SQLite

** list of users and their access credentials.
*/
int sqlite3UserAuthTable(const char *zTable){
  return sqlite3_stricmp(zTable, "sqlite_user")==0;
}
#endif

#ifdef SQLITE_ENABLE_SHARED_SCHEMA
/*
** If this database connection was opened with the SQLITE_OPEN_SHARED_SCHEMA
** flag specified, then ensure that the database schema for database iDb
** is loaded. Either by obtaining a Schema object from the schema-pool, or
** by reading the contents of the sqlite_master table. Unless it is NULL, 
** the location indicated by parameter pbUnload is set to 1 if a shared-schema 
** is loaded.

    memset(&db->init, 0, sizeof(struct sqlite3InitInfo));
    rc = sqlite3InitOne(db, iDb, pzErr, 0);
    db->init = sv;
    if( pbUnload && rc==SQLITE_OK && iDb!=1 ) *pbUnload = 1;
  }
  return rc;
}
#endif

/*
** Locate the in-memory structure that describes a particular database
** table given the name of that table and (optionally) the name of the
** database containing the table.  Return NULL if not found.
**
** If zDatabase is 0, all databases are searched for the table and the

  int nDelete;                    /* Schema objects deleted by ReleaseAll() */
  u64 cksum;                      /* Checksum for this Schema contents */
  Schema *pSchema;                /* Linked list of Schema objects */
  Schema sSchema;                 /* The single dummy schema object */
  SchemaPool *pNext;              /* Next element in schemaPoolList */
};

#ifdef SQLITE_ENABLE_SHARED_SCHEMA
#ifdef SQLITE_DEBUG
static void assert_schema_state_ok(sqlite3 *db){
  if( IsSharedSchema(db) && db->magic!=SQLITE_MAGIC_ZOMBIE ){
    int i;
    for(i=0; i<db->nDb; i++){
      if( i!=1 ){
        Db *pDb = &db->aDb[i];

      }
    }
  }
}
#else
# define assert_schema_state_ok(x)
#endif
#endif /* ifdef SQLITE_ENABLE_SHARED_SCHEMA */

/*
** Invoke the 'collation needed' callback to request a collation sequence
** in the encoding enc of name zName, length nName.
*/
static void callCollNeeded(sqlite3 *db, int enc, const char *zName){
  assert( !db->xCollNeeded || !db->xCollNeeded16 );

** database iDb. 
**
** If an OOM error occurs while disconnecting from a schema-pool, 
** the db->mallocFailed flag is set.
*/
void sqlite3SchemaClearOrDisconnect(sqlite3 *db, int iDb){
  Db *pDb = &db->aDb[iDb];
#ifdef SQLITE_ENABLE_SHARED_SCHEMA
  if( IsSharedSchema(db) && iDb!=1 && pDb->pSPool ){
    sqlite3SchemaDisconnect(db, iDb, 1);
  }else
#endif
  {
    sqlite3SchemaClear(pDb->pSchema);
  }
}

#ifdef SQLITE_ENABLE_SHARED_SCHEMA
/*
** Global linked list of SchemaPool objects. Read and write access must
** be protected by the SQLITE_MUTEX_STATIC_MASTER mutex.
*/
static SchemaPool *SQLITE_WSD schemaPoolList = 0;

#ifdef SQLITE_TEST

  assert( iDb!=1 );
  assert_schema_state_ok(db);
  sqlite3_mutex_enter( sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_MASTER) );
  schemaRelease(db, pDb);
  sqlite3_mutex_leave( sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_MASTER) );
}

#endif /* ifdef SQLITE_ENABLE_SHARED_SCHEMA */

/*
** In most cases, this function finds and returns the schema associated 
** with BTree handle pBt, creating a new one if necessary. However, if
** the database handle was opened with the SQLITE_OPEN_SHARED_SCHEMA flag
** specified, a new, empty, Schema object in memory obtained by 
** sqlite3_malloc() is always returned.
*/
Schema *sqlite3SchemaGet(sqlite3 *db, Btree *pBt){
  Schema *p;
  if( pBt && IsSharedSchema(db)==0 ){
    p = (Schema*)sqlite3BtreeSchema(pBt, sizeof(Schema), sqlite3SchemaClear);
  }else{

    p = (Schema*)sqlite3DbMallocZero(0, sizeof(Schema));

  }
  if( !p ){
    sqlite3OomFault(db);
  }else if ( 0==p->file_format ){
    sqlite3HashInit(&p->tblHash);
    sqlite3HashInit(&p->idxHash);
    sqlite3HashInit(&p->trigHash);
    sqlite3HashInit(&p->fkeyHash);
    p->enc = SQLITE_UTF8;
  }
  return p;
}

