Esempio n. 1
0
/*
** Load the content of the sqlite_stat1 table into the index hash tables.
*/
int sqlite3AnalysisLoad(sqlite3 *db, int iDb){
  analysisInfo sInfo;
  HashElem *i;
  char *zSql;
  int rc;

  assert( iDb>=0 && iDb<db->nDb );
  assert( db->aDb[iDb].pBt!=0 );
  assert( sqlite3BtreeHoldsMutex(db->aDb[iDb].pBt) );

  /* Clear any prior statistics */
  for(i=sqliteHashFirst(&db->aDb[iDb].pSchema->idxHash);i;i=sqliteHashNext(i)){
    Index *pIdx = sqliteHashData(i);
    sqlite3DefaultRowEst(pIdx);
  }

  /* Check to make sure the sqlite_stat1 table existss */
  sInfo.db = db;
  sInfo.zDatabase = db->aDb[iDb].zName;
  if( sqlite3FindTable(db, "sqlite_stat1", sInfo.zDatabase)==0 ){
     return SQLITE_ERROR;
  }


  /* Load new statistics out of the sqlite_stat1 table */
  zSql = sqlite3MPrintf(db, "SELECT idx, stat FROM %Q.sqlite_stat1",
                        sInfo.zDatabase);
  sqlite3SafetyOff(db);
  rc = sqlite3_exec(db, zSql, analysisLoader, &sInfo, 0);
  sqlite3SafetyOn(db);
  sqlite3_free(zSql);
  return rc;
}
Esempio n. 2
0
/*
** This function is invoked by the vdbe to call the xCreate method
** of the virtual table named zTab in database iDb. 
**
** If an error occurs, *pzErr is set to point to an English language
** description of the error and an SQLITE_XXX error code is returned.
** In this case the caller must call sqlite3DbFree(db, ) on *pzErr.
*/
int sqlite3VtabCallCreate(sqlite3 *db, int iDb, const char *zTab, char **pzErr){
  int rc = SQLITE_OK;
  Table *pTab;
  Module *pMod;
  const char *zMod;

  pTab = sqlite3FindTable(db, zTab, db->aDb[iDb].zDbSName);
  assert( pTab && (pTab->tabFlags & TF_Virtual)!=0 && !pTab->pVTable );

  /* Locate the required virtual table module */
  zMod = pTab->azModuleArg[0];
  pMod = (Module*)sqlite3HashFind(&db->aModule, zMod);

  /* If the module has been registered and includes a Create method, 
  ** invoke it now. If the module has not been registered, return an 
  ** error. Otherwise, do nothing.
  */
  if( pMod==0 || pMod->pModule->xCreate==0 || pMod->pModule->xDestroy==0 ){
    *pzErr = sqlite3MPrintf(db, "no such module: %s", zMod);
    rc = SQLITE_ERROR;
  }else{
    rc = vtabCallConstructor(db, pTab, pMod, pMod->pModule->xCreate, pzErr);
  }

  /* Justification of ALWAYS():  The xConstructor method is required to
  ** create a valid sqlite3_vtab if it returns SQLITE_OK. */
  if( rc==SQLITE_OK && ALWAYS(sqlite3GetVTable(db, pTab)) ){
    rc = growVTrans(db);
    if( rc==SQLITE_OK ){
      addToVTrans(db, sqlite3GetVTable(db, pTab));
    }
  }

  return rc;
}
Esempio n. 3
0
/*
** This function is invoked by the vdbe to call the xDestroy method
** of the virtual table named zTab in database iDb. This occurs
** when a DROP TABLE is mentioned.
**
** This call is a no-op if zTab is not a virtual table.
*/
int sqlite3VtabCallDestroy(sqlite3 *db, int iDb, const char *zTab){
  int rc = SQLITE_OK;
  Table *pTab;

  pTab = sqlite3FindTable(db, zTab, db->aDb[iDb].zDbSName);
  if( pTab!=0 && ALWAYS(pTab->pVTable!=0) ){
    VTable *p;
    int (*xDestroy)(sqlite3_vtab *);
    for(p=pTab->pVTable; p; p=p->pNext){
      assert( p->pVtab );
      if( p->pVtab->nRef>0 ){
        return SQLITE_LOCKED;
      }
    }
    p = vtabDisconnectAll(db, pTab);
    xDestroy = p->pMod->pModule->xDestroy;
    assert( xDestroy!=0 );  /* Checked before the virtual table is created */
    rc = xDestroy(p->pVtab);
    /* Remove the sqlite3_vtab* from the aVTrans[] array, if applicable */
    if( rc==SQLITE_OK ){
      assert( pTab->pVTable==p && p->pNext==0 );
      p->pVtab = 0;
      pTab->pVTable = 0;
      sqlite3VtabUnlock(p);
    }
  }

  return rc;
}
Esempio n. 4
0
/*
** This function is invoked by the vdbe to call the xCreate method
** of the virtual table named zTab in database iDb. 
**
** If an error occurs, *pzErr is set to point an an English language
** description of the error and an SQLITE_XXX error code is returned.
** In this case the caller must call sqliteFree() on *pzErr.
*/
int sqlite3VtabCallCreate(sqlite3 *db, int iDb, const char *zTab, char **pzErr){
  int rc = SQLITE_OK;
  Table *pTab;
  Module *pMod;
  const char *zModule;

  pTab = sqlite3FindTable(db, zTab, db->aDb[iDb].zName);
  assert(pTab && pTab->isVirtual && !pTab->pVtab);
  pMod = pTab->pMod;
  zModule = pTab->azModuleArg[0];

