text: /*
  ** 2001 September 15
  **
  ** The author disclaims copyright to this source code.  In place of
  ** a legal notice, here is a blessing:
  **
  **    May you do good and not evil.
  **    May you find forgiveness for yourself and forgive others.
  **    May you share freely, never taking more than you give.
  **
  *************************************************************************
  ** Internal interface definitions for SQLite.
  **
  ** @(#) $Id: sqliteInt.h,v 1.493 2006/04/04 01:54:55 drh Exp $
  */
  #ifndef _SQLITEINT_H_
  #define _SQLITEINT_H_
  
  #ifdef __cplusplus
  extern "C" {
  #endif
  /*
  ** Extra interface definitions for those who need them
  */
  #ifdef SQLITE_EXTRA
  # include "sqliteExtra.h"
  #endif
  
  /*
  ** Many people are failing to set -DNDEBUG=1 when compiling SQLite.
  ** Setting NDEBUG makes the code smaller and run faster.  So the following
  ** lines are added to automatically set NDEBUG unless the -DSQLITE_DEBUG=1
  ** option is set.  Thus NDEBUG becomes an opt-in rather than an opt-out
  ** feature.
  */
  #if !defined(NDEBUG) && !defined(SQLITE_DEBUG) 
  # define NDEBUG 1
  #endif
  
  /*
  ** These #defines should enable >2GB file support on Posix if the
  ** underlying operating system supports it.  If the OS lacks
  ** large file support, or if the OS is windows, these should be no-ops.
  **
  ** Large file support can be disabled using the -DSQLITE_DISABLE_LFS switch
  ** on the compiler command line.  This is necessary if you are compiling
  ** on a recent machine (ex: RedHat 7.2) but you want your code to work
  ** on an older machine (ex: RedHat 6.0).  If you compile on RedHat 7.2
  ** without this option, LFS is enable.  But LFS does not exist in the kernel
  ** in RedHat 6.0, so the code won't work.  Hence, for maximum binary
  ** portability you should omit LFS.
  **
  ** Similar is true for MacOS.  LFS is only supported on MacOS 9 and later.
  */
  #ifndef SQLITE_DISABLE_LFS
  # define _LARGE_FILE       1
  # ifndef _FILE_OFFSET_BITS
  #   define _FILE_OFFSET_BITS 64
  # endif
  # define _LARGEFILE_SOURCE 1
  #endif
  
  #include "sqlite3.h"
  #include "hash.h"
  #include "parse.h"
  #include <stdio.h>
  #include <stdlib.h>
  #include <string.h>
  #include <assert.h>
  #include <stddef.h>
  
  /*
  ** If compiling for a processor that lacks floating point support,
  ** substitute integer for floating-point
  */
  #ifdef SQLITE_OMIT_FLOATING_POINT
  # define double sqlite_int64
  # define LONGDOUBLE_TYPE sqlite_int64
  # ifndef SQLITE_BIG_DBL
  #   define SQLITE_BIG_DBL (0x7fffffffffffffff)
  # endif
  # define SQLITE_OMIT_DATETIME_FUNCS 1
  # define SQLITE_OMIT_TRACE 1
  #endif
  #ifndef SQLITE_BIG_DBL
  # define SQLITE_BIG_DBL (1e99)
  #endif
  
  /*
  ** The maximum number of in-memory pages to use for the main database
  ** table and for temporary tables. Internally, the MAX_PAGES and 
  ** TEMP_PAGES macros are used. To override the default values at
  ** compilation time, the SQLITE_DEFAULT_CACHE_SIZE and 
  ** SQLITE_DEFAULT_TEMP_CACHE_SIZE macros should be set.
  */
  #ifdef SQLITE_DEFAULT_CACHE_SIZE
  # define MAX_PAGES SQLITE_DEFAULT_CACHE_SIZE
  #else
  # define MAX_PAGES   2000
  #endif
  #ifdef SQLITE_DEFAULT_TEMP_CACHE_SIZE
  # define TEMP_PAGES SQLITE_DEFAULT_TEMP_CACHE_SIZE
  #else
  # define TEMP_PAGES   500
  #endif
  
  /*
  ** OMIT_TEMPDB is set to 1 if SQLITE_OMIT_TEMPDB is defined, or 0
  ** afterward. Having this macro allows us to cause the C compiler 
  ** to omit code used by TEMP tables without messy #ifndef statements.
  */
  #ifdef SQLITE_OMIT_TEMPDB
  #define OMIT_TEMPDB 1
  #else
  #define OMIT_TEMPDB 0
  #endif
  
  /*
  ** If the following macro is set to 1, then NULL values are considered
  ** distinct when determining whether or not two entries are the same
  ** in a UNIQUE index.  This is the way PostgreSQL, Oracle, DB2, MySQL,
  ** OCELOT, and Firebird all work.  The SQL92 spec explicitly says this
  ** is the way things are suppose to work.
  **
  ** If the following macro is set to 0, the NULLs are indistinct for
  ** a UNIQUE index.  In this mode, you can only have a single NULL entry
  ** for a column declared UNIQUE.  This is the way Informix and SQL Server
  ** work.
  */
  #define NULL_DISTINCT_FOR_UNIQUE 1
  
  /*
  ** The maximum number of attached databases.  This must be at least 2
  ** in order to support the main database file (0) and the file used to
  ** hold temporary tables (1).  And it must be less than 32 because
  ** we use a bitmask of databases with a u32 in places (for example
  ** the Parse.cookieMask field).
  */
  #define MAX_ATTACHED 10
  
  /*
  ** The maximum value of a ?nnn wildcard that the parser will accept.
  */
  #define SQLITE_MAX_VARIABLE_NUMBER 999
  
  /*
  ** The "file format" number is an integer that is incremented whenever
  ** the VDBE-level file format changes.  The following macros define the
  ** the default file format for new databases and the maximum file format
  ** that the library can read.
  */
  #define SQLITE_MAX_FILE_FORMAT 4
  #ifndef SQLITE_DEFAULT_FILE_FORMAT
  # define SQLITE_DEFAULT_FILE_FORMAT 4
  #endif
  
  /*
  ** Provide a default value for TEMP_STORE in case it is not specified
  ** on the command-line
  */
  #ifndef TEMP_STORE
  # define TEMP_STORE 1
  #endif
  
  /*
  ** GCC does not define the offsetof() macro so we'll have to do it
  ** ourselves.
  */
  #ifndef offsetof
  #define offsetof(STRUCTURE,FIELD) ((int)((char*)&((STRUCTURE*)0)->FIELD))
  #endif
  
  /*
  ** Check to see if this machine uses EBCDIC.  (Yes, believe it or
  ** not, there are still machines out there that use EBCDIC.)
  */
  #if 'A' == '\301'
  # define SQLITE_EBCDIC 1
  #else
  # define SQLITE_ASCII 1
  #endif
  
  /*
  ** Integers of known sizes.  These typedefs might change for architectures
  ** where the sizes very.  Preprocessor macros are available so that the
  ** types can be conveniently redefined at compile-type.  Like this:
  **
  **         cc '-DUINTPTR_TYPE=long long int' ...
  */
  #ifndef UINT32_TYPE
  # define UINT32_TYPE unsigned int
  #endif
  #ifndef UINT16_TYPE
  # define UINT16_TYPE unsigned short int
  #endif
  #ifndef INT16_TYPE
  # define INT16_TYPE short int
  #endif
  #ifndef UINT8_TYPE
  # define UINT8_TYPE unsigned char
  #endif
  #ifndef INT8_TYPE
  # define INT8_TYPE signed char
  #endif
  #ifndef LONGDOUBLE_TYPE
  # define LONGDOUBLE_TYPE long double
  #endif
  typedef sqlite_int64 i64;          /* 8-byte signed integer */
  typedef sqlite_uint64 u64;         /* 8-byte unsigned integer */
  typedef UINT32_TYPE u32;           /* 4-byte unsigned integer */
  typedef UINT16_TYPE u16;           /* 2-byte unsigned integer */
  typedef INT16_TYPE i16;            /* 2-byte signed integer */
  typedef UINT8_TYPE u8;             /* 1-byte unsigned integer */
  typedef UINT8_TYPE i8;             /* 1-byte signed integer */
  
  /*
  ** Macros to determine whether the machine is big or little endian,
  ** evaluated at runtime.
  */
  extern const int sqlite3one;
  #define SQLITE_BIGENDIAN    (*(char *)(&sqlite3one)==0)
  #define SQLITE_LITTLEENDIAN (*(char *)(&sqlite3one)==1)
  
  /*
  ** An instance of the following structure is used to store the busy-handler
  ** callback for a given sqlite handle. 
  **
  ** The sqlite.busyHandler member of the sqlite struct contains the busy
  ** callback for the database handle. Each pager opened via the sqlite
  ** handle is passed a pointer to sqlite.busyHandler. The busy-handler
  ** callback is currently invoked only from within pager.c.
  */
  typedef struct BusyHandler BusyHandler;
  struct BusyHandler {
    int (*xFunc)(void *,int);  /* The busy callback */
    void *pArg;                /* First arg to busy callback */
    int nBusy;                 /* Incremented with each busy call */
  };
  
  /*
  ** Defer sourcing vdbe.h and btree.h until after the "u8" and 
  ** "BusyHandler typedefs.
  */
  //#include "vdbe.h"
  //#include "btree.h"
  //#include "pager.h"
  
  #ifdef SQLITE_MEMDEBUG
  /*
  ** The following global variables are used for testing and debugging
  ** only.  They only work if SQLITE_MEMDEBUG is defined.
  */
  extern int sqlite3_nMalloc;      /* Number of sqliteMalloc() calls */
  extern int sqlite3_nFree;        /* Number of sqliteFree() calls */
  extern int sqlite3_iMallocFail;  /* Fail sqliteMalloc() after this many calls */
  extern int sqlite3_iMallocReset; /* Set iMallocFail to this when it reaches 0 */
  
  extern void *sqlite3_pFirst;         /* Pointer to linked list of allocations */
  extern int sqlite3_nMaxAlloc;        /* High water mark of ThreadData.nAlloc */
  extern int sqlite3_mallocDisallowed; /* assert() in sqlite3Malloc() if set */
  extern int sqlite3_isFail;           /* True if all malloc calls should fail */
  extern const char *sqlite3_zFile;    /* Filename to associate debug info with */
  extern int sqlite3_iLine;            /* Line number for debug info */
  
  #define ENTER_MALLOC (sqlite3_zFile = __FILE__, sqlite3_iLine = __LINE__)
  #define sqliteMalloc(x)          (ENTER_MALLOC, sqlite3Malloc(x,1))
  #define sqliteMallocRaw(x)       (ENTER_MALLOC, sqlite3MallocRaw(x,1))
  #define sqliteRealloc(x,y)       (ENTER_MALLOC, sqlite3Realloc(x,y))
  #define sqliteStrDup(x)          (ENTER_MALLOC, sqlite3StrDup(x))
  #define sqliteStrNDup(x,y)       (ENTER_MALLOC, sqlite3StrNDup(x,y))
  #define sqliteReallocOrFree(x,y) (ENTER_MALLOC, sqlite3ReallocOrFree(x,y))
  
  #else
  
  #define ENTER_MALLOC 0
  #define sqliteMalloc(x)          sqlite3Malloc(x,1)
  #define sqliteMallocRaw(x)       sqlite3MallocRaw(x,1)
  #define sqliteRealloc(x,y)       sqlite3Realloc(x,y)
  #define sqliteStrDup(x)          sqlite3StrDup(x)
  #define sqliteStrNDup(x,y)       sqlite3StrNDup(x,y)
  #define sqliteReallocOrFree(x,y) sqlite3ReallocOrFree(x,y)
  