    Schema *pSchema = db->aDb[i].pSchema;
    if( pSchema ){
      for(p=sqliteHashFirst(&pSchema->tblHash); p; p=sqliteHashNext(p)){
        Table *pTab = (Table *)sqliteHashData(p);
        if( IsVirtual(pTab) ) sqlite3VtabDisconnect(db, pTab);
      }
    }
#ifdef SQLITE_ENABLE_SHARED_SCHEMA
    if( IsSharedSchema(db) && i!=1 ){
      VTable *pVTable;
      VTable *pNext;
      for(pVTable=db->aDb[i].pVTable; pVTable; pVTable=pNext){
        pNext = pVTable->pNext;
        sqlite3VtabUnlock(pVTable);
      }
      db->aDb[i].pVTable = 0;
    }
#endif /* ifdef SQLITE_ENABLE_SHARED_SCHEMA */
  }
  for(p=sqliteHashFirst(&db->aModule); p; p=sqliteHashNext(p)){
    Module *pMod = (Module *)sqliteHashData(p);
    if( pMod->pEpoTab ){
      sqlite3VtabDisconnect(db, pMod->pEpoTab);
    }
  }

  sqlite3BtreeEnterAll(db);
  if( IsSharedSchema(db)==0 ){
    rc = sqlite3Init(db, &zErrMsg);
  }

  /* Locate the table in question */
  if( rc==SQLITE_OK ){
#ifdef SQLITE_ENABLE_SHARED_SCHEMA
    Parse sParse;                   /* Fake Parse object for FindTable */
    Parse *pSaved = db->pParse;
    memset(&sParse, 0, sizeof(sParse));
    db->pParse = &sParse;
#endif
    pTab = sqlite3FindTable(db, zTableName, zDbName);
#ifdef SQLITE_ENABLE_SHARED_SCHEMA
    sqlite3_free(sParse.zErrMsg);
    rc = sParse.rc;
    db->pParse = pSaved;
#endif
  }
  if( SQLITE_OK!=rc ) goto error_out;

  if( !pTab || pTab->pSelect ){
    pTab = 0;
    goto error_out;
  }

    z = sqlite3MPrintf(db, "malformed database schema (%s)", zObj);
    if( zExtra && zExtra[0] ) z = sqlite3MPrintf(db, "%z - %s", z, zExtra);
    *pData->pzErrMsg = z;
    pData->rc = SQLITE_CORRUPT_BKPT;
  }
}

#ifdef SQLITE_ENABLE_SHARED_SCHEMA
/*
** Update the Schema.cksum checksum to account for the database object
** specified by the three arguments following the first.
*/
static void schemaUpdateChecksum(
  InitData *pData,                /* Schema parse context */
  const char *zName,              /* Name of new database object */
  const char *zRoot,              /* Root page of new database object */
  const char *zSql                /* SQL used to create new database object */
){
  int i;
  u64 cksum = pData->cksum;
  if( zName ){
    for(i=0; zName[i]; i++) cksum += (cksum<<3) + zName[i];
  }
  if( zRoot ) for(i=0; zRoot[i]; i++) cksum += (cksum<<3) + zRoot[i];
  if( zSql ) for(i=0; zSql[i]; i++) cksum += (cksum<<3) + zSql[i];
  pData->cksum = cksum;
}
#endif /* ifdef SQLITE_ENABLE_SHARED_SCHEMA */

/*
** Check to see if any sibling index (another index on the same table)
** of pIndex has the same root page number, and if it does, return true.
** This would indicate a corrupt schema.
*/
int sqlite3IndexHasDuplicateRootPage(Index *pIndex){

      if( db->init.orphanTrigger ){
        assert( iDb==1 );
      }else{
        pData->rc = rc;
        if( rc==SQLITE_NOMEM ){
          sqlite3OomFault(db);
        }else if( rc!=SQLITE_INTERRUPT 
#ifdef SQLITE_ENABLE_SHARED_SCHEMA
               && (rc&0xFF)!=SQLITE_LOCKED 
               && (rc&0xFF)!=SQLITE_IOERR
#endif
        ){
          corruptSchema(pData, argv[0], sqlite3_errmsg(db));
        }
      }
    }
    sqlite3_finalize(pStmt);
  }else if( argv[0]==0 || (argv[2]!=0 && argv[2][0]!=0) ){

     || pIndex->tnum<2
     || sqlite3IndexHasDuplicateRootPage(pIndex)
    ){
      corruptSchema(pData, argv[0], pIndex?"invalid rootpage":"orphan index");
    }
  }

#ifdef SQLITE_ENABLE_SHARED_SCHEMA
  if( IsSharedSchema(db) && iDb!=1 ){
    schemaUpdateChecksum(pData, argv[0], argv[1], argv[2]);
  }
#endif
  return 0;
}