  /* If the module has been registered and includes a Create method, 
  ** invoke it now. If the module has not been registered, return an 
  ** error. Otherwise, do nothing.
  */
  if( !pMod ){
    *pzErr = sqlite3MPrintf("no such module: %s", zModule);
    rc = SQLITE_ERROR;
  }else{
    rc = vtabCallConstructor(db, pTab, pMod, pMod->pModule->xCreate, pzErr);
  }

  if( rc==SQLITE_OK && pTab->pVtab ){
      rc = addToVTrans(db, pTab->pVtab);
  }

  return rc;
}
Esempio n. 5
0
/*
** Load the content of the sqlite_stat1 table into the index hash tables.
*/
void sqlite3AnalysisLoad(sqlite3 *db, int iDb){
  analysisInfo sInfo;
  HashElem *i;
  char *zSql;

  /* Clear any prior statistics */
  for(i=sqliteHashFirst(&db->aDb[iDb].pSchema->idxHash);i;i=sqliteHashNext(i)){
    Index *pIdx = sqliteHashData(i);
    sqlite3DefaultRowEst(pIdx);
  }

  /* Check to make sure the sqlite_stat1 table existss */
  sInfo.db = db;
  sInfo.zDatabase = db->aDb[iDb].zName;
  if( sqlite3FindTable(db, "sqlite_stat1", sInfo.zDatabase)==0 ){
     return;
  }


  /* Load new statistics out of the sqlite_stat1 table */
  zSql = sqlite3MPrintf("SELECT idx, stat FROM %Q.sqlite_stat1",
                        sInfo.zDatabase);
  sqlite3SafetyOff(db);
  sqlite3_exec(db, zSql, analysisLoader, &sInfo, 0);
  sqlite3SafetyOn(db);
  sqliteFree(zSql);
}
Esempio n. 6
0
/*
** This routine generates code that opens the sqlite_stat1 table on cursor
** iStatCur.
**
** If the sqlite_stat1 tables does not previously exist, it is created.
** If it does previously exist, all entires associated with table zWhere
** are removed.  If zWhere==0 then all entries are removed.
*/
static void openStatTable(
  Parse *pParse,          /* Parsing context */
  int iDb,                /* The database we are looking in */
  int iStatCur,           /* Open the sqlite_stat1 table on this cursor */
  const char *zWhere      /* Delete entries associated with this table */
){
  sqlite3 *db = pParse->db;
  Db *pDb;
  int iRootPage;
  Table *pStat;
  Vdbe *v = sqlite3GetVdbe(pParse);

  if( v==0 ) return;
  assert( sqlite3BtreeHoldsAllMutexes(db) );
  assert( sqlite3VdbeDb(v)==db );
  pDb = &db->aDb[iDb];
  if( (pStat = sqlite3FindTable(db, "sqlite_stat1", pDb->zName))==0 ){
    /* The sqlite_stat1 tables does not exist.  Create it.  
    ** Note that a side-effect of the CREATE TABLE statement is to leave
    ** the rootpage of the new table on the top of the stack.  This is
    ** important because the OpenWrite opcode below will be needing it. */
    sqlite3NestedParse(pParse,
      "CREATE TABLE %Q.sqlite_stat1(tbl,idx,stat)",
      pDb->zName
    );
    iRootPage = 0;  /* Cause rootpage to be taken from top of stack */
  }else if( zWhere ){
    /* The sqlite_stat1 table exists.  Delete all entries associated with
    ** the table zWhere. */
    sqlite3NestedParse(pParse,
       "DELETE FROM %Q.sqlite_stat1 WHERE tbl=%Q",
       pDb->zName, zWhere
    );
    iRootPage = pStat->tnum;
  }else{
    /* The sqlite_stat1 table already exists.  Delete all rows. */
    iRootPage = pStat->tnum;
    sqlite3VdbeAddOp(v, OP_Clear, pStat->tnum, iDb);
  }

  /* Open the sqlite_stat1 table for writing. Unless it was created
  ** by this vdbe program, lock it for writing at the shared-cache level. 
  ** If this vdbe did create the sqlite_stat1 table, then it must have 
  ** already obtained a schema-lock, making the write-lock redundant.
  */
  if( iRootPage>0 ){
    sqlite3TableLock(pParse, iDb, iRootPage, 1, "sqlite_stat1");
  }
  sqlite3VdbeAddOp(v, OP_Integer, iDb, 0);
  sqlite3VdbeAddOp(v, OP_OpenWrite, iStatCur, iRootPage);
  sqlite3VdbeAddOp(v, OP_SetNumColumns, iStatCur, 3);
}
Esempio n. 7
0
/*
** This routine generates code that opens the sqlite_stat1 table on cursor
** iStatCur.
**
** If the sqlite_stat1 tables does not previously exist, it is created.
** If it does previously exist, all entires associated with table zWhere
** are removed.  If zWhere==0 then all entries are removed.
*/
static void openStatTable(
  Parse *pParse,          /* Parsing context */
  int iDb,                /* The database we are looking in */
  int iStatCur,           /* Open the sqlite_stat1 table on this cursor */
  const char *zWhere      /* Delete entries associated with this table */
){
  sqlite3 *db = pParse->db;
  Db *pDb;
  int iRootPage;
  Table *pStat;
  Vdbe *v = sqlite3GetVdbe(pParse);

