclude ){
    pMWin->regStartRowid = ++pParse->nMem;
    pMWin->regEndRowid = ++pParse->nMem;
    pMWin->csrApp = pParse->nTab++;
    sqlite3VdbeAddOp2(v, OP_Integer, 1, pMWin->regStartRowid);
    sqlite3VdbeAddOp2(v, OP_Integer, 0, pMWin->regEndRowid);
    sqlite3VdbeAddOp2(v, OP_OpenDup, pMWin->csrApp, pMWin->iEphCsr);
    return;
  }

  for(pWin=pMWin; pWin; pWin=pWin->pNextWin){
    FuncDef *p = pWin->pFunc;
    if( (p->funcFlags & SQLITE_FUNC_MINMAX) && pWin->eStart!=TK_UNBOUNDED ){
      /* The inline versions of min() and max() require a single ephemeral
      ** table and 3 registers. The registers are used as follows:

      sqlite3VdbeAddOp2(v, OP_OpenEphemeral, pWin->csrApp, 2);
      sqlite3VdbeAppendP4(v, pKeyInfo, P4_KEYINFO);
      sqlite3VdbeAddOp2(v, OP_Integer, 0, pWin->regApp+1);
    }
    else if( p->zName==nth_valueName || p->zName==first_valueName ){
      /* Allocate two registers at pWin->regApp. These will be used to
      ** store the start and end index of the current frame.  */

      pWin->regApp = pParse->nMem+1;
      pWin->csrApp = pParse->nTab++;
      pParse->nMem += 2;
      sqlite3VdbeAddOp2(v, OP_OpenDup, pWin->csrApp, pMWin->iEphCsr);
    }
    else if( p->zName==leadName || p->zName==lagName ){

      pWin->csrApp = pParse->nTab++;
      sqlite3VdbeAddOp2(v, OP_OpenDup, pWin->csrApp, pMWin->iEphCsr);
    }
  }
}

#define WINDOW_STARTING_INT  0
#define WINDOW_ENDING_INT    1
#define WINDOW_NTH_VALUE_INT 2
#define WINDOW_STARTING_NUM  3
#define WINDOW_ENDING_NUM    4

/*
** A "PRECEDING <expr>" (eCond==0) or "FOLLOWING <expr>" (eCond==1) or the
** value of the second argument to nth_value() (eCond==2) has just been
** evaluated and the result left in register reg. This function generates VM
** code to check that the value is a non-negative integer and throws an
** exception if it is not.
*/
static void windowCheckValue(Parse *pParse, int reg, int eCond){
  static const char *azErr[] = {
    "frame starting offset must be a non-negative integer",
    "frame ending offset must be a non-negative integer",
    "second argument to nth_value must be a positive integer",
    "frame starting offset must be a non-negative number",
    "frame ending offset must be a non-negative number",
  };
  static int aOp[] = { OP_Ge, OP_Ge, OP_Gt, OP_Ge, OP_Ge };
  Vdbe *v = sqlite3GetVdbe(pParse);
  int regZero = sqlite3GetTempReg(pParse);
  assert( eCond>=0 && eCond<ArraySize(azErr) );
  sqlite3VdbeAddOp2(v, OP_Integer, 0, regZero);
  if( eCond>=WINDOW_STARTING_NUM ){
    int regString = sqlite3GetTempReg(pParse);
    sqlite3VdbeAddOp4(v, OP_String8, 0, regString, 0, "", P4_STATIC);
    sqlite3VdbeAddOp3(v, OP_Ge, regString, sqlite3VdbeCurrentAddr(v)+2, reg);
    sqlite3VdbeChangeP5(v, SQLITE_AFF_NUMERIC|SQLITE_JUMPIFNULL);
    VdbeCoverage(v);
    assert( eCond==3 || eCond==4 );
    VdbeCoverageIf(v, eCond==3);
    VdbeCoverageIf(v, eCond==4);
  }else{
    sqlite3VdbeAddOp2(v, OP_MustBeInt, reg, sqlite3VdbeCurrentAddr(v)+2);
    VdbeCoverage(v);
    assert( eCond==0 || eCond==1 || eCond==2 );
    VdbeCoverageIf(v, eCond==0);
    VdbeCoverageIf(v, eCond==1);
    VdbeCoverageIf(v, eCond==2);
  }
  sqlite3VdbeAddOp3(v, aOp[eCond], regZero, sqlite3VdbeCurrentAddr(v)+2, reg);
  VdbeCoverageNeverNullIf(v, eCond==0); /* NULL case captured by */
  VdbeCoverageNeverNullIf(v, eCond==1); /*   the OP_MustBeInt */
  VdbeCoverageNeverNullIf(v, eCond==2);
  VdbeCoverageNeverNullIf(v, eCond==3); /* NULL case caught by */
  VdbeCoverageNeverNullIf(v, eCond==4); /*   the OP_Ge */
  sqlite3MayAbort(pParse);
  sqlite3VdbeAddOp2(v, OP_Halt, SQLITE_ERROR, OE_Abort);
  sqlite3VdbeAppendP4(v, (void*)azErr[eCond], P4_STATIC);
  sqlite3ReleaseTempReg(pParse, regZero);
}