  #endif
  
  #define sqliteFree(x)          sqlite3FreeX(x)
  #define sqliteAllocSize(x)     sqlite3AllocSize(x)
  
  
  /*
  ** An instance of this structure might be allocated to store information
  ** specific to a single thread.
  */
  struct ThreadData {
    int dummy;               /* So that this structure is never empty */
  
  #ifdef SQLITE_ENABLE_MEMORY_MANAGEMENT
    int nSoftHeapLimit;      /* Suggested max mem allocation.  No limit if <0 */
    int nAlloc;              /* Number of bytes currently allocated */
    //Pager *pPager;           /* Linked list of all pagers in this thread */
  #endif
  
  #ifndef SQLITE_OMIT_SHARED_CACHE
    u8 useSharedData;        /* True if shared pagers and schemas are enabled */
    //BtShared *pBtree;        /* Linked list of all currently open BTrees */
  #endif
  };
  
  /*
  ** Name of the master database table.  The master database table
  ** is a special table that holds the names and attributes of all
  ** user tables and indices.
  */
  #define MASTER_NAME       "sqlite_master"
  #define TEMP_MASTER_NAME  "sqlite_temp_master"
  
  /*
  ** The root-page of the master database table.
  */
  #define MASTER_ROOT       1
  
  /*
  ** The name of the schema table.
  */
  #define SCHEMA_TABLE(x)  ((!OMIT_TEMPDB)&&(x==1)?TEMP_MASTER_NAME:MASTER_NAME)
  
  /*
  ** A convenience macro that returns the number of elements in
  ** an array.
  */
  #define ArraySize(X)    (sizeof(X)/sizeof(X[0]))
  
  /*
  ** Forward references to structures
  */
  typedef struct AggInfo AggInfo;
  typedef struct AuthContext AuthContext;
  typedef struct CollSeq CollSeq;
  typedef struct Column Column;
  typedef struct Db Db;
  typedef struct Schema Schema;
  typedef struct Expr Expr;
  typedef struct ExprList ExprList;
  typedef struct FKey FKey;
  typedef struct FuncDef FuncDef;
  typedef struct IdList IdList;
  typedef struct Index Index;
  typedef struct KeyClass KeyClass;
  typedef struct KeyInfo KeyInfo;
  typedef struct NameContext NameContext;
  typedef struct Parse Parse;
  typedef struct Select Select;
  typedef struct SrcList SrcList;
  typedef struct ThreadData ThreadData;
  typedef struct Table Table;
  typedef struct TableLock TableLock;
  typedef struct Token Token;
  typedef struct TriggerStack TriggerStack;
  typedef struct TriggerStep TriggerStep;
  typedef struct Trigger Trigger;
  typedef struct WhereInfo WhereInfo;
  typedef struct WhereLevel WhereLevel;
  
  /*
  ** Each database file to be accessed by the system is an instance
  ** of the following structure.  There are normally two of these structures
  ** in the sqlite.aDb[] array.  aDb[0] is the main database file and
  ** aDb[1] is the database file used to hold temporary tables.  Additional
  ** databases may be attached.
  */
  /* struct Db { */
  /*   char *zName;         /1* Name of this database *1/ */
  /*   Btree *pBt;          /1* The B*Tree structure for this database file *1/ */
  /*   u8 inTrans;          /1* 0: not writable.  1: Transaction.  2: Checkpoint *1/ */
  /*   u8 safety_level;     /1* How aggressive at synching data to disk *1/ */
  /*   void *pAux;               /1* Auxiliary data.  Usually NULL *1/ */
  /*   void (*xFreeAux)(void*);  /1* Routine to free pAux *1/ */
  /*   Schema *pSchema;     /1* Pointer to database schema (possibly shared) *1/ */
  /* }; */
  
  /*
  ** An instance of the following structure stores a database schema.
  */
  struct Schema {
    int schema_cookie;   /* Database schema version number for this file */
    Hash tblHash;        /* All tables indexed by name */
    Hash idxHash;        /* All (named) indices indexed by name */
    Hash trigHash;       /* All triggers indexed by name */
    Hash aFKey;          /* Foreign keys indexed by to-table */
    Table *pSeqTab;      /* The sqlite_sequence table used by AUTOINCREMENT */
    u8 file_format;      /* Schema format version for this file */
    u8 enc;              /* Text encoding used by this database */
    u16 flags;           /* Flags associated with this schema */
    int cache_size;      /* Number of pages to use in the cache */
  };
  
  /*
  ** These macros can be used to test, set, or clear bits in the 
  ** Db.flags field.
  */
  #define DbHasProperty(D,I,P)     (((D)->aDb[I].pSchema->flags&(P))==(P))
  #define DbHasAnyProperty(D,I,P)  (((D)->aDb[I].pSchema->flags&(P))!=0)
  #define DbSetProperty(D,I,P)     (D)->aDb[I].pSchema->flags|=(P)
  #define DbClearProperty(D,I,P)   (D)->aDb[I].pSchema->flags&=~(P)
  
  /*
  ** Allowed values for the DB.flags field.
  **
  ** The DB_SchemaLoaded flag is set after the database schema has been
  ** read into internal hash tables.
  **
  ** DB_UnresetViews means that one or more views have column names that
  ** have been filled out.  If the schema changes, these column names might
  ** changes and so the view will need to be reset.
  */
  #define DB_SchemaLoaded    0x0001  /* The schema has been loaded */
  #define DB_UnresetViews    0x0002  /* Some views have defined column names */
  #define DB_Empty           0x0004  /* The file is empty (length 0 bytes) */
  
  #define SQLITE_UTF16NATIVE (SQLITE_BIGENDIAN?SQLITE_UTF16BE:SQLITE_UTF16LE)
  
  /*
  ** Each database is an instance of the following structure.
  **
  ** The sqlite.lastRowid records the last insert rowid generated by an
  ** insert statement.  Inserts on views do not affect its value.  Each
  ** trigger has its own context, so that lastRowid can be updated inside
  ** triggers as usual.  The previous value will be restored once the trigger
  ** exits.  Upon entering a before or instead of trigger, lastRowid is no
  ** longer (since after version 2.8.12) reset to -1.
  **
  ** The sqlite.nChange does not count changes within triggers and keeps no
  ** context.  It is reset at start of sqlite3_exec.
  ** The sqlite.lsChange represents the number of changes made by the last
  ** insert, update, or delete statement.  It remains constant throughout the
  ** length of a statement and is then updated by OP_SetCounts.  It keeps a
  ** context stack just like lastRowid so that the count of changes
  ** within a trigger is not seen outside the trigger.  Changes to views do not
  ** affect the value of lsChange.
  ** The sqlite.csChange keeps track of the number of current changes (since
  ** the last statement) and is used to update sqlite_lsChange.
  **
  ** The member variables sqlite.errCode, sqlite.zErrMsg and sqlite.zErrMsg16
  ** store the most recent error code and, if applicable, string. The
  ** internal function sqlite3Error() is used to set these variables
  ** consistently.
  */
  struct sqlite3 {
    int nDb;                      /* Number of backends currently in use */
    //Db *aDb;                      /* All backends */
    int flags;                    /* Miscellanous flags. See below */
    int errCode;                  /* Most recent error code (SQLITE_*) */
    u8 autoCommit;                /* The auto-commit flag. */
    u8 temp_store;                /* 1: file 2: memory 0: default */
    int nTable;                   /* Number of tables in the database */
    CollSeq *pDfltColl;           /* The default collating sequence (BINARY) */
    i64 lastRowid;                /* ROWID of most recent insert (see above) */
    i64 priorNewRowid;            /* Last randomly generated ROWID */
    int magic;                    /* Magic number for detect library misuse */
    int nChange;                  /* Value returned by sqlite3_changes() */
    int nTotalChange;             /* Value returned by sqlite3_total_changes() */
    struct sqlite3InitInfo {      /* Information used during initialization */
      int iDb;                    /* When back is being initialized */
      int newTnum;                /* Rootpage of table being initialized */
      u8 busy;                    /* TRUE if currently initializing */
    } init;
    //struct Vdbe *pVdbe;           /* List of active virtual machines */
    int activeVdbeCnt;            /* Number of vdbes currently executing */
    void (*xTrace)(void*,const char*);        /* Trace function */
    void *pTraceArg;                          /* Argument to the trace function */
    void (*xProfile)(void*,const char*,u64);  /* Profiling function */
    void *pProfileArg;                        /* Argument to profile function */
    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);
    void(*xCollNeeded)(void*,sqlite3*,int eTextRep,const char*);
    void(*xCollNeeded16)(void*,sqlite3*,int eTextRep,const void*);
    void *pCollNeededArg;
    sqlite3_value *pErr;          /* Most recent error message */
    char *zErrMsg;                /* Most recent error message (UTF-8 encoded) */
    char *zErrMsg16;              /* Most recent error message (UTF-16 encoded) */
  #ifndef SQLITE_OMIT_AUTHORIZATION
    int (*xAuth)(void*,int,const char*,const char*,const char*,const char*);
                                  /* Access authorization function */
    void *pAuthArg;               /* 1st argument to the access auth function */
  #endif
  #ifndef SQLITE_OMIT_PROGRESS_CALLBACK
    int (*xProgress)(void *);     /* The progress callback */
    void *pProgressArg;           /* Argument to the progress callback */
    int nProgressOps;             /* Number of opcodes for progress callback */
  #endif
  #ifndef SQLITE_OMIT_GLOBALRECOVER
    sqlite3 *pNext;               /* Linked list of open db handles. */
  #endif
    Hash aFunc;                   /* All functions that can be in SQL exprs */
    Hash aCollSeq;                /* All collating sequences */
    BusyHandler busyHandler;      /* Busy callback */
    int busyTimeout;             /* Busy handler timeout, in msec */
   // Db aDbStatic[2];              /* Static space for the 2 default backends */
  #ifdef SQLITE_SSE
    //sqlite3_stmt *pFetch;         /* Used by SSE to fetch stored statements */
  #endif
  };
  
  /*
  ** A macro to discover the encoding of a database.
  */
  #define ENC(db) ((db)->aDb[0].pSchema->enc)
  
  /*
  ** Possible values for the sqlite.flags and or Db.flags fields.
  **
  ** On sqlite.flags, the SQLITE_InTrans value means that we have
  ** executed a BEGIN.  On Db.flags, SQLITE_InTrans means a statement
  ** transaction is active on that particular database file.
  */
  #define SQLITE_VdbeTrace      0x00000001  /* True to trace VDBE execution */
  #define SQLITE_Interrupt      0x00000004  /* Cancel current operation */
  #define SQLITE_InTrans        0x00000008  /* True if in a transaction */
  #define SQLITE_InternChanges  0x00000010  /* Uncommitted Hash table changes */
  #define SQLITE_FullColNames   0x00000020  /* Show full column names on SELECT */
  #define SQLITE_ShortColNames  0x00000040  /* Show short columns names */
  #define SQLITE_CountRows      0x00000080  /* Count rows changed by INSERT, */
                                            /*   DELETE, or UPDATE and return */
                                            /*   the count using a callback. */
  #define SQLITE_NullCallback   0x00000100  /* Invoke the callback once if the */
                                            /*   result set is empty */
  #define SQLITE_SqlTrace       0x00000200  /* Debug print SQL as it executes */
  #define SQLITE_VdbeListing    0x00000400  /* Debug listings of VDBE programs */
  #define SQLITE_WriteSchema    0x00000800  /* OK to update SQLITE_MASTER */
  #define SQLITE_NoReadlock     0x00001000  /* Readlocks are omitted when 
                                            ** accessing read-only databases */
  #define SQLITE_IgnoreChecks   0x00002000  /* Do not enforce check constraints */
  #define SQLITE_ReadUncommitted 0x00004000  /* For shared-cache mode */
  #define SQLITE_LegacyFileFmt  0x00008000  /* Create new databases in format 1 */
  #define SQLITE_FullFSync      0x00010000  /* Use full fsync on the backend */
  