  pDb = &db->aDb[iDb];
  if( (pStat = sqlite3FindTable(db, "sqlite_stat1", pDb->zName))==0 ){
    /* The sqlite_stat1 tables does not exist.  Create it.  
    ** Note that a side-effect of the CREATE TABLE statement is to leave
    ** the rootpage of the new table on the top of the stack.  This is
    ** important because the OpenWrite opcode below will be needing it. */
    sqlite3NestedParse(pParse,
      "CREATE TABLE %Q.sqlite_stat1(tbl,idx,stat)",
      pDb->zName
    );
    iRootPage = 0;  /* Cause rootpage to be taken from top of stack */
  }else if( zWhere ){
    /* The sqlite_stat1 table exists.  Delete all entries associated with
    ** the table zWhere. */
    sqlite3NestedParse(pParse,
       "DELETE FROM %Q.sqlite_stat1 WHERE tbl=%Q",
       pDb->zName, zWhere
    );
    iRootPage = pStat->tnum;
  }else{
    /* The sqlite_stat1 table already exists.  Delete all rows. */
    iRootPage = pStat->tnum;
    sqlite3VdbeAddOp(v, OP_Clear, pStat->tnum, iDb);
  }

  /* Open the sqlite_stat1 table for writing.
  */
  sqlite3VdbeAddOp(v, OP_Integer, iDb, 0);
  sqlite3VdbeAddOp(v, OP_OpenWrite, iStatCur, iRootPage);
  sqlite3VdbeAddOp(v, OP_SetNumColumns, iStatCur, 3);
}
Esempio n. 8
0
/*
** This callback is invoked once for each index when reading the
** sqlite_stat1 table.  
**
**     argv[0] = name of the table
**     argv[1] = name of the index (might be NULL)
**     argv[2] = results of analysis - on integer for each column
**
** Entries for which argv[1]==NULL simply record the number of rows in
** the table.
*/
static int analysisLoader(void *pData, int argc, char **argv, char **NotUsed){
  analysisInfo *pInfo = (analysisInfo*)pData;
  Index *pIndex;
  Table *pTable;
  int i, c, n;
  unsigned int v;
  const char *z;

  assert( argc==3 );
  UNUSED_PARAMETER2(NotUsed, argc);

  if( argv==0 || argv[0]==0 || argv[2]==0 ){
    return 0;
  }
  pTable = sqlite3FindTable(pInfo->db, argv[0], pInfo->zDatabase);
  if( pTable==0 ){
    return 0;
  }
  if( argv[1] ){
    pIndex = sqlite3FindIndex(pInfo->db, argv[1], pInfo->zDatabase);
  }else{
    pIndex = 0;
  }
  n = pIndex ? pIndex->nColumn : 0;
  z = argv[2];
  for(i=0; *z && i<=n; i++){
    v = 0;
    while( (c=z[0])>='0' && c<='9' ){
      v = v*10 + c - '0';
      z++;
    }
    if( i==0 ) pTable->nRowEst = v;
    if( pIndex==0 ) break;
    pIndex->aiRowEst[i] = v;
    if( *z==' ' ) z++;
    if( memcmp(z, "unordered", 10)==0 ){
      pIndex->bUnordered = 1;
      break;
    }
  }
  return 0;
}
Esempio n. 9
0
/*
** This function is invoked by the vdbe to call the xDestroy method
** of the virtual table named zTab in database iDb. This occurs
** when a DROP TABLE is mentioned.
**
** This call is a no-op if zTab is not a virtual table.
*/
int sqlite3VtabCallDestroy(sqlite3 *db, int iDb, const char *zTab)
{
  int rc = SQLITE_OK;
  Table *pTab;

  pTab = sqlite3FindTable(db, zTab, db->aDb[iDb].zName);
  assert(pTab);
  if( pTab->pVtab ){
    int (*xDestroy)(sqlite3_vtab *pVTab) = pTab->pMod->pModule->xDestroy;
    rc = sqlite3SafetyOff(db);
    assert( rc==SQLITE_OK );
    if( xDestroy ){
      rc = xDestroy(pTab->pVtab);
    }
    sqlite3SafetyOn(db);
    if( rc==SQLITE_OK ){
      pTab->pVtab = 0;
    }
  }

  return rc;
}
Esempio n. 10
0
/*
** This function is invoked by the vdbe to call the xDestroy method
** of the virtual table named zTab in database iDb. This occurs
** when a DROP TABLE is mentioned.
**
** This call is a no-op if zTab is not a virtual table.
*/
int sqlite3VtabCallDestroy(sqlite3 *db, int iDb, const char *zTab){
  int rc = SQLITE_OK;
  Table *pTab;

  pTab = sqlite3FindTable(db, zTab, db->aDb[iDb].zName);
  if( ALWAYS(pTab!=0 && pTab->pVTable!=0) ){
    VTable *p = vtabDisconnectAll(db, pTab);

    assert( rc==SQLITE_OK );
    rc = p->pMod->pModule->xDestroy(p->pVtab);