/*

** number of rows in the current partition.
*/
static void windowAggStep(
  Parse *pParse, 
  Window *pMWin,                  /* Linked list of window functions */
  int csr,                        /* Read arguments from this cursor */
  int bInverse,                   /* True to invoke xInverse instead of xStep */
  int reg                         /* Array of registers */

){
  Vdbe *v = sqlite3GetVdbe(pParse);
  Window *pWin;
  for(pWin=pMWin; pWin; pWin=pWin->pNextWin){
    FuncDef *pFunc = pWin->pFunc;
    int regArg;
    int nArg = windowArgCount(pWin);


    int i;

    for(i=0; i<nArg; i++){
      if( i!=1 || pFunc->zName!=nth_valueName ){
        sqlite3VdbeAddOp3(v, OP_Column, csr, pWin->iArgCol+i, reg+i);





      }else{
        sqlite3VdbeAddOp3(v, OP_Column, pMWin->iEphCsr, pWin->iArgCol+i, reg+i);
      }

    }


    regArg = reg;

    if( pMWin->regStartRowid==0
     && (pFunc->funcFlags & SQLITE_FUNC_MINMAX) 
     && (pWin->eStart!=TK_UNBOUNDED)
    ){
      int addrIsNull = sqlite3VdbeAddOp1(v, OP_IsNull, regArg);
      VdbeCoverage(v);
      if( bInverse==0 ){
        sqlite3VdbeAddOp2(v, OP_AddImm, pWin->regApp+1, 1);
        sqlite3VdbeAddOp2(v, OP_SCopy, regArg, pWin->regApp);
        sqlite3VdbeAddOp3(v, OP_MakeRecord, pWin->regApp, 2, pWin->regApp+2);
        sqlite3VdbeAddOp2(v, OP_IdxInsert, pWin->csrApp, pWin->regApp+2);
      }else{
        sqlite3VdbeAddOp4Int(v, OP_SeekGE, pWin->csrApp, 0, regArg, 1);
        VdbeCoverageNeverTaken(v);
        sqlite3VdbeAddOp1(v, OP_Delete, pWin->csrApp);
        sqlite3VdbeJumpHere(v, sqlite3VdbeCurrentAddr(v)-2);
      }
      sqlite3VdbeJumpHere(v, addrIsNull);
    }else if( pWin->regApp ){
      assert( pFunc->zName==nth_valueName
           || pFunc->zName==first_valueName
      );
      assert( bInverse==0 || bInverse==1 );
      sqlite3VdbeAddOp2(v, OP_AddImm, pWin->regApp+1-bInverse, 1);
    }else if( pFunc->xSFunc!=noopStepFunc ){




      int addrIf = 0;
      if( pWin->pFilter ){
        int regTmp;
        assert( nArg==0 || nArg==pWin->pOwner->x.pList->nExpr );
        assert( nArg || pWin->pOwner->x.pList==0 );

        regTmp = sqlite3GetTempReg(pParse);
        sqlite3VdbeAddOp3(v, OP_Column, csr, pWin->iArgCol+nArg,regTmp);



        addrIf = sqlite3VdbeAddOp3(v, OP_IfNot, regTmp, 0, 1);
        VdbeCoverage(v);