  /*
  ** Possible values for the sqlite.magic field.
  ** The numbers are obtained at random and have no special meaning, other
  ** than being distinct from one another.
  */
  #define SQLITE_MAGIC_OPEN     0xa029a697  /* Database is open */
  #define SQLITE_MAGIC_CLOSED   0x9f3c2d33  /* Database is closed */
  #define SQLITE_MAGIC_BUSY     0xf03b7906  /* Database currently in use */
  #define SQLITE_MAGIC_ERROR    0xb5357930  /* An SQLITE_MISUSE error occurred */
  
  /*
  ** Each SQL function is defined by an instance of the following
  ** structure.  A pointer to this structure is stored in the sqlite.aFunc
  ** hash table.  When multiple functions have the same name, the hash table
  ** points to a linked list of these structures.
  */
  struct FuncDef {
    i16 nArg;            /* Number of arguments.  -1 means unlimited */
    u8 iPrefEnc;         /* Preferred text encoding (SQLITE_UTF8, 16LE, 16BE) */
    u8 needCollSeq;      /* True if sqlite3GetFuncCollSeq() might be called */
    u8 flags;            /* Some combination of SQLITE_FUNC_* */
    void *pUserData;     /* User data parameter */
    FuncDef *pNext;      /* Next function with same name */
    void (*xFunc)(sqlite3_context*,int,sqlite3_value**); /* Regular function */
    void (*xStep)(sqlite3_context*,int,sqlite3_value**); /* Aggregate step */
    void (*xFinalize)(sqlite3_context*);                /* Aggregate finializer */
    char zName[1];       /* SQL name of the function.  MUST BE LAST */
  };
  
  /*
  ** Possible values for FuncDef.flags
  */
  #define SQLITE_FUNC_LIKE   0x01  /* Candidate for the LIKE optimization */
  #define SQLITE_FUNC_CASE   0x02  /* Case-sensitive LIKE-type function */
  
  /*
  ** information about each column of an SQL table is held in an instance
  ** of this structure.
  */
  struct Column {
    char *zName;     /* Name of this column */
    Expr *pDflt;     /* Default value of this column */
    char *zType;     /* Data type for this column */
    char *zColl;     /* Collating sequence.  If NULL, use the default */
    u8 notNull;      /* True if there is a NOT NULL constraint */
    u8 isPrimKey;    /* True if this column is part of the PRIMARY KEY */
    char affinity;   /* One of the SQLITE_AFF_... values */
  };
  
  /*
  ** A "Collating Sequence" is defined by an instance of the following
  ** structure. Conceptually, a collating sequence consists of a name and
  ** a comparison routine that defines the order of that sequence.
  **
  ** There may two seperate implementations of the collation function, one
  ** that processes text in UTF-8 encoding (CollSeq.xCmp) and another that
  ** processes text encoded in UTF-16 (CollSeq.xCmp16), using the machine
  ** native byte order. When a collation sequence is invoked, SQLite selects
  ** the version that will require the least expensive encoding
  ** translations, if any.
  **
  ** The CollSeq.pUser member variable is an extra parameter that passed in
  ** as the first argument to the UTF-8 comparison function, xCmp.
  ** CollSeq.pUser16 is the equivalent for the UTF-16 comparison function,
  ** xCmp16.
  **
  ** If both CollSeq.xCmp and CollSeq.xCmp16 are NULL, it means that the
  ** collating sequence is undefined.  Indices built on an undefined
  ** collating sequence may not be read or written.
  */
  struct CollSeq {
    char *zName;         /* Name of the collating sequence, UTF-8 encoded */
    u8 enc;              /* Text encoding handled by xCmp() */
    u8 type;             /* One of the SQLITE_COLL_... values below */
    void *pUser;         /* First argument to xCmp() */
    int (*xCmp)(void*,int, const void*, int, const void*);
  };
  
  /*
  ** Allowed values of CollSeq flags:
  */
  #define SQLITE_COLL_BINARY  1  /* The default memcmp() collating sequence */
  #define SQLITE_COLL_NOCASE  2  /* The built-in NOCASE collating sequence */
  #define SQLITE_COLL_REVERSE 3  /* The built-in REVERSE collating sequence */
  #define SQLITE_COLL_USER    0  /* Any other user-defined collating sequence */
  
  /*
  ** A sort order can be either ASC or DESC.
  */
  #define SQLITE_SO_ASC       0  /* Sort in ascending order */
  #define SQLITE_SO_DESC      1  /* Sort in ascending order */
  
  /*
  ** Column affinity types.
  **
  ** These used to have mnemonic name like 'i' for SQLITE_AFF_INTEGER and
  ** 't' for SQLITE_AFF_TEXT.  But we can save a little space and improve
  ** the speed a little by number the values consecutively.  
  **
  ** But rather than start with 0 or 1, we begin with 'a'.  That way,
  ** when multiple affinity types are concatenated into a string and
  ** used as the P3 operand, they will be more readable.
  **
  ** Note also that the numeric types are grouped together so that testing
  ** for a numeric type is a single comparison.
  */
  #define SQLITE_AFF_TEXT     'a'
  #define SQLITE_AFF_NONE     'b'
  #define SQLITE_AFF_NUMERIC  'c'
  #define SQLITE_AFF_INTEGER  'd'
  #define SQLITE_AFF_REAL     'e'
  
  #define sqlite3IsNumericAffinity(X)  ((X)>=SQLITE_AFF_NUMERIC)
  
  /*
  ** Each SQL table is represented in memory by an instance of the
  ** following structure.
  **
  ** Table.zName is the name of the table.  The case of the original
  ** CREATE TABLE statement is stored, but case is not significant for
  ** comparisons.
  **
  ** Table.nCol is the number of columns in this table.  Table.aCol is a
  ** pointer to an array of Column structures, one for each column.
  **
  ** If the table has an INTEGER PRIMARY KEY, then Table.iPKey is the index of
  ** the column that is that key.   Otherwise Table.iPKey is negative.  Note
  ** that the datatype of the PRIMARY KEY must be INTEGER for this field to
  ** be set.  An INTEGER PRIMARY KEY is used as the rowid for each row of
  ** the table.  If a table has no INTEGER PRIMARY KEY, then a random rowid
  ** is generated for each row of the table.  Table.hasPrimKey is true if
  ** the table has any PRIMARY KEY, INTEGER or otherwise.
  **
  ** Table.tnum is the page number for the root BTree page of the table in the
  ** database file.  If Table.iDb is the index of the database table backend
  ** in sqlite.aDb[].  0 is for the main database and 1 is for the file that
  ** holds temporary tables and indices.  If Table.isTransient
  ** is true, then the table is stored in a file that is automatically deleted
  ** when the VDBE cursor to the table is closed.  In this case Table.tnum 
  ** refers VDBE cursor number that holds the table open, not to the root
  ** page number.  Transient tables are used to hold the results of a
  ** sub-query that appears instead of a real table name in the FROM clause 
  ** of a SELECT statement.
  */
  struct Table {
    char *zName;     /* Name of the table */
    int nCol;        /* Number of columns in this table */
    Column *aCol;    /* Information about each column */
    int iPKey;       /* If not less then 0, use aCol[iPKey] as the primary key */
    Index *pIndex;   /* List of SQL indexes on this table. */
    int tnum;        /* Root BTree node for this table (see note above) */
    Select *pSelect; /* NULL for tables.  Points to definition if a view. */
    u8 readOnly;     /* True if this table should not be written by the user */
    u8 isTransient;  /* True if automatically deleted when VDBE finishes */
    u8 hasPrimKey;   /* True if there exists a primary key */
    u8 keyConf;      /* What to do in case of uniqueness conflict on iPKey */
    u8 autoInc;      /* True if the integer primary key is autoincrement */
    int nRef;          /* Number of pointers to this Table */
    Trigger *pTrigger; /* List of SQL triggers on this table */
    FKey *pFKey;       /* Linked list of all foreign keys in this table */
    char *zColAff;     /* String defining the affinity of each column */
  #ifndef SQLITE_OMIT_CHECK
    Expr *pCheck;      /* The AND of all CHECK constraints */
  #endif
  #ifndef SQLITE_OMIT_ALTERTABLE
    int addColOffset;  /* Offset in CREATE TABLE statement to add a new column */
  #endif
    Schema *pSchema;
  };
  
  /*
  ** Each foreign key constraint is an instance of the following structure.
  **
  ** A foreign key is associated with two tables.  The "from" table is
  ** the table that contains the REFERENCES clause that creates the foreign
  ** key.  The "to" table is the table that is named in the REFERENCES clause.
  ** Consider this example:
  **
  **     CREATE TABLE ex1(
  **       a INTEGER PRIMARY KEY,
  **       b INTEGER CONSTRAINT fk1 REFERENCES ex2(x)
  **     );
  **
  ** For foreign key "fk1", the from-table is "ex1" and the to-table is "ex2".
  **
  ** Each REFERENCES clause generates an instance of the following structure
  ** which is attached to the from-table.  The to-table need not exist when
  ** the from-table is created.  The existance of the to-table is not checked
  ** until an attempt is made to insert data into the from-table.
  **
  ** The sqlite.aFKey hash table stores pointers to this structure
  ** given the name of a to-table.  For each to-table, all foreign keys
  ** associated with that table are on a linked list using the FKey.pNextTo
  ** field.
  */
  struct FKey {
    Table *pFrom;     /* The table that constains the REFERENCES clause */
    FKey *pNextFrom;  /* Next foreign key in pFrom */
    char *zTo;        /* Name of table that the key points to */
    FKey *pNextTo;    /* Next foreign key that points to zTo */
    int nCol;         /* Number of columns in this key */
    struct sColMap {  /* Mapping of columns in pFrom to columns in zTo */
      int iFrom;         /* Index of column in pFrom */
      char *zCol;        /* Name of column in zTo.  If 0 use PRIMARY KEY */
    } *aCol;          /* One entry for each of nCol column s */
    u8 isDeferred;    /* True if constraint checking is deferred till COMMIT */
    u8 updateConf;    /* How to resolve conflicts that occur on UPDATE */
    u8 deleteConf;    /* How to resolve conflicts that occur on DELETE */
    u8 insertConf;    /* How to resolve conflicts that occur on INSERT */
  };
  
  /*
  ** SQLite supports many different ways to resolve a contraint
  ** error.  ROLLBACK processing means that a constraint violation
  ** causes the operation in process to fail and for the current transaction
  ** to be rolled back.  ABORT processing means the operation in process
  ** fails and any prior changes from that one operation are backed out,
  ** but the transaction is not rolled back.  FAIL processing means that
  ** the operation in progress stops and returns an error code.  But prior
  ** changes due to the same operation are not backed out and no rollback
  ** occurs.  IGNORE means that the particular row that caused the constraint
  ** error is not inserted or updated.  Processing continues and no error
  ** is returned.  REPLACE means that preexisting database rows that caused
  ** a UNIQUE constraint violation are removed so that the new insert or
  ** update can proceed.  Processing continues and no error is reported.
  **
  ** RESTRICT, SETNULL, and CASCADE actions apply only to foreign keys.
  ** RESTRICT is the same as ABORT for IMMEDIATE foreign keys and the
  ** same as ROLLBACK for DEFERRED keys.  SETNULL means that the foreign
  ** key is set to NULL.  CASCADE means that a DELETE or UPDATE of the
  ** referenced table row is propagated into the row that holds the
  ** foreign key.
  ** 
  ** The following symbolic values are used to record which type
  ** of action to take.
  */
  #define OE_None     0   /* There is no constraint to check */
  #define OE_Rollback 1   /* Fail the operation and rollback the transaction */
  #define OE_Abort    2   /* Back out changes but do no rollback transaction */
  #define OE_Fail     3   /* Stop the operation but leave all prior changes */
  #define OE_Ignore   4   /* Ignore the error. Do not do the INSERT or UPDATE */
  #define OE_Replace  5   /* Delete existing record, then do INSERT or UPDATE */
  