/*
** Attempt to read the database schema and initialize internal
** data structures for a single database file.  The index of the
** database file is given by iDb.  iDb==0 is used for the main

  assert( (db->mDbFlags & DBFLAG_SchemaKnownOk)==0 );
  assert( iDb>=0 && iDb<db->nDb );
  assert( db->aDb[iDb].pSchema || (IsSharedSchema(db) && iDb!=1) );
  assert( sqlite3_mutex_held(db->mutex) );
  assert( iDb==1 || sqlite3BtreeHoldsMutex(db->aDb[iDb].pBt) );

  pDb = &db->aDb[iDb];
#ifdef SQLITE_ENABLE_SHARED_SCHEMA
  assert( pDb->pSPool==0 || IsSharedSchema(db) );
  if( pDb->pSPool ){
    /* See if there is a free schema object in the schema-pool. If not,
    ** disconnect from said schema pool and continue. This function will
    ** connect to a (possibly different) schema-pool before returning. */
    Schema *pNew = sqlite3SchemaExtract(pDb->pSPool);
    if( pNew ){
      pDb->pSchema = pNew;
      return SQLITE_OK;
    }
    rc = sqlite3SchemaDisconnect(db, iDb, 1);
    if( rc!=SQLITE_OK ) goto error_out;
    assert( pDb->pSchema && pDb->pSPool==0 );
  }
#endif

  db->init.busy = 1;

  /* Construct the in-memory representation schema tables (sqlite_master or
  ** sqlite_temp_master) by invoking the parser directly.  The appropriate
  ** table name will be inserted automatically by the parser so we can just
  ** use the abbreviation "x" here.  The parser will also automatically tag

    }
    sqlite3ResetOneSchema(db, iDb);
  }
  db->init.busy = 0;
  return rc;
}


#ifdef SQLITE_ENABLE_SHARED_SCHEMA
/*
** If this is a SHARED_SCHEMA connection and the DBFLAG_SchemaInUse flag
** is not currently set, set it and return non-zero. Otherwise, return 0.
*/
int sqlite3LockReusableSchema(sqlite3 *db){
  if( IsSharedSchema(db) && (db->mDbFlags & DBFLAG_SchemaInuse)==0 ){
    db->mDbFlags |= DBFLAG_SchemaInuse;
    return 1;
  }
  return 0;
}
#endif /* ifdef SQLITE_ENABLE_SHARED_SCHEMA */

#ifdef SQLITE_ENABLE_SHARED_SCHEMA
/*
** This function is a no-op for non-SHARED_SCHEMA connections, or if bRelease
** is zero. Otherwise, clear the DBFLAG_SchemaInuse flag and release all
** schema references currently held.
*/
void sqlite3UnlockReusableSchema(sqlite3 *db, int bRelease){
  if( bRelease ){
    db->mDbFlags &= ~DBFLAG_SchemaInuse;
    sqlite3SchemaReleaseAll(db);
  }
}
#endif /* ifdef SQLITE_ENABLE_SHARED_SCHEMA */

/*
** Initialize all database files - the main database file, the file
** used to store temporary tables, and any additional database files
** created using ATTACH statements.  Return a success code.  If an
** error occurs, write an error message into *pzErrMsg.
**

#define AUTOEQP_off      0           /* Automatic EXPLAIN QUERY PLAN is off */
#define AUTOEQP_on       1           /* Automatic EQP is on */
#define AUTOEQP_trigger  2           /* On and also show plans for triggers */
#define AUTOEQP_full     3           /* Show full EXPLAIN */

/* Allowed values for ShellState.openMode
*/
#define SHELL_OPEN_UNSPEC       0    /* No open-mode specified */
#define SHELL_OPEN_NORMAL       1    /* Normal database file */
#define SHELL_OPEN_APPENDVFS    2    /* Use appendvfs */
#define SHELL_OPEN_ZIPFILE      3    /* Use the zipfile virtual table */
#define SHELL_OPEN_READONLY     4    /* Open a normal database read-only */
#define SHELL_OPEN_DESERIALIZE  5    /* Open using sqlite3_deserialize() */
#define SHELL_OPEN_HEXDB        6    /* Use "dbtotxt" output as data source */
#define SHELL_OPEN_SHAREDSCHEMA 7    /* Open for schema reuse */

/* Allowed values for ShellState.eTraceType
*/
#define SHELL_TRACE_PLAIN      0      /* Show input SQL text */
#define SHELL_TRACE_EXPANDED   1      /* Show expanded SQL text */
#define SHELL_TRACE_NORMALIZED 2      /* Show normalized SQL text */

        sqlite3_open(":memory:", &p->db);
        break;
      }
      case SHELL_OPEN_READONLY: {
        sqlite3_open_v2(p->zDbFilename, &p->db, SQLITE_OPEN_READONLY, 0);
        break;
      }
      case SHELL_OPEN_SHAREDSCHEMA: {
        sqlite3_open_v2(p->zDbFilename, &p->db,
          SQLITE_OPEN_READWRITE|SQLITE_OPEN_CREATE|SQLITE_OPEN_SHARED_SCHEMA,0);
        break;
      }
      case SHELL_OPEN_UNSPEC:
      case SHELL_OPEN_NORMAL: {
        sqlite3_open(p->zDbFilename, &p->db);