        sqlite3ReleaseTempReg(pParse, regTmp);
      }

      if( pFunc->funcFlags & SQLITE_FUNC_NEEDCOLL ){
        CollSeq *pColl;
        assert( nArg>0 );
        pColl = sqlite3ExprNNCollSeq(pParse, pWin->pOwner->x.pList->a[0].pExpr);
        sqlite3VdbeAddOp4(v, OP_CollSeq, 0,0,0, (const char*)pColl, P4_COLLSEQ);
      }
      sqlite3VdbeAddOp3(v, bInverse? OP_AggInverse : OP_AggStep, 
                        bInverse, regArg, pWin->regAccum);
      sqlite3VdbeAppendP4(v, pFunc, P4_FUNCDEF);
      sqlite3VdbeChangeP5(v, (u8)nArg);
      if( addrIf ) sqlite3VdbeJumpHere(v, addrIf);
    }
  }
}

typedef struct WindowCodeArg WindowCodeArg;
typedef struct WindowCsrAndReg WindowCsrAndReg;
struct WindowCsrAndReg {
  int csr;
  int reg;
};

struct WindowCodeArg {
  Parse *pParse;
  Window *pMWin;
  Vdbe *pVdbe;
  int regGosub;
  int addrGosub;
  int regArg;
  int eDelete;

  WindowCsrAndReg start;
  WindowCsrAndReg current;
  WindowCsrAndReg end;
};

/*
** Values that may be passed as the second argument to windowCodeOp().
*/
#define WINDOW_RETURN_ROW 1
#define WINDOW_AGGINVERSE 2
#define WINDOW_AGGSTEP    3

/*
** Generate VM code to read the window frames peer values from cursor csr into
** an array of registers starting at reg.
*/
static void windowReadPeerValues(
  WindowCodeArg *p,
  int csr,
  int reg
){
  Window *pMWin = p->pMWin;
  ExprList *pOrderBy = pMWin->pOrderBy;
  if( pOrderBy ){
    Vdbe *v = sqlite3GetVdbe(p->pParse);
    ExprList *pPart = pMWin->pPartition;
    int iColOff = pMWin->nBufferCol + (pPart ? pPart->nExpr : 0);
    int i;
    for(i=0; i<pOrderBy->nExpr; i++){
      sqlite3VdbeAddOp3(v, OP_Column, csr, iColOff+i, reg+i);
    }
  }
}

/*
** Generate VM code to invoke either xValue() (bFin==0) or xFinalize()
** (bFin==1) for each window function in the linked list starting at
** pMWin. Or, for built-in window-functions that do not use the standard
** API, generate the equivalent VM code.
*/
static void windowAggFinal(WindowCodeArg *p, int bFin){
  Parse *pParse = p->pParse;
  Window *pMWin = p->pMWin;
  Vdbe *v = sqlite3GetVdbe(pParse);
  Window *pWin;

  for(pWin=pMWin; pWin; pWin=pWin->pNextWin){
    if( pMWin->regStartRowid==0
     && (pWin->pFunc->funcFlags & SQLITE_FUNC_MINMAX) 
     && (pWin->eStart!=TK_UNBOUNDED)
    ){
      sqlite3VdbeAddOp2(v, OP_Null, 0, pWin->regResult);
      sqlite3VdbeAddOp1(v, OP_Last, pWin->csrApp);
      VdbeCoverage(v);
      sqlite3VdbeAddOp3(v, OP_Column, pWin->csrApp, 0, pWin->regResult);
      sqlite3VdbeJumpHere(v, sqlite3VdbeCurrentAddr(v)-2);



    }else if( pWin->regApp ){
      assert( pMWin->regStartRowid==0 );
    }else{
      int nArg = windowArgCount(pWin);
      if( bFin ){
        sqlite3VdbeAddOp2(v, OP_AggFinal, pWin->regAccum, nArg);
        sqlite3VdbeAppendP4(v, pWin->pFunc, P4_FUNCDEF);
        sqlite3VdbeAddOp2(v, OP_Copy, pWin->regAccum, pWin->regResult);
        sqlite3VdbeAddOp2(v, OP_Null, 0, pWin->regAccum);
      }else{
        sqlite3VdbeAddOp3(v, OP_AggValue,pWin->regAccum,nArg,pWin->regResult);

        sqlite3VdbeAppendP4(v, pWin->pFunc, P4_FUNCDEF);
      }
    }
  }
}

/*
** Generate code to calculate the current values of all window functions in the
** p->pMWin list by doing a full scan of the current window frame. Store the
** results in the Window.regResult registers, ready to return the upper
** layer.
*/
static void windowFullScan(WindowCodeArg *p){
  Window *pWin;
  Parse *pParse = p->pParse;