    /* Remove the sqlite3_vtab* from the aVTrans[] array, if applicable */
    if( rc==SQLITE_OK ){
      assert( pTab->pVTable==p && p->pNext==0 );
      p->pVtab = 0;
      pTab->pVTable = 0;
      sqlite3VtabUnlock(p);
    }
  }

  return rc;
}
Esempio n. 11
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
** database.  iDb==1 should never be used.  iDb>=2 is used for
** auxiliary databases.  Return one of the SQLITE_ error codes to
** indicate success or failure.
*/
static int sqlite3InitOne(sqlite3 *db, int iDb, char **pzErrMsg){
  int rc;
  BtCursor *curMain;
  int size;
  Table *pTab;
  Db *pDb;
  char const *azArg[4];
  int meta[10];
  InitData initData;
  char const *zMasterSchema;
  char const *zMasterName = SCHEMA_TABLE(iDb);

  /*
  ** The master database table has a structure like this
  */
  static const char master_schema[] = 
     "CREATE TABLE sqlite_master(\n"
     "  type text,\n"
     "  name text,\n"
     "  tbl_name text,\n"
     "  rootpage integer,\n"
     "  sql text\n"
     ")"
  ;
#ifndef SQLITE_OMIT_TEMPDB
  static const char temp_master_schema[] = 
     "CREATE TEMP TABLE sqlite_temp_master(\n"
     "  type text,\n"
     "  name text,\n"
     "  tbl_name text,\n"
     "  rootpage integer,\n"
     "  sql text\n"
     ")"
  ;
#else
  #define temp_master_schema 0
#endif

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

  /* zMasterSchema and zInitScript are set to point at the master schema
  ** and initialisation script appropriate for the database being
  ** initialised. zMasterName is the name of the master table.
  */
  if( !OMIT_TEMPDB && iDb==1 ){
    zMasterSchema = temp_master_schema;
  }else{
    zMasterSchema = master_schema;
  }
  zMasterName = SCHEMA_TABLE(iDb);

  /* Construct the schema tables.  */
  azArg[0] = zMasterName;
  azArg[1] = "1";
  azArg[2] = zMasterSchema;
  azArg[3] = 0;
  initData.db = db;
  initData.iDb = iDb;
  initData.rc = SQLITE_OK;
  initData.pzErrMsg = pzErrMsg;
  (void)sqlite3SafetyOff(db);
  sqlite3InitCallback(&initData, 3, (char **)azArg, 0);
  (void)sqlite3SafetyOn(db);
  if( initData.rc ){
    rc = initData.rc;
    goto error_out;
  }
  pTab = sqlite3FindTable(db, zMasterName, db->aDb[iDb].zName);
  if( pTab ){
    pTab->tabFlags |= TF_Readonly;
  }

  /* Create a cursor to hold the database open
  */
  pDb = &db->aDb[iDb];
  if( pDb->pBt==0 ){
    if( !OMIT_TEMPDB && iDb==1 ){
      DbSetProperty(db, 1, DB_SchemaLoaded);
    }
    return SQLITE_OK;
  }
  curMain = sqlite3MallocZero(sqlite3BtreeCursorSize());
  if( !curMain ){
    rc = SQLITE_NOMEM;
    goto error_out;
  }
  sqlite3BtreeEnter(pDb->pBt);
  rc = sqlite3BtreeCursor(pDb->pBt, MASTER_ROOT, 0, 0, curMain);
  if( rc!=SQLITE_OK && rc!=SQLITE_EMPTY ){
    sqlite3SetString(pzErrMsg, db, "%s", sqlite3ErrStr(rc));
    goto initone_error_out;
  }

  /* Get the database meta information.
  **
  ** Meta values are as follows:
  **    meta[0]   Schema cookie.  Changes with each schema change.
  **    meta[1]   File format of schema layer.
  **    meta[2]   Size of the page cache.
  **    meta[3]   Use freelist if 0.  Autovacuum if greater than zero.
  **    meta[4]   Db text encoding. 1:UTF-8 2:UTF-16LE 3:UTF-16BE
  **    meta[5]   The user cookie. Used by the application.
  **    meta[6]   Incremental-vacuum flag.
  **    meta[7]
  **    meta[8]
  **    meta[9]
  **
  ** Note: The #defined SQLITE_UTF* symbols in sqliteInt.h correspond to
  ** the possible values of meta[4].
  */
  if( rc==SQLITE_OK ){
    int i;
    for(i=0; i<ArraySize(meta); i++){
      rc = sqlite3BtreeGetMeta(pDb->pBt, i+1, (u32 *)&meta[i]);
      if( rc ){
        sqlite3SetString(pzErrMsg, db, "%s", sqlite3ErrStr(rc));
        goto initone_error_out;
      }
    }
  }else{
    memset(meta, 0, sizeof(meta));
  }
  pDb->pSchema->schema_cookie = meta[0];