  #define OE_Restrict 6   /* OE_Abort for IMMEDIATE, OE_Rollback for DEFERRED */
  #define OE_SetNull  7   /* Set the foreign key value to NULL */
  #define OE_SetDflt  8   /* Set the foreign key value to its default */
  #define OE_Cascade  9   /* Cascade the changes */
  
  #define OE_Default  99  /* Do whatever the default action is */
  
  
  /*
  ** An instance of the following structure is passed as the first
  ** argument to sqlite3VdbeKeyCompare and is used to control the 
  ** comparison of the two index keys.
  **
  ** If the KeyInfo.incrKey value is true and the comparison would
  ** otherwise be equal, then return a result as if the second key
  ** were larger.
  */
  struct KeyInfo {
    u8 enc;             /* Text encoding - one of the TEXT_Utf* values */
    u8 incrKey;         /* Increase 2nd key by epsilon before comparison */
    int nField;         /* Number of entries in aColl[] */
    u8 *aSortOrder;     /* If defined an aSortOrder[i] is true, sort DESC */
    CollSeq *aColl[1];  /* Collating sequence for each term of the key */
  };
  
  /*
  ** Each SQL index is represented in memory by an
  ** instance of the following structure.
  **
  ** The columns of the table that are to be indexed are described
  ** by the aiColumn[] field of this structure.  For example, suppose
  ** we have the following table and index:
  **
  **     CREATE TABLE Ex1(c1 int, c2 int, c3 text);
  **     CREATE INDEX Ex2 ON Ex1(c3,c1);
  **
  ** In the Table structure describing Ex1, nCol==3 because there are
  ** three columns in the table.  In the Index structure describing
  ** Ex2, nColumn==2 since 2 of the 3 columns of Ex1 are indexed.
  ** The value of aiColumn is {2, 0}.  aiColumn[0]==2 because the 
  ** first column to be indexed (c3) has an index of 2 in Ex1.aCol[].
  ** The second column to be indexed (c1) has an index of 0 in
  ** Ex1.aCol[], hence Ex2.aiColumn[1]==0.
  **
  ** The Index.onError field determines whether or not the indexed columns
  ** must be unique and what to do if they are not.  When Index.onError=OE_None,
  ** it means this is not a unique index.  Otherwise it is a unique index
  ** and the value of Index.onError indicate the which conflict resolution 
  ** algorithm to employ whenever an attempt is made to insert a non-unique
  ** element.
  */
  struct Index {
    char *zName;     /* Name of this index */
    int nColumn;     /* Number of columns in the table used by this index */
    int *aiColumn;   /* Which columns are used by this index.  1st is 0 */
    unsigned *aiRowEst; /* Result of ANALYZE: Est. rows selected by each column */
    Table *pTable;   /* The SQL table being indexed */
    int tnum;        /* Page containing root of this index in database file */
    u8 onError;      /* OE_Abort, OE_Ignore, OE_Replace, or OE_None */
    u8 autoIndex;    /* True if is automatically created (ex: by UNIQUE) */
    char *zColAff;   /* String defining the affinity of each column */
    Index *pNext;    /* The next index associated with the same table */
    Schema *pSchema; /* Schema containing this index */
    u8 *aSortOrder;  /* Array of size Index.nColumn. True==DESC, False==ASC */
    char **azColl;   /* Array of collation sequence names for index */
  };
  
  /*
  ** Each token coming out of the lexer is an instance of
  ** this structure.  Tokens are also used as part of an expression.
  **
  ** Note if Token.z==0 then Token.dyn and Token.n are undefined and
  ** may contain random values.  Do not make any assuptions about Token.dyn
  ** and Token.n when Token.z==0.
  */
  struct Token {
    const unsigned char *z; /* Text of the token.  Not NULL-terminated! */
    unsigned dyn  : 1;      /* True for malloced memory, false for static */
    unsigned n    : 31;     /* Number of characters in this token */
  };
  
  /*
  ** An instance of this structure contains information needed to generate
  ** code for a SELECT that contains aggregate functions.
  **
  ** If Expr.op==TK_AGG_COLUMN or TK_AGG_FUNCTION then Expr.pAggInfo is a
  ** pointer to this structure.  The Expr.iColumn field is the index in
  ** AggInfo.aCol[] or AggInfo.aFunc[] of information needed to generate
  ** code for that node.
  **
  ** AggInfo.pGroupBy and AggInfo.aFunc.pExpr point to fields within the
  ** original Select structure that describes the SELECT statement.  These
  ** fields do not need to be freed when deallocating the AggInfo structure.
  */
  struct AggInfo {
    u8 directMode;          /* Direct rendering mode means take data directly
                            ** from source tables rather than from accumulators */
    u8 useSortingIdx;       /* In direct mode, reference the sorting index rather
                            ** than the source table */
    int sortingIdx;         /* Cursor number of the sorting index */
    ExprList *pGroupBy;     /* The group by clause */
    int nSortingColumn;     /* Number of columns in the sorting index */
    struct AggInfo_col {    /* For each column used in source tables */
      int iTable;              /* Cursor number of the source table */
      int iColumn;             /* Column number within the source table */
      int iSorterColumn;       /* Column number in the sorting index */
      int iMem;                /* Memory location that acts as accumulator */
      Expr *pExpr;             /* The original expression */
    } *aCol;
    int nColumn;            /* Number of used entries in aCol[] */
    int nColumnAlloc;       /* Number of slots allocated for aCol[] */
    int nAccumulator;       /* Number of columns that show through to the output.
                            ** Additional columns are used only as parameters to
                            ** aggregate functions */
    struct AggInfo_func {   /* For each aggregate function */
      Expr *pExpr;             /* Expression encoding the function */
      FuncDef *pFunc;          /* The aggregate function implementation */
      int iMem;                /* Memory location that acts as accumulator */
      int iDistinct;           /* Virtual table used to enforce DISTINCT */
    } *aFunc;
    int nFunc;              /* Number of entries in aFunc[] */
    int nFuncAlloc;         /* Number of slots allocated for aFunc[] */
  };
  
  /*
  ** Each node of an expression in the parse tree is an instance
  ** of this structure.
  **
  ** Expr.op is the opcode.  The integer parser token codes are reused
  ** as opcodes here.  For example, the parser defines TK_GE to be an integer
  ** code representing the ">=" operator.  This same integer code is reused
  ** to represent the greater-than-or-equal-to operator in the expression
  ** tree.
  **
  ** Expr.pRight and Expr.pLeft are subexpressions.  Expr.pList is a list
  ** of argument if the expression is a function.
  **
  ** Expr.token is the operator token for this node.  For some expressions
  ** that have subexpressions, Expr.token can be the complete text that gave
  ** rise to the Expr.  In the latter case, the token is marked as being
  ** a compound token.
  **
  ** An expression of the form ID or ID.ID refers to a column in a table.
  ** For such expressions, Expr.op is set to TK_COLUMN and Expr.iTable is
  ** the integer cursor number of a VDBE cursor pointing to that table and
  ** Expr.iColumn is the column number for the specific column.  If the
  ** expression is used as a result in an aggregate SELECT, then the
  ** value is also stored in the Expr.iAgg column in the aggregate so that
  ** it can be accessed after all aggregates are computed.
  **
  ** If the expression is a function, the Expr.iTable is an integer code
  ** representing which function.  If the expression is an unbound variable
  ** marker (a question mark character '?' in the original SQL) then the
  ** Expr.iTable holds the index number for that variable.
  **
  ** If the expression is a subquery then Expr.iColumn holds an integer
  ** register number containing the result of the subquery.  If the
  ** subquery gives a constant result, then iTable is -1.  If the subquery
  ** gives a different answer at different times during statement processing
  ** then iTable is the address of a subroutine that computes the subquery.
  **
  ** The Expr.pSelect field points to a SELECT statement.  The SELECT might
  ** be the right operand of an IN operator.  Or, if a scalar SELECT appears
  ** in an expression the opcode is TK_SELECT and Expr.pSelect is the only
  ** operand.
  **
  ** If the Expr is of type OP_Column, and the table it is selecting from
  ** is a disk table or the "old.*" pseudo-table, then pTab points to the
  ** corresponding table definition.
  */
  struct Expr {
    u8 op;                 /* Operation performed by this node */
    char affinity;         /* The affinity of the column or 0 if not a column */
    u8 flags;              /* Various flags.  See below */
    CollSeq *pColl;        /* The collation type of the column or 0 */
    Expr *pLeft, *pRight, *pParent;  /* Left and right subnodes */
    ExprList *pList;       /* A list of expressions used as function arguments
                           ** or in "<expr> IN (<expr-list)" */
    Token token;           /* An operand token */
    Token span;            /* Complete text of the expression */
    int iTable, iColumn;   /* When op==TK_COLUMN, then this expr node means the
                           ** iColumn-th field of the iTable-th table. */
    AggInfo *pAggInfo;     /* Used by TK_AGG_COLUMN and TK_AGG_FUNCTION */
    int iAgg;              /* Which entry in pAggInfo->aCol[] or ->aFunc[] */
    int iRightJoinTable;   /* If EP_FromJoin, the right table of the join */
    Select *pSelect;       /* When the expression is a sub-select.  Also the
                           ** right side of "<expr> IN (<select>)" */
    Table *pTab;           /* Table for OP_Column expressions. */
    Schema *pSchema;
  };
  
  /*
  ** The following are the meanings of bits in the Expr.flags field.
  */
  #define EP_FromJoin     0x01  /* Originated in ON or USING clause of a join */
  #define EP_Agg          0x02  /* Contains one or more aggregate functions */
  #define EP_Resolved     0x04  /* IDs have been resolved to COLUMNs */
  #define EP_Error        0x08  /* Expression contains one or more errors */
  #define EP_Distinct     0x10  /* Aggregate function with DISTINCT keyword */
  #define EP_VarSelect    0x20  /* pSelect is correlated, not constant */
  #define EP_Dequoted     0x40  /* True if the string has been dequoted */
  
  /*
  ** These macros can be used to test, set, or clear bits in the 
  ** Expr.flags field.
  */
  #define ExprHasProperty(E,P)     (((E)->flags&(P))==(P))
  #define ExprHasAnyProperty(E,P)  (((E)->flags&(P))!=0)
  #define ExprSetProperty(E,P)     (E)->flags|=(P)
  #define ExprClearProperty(E,P)   (E)->flags&=~(P)
  
  /*
  ** A list of expressions.  Each expression may optionally have a
  ** name.  An expr/name combination can be used in several ways, such
  ** as the list of "expr AS ID" fields following a "SELECT" or in the
  ** list of "ID = expr" items in an UPDATE.  A list of expressions can
  ** also be used as the argument to a function, in which case the a.zName
  ** field is not used.
  */
  struct ExprList {
    int nExpr;             /* Number of expressions on the list */
    int nAlloc;            /* Number of entries allocated below */
    int iECursor;          /* VDBE Cursor associated with this ExprList */
    struct ExprList_item {
      Expr *pExpr;           /* The list of expressions */
      char *zName;           /* Token associated with this expression */
      u8 sortOrder;          /* 1 for DESC or 0 for ASC */
      u8 isAgg;              /* True if this is an aggregate like count(*) */
      u8 done;               /* A flag to indicate when processing is finished */
    } *a;                  /* One entry for each expression */
  };
  
  typedef struct ValuesList {
      int nValues;    /* Number of Values to insert*/
      int nAlloc;
      ExprList** a;    /* array of Values*/
  }ValuesList;
  