  Window *pMWin = p->pMWin;
  Vdbe *v = p->pVdbe;

  int regCRowid = 0;              /* Current rowid value */
  int regCPeer = 0;               /* Current peer values */
  int regRowid = 0;               /* AggStep rowid value */
  int regPeer = 0;                /* AggStep peer values */

  int nPeer;
  int lblNext;
  int lblBrk;
  int addrNext;
  int csr = pMWin->csrApp;

  nPeer = (pMWin->pOrderBy ? pMWin->pOrderBy->nExpr : 0);

  lblNext = sqlite3VdbeMakeLabel(pParse);
  lblBrk = sqlite3VdbeMakeLabel(pParse);

  regCRowid = sqlite3GetTempReg(pParse);
  regRowid = sqlite3GetTempReg(pParse);
  if( nPeer ){
    regCPeer = sqlite3GetTempRange(pParse, nPeer);
    regPeer = sqlite3GetTempRange(pParse, nPeer);
  }






  sqlite3VdbeAddOp2(v, OP_Rowid, pMWin->iEphCsr, regCRowid);
  windowReadPeerValues(p, pMWin->iEphCsr, regCPeer);

  for(pWin=pMWin; pWin; pWin=pWin->pNextWin){
    sqlite3VdbeAddOp2(v, OP_Null, 0, pWin->regAccum);
  }

  sqlite3VdbeAddOp3(v, OP_SeekGE, csr, lblBrk, pMWin->regStartRowid);
  VdbeCoverage(v);
  addrNext = sqlite3VdbeCurrentAddr(v);
  sqlite3VdbeAddOp2(v, OP_Rowid, csr, regRowid);
  sqlite3VdbeAddOp3(v, OP_Gt, pMWin->regEndRowid, lblBrk, regRowid);
  VdbeCoverageNeverNull(v);

  if( pMWin->eExclude==TK_CURRENT ){
    sqlite3VdbeAddOp3(v, OP_Eq, regCRowid, lblNext, regRowid);
    VdbeCoverageNeverNull(v);
  }else if( pMWin->eExclude!=TK_NO ){
    int addr;
    int addrEq = 0;
    KeyInfo *pKeyInfo = 0;

    if( pMWin->pOrderBy ){
      pKeyInfo = sqlite3KeyInfoFromExprList(pParse, pMWin->pOrderBy, 0, 0);
    }
    if( pMWin->eExclude==TK_TIES ){
      addrEq = sqlite3VdbeAddOp3(v, OP_Eq, regCRowid, 0, regRowid);
      VdbeCoverageNeverNull(v);
    }
    if( pKeyInfo ){
      windowReadPeerValues(p, csr, regPeer);
      sqlite3VdbeAddOp3(v, OP_Compare, regPeer, regCPeer, nPeer);
      sqlite3VdbeAppendP4(v, (void*)pKeyInfo, P4_KEYINFO);
      addr = sqlite3VdbeCurrentAddr(v)+1;
      sqlite3VdbeAddOp3(v, OP_Jump, addr, lblNext, addr);
      VdbeCoverageEqNe(v);

    }else{
      sqlite3VdbeAddOp2(v, OP_Goto, 0, lblNext);
    }
    if( addrEq ) sqlite3VdbeJumpHere(v, addrEq);
  }

  windowAggStep(pParse, pMWin, csr, 0, p->regArg);

  sqlite3VdbeResolveLabel(v, lblNext);
  sqlite3VdbeAddOp2(v, OP_Next, csr, addrNext);
  VdbeCoverage(v);
  sqlite3VdbeJumpHere(v, addrNext-1);
  sqlite3VdbeJumpHere(v, addrNext+1);
  sqlite3ReleaseTempReg(pParse, regRowid);
  sqlite3ReleaseTempReg(pParse, regCRowid);
  if( nPeer ){
    sqlite3ReleaseTempRange(pParse, regPeer, nPeer);
    sqlite3ReleaseTempRange(pParse, regCPeer, nPeer);
  }






  windowAggFinal(p, 1);
}

/*
** Invoke the sub-routine at regGosub (generated by code in select.c) to
** return the current row of Window.iEphCsr. If all window functions are
** aggregate window functions that use the standard API, a single
** OP_Gosub instruction is all that this routine generates. Extra VM code
** for per-row processing is only generated for the following built-in window
** functions:
**
**   nth_value()
**   first_value()
**   lag()
**   lead()
*/
static void windowReturnOneRow(WindowCodeArg *p){