      }else if( optionMatch(z, "zip") ){
        p->openMode = SHELL_OPEN_ZIPFILE;
#endif
      }else if( optionMatch(z, "append") ){
        p->openMode = SHELL_OPEN_APPENDVFS;
      }else if( optionMatch(z, "readonly") ){
        p->openMode = SHELL_OPEN_READONLY;
      }else if( optionMatch(z, "sharedschema") ){
        p->openMode = SHELL_OPEN_SHAREDSCHEMA;
      }else if( z[0]=='-' ){
#ifdef SQLITE_ENABLE_DESERIALIZE
      }else if( optionMatch(z, "deserialize") ){
        p->openMode = SHELL_OPEN_DESERIALIZE;
      }else if( optionMatch(z, "hexdb") ){
        p->openMode = SHELL_OPEN_HEXDB;
      }else if( optionMatch(z, "maxsize") && iName+1<nArg ){

    }else if( strcmp(z,"-deserialize")==0 ){
      data.openMode = SHELL_OPEN_DESERIALIZE;
    }else if( strcmp(z,"-maxsize")==0 && i+1<argc ){
      data.szMax = integerValue(argv[++i]);
#endif
    }else if( strcmp(z,"-readonly")==0 ){
      data.openMode = SHELL_OPEN_READONLY;
    }else if( strcmp(z,"-sharedschema")==0 ){
      data.openMode = SHELL_OPEN_SHAREDSCHEMA;
#if !defined(SQLITE_OMIT_VIRTUALTABLE) && defined(SQLITE_HAVE_ZLIB)
    }else if( strncmp(z, "-A",2)==0 ){
      /* All remaining command-line arguments are passed to the ".archive"
      ** command, so ignore them */
      break;
#endif
    }else if( strcmp(z, "-memtrace")==0 ){

    }else if( strcmp(z,"-deserialize")==0 ){
      data.openMode = SHELL_OPEN_DESERIALIZE;
    }else if( strcmp(z,"-maxsize")==0 && i+1<argc ){
      data.szMax = integerValue(argv[++i]);
#endif
    }else if( strcmp(z,"-readonly")==0 ){
      data.openMode = SHELL_OPEN_READONLY;
    }else if( strcmp(z,"-sharedschema")==0 ){
      data.openMode = SHELL_OPEN_SHAREDSCHEMA;
    }else if( strcmp(z,"-ascii")==0 ){
      data.mode = MODE_Ascii;
      sqlite3_snprintf(sizeof(data.colSeparator), data.colSeparator,
                       SEP_Unit);
      sqlite3_snprintf(sizeof(data.rowSeparator), data.rowSeparator,
                       SEP_Record);
    }else if( strcmp(z,"-separator")==0 ){

*/
struct Db {
  char *zDbSName;      /* Name of this database. (schema name, not filename) */
  Btree *pBt;          /* The B*Tree structure for this database file */
  u8 safety_level;     /* How aggressive at syncing data to disk */
  u8 bSyncSet;         /* True if "PRAGMA synchronous=N" has been run */
  Schema *pSchema;     /* Pointer to database schema (possibly shared) */
#ifdef SQLITE_ENABLE_SHARED_SCHEMA
  SchemaPool *pSPool;  /* For REUSE_SCHEMA mode */
  VTable *pVTable;     /* List of all VTable objects (REUSE_SCHEMA mode only) */
#endif
};

/*
** An instance of the following structure stores a database schema.
**
** Most Schema objects are associated with a Btree.  The exception is
** the Schema for the TEMP databaes (sqlite3.aDb[1]) which is free-standing.

  Hash trigHash;       /* All triggers indexed by name */
  Hash fkeyHash;       /* All foreign keys by referenced table name */
  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 schemaFlags;     /* Flags associated with this schema */
  int cache_size;      /* Number of pages to use in the cache */
#ifdef SQLITE_ENABLE_SHARED_SCHEMA
  Schema *pNext;       /* Next Schema object SchemaPool (REUSE_SCHEMA) */
#endif
};

/*
** These macros can be used to test, set, or clear bits in the
** Db.pSchema->flags field.
*/
#define DbHasProperty(D,I,P)     (((D)->aDb[I].pSchema->schemaFlags&(P))==(P))

  sqlite3 *pNextBlocked;        /* Next in list of all blocked connections */
#endif
#ifdef SQLITE_USER_AUTHENTICATION
  sqlite3_userauth auth;        /* User authentication information */
#endif
};

#ifdef SQLITE_ENABLE_SHARED_SCHEMA
# define IsSharedSchema(db) (((db)->openFlags & SQLITE_OPEN_SHARED_SCHEMA)!=0)
#else
# define IsSharedSchema(db) 0
#endif

/*
** A macro to discover the encoding of a database.
*/
#define SCHEMA_ENC(db) ((db)->aDb[0].pSchema->enc)
#define ENC(db)        ((db)->enc)

  sqlite3 *db;              /* Database connection associated with this table */
  Module *pMod;             /* Pointer to module implementation */
  sqlite3_vtab *pVtab;      /* Pointer to vtab instance */
  int nRef;                 /* Number of pointers to this structure */
  u8 bConstraint;           /* True if constraints are supported */
  int iSavepoint;           /* Depth of the SAVEPOINT stack */
  VTable *pNext;            /* Next in linked list (see above) */
#ifdef SQLITE_ENABLE_SHARED_SCHEMA
  char *zName;              /* Table name (REUSE_SCHEMA mode) */
#endif
};