  /* If opening a non-empty database, check the text encoding. For the
  ** main database, set sqlite3.enc to the encoding of the main database.
  ** For an attached db, it is an error if the encoding is not the same
  ** as sqlite3.enc.
  */
  if( meta[4] ){  /* text encoding */
    if( iDb==0 ){
      /* If opening the main database, set ENC(db). */
      ENC(db) = (u8)meta[4];
      db->pDfltColl = sqlite3FindCollSeq(db, SQLITE_UTF8, "BINARY", 6, 0);
    }else{
      /* If opening an attached database, the encoding much match ENC(db) */
      if( meta[4]!=ENC(db) ){
        sqlite3SetString(pzErrMsg, db, "attached databases must use the same"
            " text encoding as main database");
        rc = SQLITE_ERROR;
        goto initone_error_out;
      }
    }
  }else{
    DbSetProperty(db, iDb, DB_Empty);
  }
  pDb->pSchema->enc = ENC(db);

  if( pDb->pSchema->cache_size==0 ){
    size = meta[2];
    if( size==0 ){ size = SQLITE_DEFAULT_CACHE_SIZE; }
    if( size<0 ) size = -size;
    pDb->pSchema->cache_size = size;
    sqlite3BtreeSetCacheSize(pDb->pBt, pDb->pSchema->cache_size);
  }

  /*
  ** file_format==1    Version 3.0.0.
  ** file_format==2    Version 3.1.3.  // ALTER TABLE ADD COLUMN
  ** file_format==3    Version 3.1.4.  // ditto but with non-NULL defaults
  ** file_format==4    Version 3.3.0.  // DESC indices.  Boolean constants
  */
  pDb->pSchema->file_format = (u8)meta[1];
  if( pDb->pSchema->file_format==0 ){
    pDb->pSchema->file_format = 1;
  }
  if( pDb->pSchema->file_format>SQLITE_MAX_FILE_FORMAT ){
    sqlite3SetString(pzErrMsg, db, "unsupported file format");
    rc = SQLITE_ERROR;
    goto initone_error_out;
  }

  /* Ticket #2804:  When we open a database in the newer file format,
  ** clear the legacy_file_format pragma flag so that a VACUUM will
  ** not downgrade the database and thus invalidate any descending
  ** indices that the user might have created.
  */
  if( iDb==0 && meta[1]>=4 ){
    db->flags &= ~SQLITE_LegacyFileFmt;
  }

  /* Read the schema information out of the schema tables
  */
  assert( db->init.busy );
  if( rc==SQLITE_EMPTY ){
    /* For an empty database, there is nothing to read */
    rc = SQLITE_OK;
  }else{
    char *zSql;
    zSql = sqlite3MPrintf(db, 
        "SELECT name, rootpage, sql FROM '%q'.%s",
        db->aDb[iDb].zName, zMasterName);
    (void)sqlite3SafetyOff(db);
#ifndef SQLITE_OMIT_AUTHORIZATION
    {
      int (*xAuth)(void*,int,const char*,const char*,const char*,const char*);
      xAuth = db->xAuth;
      db->xAuth = 0;
#endif
      rc = sqlite3_exec(db, zSql, sqlite3InitCallback, &initData, 0);
#ifndef SQLITE_OMIT_AUTHORIZATION
      db->xAuth = xAuth;
    }
#endif
    if( rc==SQLITE_OK ) rc = initData.rc;
    (void)sqlite3SafetyOn(db);
    sqlite3DbFree(db, zSql);
#ifndef SQLITE_OMIT_ANALYZE
    if( rc==SQLITE_OK ){
      sqlite3AnalysisLoad(db, iDb);
    }
#endif
  }
  if( db->mallocFailed ){
    rc = SQLITE_NOMEM;
    sqlite3ResetInternalSchema(db, 0);
  }
  if( rc==SQLITE_OK || (db->flags&SQLITE_RecoveryMode)){
    /* Black magic: If the SQLITE_RecoveryMode flag is set, then consider
    ** the schema loaded, even if errors occurred. In this situation the 
    ** current sqlite3_prepare() operation will fail, but the following one
    ** will attempt to compile the supplied statement against whatever subset
    ** of the schema was loaded before the error occurred. The primary
    ** purpose of this is to allow access to the sqlite_master table
    ** even when its contents have been corrupted.
    */
    DbSetProperty(db, iDb, DB_SchemaLoaded);
    rc = SQLITE_OK;
  }