  /*
  ** An instance of this structure can hold a simple list of identifiers,
  ** such as the list "a,b,c" in the following statements:
  **
  **      INSERT INTO t(a,b,c) VALUES ...;
  **      CREATE INDEX idx ON t(a,b,c);
  **      CREATE TRIGGER trig BEFORE UPDATE ON t(a,b,c) ...;
  **
  ** The IdList.a.idx field is used when the IdList represents the list of
  ** column names after a table name in an INSERT statement.  In the statement
  **
  **     INSERT INTO t(a,b,c) ...
  **
  ** If "a" is the k-th column of table "t", then IdList.a[0].idx==k.
  */
  struct IdList {
    struct IdList_item {
      char *zName;      /* Name of the identifier */
      int idx;          /* Index in some Table.aCol[] of a column named zName */
    } *a;
    int nId;         /* Number of identifiers on the list */
    int nAlloc;      /* Number of entries allocated for a[] below */
  };
  
  /*
  ** The bitmask datatype defined below is used for various optimizations.
  */
  typedef unsigned int Bitmask;
  
  /*
  ** The following structure describes the FROM clause of a SELECT statement.
  ** Each table or subquery in the FROM clause is a separate element of
  ** the SrcList.a[] array.
  **
  ** With the addition of multiple database support, the following structure
  ** can also be used to describe a particular table such as the table that
  ** is modified by an INSERT, DELETE, or UPDATE statement.  In standard SQL,
  ** such a table must be a simple name: ID.  But in SQLite, the table can
  ** now be identified by a database name, a dot, then the table name: ID.ID.
  */
  struct SrcList {
    i16 nSrc;        /* Number of tables or subqueries in the FROM clause */
    i16 nAlloc;      /* Number of entries allocated in a[] below */
    struct SrcList_item {
      char *zDatabase;  /* Name of database holding this table */
      char *zName;      /* Name of the table */
      char *zAlias;     /* The "B" part of a "A AS B" phrase.  zName is the "A" */
      Table *pTab;      /* An SQL table corresponding to zName */
      Select *pSelect;  /* A SELECT statement used in place of a table name */
      u8 isPopulated;   /* Temporary table associated with SELECT is populated */
      u8 jointype;      /* Type of join between this table and the next */
      i16 iCursor;      /* The VDBE cursor number used to access this table */
      Expr *pOn;        /* The ON clause of a join */
      IdList *pUsing;   /* The USING clause of a join */
      Bitmask colUsed;  /* Bit N (1<<N) set if column N or pTab is used */
  
      Token tableToken;
      Token dbToken;
    } a[1];             /* One entry for each identifier on the list */
  };
  
  /*
  ** Permitted values of the SrcList.a.jointype field
  */
  #define JT_INNER     0x0001    /* Any kind of inner or cross join */
  #define JT_CROSS     0x0002    /* Explicit use of the CROSS keyword */
  #define JT_NATURAL   0x0004    /* True for a "natural" join */
  #define JT_LEFT      0x0008    /* Left outer join */
  #define JT_RIGHT     0x0010    /* Right outer join */
  #define JT_OUTER     0x0020    /* The "OUTER" keyword is present */
  #define JT_ERROR     0x0040    /* unknown or unsupported join type */
  #define JT_FULL      0x0080    /* FULL JOIN, add by wink*/
  /*
  ** For each nested loop in a WHERE clause implementation, the WhereInfo
  ** structure contains a single instance of this structure.  This structure
  ** is intended to be private the the where.c module and should not be
  ** access or modified by other modules.
  */
  struct WhereLevel {
    int iFrom;            /* Which entry in the FROM clause */
    int flags;            /* Flags associated with this level */
    int iMem;             /* First memory cell used by this level */
    int iLeftJoin;        /* Memory cell used to implement LEFT OUTER JOIN */
    Index *pIdx;          /* Index used.  NULL if no index */
    int iTabCur;          /* The VDBE cursor used to access the table */
    int iIdxCur;          /* The VDBE cursor used to acesss pIdx */
    int brk;              /* Jump here to break out of the loop */
    int cont;             /* Jump here to continue with the next loop cycle */
    int top;              /* First instruction of interior of the loop */
    int op, p1, p2;       /* Opcode used to terminate the loop */
    int nEq;              /* Number of == or IN constraints on this loop */
    int nIn;              /* Number of IN operators constraining this loop */
    int *aInLoop;         /* Loop terminators for IN operators */
  };
  
  /*
  ** The WHERE clause processing routine has two halves.  The
  ** first part does the start of the WHERE loop and the second
  ** half does the tail of the WHERE loop.  An instance of
  ** this structure is returned by the first half and passed
  ** into the second half to give some continuity.
  */
  struct WhereInfo {
    Parse *pParse;
    SrcList *pTabList;   /* List of tables in the join */
    int iTop;            /* The very beginning of the WHERE loop */
    int iContinue;       /* Jump here to continue with next record */
    int iBreak;          /* Jump here to break out of the loop */
    int nLevel;          /* Number of nested loop */
    WhereLevel a[1];     /* Information about each nest loop in the WHERE */
  };
  
  /*
  ** A NameContext defines a context in which to resolve table and column
  ** names.  The context consists of a list of tables (the pSrcList) field and
  ** a list of named expression (pEList).  The named expression list may
  ** be NULL.  The pSrc corresponds to the FROM clause of a SELECT or
  ** to the table being operated on by INSERT, UPDATE, or DELETE.  The
  ** pEList corresponds to the result set of a SELECT and is NULL for
  ** other statements.
  **
  ** NameContexts can be nested.  When resolving names, the inner-most 
  ** context is searched first.  If no match is found, the next outer
  ** context is checked.  If there is still no match, the next context
  ** is checked.  This process continues until either a match is found
  ** or all contexts are check.  When a match is found, the nRef member of
  ** the context containing the match is incremented. 
  **
  ** Each subquery gets a new NameContext.  The pNext field points to the
  ** NameContext in the parent query.  Thus the process of scanning the
  ** NameContext list corresponds to searching through successively outer
  ** subqueries looking for a match.
  */
  struct NameContext {
    Parse *pParse;       /* The parser */
    SrcList *pSrcList;   /* One or more tables used to resolve names */
    ExprList *pEList;    /* Optional list of named expressions */
    int nRef;            /* Number of names resolved by this context */
    int nErr;            /* Number of errors encountered while resolving names */
    u8 allowAgg;         /* Aggregate functions allowed here */
    u8 hasAgg;           /* True if aggregates are seen */
    u8 isCheck;          /* True if resolving names in a CHECK constraint */
    int nDepth;          /* Depth of subquery recursion. 1 for no recursion */
    AggInfo *pAggInfo;   /* Information about aggregates at this level */
    NameContext *pNext;  /* Next outer name context.  NULL for outermost */
  };
  
  /*
  ** An instance of the following structure contains all information
  ** needed to generate code for a single SELECT statement.
  **
  ** nLimit is set to -1 if there is no LIMIT clause.  nOffset is set to 0.
  ** If there is a LIMIT clause, the parser sets nLimit to the value of the
  ** limit and nOffset to the value of the offset (or 0 if there is not
  ** offset).  But later on, nLimit and nOffset become the memory locations
  ** in the VDBE that record the limit and offset counters.
  **
  ** addrOpenVirt[] entries contain the address of OP_OpenVirtual opcodes.
  ** These addresses must be stored so that we can go back and fill in
  ** the P3_KEYINFO and P2 parameters later.  Neither the KeyInfo nor
  ** the number of columns in P2 can be computed at the same time
  ** as the OP_OpenVirtual instruction is coded because not
  ** enough information about the compound query is known at that point.
  ** The KeyInfo for addrOpenVirt[0] and [1] contains collating sequences
  ** for the result set.  The KeyInfo for addrOpenVirt[2] contains collating
  ** sequences for the ORDER BY clause.
  */
  struct Select {
    ExprList *pEList;      /* The fields of the result */
    u8 op;                 /* One of: TK_UNION TK_ALL TK_INTERSECT TK_EXCEPT */
    u8 isDistinct;         /* True if the DISTINCT keyword is present */
    u8 isResolved;         /* True once sqlite3SelectResolve() has run. */
    u8 isAgg;              /* True if this is an aggregate query */
    u8 usesVirt;           /* True if uses an OpenVirtual opcode */
    u8 disallowOrderBy;    /* Do not allow an ORDER BY to be attached if TRUE */
    SrcList *pSrc;         /* The FROM clause */
    Expr *pWhere;          /* The WHERE clause */
    ExprList *pGroupBy;    /* The GROUP BY clause */
    Expr *pHaving;         /* The HAVING clause */
    ExprList *pOrderBy;    /* The ORDER BY clause */
    Select *pPrior;        /* Prior select in a compound select statement */
    Select *pRightmost;    /* Right-most select in a compound select statement */
    Expr *pLimit;          /* LIMIT expression. NULL means not used. */
    Expr *pOffset;         /* OFFSET expression. NULL means not used. */
    int iLimit, iOffset;   /* Memory registers holding LIMIT & OFFSET counters */
    int addrOpenVirt[3];   /* OP_OpenVirtual opcodes related to this select */
  };
  
  typedef struct Insert {
      SrcList *pTabList;    /* Name of table into which we are inserting */
      ExprList *pSetList;      /* List of values to be inserted */
      ValuesList *pValuesList;
      Select *pSelect;      /* A SELECT statement to use as the data source */
      IdList *pColumn;      /* Column names corresponding to IDLIST. */
      int onError;           /* How to handle constraint errors */
  }Insert;
  
  typedef struct Delete {
      SrcList *pTabList;     /* The table from which we should delete things */
      Expr *pWhere;           /* The WHERE clause.  May be null */
      Expr *pLimit;
      Expr *pOffset;
  }Delete;
  
  typedef struct Update {
      SrcList *pTabList;     /* The table in which we should change things */
      ExprList *pChanges;    /* Things to be changed */
      Expr *pWhere;          /* The WHERE clause.  May be null */
      int onError;            /* How to handle constraint errors */
      Expr *pLimit;
      Expr *pOffset;
  }Update;
  
  typedef struct SetStatement {
      ExprList *pSetList;
      Token   value;    /* value of SET NAMES or SET CHARACTER SET*/
  }SetStatement;
  
  /*
  ** The results of a select can be distributed in several ways.
  */
  #define SRT_Union        1  /* Store result as keys in an index */
  #define SRT_Except       2  /* Remove result from a UNION index */
  #define SRT_Discard      3  /* Do not save the results anywhere */
  
  /* The ORDER BY clause is ignored for all of the above */
  #define IgnorableOrderby(X) (X<=SRT_Discard)
  