/*
** The schema for each SQL table and view is represented in memory
** by an instance of the following structure.
*/
struct Table {

  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 expression (may be NULL) */
  IdList *pColumns;       /* If this is an UPDATE OF <column-list> trigger,
                             the <column-list> is stored here */
  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 */
#ifdef SQLITE_ENABLE_SHARED_SCHEMA
  char *zTabSchema;       /* Temp triggers in IsSharedSchema() dbs only */
#endif
};

/*
** 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.

int sqlite3FindDbName(sqlite3 *, const char *);
int sqlite3AnalysisLoad(sqlite3*,int iDB);
void sqlite3DeleteIndexSamples(sqlite3*,Index*);
void sqlite3DefaultRowEst(Index*);
void sqlite3RegisterLikeFunctions(sqlite3*, int);
int sqlite3IsLikeFunction(sqlite3*,Expr*,int*,char*);
void sqlite3SchemaClear(void *);
void sqlite3SchemaClearOrDisconnect(sqlite3*, int);

#ifdef SQLITE_ENABLE_SHARED_SCHEMA 
int sqlite3SchemaConnect(sqlite3*, int, u64);
int sqlite3SchemaDisconnect(sqlite3 *, int, int);

Schema *sqlite3SchemaExtract(SchemaPool*);
int sqlite3SchemaLoad(sqlite3*, int, int*, char**);
void sqlite3SchemaReleaseAll(sqlite3*);
void sqlite3SchemaRelease(sqlite3*, int);
void sqlite3SchemaAdjustUsed(sqlite3*, int, int, int*);
void sqlite3SchemaWritable(Parse*, int);
void sqlite3UnlockReusableSchema(sqlite3 *db, int bRelease);
int sqlite3LockReusableSchema(sqlite3 *db);
#else
# define sqlite3SchemaWritable(x,y)
# define sqlite3UnlockReusableSchema(x,y)
# define sqlite3LockReusableSchema(x) 0
# define sqlite3SchemaDisconnect(x,y,z) SQLITE_OK
# define sqlite3SchemaLoad(w,x,y,z) SQLITE_OK
# define sqlite3SchemaRelease(y,z)
# define sqlite3SchemaConnect(x,y,z) SQLITE_OK
#endif

Schema *sqlite3SchemaGet(sqlite3 *, Btree *);
int sqlite3SchemaToIndex(sqlite3 *db, Schema *);
KeyInfo *sqlite3KeyInfoAlloc(sqlite3*,int,int);
void sqlite3KeyInfoUnref(KeyInfo*);
KeyInfo *sqlite3KeyInfoRef(KeyInfo*);
KeyInfo *sqlite3KeyInfoOfIndex(Parse*, Index*);
KeyInfo *sqlite3KeyInfoFromExprList(Parse*, ExprList*, int, int);




#ifdef SQLITE_DEBUG
int sqlite3KeyInfoIsWriteable(KeyInfo*);
#endif
int sqlite3CreateFunc(sqlite3 *, const char *, int, int, void *,
  void (*)(sqlite3_context*,int,sqlite3_value **),
  void (*)(sqlite3_context*,int,sqlite3_value **), 

      int nByte = 0;              /* Used to accumulate return value */
      int bReleaseSchema;

      sqlite3BtreeEnterAll(db);
      bReleaseSchema = sqlite3LockReusableSchema(db);
      db->pnBytesFreed = &nByte;
      for(i=0; i<db->nDb; i++){
        Schema *pSchema;
#ifdef SQLITE_ENABLE_SHARED_SCHEMA
        int bUnload = 0;
        int nUsed = nByte;

        if( db->aDb[i].pSPool ){
          char *zDummy = 0;
          rc = sqlite3SchemaLoad(db, i, &bUnload, &zDummy);
          sqlite3_free(zDummy);
          if( rc ) break;
        }
#endif /* ifdef SQLITE_ENABLE_SHARED_SCHEMA */
        pSchema = db->aDb[i].pSchema;
        if( ALWAYS(pSchema!=0) ){
          HashElem *p;

          nByte += sqlite3GlobalConfig.m.xRoundup(sizeof(HashElem)) * (
              pSchema->tblHash.count 
            + pSchema->trigHash.count

          for(p=sqliteHashFirst(&pSchema->trigHash); p; p=sqliteHashNext(p)){
            sqlite3DeleteTrigger(db, (Trigger*)sqliteHashData(p));
          }
          for(p=sqliteHashFirst(&pSchema->tblHash); p; p=sqliteHashNext(p)){
            sqlite3DeleteTable(db, (Table *)sqliteHashData(p));
          }
        }
#ifdef SQLITE_ENABLE_SHARED_SCHEMA
        if( db->aDb[i].pSPool ){
          if( bUnload ) sqlite3SchemaRelease(db, i);
          sqlite3SchemaAdjustUsed(db, i, nUsed, &nByte);
        }
#endif /* ifdef SQLITE_ENABLE_SHARED_SCHEMA */
      }
      sqlite3UnlockReusableSchema(db, bReleaseSchema);
      db->pnBytesFreed = 0;
      sqlite3BtreeLeaveAll(db);