  /* Jump here for an error that occurs after successfully allocating
  ** curMain and calling sqlite3BtreeEnter(). For an error that occurs
  ** before that point, jump to error_out.
  */
initone_error_out:
  sqlite3BtreeCloseCursor(curMain);
  sqlite3_free(curMain);
  sqlite3BtreeLeave(pDb->pBt);

error_out:
  if( rc==SQLITE_NOMEM || rc==SQLITE_IOERR_NOMEM ){
    db->mallocFailed = 1;
  }
  return rc;
}
Esempio n. 12
0
/*
** Process a pragma statement.  
**
** Pragmas are of this form:
**
**      PRAGMA [database.]id [= value]
**
** The identifier might also be a string.  The value is a string, and
** identifier, or a number.  If minusFlag is true, then the value is
** a number that was preceded by a minus sign.
**
** If the left side is "database.id" then pId1 is the database name
** and pId2 is the id.  If the left side is just "id" then pId1 is the
** id and pId2 is any empty string.
*/
void sqlite3Pragma(
  Parse *pParse, 
  Token *pId1,        /* First part of [database.]id field */
  Token *pId2,        /* Second part of [database.]id field, or NULL */
  Token *pValue,      /* Token for <value>, or NULL */
  int minusFlag       /* True if a '-' sign preceded <value> */
){
  char *zLeft = 0;       /* Nul-terminated UTF-8 string <id> */
  char *zRight = 0;      /* Nul-terminated UTF-8 string <value>, or NULL */
  const char *zDb = 0;   /* The database name */
  Token *pId;            /* Pointer to <id> token */
  int iDb;               /* Database index for <database> */
  sqlite3 *db = pParse->db;
  Db *pDb;
  Vdbe *v = sqlite3GetVdbe(pParse);
  if( v==0 ) return;

  /* Interpret the [database.] part of the pragma statement. iDb is the
  ** index of the database this pragma is being applied to in db.aDb[]. */
  iDb = sqlite3TwoPartName(pParse, pId1, pId2, &pId);
  if( iDb<0 ) return;
  pDb = &db->aDb[iDb];

  zLeft = sqlite3NameFromToken(pId);
  if( !zLeft ) return;
  if( minusFlag ){
    zRight = sqlite3MPrintf("-%T", pValue);
  }else{
    zRight = sqlite3NameFromToken(pValue);
  }

  zDb = ((iDb>0)?pDb->zName:0);
  if( sqlite3AuthCheck(pParse, SQLITE_PRAGMA, zLeft, zRight, zDb) ){
    goto pragma_out;
  }
 
  /*
  **  PRAGMA [database.]default_cache_size
  **  PRAGMA [database.]default_cache_size=N
  **
  ** The first form reports the current persistent setting for the
  ** page cache size.  The value returned is the maximum number of
  ** pages in the page cache.  The second form sets both the current
  ** page cache size value and the persistent page cache size value
  ** stored in the database file.
  **
  ** The default cache size is stored in meta-value 2 of page 1 of the
  ** database file.  The cache size is actually the absolute value of
  ** this memory location.  The sign of meta-value 2 determines the
  ** synchronous setting.  A negative value means synchronous is off
  ** and a positive value means synchronous is on.
  */
  if( sqlite3StrICmp(zLeft,"default_cache_size")==0 ){
    static const VdbeOpList getCacheSize[] = {
      { OP_ReadCookie,  0, 2,        0},  /* 0 */
      { OP_AbsValue,    0, 0,        0},
      { OP_Dup,         0, 0,        0},
      { OP_Integer,     0, 0,        0},
      { OP_Ne,          0, 6,        0},
      { OP_Integer,     0, 0,        0},  /* 5 */
      { OP_Callback,    1, 0,        0},
    };
    int addr;
    if( sqlite3ReadSchema(pParse) ) goto pragma_out;
    if( !zRight ){
      sqlite3VdbeSetNumCols(v, 1);
      sqlite3VdbeSetColName(v, 0, "cache_size", P3_STATIC);
      addr = sqlite3VdbeAddOpList(v, ArraySize(getCacheSize), getCacheSize);
      sqlite3VdbeChangeP1(v, addr, iDb);
      sqlite3VdbeChangeP1(v, addr+5, MAX_PAGES);
    }else{
      int size = atoi(zRight);
      if( size<0 ) size = -size;
      sqlite3BeginWriteOperation(pParse, 0, iDb);
      sqlite3VdbeAddOp(v, OP_Integer, size, 0);
      sqlite3VdbeAddOp(v, OP_ReadCookie, iDb, 2);
      addr = sqlite3VdbeAddOp(v, OP_Integer, 0, 0);
      sqlite3VdbeAddOp(v, OP_Ge, 0, addr+3);
      sqlite3VdbeAddOp(v, OP_Negative, 0, 0);
      sqlite3VdbeAddOp(v, OP_SetCookie, iDb, 2);
      pDb->cache_size = size;
      sqlite3BtreeSetCacheSize(pDb->pBt, pDb->cache_size);
    }
  }else

  /*
  **  PRAGMA [database.]page_size
  **  PRAGMA [database.]page_size=N
  **
  ** The first form reports the current setting for the
  ** database page size in bytes.  The second form sets the
  ** database page size value.  The value can only be set if
  ** the database has not yet been created.
  */
  if( sqlite3StrICmp(zLeft,"page_size")==0 ){
    Btree *pBt = pDb->pBt;
    if( !zRight ){
      int size = pBt ? sqlite3BtreeGetPageSize(pBt) : 0;
      returnSingleInt(pParse, "page_size", size);
    }else{
      sqlite3BtreeSetPageSize(pBt, atoi(zRight), sqlite3BtreeGetReserve(pBt));
    }
  }else