  Window *pMWin = p->pMWin;
  Vdbe *v = p->pVdbe;

  if( pMWin->regStartRowid ){
    windowFullScan(p);
  }else{
    Parse *pParse = p->pParse;
    Window *pWin;

    for(pWin=pMWin; pWin; pWin=pWin->pNextWin){
      FuncDef *pFunc = pWin->pFunc;
      if( pFunc->zName==nth_valueName
       || pFunc->zName==first_valueName
      ){
        int csr = pWin->csrApp;
        int lbl = sqlite3VdbeMakeLabel(pParse);
        int tmpReg = sqlite3GetTempReg(pParse);
        sqlite3VdbeAddOp2(v, OP_Null, 0, pWin->regResult);
  
        if( pFunc->zName==nth_valueName ){
          sqlite3VdbeAddOp3(v, OP_Column,pMWin->iEphCsr,pWin->iArgCol+1,tmpReg);
          windowCheckValue(pParse, tmpReg, 2);
        }else{
          sqlite3VdbeAddOp2(v, OP_Integer, 1, tmpReg);
        }
        sqlite3VdbeAddOp3(v, OP_Add, tmpReg, pWin->regApp, tmpReg);
        sqlite3VdbeAddOp3(v, OP_Gt, pWin->regApp+1, lbl, tmpReg);
        VdbeCoverageNeverNull(v);
        sqlite3VdbeAddOp3(v, OP_SeekRowid, csr, 0, tmpReg);
        VdbeCoverageNeverTaken(v);
        sqlite3VdbeAddOp3(v, OP_Column, csr, pWin->iArgCol, pWin->regResult);
        sqlite3VdbeResolveLabel(v, lbl);
        sqlite3ReleaseTempReg(pParse, tmpReg);
      }
      else if( pFunc->zName==leadName || pFunc->zName==lagName ){
        int nArg = pWin->pOwner->x.pList->nExpr;

        int csr = pWin->csrApp;
        int lbl = sqlite3VdbeMakeLabel(pParse);
        int tmpReg = sqlite3GetTempReg(pParse);
        int iEph = pMWin->iEphCsr;
  
        if( nArg<3 ){
          sqlite3VdbeAddOp2(v, OP_Null, 0, pWin->regResult);
        }else{
          sqlite3VdbeAddOp3(v, OP_Column, iEph,pWin->iArgCol+2,pWin->regResult);
        }
        sqlite3VdbeAddOp2(v, OP_Rowid, iEph, tmpReg);
        if( nArg<2 ){
          int val = (pFunc->zName==leadName ? 1 : -1);
          sqlite3VdbeAddOp2(v, OP_AddImm, tmpReg, val);
        }else{
          int op = (pFunc->zName==leadName ? OP_Add : OP_Subtract);
          int tmpReg2 = sqlite3GetTempReg(pParse);
          sqlite3VdbeAddOp3(v, OP_Column, iEph, pWin->iArgCol+1, tmpReg2);
          sqlite3VdbeAddOp3(v, op, tmpReg2, tmpReg, tmpReg);
          sqlite3ReleaseTempReg(pParse, tmpReg2);
        }
  
        sqlite3VdbeAddOp3(v, OP_SeekRowid, csr, lbl, tmpReg);
        VdbeCoverage(v);
        sqlite3VdbeAddOp3(v, OP_Column, csr, pWin->iArgCol, pWin->regResult);
        sqlite3VdbeResolveLabel(v, lbl);
        sqlite3ReleaseTempReg(pParse, tmpReg);
      }
    }

  }






























  sqlite3VdbeAddOp2(v, OP_Gosub, p->regGosub, p->addrGosub);