      *pHighwater = 0;
      *pCurrent = nByte;

static int sqliteCmdUsage(
  Tcl_Interp *interp,
  Tcl_Obj *const*objv
){
  Tcl_WrongNumArgs(interp, 1, objv,
    "HANDLE ?FILENAME? ?-vfs VFSNAME? ?-readonly BOOLEAN? ?-create BOOLEAN?"
    " ?-nomutex BOOLEAN? ?-fullmutex BOOLEAN? ?-uri BOOLEAN?"
#ifdef SQLITE_ENABLE_SHARED_SCHEMA
    " ?-shared-schema BOOLEAN?"
#endif
#if defined(SQLITE_HAS_CODEC) && !defined(SQLITE_OMIT_CODEC_FROM_TCL)
    " ?-key CODECKEY?"
#endif
  );
  return TCL_ERROR;
}

      int b;
      if( Tcl_GetBooleanFromObj(interp, objv[i], &b) ) return TCL_ERROR;
      if( b ){
        flags |= SQLITE_OPEN_URI;
      }else{
        flags &= ~SQLITE_OPEN_URI;
      }
#ifdef SQLITE_ENABLE_SHARED_SCHEMA
    }else if( strcmp(zArg, "-shared-schema")==0 ){
      int b;
      if( Tcl_GetBooleanFromObj(interp, objv[i], &b) ) return TCL_ERROR;
      if( b ){
        flags |= SQLITE_OPEN_SHARED_SCHEMA;
      }else{
        flags &= ~SQLITE_OPEN_SHARED_SCHEMA;
      }
#endif /* ifdef SQLITE_ENABLE_SHARED_SCHEMA */
    }else{
      Tcl_AppendResult(interp, "unknown option: ", zArg, (char*)0);
      return TCL_ERROR;
    }
  }
  zErrMsg = 0;
  p = (SqliteDb*)Tcl_Alloc( sizeof(*p) );

#endif

#ifdef SQLITE_OMIT_WINDOWFUNC
  Tcl_SetVar2(interp, "sqlite_options", "windowfunc", "0", TCL_GLOBAL_ONLY);
#else
  Tcl_SetVar2(interp, "sqlite_options", "windowfunc", "1", TCL_GLOBAL_ONLY);
#endif

#ifdef SQLITE_ENABLE_SHARED_SCHEMA
  Tcl_SetVar2(interp, "sqlite_options", "sharedschema", "1", TCL_GLOBAL_ONLY);
#else
  Tcl_SetVar2(interp, "sqlite_options", "sharedschema", "0", TCL_GLOBAL_ONLY);
#endif

#define LINKVAR(x) { \
    static const int cv_ ## x = SQLITE_ ## x; \
    Tcl_LinkVar(interp, "SQLITE_" #x, (char *)&(cv_ ## x), \
                TCL_LINK_INT | TCL_LINK_READ_ONLY); }

  LINKVAR( MAX_LENGTH );

*/

/*
** None of this works unless we have virtual tables.
*/
#if !defined(SQLITE_OMIT_VIRTUALTABLE) && defined(SQLITE_TEST)

#include <tcl.h>

#ifdef SQLITE_ENABLE_SHARED_SCHEMA

#include "sqliteInt.h"

/* The code in this file defines a sqlite3 virtual-table module with
** the following schema.
*/
#define SCHEMAPOOL_SCHEMA \
"CREATE TABLE x("         \
"  cksum   INTEGER, "     \

  if( getDbPointer(interp, Tcl_GetString(objv[1]), &db) ) return TCL_ERROR;
#ifndef SQLITE_OMIT_VIRTUALTABLE
  sqlite3_create_module(db, "schemapool", &schemaPoolModule, 0);
#endif
  return TCL_OK;
}

#endif /* ifdef SQLITE_ENABLE_SHARED_SCHEMA */
#endif /* !defined(SQLITE_OMIT_VIRTUALTABLE) && defined(SQLITE_TEST) */

/*
** Register commands with the TCL interpreter.
*/
int Sqlitetestschemapool_Init(Tcl_Interp *interp){
#ifdef SQLITE_ENABLE_SHARED_SCHEMA
  static struct {
     char *zName;
     Tcl_ObjCmdProc *xProc;
     void *clientData;
  } aObjCmd[] = {
     { "register_schemapool_module", register_schemapool_module, 0 },
  };
  int i;
  for(i=0; i<sizeof(aObjCmd)/sizeof(aObjCmd[0]); i++){
    Tcl_CreateObjCommand(interp, aObjCmd[i].zName, 
        aObjCmd[i].xProc, aObjCmd[i].clientData, 0);
  }
#endif /* ifdef SQLITE_ENABLE_SHARED_SCHEMA */
  return TCL_OK;
}

  if( pParse->disableTriggers ){
    return 0;
  }

  if( pTmpSchema!=pTab->pSchema ){
    sqlite3 *db = pParse->db;
    HashElem *p;
#ifdef SQLITE_ENABLE_SHARED_SCHEMA
    char *zSchema = 0;
    if( IsSharedSchema(db) ){
      zSchema = db->aDb[sqlite3SchemaToIndex(db, pTab->pSchema)].zDbSName;
    }
#endif
    assert( sqlite3SchemaMutexHeld(db, 0, pTmpSchema) );
    for(p=sqliteHashFirst(&pTmpSchema->trigHash); p; p=sqliteHashNext(p)){
      Trigger *pTrig = (Trigger *)sqliteHashData(p);