  /*
  **  PRAGMA [database.]cache_size
  **  PRAGMA [database.]cache_size=N
  **
  ** The first form reports the current local setting for the
  ** page cache size.  The local setting can be different from
  ** the persistent cache size value that is stored in the database
  ** file itself.  The value returned is the maximum number of
  ** pages in the page cache.  The second form sets the local
  ** page cache size value.  It does not change the persistent
  ** cache size stored on the disk so the cache size will revert
  ** to its default value when the database is closed and reopened.
  ** N should be a positive integer.
  */
  if( sqlite3StrICmp(zLeft,"cache_size")==0 ){
    if( sqlite3ReadSchema(pParse) ) goto pragma_out;
    if( !zRight ){
      returnSingleInt(pParse, "cache_size", pDb->cache_size);
    }else{
      int size = atoi(zRight);
      if( size<0 ) size = -size;
      pDb->cache_size = size;
      sqlite3BtreeSetCacheSize(pDb->pBt, pDb->cache_size);
    }
  }else

  /*
  **   PRAGMA temp_store
  **   PRAGMA temp_store = "default"|"memory"|"file"
  **
  ** Return or set the local value of the temp_store flag.  Changing
  ** the local value does not make changes to the disk file and the default
  ** value will be restored the next time the database is opened.
  **
  ** Note that it is possible for the library compile-time options to
  ** override this setting
  */
  if( sqlite3StrICmp(zLeft, "temp_store")==0 ){
    if( !zRight ){
      returnSingleInt(pParse, "temp_store", db->temp_store);
    }else{
      changeTempStorage(pParse, zRight);
    }
  }else

  /*
  **   PRAGMA [database.]synchronous
  **   PRAGMA [database.]synchronous=OFF|ON|NORMAL|FULL
  **
  ** Return or set the local value of the synchronous flag.  Changing
  ** the local value does not make changes to the disk file and the
  ** default value will be restored the next time the database is
  ** opened.
  */
  if( sqlite3StrICmp(zLeft,"synchronous")==0 ){
    if( sqlite3ReadSchema(pParse) ) goto pragma_out;
    if( !zRight ){
      returnSingleInt(pParse, "synchronous", pDb->safety_level-1);
    }else{
      if( !db->autoCommit ){
        sqlite3ErrorMsg(pParse, 
            "Safety level may not be changed inside a transaction");
      }else{
        pDb->safety_level = getSafetyLevel(zRight)+1;
        sqlite3BtreeSetSafetyLevel(pDb->pBt, pDb->safety_level);
      }
    }
  }else

#if 0  /* Used once during development.  No longer needed */
  if( sqlite3StrICmp(zLeft, "trigger_overhead_test")==0 ){
    if( getBoolean(zRight) ){
      sqlite3_always_code_trigger_setup = 1;
    }else{
      sqlite3_always_code_trigger_setup = 0;
    }
  }else
#endif

  if( flagPragma(pParse, zLeft, zRight) ){
    /* The flagPragma() subroutine also generates any necessary code
    ** there is nothing more to do here */
  }else

  /*
  **   PRAGMA table_info(<table>)
  **
  ** Return a single row for each column of the named table. The columns of
  ** the returned data set are:
  **
  ** cid:        Column id (numbered from left to right, starting at 0)
  ** name:       Column name
  ** type:       Column declaration type.
  ** notnull:    True if 'NOT NULL' is part of column declaration
  ** dflt_value: The default value for the column, if any.
  */
  if( sqlite3StrICmp(zLeft, "table_info")==0 && zRight ){
    Table *pTab;
    if( sqlite3ReadSchema(pParse) ) goto pragma_out;
    pTab = sqlite3FindTable(db, zRight, zDb);
    if( pTab ){
      int i;
      sqlite3VdbeSetNumCols(v, 6);
      sqlite3VdbeSetColName(v, 0, "cid", P3_STATIC);
      sqlite3VdbeSetColName(v, 1, "name", P3_STATIC);
      sqlite3VdbeSetColName(v, 2, "type", P3_STATIC);
      sqlite3VdbeSetColName(v, 3, "notnull", P3_STATIC);
      sqlite3VdbeSetColName(v, 4, "dflt_value", P3_STATIC);
      sqlite3VdbeSetColName(v, 5, "pk", P3_STATIC);
      sqlite3ViewGetColumnNames(pParse, pTab);
      for(i=0; i<pTab->nCol; i++){
        sqlite3VdbeAddOp(v, OP_Integer, i, 0);
        sqlite3VdbeOp3(v, OP_String8, 0, 0, pTab->aCol[i].zName, 0);
        sqlite3VdbeOp3(v, OP_String8, 0, 0,
           pTab->aCol[i].zType ? pTab->aCol[i].zType : "numeric", 0);
        sqlite3VdbeAddOp(v, OP_Integer, pTab->aCol[i].notNull, 0);
        sqlite3VdbeOp3(v, OP_String8, 0, 0,
           pTab->aCol[i].zDflt, P3_STATIC);
        sqlite3VdbeAddOp(v, OP_Integer, pTab->aCol[i].isPrimKey, 0);
        sqlite3VdbeAddOp(v, OP_Callback, 6, 0);
      }
    }
  }else