}

/*
** Generate code to set the accumulator register for each window function
** in the linked list passed as the second argument to NULL. And perform
** any equivalent initialization required by any built-in window functions
** in the list.
*/
static int windowInitAccum(Parse *pParse, Window *pMWin){
  Vdbe *v = sqlite3GetVdbe(pParse);
  int regArg;
  int nArg = 0;
  Window *pWin;
  for(pWin=pMWin; pWin; pWin=pWin->pNextWin){
    FuncDef *pFunc = pWin->pFunc;
    sqlite3VdbeAddOp2(v, OP_Null, 0, pWin->regAccum);
    nArg = MAX(nArg, windowArgCount(pWin));
    if( pMWin->regStartRowid==0 ){
      if( pFunc->zName==nth_valueName || pFunc->zName==first_valueName ){


        sqlite3VdbeAddOp2(v, OP_Integer, 0, pWin->regApp);
        sqlite3VdbeAddOp2(v, OP_Integer, 0, pWin->regApp+1);
      }

      if( (pFunc->funcFlags & SQLITE_FUNC_MINMAX) && pWin->csrApp ){
        assert( pWin->eStart!=TK_UNBOUNDED );
        sqlite3VdbeAddOp1(v, OP_ResetSorter, pWin->csrApp);
        sqlite3VdbeAddOp2(v, OP_Integer, 0, pWin->regApp+1);
      }
    }
  }
  regArg = pParse->nMem+1;
  pParse->nMem += nArg;
  return regArg;
}


/* 











** Return true if the current frame should be cached in the ephemeral table,
** even if there are no xInverse() calls required.

*/




static int windowCacheFrame(Window *pMWin){
  Window *pWin;










  if( pMWin->regStartRowid ) return 1;

  for(pWin=pMWin; pWin; pWin=pWin->pNextWin){







    FuncDef *pFunc = pWin->pFunc;


















    if( (pFunc->zName==nth_valueName)















     || (pFunc->zName==first_valueName)
     || (pFunc->zName==leadName)
     || (pFunc->zName==lagName)
    ){
      return 1;



    }
  }
  return 0;

}


/*
** regOld and regNew are each the first register in an array of size
** pOrderBy->nExpr. This function generates code to compare the two
** arrays of registers using the collation sequences and other comparison
** parameters specified by pOrderBy. 
**
** If the two arrays are not equal, the contents of regNew is copied to 
** regOld and control falls through. Otherwise, if the contents of the arrays
** are equal, an OP_Goto is executed. The address of the OP_Goto is returned.



























*/
static void windowIfNewPeer(
  Parse *pParse,
  ExprList *pOrderBy,
  int regNew,                     /* First in array of new values */
  int regOld,                     /* First in array of old values */


  int addr                        /* Jump here */
){

  Vdbe *v = sqlite3GetVdbe(pParse);



  if( pOrderBy ){

    int nVal = pOrderBy->nExpr;
    KeyInfo *pKeyInfo = sqlite3KeyInfoFromExprList(pParse, pOrderBy, 0, 0);







    sqlite3VdbeAddOp3(v, OP_Compare, regOld, regNew, nVal);
    sqlite3VdbeAppendP4(v, (void*)pKeyInfo, P4_KEYINFO);




    sqlite3VdbeAddOp3(v, OP_Jump, 
      sqlite3VdbeCurrentAddr(v)+1, addr, sqlite3VdbeCurrentAddr(v)+1
    );




    VdbeCoverageEqNe(v);
    sqlite3VdbeAddOp3(v, OP_Copy, regNew, regOld, nVal-1);

  }else{
    sqlite3VdbeAddOp2(v, OP_Goto, 0, addr);

  }


}



/*
** This function is called as part of generating VM programs for RANGE






** offset PRECEDING/FOLLOWING frame boundaries. Assuming "ASC" order for










** the ORDER BY term in the window, it generates code equivalent to:

**
**   if( csr1.peerVal + regVal >= csr2.peerVal ) goto lbl;


**
** A special type of arithmetic is used such that if csr.peerVal is not
** a numeric type (real or integer), then the result of the addition is
** a copy of csr1.peerVal.
*/








static void windowCodeRangeTest(


  WindowCodeArg *p, 
  int op,                          /* OP_Ge or OP_Gt */




  int csr1, 

  int regVal, 
  int csr2,
  int lbl
){






  Parse *pParse = p->pParse;