  #define SRT_Callback     4  /* Invoke a callback with each row of result */
  #define SRT_Mem          5  /* Store result in a memory cell */
  #define SRT_Set          6  /* Store non-null results as keys in an index */
  #define SRT_Table        7  /* Store result as data with an automatic rowid */
  #define SRT_VirtualTab   8  /* Create virtual table and store like SRT_Table */
  #define SRT_Subroutine   9  /* Call a subroutine to handle results */
  #define SRT_Exists      10  /* Store 1 if the result is not empty */
  
  typedef enum SqlType{
      SQLTYPE_UNKNOWN = 0,
      SQLTYPE_SELECT,
      SQLTYPE_UPDATE,
      SQLTYPE_INSERT,
      SQLTYPE_REPLACE,
      SQLTYPE_DELETE, 
      SQLTYPE_TRANSACTION_BEGIN,
      SQLTYPE_TRANSACTION_START,
      SQLTYPE_TRANSACTION_COMMIT,
      SQLTYPE_TRANSACTION_ROLLBACK,
      SQLTYPE_CREATE_TABLE,
      SQLTYPE_DROP_TABLE,
      SQLTYPE_SET,
      SQLTYPE_SET_NAMES,
      SQLTYPE_SET_CHARACTER_SET,
      SQLTYPE_SHOW,
  }SqlType;
  
  typedef enum ShowStatementType{
      SHOWTYPE_SHOW_DATABASES,
      SHOWTYPE_SHOW_TABLES,
      SHOWTYPE_SHOW_TABLE_STATUS,
      SHOWTYPE_SHOW_VARIABLES,
      SHOWTYPE_SHOW_COLLATION
  }ShowStatementType;
  
  typedef union ParsedResult {
      Select* selectObj;
      Insert* insertObj;
      Delete* deleteObj;
      Update* updateObj;
      SetStatement* setObj;
      ShowStatementType showType;
  } ParsedResult;
  
  typedef struct ParsedResultItem {
      ParsedResult result;
      SqlType sqltype;
  }ParsedResultItem;
  
  typedef struct ParsedResultArray {
      ParsedResultItem *array;
      u32     curSize;
      u32     allocSize;
  }ParsedResultArray;
  
  typedef struct TokenItem {
      Token token;
      int  tokenType;
  }TokenItem;
  
  typedef struct TokenArray {
      TokenItem *array;
      u32       curSize;
      u32       allocSize;
  }TokenArray;
  
  /*
  ** An SQL parser context.  A copy of this structure is passed through
  ** the parser and down into all the parser action routine in order to
  ** carry around information that is global to the entire parse.
  **
  ** The structure is divided into two parts.  When the parser and code
  ** generate call themselves recursively, the first part of the structure
  ** is constant but the second part is reset at the beginning and end of
  ** each recursion.
  **
  ** The nTableLock and aTableLock variables are only used if the shared-cache 
  ** feature is enabled (if sqlite3Tsd()->useSharedData is true). They are
  ** used to store the set of table-locks required by the statement being
  ** compiled. Function sqlite3TableLock() is used to add entries to the
  ** list.
  */
  struct Parse {
    //sqlite3 *db;         /* The main database structure */
    int flags;                    /* Miscellanous flags. See below */
    int rc;              /* Return code from execution */
    char *zErrMsg;       /* An error message */
    //Vdbe *pVdbe;         /* An engine for executing database bytecode */
    u8 colNamesSet;      /* TRUE after OP_ColumnName has been issued to pVdbe */
    u8 nameClash;        /* A permanent table name clashes with temp table name */
    u8 checkSchema;      /* Causes schema cookie check after an error */
    u8 nested;           /* Number of nested calls to the parser/code generator */
    int nErr;            /* Number of errors seen */
    int nTab;            /* Number of previously allocated VDBE cursors */
    int nMem;            /* Number of memory cells used so far */
    int nSet;            /* Number of sets used so far */
    int ckOffset;        /* Stack offset to data used by CHECK constraints */
    u32 writeMask;       /* Start a write transaction on these databases */
    u32 cookieMask;      /* Bitmask of schema verified databases */
    int cookieGoto;      /* Address of OP_Goto to cookie verifier subroutine */
    int cookieValue[MAX_ATTACHED+2];  /* Values of cookies to verify */
  #ifndef SQLITE_OMIT_SHARED_CACHE
    /* int nTableLock;        /1* Number of locks in aTableLock *1/ */
    /* TableLock *aTableLock; /1* Required table locks for shared-cache mode *1/ */
  #endif
  
    /* Above is constant between recursions.  Below is reset before and after
    ** each recursion */
  
    /* int nVar;            /1* Number of '?' variables seen in the SQL so far *1/ */
    /* int nVarExpr;        /1* Number of used slots in apVarExpr[] *1/ */
    /* int nVarExprAlloc;   /1* Number of allocated slots in apVarExpr[] *1/ */
    /* Expr **apVarExpr;    /1* Pointers to :aaa and $aaaa wildcard expressions *1/ */
    u8 explain;          /* True if the EXPLAIN flag is found on the query */
    Token sErrToken;     /* The token at which the error occurred */
    Token sNameToken;    /* Token with unqualified schema object name */
    Token sLastToken;    /* The last token parsed */
    const char *zSql;    /* All SQL text */
    const char *zTail;   /* All SQL text past the last semicolon parsed */
    /* Table *pNewTable;    /1* A table being constructed by CREATE TABLE *1/ */
    /* Trigger *pNewTrigger;     /1* Trigger under construct by a CREATE TRIGGER *1/ */
    /* TriggerStack *trigStack;  /1* Trigger actions being coded *1/ */
    /* const char *zAuthContext; /1* The 6th parameter to db->xAuth callbacks *1/ */
      
    ParsedResultArray parsed;
    TokenArray tokens;
  };
  
  /*
  ** An instance of the following structure can be declared on a stack and used
  ** to save the Parse.zAuthContext value so that it can be restored later.
  */
  struct AuthContext {
    const char *zAuthContext;   /* Put saved Parse.zAuthContext here */
    Parse *pParse;              /* The Parse structure */
  };
  
  /*
  ** Bitfield flags for P2 value in OP_Insert and OP_Delete
  */
  #define OPFLAG_NCHANGE   1    /* Set to update db->nChange */
  #define OPFLAG_LASTROWID 2    /* Set to update db->lastRowid */
  #define OPFLAG_ISUPDATE  4    /* This OP_Insert is an sql UPDATE */
  
  /*
   * Each trigger present in the database schema is stored as an instance of
   * struct Trigger. 
   *
   * Pointers to instances of struct Trigger are stored in two ways.
   * 1. In the "trigHash" hash table (part of the sqlite3* that represents the 
   *    database). This allows Trigger structures to be retrieved by name.
   * 2. All triggers associated with a single table form a linked list, using the
   *    pNext member of struct Trigger. A pointer to the first element of the
   *    linked list is stored as the "pTrigger" member of the associated
   *    struct Table.
   *
   * The "step_list" member points to the first element of a linked list
   * containing the SQL statements specified as the trigger program.
   */
  struct Trigger {
    char *name;             /* The name of the trigger                        */
    char *table;            /* The table or view to which the trigger applies */
    u8 op;                  /* One of TK_DELETE, TK_UPDATE, TK_INSERT         */
    u8 tr_tm;               /* One of TRIGGER_BEFORE, TRIGGER_AFTER */
    Expr *pWhen;            /* The WHEN clause of the expresion (may be NULL) */
    IdList *pColumns;       /* If this is an UPDATE OF <column-list> trigger,
                               the <column-list> is stored here */
    int foreach;            /* One of TK_ROW or TK_STATEMENT */
    Token nameToken;        /* Token containing zName. Use during parsing only */
    Schema *pSchema;        /* Schema containing the trigger */
    Schema *pTabSchema;     /* Schema containing the table */
    TriggerStep *step_list; /* Link list of trigger program steps             */
    Trigger *pNext;         /* Next trigger associated with the table */
  };
  
  /*
  ** A trigger is either a BEFORE or an AFTER trigger.  The following constants
  ** determine which. 
  **
  ** If there are multiple triggers, you might of some BEFORE and some AFTER.
  ** In that cases, the constants below can be ORed together.
  */
  #define TRIGGER_BEFORE  1
  #define TRIGGER_AFTER   2
  
  /*
   * An instance of struct TriggerStep is used to store a single SQL statement
   * that is a part of a trigger-program. 
   *
   * Instances of struct TriggerStep are stored in a singly linked list (linked
   * using the "pNext" member) referenced by the "step_list" member of the 
   * associated struct Trigger instance. The first element of the linked list is
   * the first step of the trigger-program.
   * 
   * The "op" member indicates whether this is a "DELETE", "INSERT", "UPDATE" or
   * "SELECT" statement. The meanings of the other members is determined by the 
   * value of "op" as follows:
   *
   * (op == TK_INSERT)
   * orconf    -> stores the ON CONFLICT algorithm
   * pSelect   -> If this is an INSERT INTO ... SELECT ... statement, then
   *              this stores a pointer to the SELECT statement. Otherwise NULL.
   * target    -> A token holding the name of the table to insert into.
   * pExprList -> If this is an INSERT INTO ... VALUES ... statement, then
   *              this stores values to be inserted. Otherwise NULL.
   * pIdList   -> If this is an INSERT INTO ... (<column-names>) VALUES ... 
   *              statement, then this stores the column-names to be
   *              inserted into.
   *
   * (op == TK_DELETE)
   * target    -> A token holding the name of the table to delete from.
   * pWhere    -> The WHERE clause of the DELETE statement if one is specified.
   *              Otherwise NULL.
   * 
   * (op == TK_UPDATE)
   * target    -> A token holding the name of the table to update rows of.
   * pWhere    -> The WHERE clause of the UPDATE statement if one is specified.
   *              Otherwise NULL.
   * pExprList -> A list of the columns to update and the expressions to update
   *              them to. See sqlite3Update() documentation of "pChanges"
   *              argument.
   * 
   */
  struct TriggerStep {
    int op;              /* One of TK_DELETE, TK_UPDATE, TK_INSERT, TK_SELECT */
    int orconf;          /* OE_Rollback etc. */
    Trigger *pTrig;      /* The trigger that this step is a part of */
  
    Select *pSelect;     /* Valid for SELECT and sometimes 
  			  INSERT steps (when pExprList == 0) */
    Token target;        /* Valid for DELETE, UPDATE, INSERT steps */
    Expr *pWhere;        /* Valid for DELETE, UPDATE steps */
    ExprList *pExprList; /* Valid for UPDATE statements and sometimes 
  			   INSERT steps (when pSelect == 0)         */
    IdList *pIdList;     /* Valid for INSERT statements only */
    TriggerStep *pNext;  /* Next in the link-list */
    TriggerStep *pLast;  /* Last element in link-list. Valid for 1st elem only */
  };
  
  /*
   * An instance of struct TriggerStack stores information required during code
   * generation of a single trigger program. While the trigger program is being
   * coded, its associated TriggerStack instance is pointed to by the
   * "pTriggerStack" member of the Parse structure.
   *
   * The pTab member points to the table that triggers are being coded on. The 
   * newIdx member contains the index of the vdbe cursor that points at the temp
   * table that stores the new.* references. If new.* references are not valid
   * for the trigger being coded (for example an ON DELETE trigger), then newIdx
   * is set to -1. The oldIdx member is analogous to newIdx, for old.* references.
   *
   * The ON CONFLICT policy to be used for the trigger program steps is stored 
   * as the orconf member. If this is OE_Default, then the ON CONFLICT clause 
   * specified for individual triggers steps is used.
   *
   * struct TriggerStack has a "pNext" member, to allow linked lists to be
   * constructed. When coding nested triggers (triggers fired by other triggers)
   * each nested trigger stores its parent trigger's TriggerStack as the "pNext" 
   * pointer. Once the nested trigger has been coded, the pNext value is restored
   * to the pTriggerStack member of the Parse stucture and coding of the parent
   * trigger continues.
   *
   * Before a nested trigger is coded, the linked list pointed to by the 
   * pTriggerStack is scanned to ensure that the trigger is not about to be coded
   * recursively. If this condition is detected, the nested trigger is not coded.
   */
  struct TriggerStack {
    Table *pTab;         /* Table that triggers are currently being coded on */
    int newIdx;          /* Index of vdbe cursor to "new" temp table */
    int oldIdx;          /* Index of vdbe cursor to "old" temp table */
    int orconf;          /* Current orconf policy */
    int ignoreJump;      /* where to jump to for a RAISE(IGNORE) */
    Trigger *pTrigger;   /* The trigger currently being coded */
    TriggerStack *pNext; /* Next trigger down on the trigger stack */
  };
  