#ifdef SQLITE_ENABLE_SHARED_SCHEMA
      if( (zSchema==0 && pTrig->pTabSchema==pTab->pSchema)
       || (zSchema!=0 && 0==sqlite3StrICmp(pTrig->zTabSchema, zSchema)) )

#else 
      if( pTrig->pTabSchema==pTab->pSchema )
#endif
      {
        if( 0==sqlite3StrICmp(pTrig->table, pTab->zName) ){

          pTrig->pTabSchema = pTab->pSchema;
          pTrig->pNext = (pList ? pList : pTab->pTrigger);
          pList = pTrig;
        }
      }
    }
  }

  /* Build the Trigger object */
  pTrigger = (Trigger*)sqlite3DbMallocZero(db, sizeof(Trigger));
  if( pTrigger==0 ) goto trigger_cleanup;
  pTrigger->zName = zName;
  zName = 0;
  pTrigger->table = sqlite3DbStrDup(db, pTableName->a[0].zName);
#ifdef SQLITE_ENABLE_SHARED_SCHEMA
  if( IsSharedSchema(db) && iDb==1 ){
    int iTabDb = sqlite3SchemaToIndex(db, pTab->pSchema);
    pTrigger->zTabSchema = sqlite3DbStrDup(db, db->aDb[iTabDb].zDbSName);
  }
#endif /* ifdef SQLITE_ENABLE_SHARED_SCHEMA */
  pTrigger->pSchema = db->aDb[iDb].pSchema;
  pTrigger->pTabSchema = pTab->pSchema;
  pTrigger->op = (u8)op;
  pTrigger->tr_tm = tr_tm==TK_BEFORE ? TRIGGER_BEFORE : TRIGGER_AFTER;
  if( IN_RENAME_OBJECT ){
    sqlite3RenameTokenRemap(pParse, pTrigger->table, pTableName->a[0].zName);
    pTrigger->pWhen = pWhen;

** Recursively delete a Trigger structure
*/
void sqlite3DeleteTrigger(sqlite3 *db, Trigger *pTrigger){
  if( pTrigger==0 ) return;
  sqlite3DeleteTriggerStep(db, pTrigger->step_list);
  sqlite3DbFree(db, pTrigger->zName);
  sqlite3DbFree(db, pTrigger->table);
#ifdef SQLITE_ENABLE_SHARED_SCHEMA
  sqlite3DbFree(db, pTrigger->zTabSchema);
#endif
  sqlite3ExprDelete(db, pTrigger->pWhen);
  sqlite3IdListDelete(db, pTrigger->pColumns);
  sqlite3DbFree(db, pTrigger);
}

/*
** This function is called to drop a trigger from the database schema. 

** pTab is a pointer to a Table structure representing a virtual-table.
** Return a pointer to the VTable object used by connection db to access 
** this virtual-table, if one has been created, or NULL otherwise.
*/
VTable *sqlite3GetVTable(sqlite3 *db, Table *pTab){
  VTable *pVtab;
  assert( IsVirtual(pTab) );
#ifdef SQLITE_ENABLE_SHARED_SCHEMA
  if( IsSharedSchema(db) ){
    int iDb = sqlite3SchemaToIndex(db, pTab->pSchema);
    if( iDb!=1 ){
      for(pVtab=db->aDb[iDb].pVTable; pVtab; pVtab=pVtab->pNext){
        if( sqlite3StrICmp(pTab->zName, pVtab->zName)==0 ) break;
      }
      return pVtab;
    }
  }
#endif /* ifdef SQLITE_ENABLE_SHARED_SCHEMA */
  for(pVtab=pTab->pVTable; pVtab && pVtab->db!=db; pVtab=pVtab->pNext);
  return pVtab;
}

/*
** Decrement the ref-count on a virtual table object. When the ref-count
** reaches zero, call the xDisconnect() method to delete the object.