  Vdbe *v = sqlite3GetVdbe(pParse);

  int reg1 = sqlite3GetTempReg(pParse);




  int reg2 = sqlite3GetTempReg(pParse);




  int arith = OP_Add;

  int addrGe;




  int regString = ++pParse->nMem;
















  assert( op==OP_Ge || op==OP_Gt || op==OP_Le );
  assert( p->pMWin->pOrderBy && p->pMWin->pOrderBy->nExpr==1 );
  if( p->pMWin->pOrderBy->a[0].sortOrder ){

    switch( op ){








      case OP_Ge: op = OP_Le; break;
      case OP_Gt: op = OP_Lt; break;


      default: assert( op==OP_Le ); op = OP_Ge; break;
    }


    arith = OP_Subtract;
  }




  windowReadPeerValues(p, csr1, reg1);
  windowReadPeerValues(p, csr2, reg2);

  /* Check if the peer value for csr1 value is a text or blob by comparing
  ** it to the smallest possible string - ''. If it is, jump over the
  ** OP_Add or OP_Subtract operation and proceed directly to the comparison. */
  sqlite3VdbeAddOp4(v, OP_String8, 0, regString, 0, "", P4_STATIC);
  addrGe = sqlite3VdbeAddOp3(v, OP_Ge, regString, 0, reg1);
  VdbeCoverage(v);
  sqlite3VdbeAddOp3(v, arith, regVal, reg1, reg1);

  sqlite3VdbeJumpHere(v, addrGe);
  sqlite3VdbeAddOp3(v, op, reg2, lbl, reg1); VdbeCoverage(v);
  sqlite3VdbeChangeP5(v, SQLITE_NULLEQ);
  assert( op==OP_Ge || op==OP_Gt || op==OP_Lt || op==OP_Le );
  testcase(op==OP_Ge); VdbeCoverageIf(v, op==OP_Ge);
  testcase(op==OP_Lt); VdbeCoverageIf(v, op==OP_Lt);
  testcase(op==OP_Le); VdbeCoverageIf(v, op==OP_Le);
  testcase(op==OP_Gt); VdbeCoverageIf(v, op==OP_Gt);

  sqlite3ReleaseTempReg(pParse, reg1);
  sqlite3ReleaseTempReg(pParse, reg2);
}

































/*
** Helper function for sqlite3WindowCodeStep(). Each call to this function
** generates VM code for a single RETURN_ROW, AGGSTEP or AGGINVERSE 
** operation. Refer to the header comment for sqlite3WindowCodeStep() for
** details.
*/

static int windowCodeOp(
 WindowCodeArg *p,                /* Context object */
 int op,                          /* WINDOW_RETURN_ROW, AGGSTEP or AGGINVERSE */
 int regCountdown,                /* Register for OP_IfPos countdown */
 int jumpOnEof                    /* Jump here if stepped cursor reaches EOF */





){

  int csr, reg;
  Parse *pParse = p->pParse;
  Window *pMWin = p->pMWin;
  int ret = 0;





  Vdbe *v = p->pVdbe;



  int addrIf = 0; 


  int addrContinue = 0;
  int addrGoto = 0;







  int bPeer = (pMWin->eFrmType!=TK_ROWS);




































  int lblDone = sqlite3VdbeMakeLabel(pParse);

  int addrNextRange = 0;

  /* Special case - WINDOW_AGGINVERSE is always a no-op if the frame
  ** starts with UNBOUNDED PRECEDING. */
  if( op==WINDOW_AGGINVERSE && pMWin->eStart==TK_UNBOUNDED ){
    assert( regCountdown==0 && jumpOnEof==0 );
    return 0;
  }







  if( regCountdown>0 ){




    if( pMWin->eFrmType==TK_RANGE ){
      addrNextRange = sqlite3VdbeCurrentAddr(v);
      assert( op==WINDOW_AGGINVERSE || op==WINDOW_AGGSTEP );

      if( op==WINDOW_AGGINVERSE ){
        if( pMWin->eStart==TK_FOLLOWING ){

          windowCodeRangeTest(
              p, OP_Le, p->current.csr, regCountdown, p->start.csr, lblDone
          );
        }else{
          windowCodeRangeTest(
              p, OP_Ge, p->start.csr, regCountdown, p->current.csr, lblDone
          );


        }

      }else{

        windowCodeRangeTest(

            p, OP_Gt, p->end.csr, regCountdown, p->current.csr, lblDone
        );