  /*
  ** The following structure contains information used by the sqliteFix...
  ** routines as they walk the parse tree to make database references
  ** explicit.  
  */
  typedef struct DbFixer DbFixer;
  struct DbFixer {
    Parse *pParse;      /* The parsing context.  Error messages written here */
    const char *zDb;    /* Make sure all objects are contained in this database */
    const char *zType;  /* Type of the container - used for error messages */
    const Token *pName; /* Name of the container - used for error messages */
  };
  
  /*
  ** A pointer to this structure is used to communicate information
  ** from sqlite3Init and OP_ParseSchema into the sqlite3InitCallback.
  */
  typedef struct {
    sqlite3 *db;        /* The database being initialized */
    char **pzErrMsg;    /* Error message stored here */
  } InitData;
  
  /*
   * This global flag is set for performance testing of triggers. When it is set
   * SQLite will perform the overhead of building new and old trigger references 
   * even when no triggers exist
   */
  extern int sqlite3_always_code_trigger_setup;
  
  
  /*
  ** The SQLITE_CORRUPT_BKPT macro can be either a constant (for production
  ** builds) or a function call (for debugging).  If it is a function call,
  ** it allows the operator to set a breakpoint at the spot where database
  ** corruption is first detected.
  */
  #ifdef SQLITE_DEBUG
    extern int sqlite3Corrupt(void);
  # define SQLITE_CORRUPT_BKPT sqlite3Corrupt()
  #else
  # define SQLITE_CORRUPT_BKPT SQLITE_CORRUPT
  #endif
  
  /*
  ** Internal function prototypes
  */
  int sqlite3StrICmp(const char *, const char *);
  int sqlite3StrNICmp(const char *, const char *, int);
  int sqlite3HashNoCase(const char *, int);
  int sqlite3IsNumber(const char*, int*, u8);
  int sqlite3Compare(const char *, const char *);
  int sqlite3SortCompare(const char *, const char *);
  void sqlite3RealToSortable(double r, char *);
  
  void *sqlite3Malloc(int,int);
  void *sqlite3MallocRaw(int,int);
  void sqlite3Free(void*);
  void *sqlite3Realloc(void*,int);
  char *sqlite3StrDup(const char*);
  char *sqlite3StrNDup(const char*, int);
  # define sqlite3CheckMemory(a,b)
  void sqlite3ReallocOrFree(void**,int);
  void sqlite3FreeX(void*);
  void *sqlite3MallocX(int);
  int sqlite3AllocSize(void *);
  
  char *sqlite3MPrintf(const char*, ...);
  char *sqlite3VMPrintf(const char*, va_list);
  void sqlite3DebugPrintf(const char*, ...);
  void *sqlite3TextToPtr(const char*);
  void sqlite3SetString(char **, ...);
  void sqlite3ErrorMsg(Parse*, const char*, ...);
  void sqlite3ErrorClear(Parse*);
  void sqlite3Dequote(char*);
  void sqlite3DequoteExpr(Expr*);
  int sqlite3KeywordCode(const unsigned char*, int);
  int sqlite3RunParser(Parse*, const char*, char **);
  void sqlite3FinishCoding(Parse*);
  Expr *sqlite3Expr(int, Expr*, Expr*, const Token*);
  Expr *sqlite3RegisterExpr(Parse*,Token*);
  Expr *sqlite3ExprAnd(Expr*, Expr*);
  void sqlite3ExprSpan(Expr*,Token*,Token*);
  Expr *sqlite3ExprFunction(ExprList*, Token*);
  void sqlite3ExprAssignVarNumber(Parse*, Expr*);
  void sqlite3ExprDelete(Expr*);
  ExprList *sqlite3ExprListAppend(ExprList*,Expr*,Token*);
  void sqlite3ExprListDelete(ExprList*);
  int sqlite3Init(sqlite3*, char**);
  int sqlite3InitCallback(void*, int, char**, char**);
  void sqlite3Pragma(Parse*,Token*,Token*,Token*,int);
  void sqlite3ResetInternalSchema(sqlite3*, int);
  void sqlite3BeginParse(Parse*,int);
  void sqlite3RollbackInternalChanges(sqlite3*);
  void sqlite3CommitInternalChanges(sqlite3*);
  Table *sqlite3ResultSetOfSelect(Parse*,char*,Select*);
  void sqlite3OpenMasterTable(Parse *, int);
  void sqlite3StartTable(Parse*,Token*,Token*,int,int,int);
  void sqlite3AddColumn(Parse*,Token*);
  void sqlite3AddNotNull(Parse*, int);
  void sqlite3AddPrimaryKey(Parse*, ExprList*, int, int, int);
  void sqlite3AddCheckConstraint(Parse*, Expr*);
  void sqlite3AddColumnType(Parse*,Token*);
  void sqlite3AddDefaultValue(Parse*,Expr*);
  void sqlite3AddCollateType(Parse*, const char*, int);
  void sqlite3EndTable(Parse*,Token*,Token*,Select*);
  
  #ifndef SQLITE_OMIT_VIEW
    void sqlite3CreateView(Parse*,Token*,Token*,Token*,Select*,int);
    int sqlite3ViewGetColumnNames(Parse*,Table*);
  #else
  # define sqlite3ViewGetColumnNames(A,B) 0
  #endif
  
  void sqlite3DropTable(Parse*, SrcList*, int, int);
  void sqlite3DeleteTable(sqlite3*, Table*);
  //void sqlite3Insert(Parse*, SrcList*, ExprList*, Select*, IdList*, int);
  void sqlite3Insert(Parse*, SrcList*, ExprList*, ValuesList*, Select*, IdList*, int);
  int sqlite3ArrayAllocate(void**,int,int);
  IdList *sqlite3IdListAppend(IdList*, Token*);
  int sqlite3IdListIndex(IdList*,const char*);
  SrcList *sqlite3SrcListAppend(SrcList*, Token*, Token*);
  void sqlite3SrcListAddAlias(SrcList*, Token*);
  void sqlite3SrcListAssignCursors(Parse*, SrcList*);
  void sqlite3IdListDelete(IdList*);
  void sqlite3SrcListDelete(SrcList*);
  void sqlite3CreateIndex(Parse*,Token*,Token*,SrcList*,ExprList*,int,Token*,
                          Token*, int, int);
  void sqlite3DropIndex(Parse*, SrcList*, int);
  //void sqlite3AddKeyType(Vdbe*, ExprList*);
  //void sqlite3AddIdxKeyType(Vdbe*, Index*);
  int sqlite3Select(Parse*, Select*, int, int, Select*, int, int*, char *aff);
  Select *sqlite3SelectNew(ExprList*,SrcList*,Expr*,ExprList*,Expr*,ExprList*,
                          int,Expr*,Expr*);
  void sqlite3SelectDelete(Select*);
  void sqlite3SelectUnbind(Select*);
  Table *sqlite3SrcListLookup(Parse*, SrcList*);
  int sqlite3IsReadOnly(Parse*, Table*, int);
  void sqlite3OpenTable(Parse*, int iCur, int iDb, Table*, int);
  void sqlite3DeleteFrom(Parse*, SrcList*, Expr*, Expr*, Expr*);
  void sqlite3Update(Parse*, SrcList*, ExprList*, Expr*, int, Expr*, Expr*);
  WhereInfo *sqlite3WhereBegin(Parse*, SrcList*, Expr*, ExprList**);
  void sqlite3WhereEnd(WhereInfo*);
  void sqlite3ExprCode(Parse*, Expr*);
  void sqlite3ExprCodeAndCache(Parse*, Expr*);
  int sqlite3ExprCodeExprList(Parse*, ExprList*);
  void sqlite3ExprIfTrue(Parse*, Expr*, int, int);
  void sqlite3ExprIfFalse(Parse*, Expr*, int, int);
  void sqlite3NextedParse(Parse*, const char*, ...);
  Table *sqlite3FindTable(sqlite3*,const char*, const char*);
  Table *sqlite3LocateTable(Parse*,const char*, const char*);
  Index *sqlite3FindIndex(sqlite3*,const char*, const char*);
  void sqlite3UnlinkAndDeleteTable(sqlite3*,int,const char*);
  void sqlite3UnlinkAndDeleteIndex(sqlite3*,int,const char*);
  void sqlite3Vacuum(Parse*);
  int sqlite3RunVacuum(char**, sqlite3*);
  char *sqlite3NameFromToken(Token*);
  int sqlite3ExprCheck(Parse*, Expr*, int, int*);
  int sqlite3ExprCompare(Expr*, Expr*);
  int sqliteFuncId(Token*);
  int sqlite3ExprResolveNames(NameContext *, Expr *);
  int sqlite3ExprAnalyzeAggregates(NameContext*, Expr*);
  int sqlite3ExprAnalyzeAggList(NameContext*,ExprList*);
  //Vdbe *sqlite3GetVdbe(Parse*);
  void sqlite3Randomness(int, void*);
  void sqlite3RollbackAll(sqlite3*);
  void sqlite3CodeVerifySchema(Parse*, int);
  void sqlite3BeginTransaction(Parse*, int);
  void sqlite3CommitTransaction(Parse*);
  void sqlite3RollbackTransaction(Parse*);
  int sqlite3ExprIsConstant(Expr*);
  int sqlite3ExprIsConstantOrFunction(Expr*);
  int sqlite3ExprIsInteger(Expr*, int*);
  int sqlite3IsRowid(const char*);
  //void sqlite3GenerateRowDelete(sqlite3*, Vdbe*, Table*, int, int);
  //void sqlite3GenerateRowIndexDelete(Vdbe*, Table*, int, char*);
  //void sqlite3GenerateIndexKey(Vdbe*, Index*, int);
  void sqlite3GenerateConstraintChecks(Parse*,Table*,int,char*,int,int,int,int);
  void sqlite3CompleteInsertion(Parse*, Table*, int, char*, int, int, int);
  void sqlite3OpenTableAndIndices(Parse*, Table*, int, int);
  void sqlite3BeginWriteOperation(Parse*, int, int);
  Expr *sqlite3ExprDup(Expr*);
  void sqlite3TokenCopy(Token*, Token*);
  ExprList *sqlite3ExprListDup(ExprList*);
  SrcList *sqlite3SrcListDup(SrcList*);
  IdList *sqlite3IdListDup(IdList*);
  Select *sqlite3SelectDup(Select*);
  FuncDef *sqlite3FindFunction(sqlite3*,const char*,int,int,u8,int);
  void sqlite3RegisterBuiltinFunctions(sqlite3*);
  void sqlite3RegisterDateTimeFunctions(sqlite3*);
  int sqlite3SafetyOn(sqlite3*);
  int sqlite3SafetyOff(sqlite3*);
  int sqlite3SafetyCheck(sqlite3*);
  //void sqlite3ChangeCookie(sqlite3*, Vdbe*, int);
  