  }

  zModuleName = sqlite3DbStrDup(db, pTab->zName);
  if( !zModuleName ){
    return SQLITE_NOMEM_BKPT;
  }

  nByte = sizeof(VTable);
#ifdef SQLITE_ENABLE_SHARED_SCHEMA
  nByte += sqlite3Strlen30(pTab->zName) + 1;
#endif
  pVTable = (VTable*)sqlite3MallocZero(nByte);
  if( !pVTable ){
    sqlite3OomFault(db);
    sqlite3DbFree(db, zModuleName);
    return SQLITE_NOMEM_BKPT;
  }
  pVTable->db = db;
  pVTable->pMod = pMod;
#ifdef SQLITE_ENABLE_SHARED_SCHEMA
  pVTable->zName = (char*)&pVTable[1];
  memcpy(pVTable->zName, pTab->zName, nByte-sizeof(VTable));
#endif

  iDb = sqlite3SchemaToIndex(db, pTab->pSchema);
  pTab->azModuleArg[1] = db->aDb[iDb].zDbSName;

  /* Invoke the virtual table constructor */
  assert( &db->pVtabCtx );
  assert( xConstruct );

      /* If everything went according to plan, link the new VTable structure
      ** into the linked list headed by pTab->pVTable. Or, if this is a
      ** reusable schema, into the linked list headed by Db.pVTable.
      **
      ** Then loop through the columns of the table to see if any of them
      ** contain the token "hidden". If so, set the Column COLFLAG_HIDDEN flag
      ** and remove the token from the type string.  */
#ifdef SQLITE_ENABLE_SHARED_SCHEMA
      if( IsSharedSchema(db) && iDb!=1 ){
        pVTable->pNext = db->aDb[iDb].pVTable;
        db->aDb[iDb].pVTable = pVTable;
      }else
#endif /* ifdef SQLITE_ENABLE_SHARED_SCHEMA */
      {
        pVTable->pNext = pTab->pVTable;
        pTab->pVTable = pVTable;
      }

      for(iCol=0; iCol<pTab->nCol; iCol++){
        char *zType = sqlite3ColumnType(&pTab->aCol[iCol], "");
        int nType;

#


set testdir [file dirname $argv0]
source $testdir/tester.tcl
set testprefix reuse1

ifcapable !sharedschema {
  finish_test
  return
}

forcedelete test.db2
sqlite3 db2 test.db2

do_execsql_test 1.0 {
  CREATE TABLE t1(x INTEGER PRIMARY KEY, y UNIQUE, z);
  CREATE INDEX i1 ON t1(z);

  do_execsql_test 2.2 {
    SELECT * FROM aux.ft;
  } {aux1 aux2 aux3}

  do_execsql_test 2.2 {
    SELECT * FROM aux.ft_content;
  } {1 aux1 2 aux2 3 aux3}


}

#-------------------------------------------------------------------------
#
reset_db
forcedelete test.db2
do_execsql_test 3.0 {

#
#


set testdir [file dirname $argv0]
source $testdir/tester.tcl
set testprefix reuse2

ifcapable !sharedschema {
  finish_test
  return
}

do_execsql_test 1.0 {
  CREATE TABLE t1(x INTEGER PRIMARY KEY, y UNIQUE, z);
  CREATE INDEX i1 ON t1(z);
  PRAGMA schema_version;
} {2}

#
#


set testdir [file dirname $argv0]
source $testdir/tester.tcl
set testprefix reuse3

ifcapable !sharedschema {
  finish_test
  return
}

do_execsql_test 1.0 {
  CREATE TABLE t1(x INTEGER PRIMARY KEY, y UNIQUE, z);
  CREATE INDEX i1 ON t1(z);
  CREATE TABLE t2(a);
} {}

#***********************************************************************
#
#

set testdir [file dirname $argv0]
source $testdir/tester.tcl
set testprefix reuse4

ifcapable !sharedschema {
  finish_test
  return
}

foreach {tn sharedschema} {
  1 0  
  2 1  
} {
  reset_db

#
#

set testdir [file dirname $argv0]
source $testdir/tester.tcl
set testprefix reuse5
set CLI [test_find_cli]

ifcapable !sharedschema {
  finish_test
  return
}

do_execsql_test 1.0 {
  CREATE TABLE t1(x, y);
  CREATE TABLE t2(a, b, c);
  CREATE INDEX t1x ON t1(x);
  CREATE INDEX t1y ON t1(y);
  CREATE VIEW v1 AS SELECT * FROM t2;

#***********************************************************************
#
#

set testdir [file dirname $argv0]
source $testdir/tester.tcl
set testprefix reusefault

ifcapable !sharedschema {
  finish_test
  return
}

do_execsql_test 1.0 {
  PRAGMA cache_size = 10;
  CREATE TABLE t1(a UNIQUE, b UNIQUE);
  INSERT INTO t1 VALUES(1, 2), (3, 4);
}
faultsim_save_and_close

set testdir [file dirname $argv0]
source $testdir/tester.tcl
set testprefix tcl

# Check the error messages generated by tclsqlite
#
set r "sqlite_orig HANDLE ?FILENAME? ?-vfs VFSNAME? ?-readonly BOOLEAN? ?-create BOOLEAN? ?-nomutex BOOLEAN? ?-fullmutex BOOLEAN? ?-uri BOOLEAN?"
ifcapable sharedschema {
  append r " ?-shared-schema BOOLEAN?"
}
if {[sqlite3 -has-codec]} {
  append r " ?-key CODECKEY?"
}
do_test tcl-1.1 {
  set v [catch {sqlite3 -bogus} msg]
  regsub {really_sqlite3} $msg {sqlite3} msg
  lappend v $msg