      }


    }else{
      addrIf = sqlite3VdbeAddOp3(v, OP_IfPos, regCountdown, 0, 1);
      VdbeCoverage(v);

    }

  }







  if( op==WINDOW_RETURN_ROW && pMWin->regStartRowid==0 ){


    windowAggFinal(p, 0);




  }
  addrContinue = sqlite3VdbeCurrentAddr(v);
  switch( op ){

    case WINDOW_RETURN_ROW:
      csr = p->current.csr;














      reg = p->current.reg;
      windowReturnOneRow(p);



      break;

    case WINDOW_AGGINVERSE:
      csr = p->start.csr;
      reg = p->start.reg;
      if( pMWin->regStartRowid ){
        assert( pMWin->regEndRowid );
        sqlite3VdbeAddOp2(v, OP_AddImm, pMWin->regStartRowid, 1);
      }else{
        windowAggStep(pParse, pMWin, csr, 1, p->regArg);
      }
      break;



    default:
      assert( op==WINDOW_AGGSTEP );
      csr = p->end.csr;
      reg = p->end.reg;
      if( pMWin->regStartRowid ){
        assert( pMWin->regEndRowid );
        sqlite3VdbeAddOp2(v, OP_AddImm, pMWin->regEndRowid, 1);
      }else{
        windowAggStep(pParse, pMWin, csr, 0, p->regArg);

      }
      break;
  }





















































  if( op==p->eDelete ){


    sqlite3VdbeAddOp1(v, OP_Delete, csr);





    sqlite3VdbeChangeP5(v, OPFLAG_SAVEPOSITION);


  }


  if( jumpOnEof ){



    sqlite3VdbeAddOp2(v, OP_Next, csr, sqlite3VdbeCurrentAddr(v)+2);

    VdbeCoverage(v);



    ret = sqlite3VdbeAddOp0(v, OP_Goto);


  }else{





    sqlite3VdbeAddOp2(v, OP_Next, csr, sqlite3VdbeCurrentAddr(v)+1+bPeer);
    VdbeCoverage(v);

    if( bPeer ){
      addrGoto = sqlite3VdbeAddOp0(v, OP_Goto);
    }
  }


















  if( bPeer ){





    int nReg = (pMWin->pOrderBy ? pMWin->pOrderBy->nExpr : 0);

    int regTmp = (nReg ? sqlite3GetTempRange(pParse, nReg) : 0);
    windowReadPeerValues(p, csr, regTmp);

    windowIfNewPeer(pParse, pMWin->pOrderBy, regTmp, reg, addrContinue);
    sqlite3ReleaseTempRange(pParse, regTmp, nReg);
  }



  if( addrNextRange ){




    sqlite3VdbeAddOp2(v, OP_Goto, 0, addrNextRange);

  }
  sqlite3VdbeResolveLabel(v, lblDone);
  if( addrGoto ) sqlite3VdbeJumpHere(v, addrGoto);
  if( addrIf ) sqlite3VdbeJumpHere(v, addrIf);

  return ret;
}








/*
** Allocate and return a duplicate of the Window object indicated by the
** third argument. Set the Window.pOwner field of the new object to
** pOwner.
*/
SQLITE_PRIVATE Window *sqlite3WindowDup(sqlite3 *db, Expr *pOwner, Window *p){
  Window *pNew = 0;
  if( ALWAYS(p) ){
    pNew = sqlite3DbMallocZero(db, sizeof(Window));
    if( pNew ){
      pNew->zName = sqlite3DbStrDup(db, p->zName);
      pNew->pFilter = sqlite3ExprDup(db, p->pFilter, 0);
      pNew->pFunc = p->pFunc;
      pNew->pPartition = sqlite3ExprListDup(db, p->pPartition, 0);
      pNew->pOrderBy = sqlite3ExprListDup(db, p->pOrderBy, 0);
      pNew->eFrmType = p->eFrmType;
      pNew->eEnd = p->eEnd;
      pNew->eStart = p->eStart;
      pNew->eExclude = p->eExclude;
      pNew->pStart = sqlite3ExprDup(db, p->pStart, 0);
      pNew->pEnd = sqlite3ExprDup(db, p->pEnd, 0);
      pNew->pOwner = pOwner;
    }
  }
  return pNew;
}