  #ifndef SQLITE_OMIT_TRIGGER
    void sqlite3BeginTrigger(Parse*, Token*,Token*,int,int,IdList*,SrcList*,
                             int,Expr*,int);
    void sqlite3FinishTrigger(Parse*, TriggerStep*, Token*);
    void sqlite3DropTrigger(Parse*, SrcList*);
    void sqlite3DropTriggerPtr(Parse*, Trigger*);
    int sqlite3TriggersExist(Parse*, Table*, int, ExprList*);
    int sqlite3CodeRowTrigger(Parse*, int, ExprList*, int, Table *, int, int, 
                             int, int);
    void sqliteViewTriggers(Parse*, Table*, Expr*, int, ExprList*);
    void sqlite3DeleteTriggerStep(TriggerStep*);
    TriggerStep *sqlite3TriggerSelectStep(Select*);
    TriggerStep *sqlite3TriggerInsertStep(Token*, IdList*, ExprList*,Select*,int);
    TriggerStep *sqlite3TriggerUpdateStep(Token*, ExprList*, Expr*, int);
    TriggerStep *sqlite3TriggerDeleteStep(Token*, Expr*);
    void sqlite3DeleteTrigger(Trigger*);
    void sqlite3UnlinkAndDeleteTrigger(sqlite3*,int,const char*);
  #else
  # define sqlite3TriggersExist(A,B,C,D,E,F) 0
  # define sqlite3DeleteTrigger(A)
  # define sqlite3DropTriggerPtr(A,B)
  # define sqlite3UnlinkAndDeleteTrigger(A,B,C)
  # define sqlite3CodeRowTrigger(A,B,C,D,E,F,G,H,I) 0
  #endif
  
  int sqlite3JoinType(Parse*, Token*, Token*, Token*);
  void sqlite3CreateForeignKey(Parse*, ExprList*, Token*, ExprList*, int);
  void sqlite3DeferForeignKey(Parse*, int);
  #ifndef SQLITE_OMIT_AUTHORIZATION
    void sqlite3AuthRead(Parse*,Expr*,SrcList*);
    int sqlite3AuthCheck(Parse*,int, const char*, const char*, const char*);
    void sqlite3AuthContextPush(Parse*, AuthContext*, const char*);
    void sqlite3AuthContextPop(AuthContext*);
  #else
  # define sqlite3AuthRead(a,b,c)
  # define sqlite3AuthCheck(a,b,c,d,e)    SQLITE_OK
  # define sqlite3AuthContextPush(a,b,c)
  # define sqlite3AuthContextPop(a)  ((void)(a))
  #endif
  void sqlite3Attach(Parse*, Expr*, Expr*, Expr*);
  void sqlite3Detach(Parse*, Expr*);
  //int sqlite3BtreeFactory(const sqlite3 *db, const char *zFilename,
  //                       int omitJournal, int nCache, Btree **ppBtree);
  int sqlite3FixInit(DbFixer*, Parse*, int, const char*, const Token*);
  int sqlite3FixSrcList(DbFixer*, SrcList*);
  int sqlite3FixSelect(DbFixer*, Select*);
  int sqlite3FixExpr(DbFixer*, Expr*);
  int sqlite3FixExprList(DbFixer*, ExprList*);
  int sqlite3FixTriggerStep(DbFixer*, TriggerStep*);
  int sqlite3AtoF(const char *z, double*);
  char *sqlite3_snprintf(int,char*,const char*,...);
  int sqlite3GetInt32(const char *, int*);
  int sqlite3FitsIn64Bits(const char *);
  int sqlite3utf16ByteLen(const void *pData, int nChar);
  int sqlite3utf8CharLen(const char *pData, int nByte);
  int sqlite3ReadUtf8(const unsigned char *);
  int sqlite3PutVarint(unsigned char *, u64);
  int sqlite3GetVarint(const unsigned char *, u64 *);
  int sqlite3GetVarint32(const unsigned char *, u32 *);
  int sqlite3VarintLen(u64 v);
  //void sqlite3IndexAffinityStr(Vdbe *, Index *);
  //void sqlite3TableAffinityStr(Vdbe *, Table *);
  char sqlite3CompareAffinity(Expr *pExpr, char aff2);
  int sqlite3IndexAffinityOk(Expr *pExpr, char idx_affinity);
  char sqlite3ExprAffinity(Expr *pExpr);
  int sqlite3atoi64(const char*, i64*);
  void sqlite3Error(sqlite3*, int, const char*,...);
  void *sqlite3HexToBlob(const char *z);
  int sqlite3TwoPartName(Parse *, Token *, Token *, Token **);
  const char *sqlite3ErrStr(int);
  int sqlite3ReadUniChar(const char *zStr, int *pOffset, u8 *pEnc, int fold);
  int sqlite3ReadSchema(Parse *pParse);
  CollSeq *sqlite3FindCollSeq(sqlite3*,u8 enc, const char *,int,int);
  CollSeq *sqlite3LocateCollSeq(Parse *pParse, const char *zName, int nName);
  CollSeq *sqlite3ExprCollSeq(Parse *pParse, Expr *pExpr);
  int sqlite3CheckCollSeq(Parse *, CollSeq *);
  int sqlite3CheckIndexCollSeq(Parse *, Index *);
  int sqlite3CheckObjectName(Parse *, const char *);
  void sqlite3VdbeSetChanges(sqlite3 *, int);
  void sqlite3utf16Substr(sqlite3_context *,int,sqlite3_value **);
  
  const void *sqlite3ValueText(sqlite3_value*, u8);
  int sqlite3ValueBytes(sqlite3_value*, u8);
  void sqlite3ValueSetStr(sqlite3_value*, int, const void *,u8, void(*)(void*));
  void sqlite3ValueFree(sqlite3_value*);
  sqlite3_value *sqlite3ValueNew(void);
  char *sqlite3utf16to8(const void*, int);
  int sqlite3ValueFromExpr(Expr *, u8, u8, sqlite3_value **);
  void sqlite3ValueApplyAffinity(sqlite3_value *, u8, u8);
  extern const unsigned char sqlite3UpperToLower[];
  void sqlite3RootPageMoved(Db*, int, int);
  void sqlite3Reindex(Parse*, Token*, Token*);
  void sqlite3AlterFunctions(sqlite3*);
  void sqlite3AlterRenameTable(Parse*, SrcList*, Token*);
  int sqlite3GetToken(const unsigned char *, int *);
  void sqlite3NestedParse(Parse*, const char*, ...);
  void sqlite3ExpirePreparedStatements(sqlite3*);
  void sqlite3CodeSubselect(Parse *, Expr *);
  int sqlite3SelectResolve(Parse *, Select *, NameContext *);
  //void sqlite3ColumnDefault(Vdbe *, Table *, int);
  void sqlite3AlterFinishAddColumn(Parse *, Token *);
  void sqlite3AlterBeginAddColumn(Parse *, SrcList *);
  const char *sqlite3TestErrorName(int);
  CollSeq *sqlite3GetCollSeq(sqlite3*, CollSeq *, const char *, int);
  char sqlite3AffinityType(const Token*);
  void sqlite3Analyze(Parse*, Token*, Token*);
  int sqlite3InvokeBusyHandler(BusyHandler*);
  int sqlite3FindDb(sqlite3*, Token*);
  void sqlite3AnalysisLoad(sqlite3*,int iDB);
  void sqlite3DefaultRowEst(Index*);
  void sqlite3RegisterLikeFunctions(sqlite3*, int);
  int sqlite3IsLikeFunction(sqlite3*,Expr*,int*,char*);
  ThreadData *sqlite3ThreadData(void);
  const ThreadData *sqlite3ThreadDataReadOnly(void);
  void sqlite3ReleaseThreadData(void);
  void sqlite3AttachFunctions(sqlite3 *);
  void sqlite3MinimumFileFormat(Parse*, int, int);
  void sqlite3SchemaFree(void *);
  //Schema *sqlite3SchemaGet(Btree *);
  int sqlite3SchemaToIndex(sqlite3 *db, Schema *);
  KeyInfo *sqlite3IndexKeyinfo(Parse *, Index *);
  int sqlite3CreateFunc(sqlite3 *, const char *, int, int, void *, 
    void (*)(sqlite3_context*,int,sqlite3_value **),
    void (*)(sqlite3_context*,int,sqlite3_value **), void (*)(sqlite3_context*));
  int sqlite3ApiExit(sqlite3 *db, int);
  int sqlite3MallocFailed(void);
  void sqlite3FailedMalloc(void);
  //void sqlite3AbortOtherActiveVdbes(sqlite3 *, Vdbe *);
  int sqlite3OpenTempDatabase(Parse *);
  
  Expr *sqlite3ExprLikeOp(ExprList *pList, Token *pToken);
  
  int sqlite3RunParser(Parse *pParse, const char *zSql, char **pzErrMsg);
  int sqlite3RunParser1(Parse *pParse, const char *zSql, int sqlLen, char **pzErrMsg);
  
  void resetParseObject(Parse *parseObj);
  
  Parse* sqlite3ParseNew();
  Parse* sqlite3ParseInit(Parse *parseObj);
  void sqlite3ParseReset(Parse *parseObj);
  void   sqlite3ParseDelete(Parse *parseObj);
  
  #define sqlite3ParseClean(X) sqlite3ParseReset(X)
  
  
  TokenArray* sqlite3TokenArrayAppend(TokenArray *tokenArray, TokenItem *item);
  ParsedResultArray* sqlite3ParsedResultArrayAppend(ParsedResultArray *resultArray, ParsedResultItem *result);
  void sqlite3ParsedResultArrayClean(ParsedResultArray *resultArray);
  
  Insert* sqlite3InsertNew(SrcList *pTabList, ExprList *pSetList, ValuesList *pValuesList, Select *pSelect, IdList *pColumn, int onError);
  void sqlite3InsertDelete(Insert *insertObj);
  
  Delete* sqlite3DeleteNew(SrcList *pTabList, Expr *pWhere, Expr *pLimit, Expr *pOffset);
  void sqlite3DeleteFree(Delete *deleteObj);
  
  Update* sqlite3UpdateNew(SrcList *pTabList, ExprList *pChanges, Expr *pWhere, int onError, Expr *pLimit, Expr *pOffset);
  void sqlite3UpdateDelete(Update* updateObj);
  
  SetStatement* sqlite3SetStatementNew(ExprList *pList, Token *pValue);
  void sqlite3SetStatementDelete(SetStatement* setObj);
  
  ValuesList *sqlite3ValuesListAppend(ValuesList *valueList, ExprList *exprList);
  void sqlite3ValuesListDelete(ValuesList *valuesList);
  
  void sqlite3SetStatement(Parse *pParse, ExprList *pExprList, Token *pToken, SqlType sqltype);
  void sqlite3CheckSetScope(Parse *pParse, Token *pScope);
  
  void sqlite3ShowStatement(Parse *pParse, ShowStatementType showtype);
  
  #ifndef SQLITE_OMIT_SHARED_CACHE
    void sqlite3TableLock(Parse *, int, int, u8, const char *);
  #else
    #define sqlite3TableLock(v,w,x,y,z)
  #endif
  
  #ifdef SQLITE_MEMDEBUG
    void sqlite3MallocDisallow(void);
    void sqlite3MallocAllow(void);
    int sqlite3TestMallocFail(void);
  #else
    #define sqlite3TestMallocFail() 0
    #define sqlite3MallocDisallow()
    #define sqlite3MallocAllow()
  #endif
  
  #ifdef SQLITE_ENABLE_MEMORY_MANAGEMENT
    void *sqlite3ThreadSafeMalloc(int);
    void sqlite3ThreadSafeFree(void *);
  #else
    #define sqlite3ThreadSafeMalloc sqlite3MallocX
    #define sqlite3ThreadSafeFree sqlite3FreeX
  #endif
  
  #ifdef SQLITE_SSE
  #include "sseInt.h"
  #endif
  
  #ifdef __cplusplus
  }
  #endif
  
  #endif
  