  if( sqlite3StrICmp(zLeft, "index_info")==0 && zRight ){
    Index *pIdx;
    Table *pTab;
    if( sqlite3ReadSchema(pParse) ) goto pragma_out;
    pIdx = sqlite3FindIndex(db, zRight, zDb);
    if( pIdx ){
      int i;
      pTab = pIdx->pTable;
      sqlite3VdbeSetNumCols(v, 3);
      sqlite3VdbeSetColName(v, 0, "seqno", P3_STATIC);
      sqlite3VdbeSetColName(v, 1, "cid", P3_STATIC);
      sqlite3VdbeSetColName(v, 2, "name", P3_STATIC);
      for(i=0; i<pIdx->nColumn; i++){
        int cnum = pIdx->aiColumn[i];
        sqlite3VdbeAddOp(v, OP_Integer, i, 0);
        sqlite3VdbeAddOp(v, OP_Integer, cnum, 0);
        assert( pTab->nCol>cnum );
        sqlite3VdbeOp3(v, OP_String8, 0, 0, pTab->aCol[cnum].zName, 0);
        sqlite3VdbeAddOp(v, OP_Callback, 3, 0);
      }
    }
  }else

  if( sqlite3StrICmp(zLeft, "index_list")==0 && zRight ){
    Index *pIdx;
    Table *pTab;
    if( sqlite3ReadSchema(pParse) ) goto pragma_out;
    pTab = sqlite3FindTable(db, zRight, zDb);
    if( pTab ){
      v = sqlite3GetVdbe(pParse);
      pIdx = pTab->pIndex;
      if( pIdx ){
        int i = 0; 
        sqlite3VdbeSetNumCols(v, 3);
        sqlite3VdbeSetColName(v, 0, "seq", P3_STATIC);
        sqlite3VdbeSetColName(v, 1, "name", P3_STATIC);
        sqlite3VdbeSetColName(v, 2, "unique", P3_STATIC);
        while(pIdx){
          sqlite3VdbeAddOp(v, OP_Integer, i, 0);
          sqlite3VdbeOp3(v, OP_String8, 0, 0, pIdx->zName, 0);
          sqlite3VdbeAddOp(v, OP_Integer, pIdx->onError!=OE_None, 0);
          sqlite3VdbeAddOp(v, OP_Callback, 3, 0);
          ++i;
          pIdx = pIdx->pNext;
        }
      }
    }
  }else

  if( sqlite3StrICmp(zLeft, "foreign_key_list")==0 && zRight ){
    FKey *pFK;
    Table *pTab;
    if( sqlite3ReadSchema(pParse) ) goto pragma_out;
    pTab = sqlite3FindTable(db, zRight, zDb);
    if( pTab ){
      v = sqlite3GetVdbe(pParse);
      pFK = pTab->pFKey;
      if( pFK ){
        int i = 0; 
        sqlite3VdbeSetNumCols(v, 5);
        sqlite3VdbeSetColName(v, 0, "id", P3_STATIC);
        sqlite3VdbeSetColName(v, 1, "seq", P3_STATIC);
        sqlite3VdbeSetColName(v, 2, "table", P3_STATIC);
        sqlite3VdbeSetColName(v, 3, "from", P3_STATIC);
        sqlite3VdbeSetColName(v, 4, "to", P3_STATIC);
        while(pFK){
          int j;
          for(j=0; j<pFK->nCol; j++){
            sqlite3VdbeAddOp(v, OP_Integer, i, 0);
            sqlite3VdbeAddOp(v, OP_Integer, j, 0);
            sqlite3VdbeOp3(v, OP_String8, 0, 0, pFK->zTo, 0);
            sqlite3VdbeOp3(v, OP_String8, 0, 0,
                             pTab->aCol[pFK->aCol[j].iFrom].zName, 0);
            sqlite3VdbeOp3(v, OP_String8, 0, 0, pFK->aCol[j].zCol, 0);
            sqlite3VdbeAddOp(v, OP_Callback, 5, 0);
          }
          ++i;
          pFK = pFK->pNextFrom;
        }
      }
    }
  }else

  if( sqlite3StrICmp(zLeft, "database_list")==0 ){
    int i;
    if( sqlite3ReadSchema(pParse) ) goto pragma_out;
    sqlite3VdbeSetNumCols(v, 3);
    sqlite3VdbeSetColName(v, 0, "seq", P3_STATIC);
    sqlite3VdbeSetColName(v, 1, "name", P3_STATIC);
    sqlite3VdbeSetColName(v, 2, "file", P3_STATIC);
    for(i=0; i<db->nDb; i++){
      if( db->aDb[i].pBt==0 ) continue;
      assert( db->aDb[i].zName!=0 );
      sqlite3VdbeAddOp(v, OP_Integer, i, 0);
      sqlite3VdbeOp3(v, OP_String8, 0, 0, db->aDb[i].zName, 0);
      sqlite3VdbeOp3(v, OP_String8, 0, 0,
           sqlite3BtreeGetFilename(db->aDb[i].pBt), 0);
      sqlite3VdbeAddOp(v, OP_Callback, 3, 0);
    }
  }else

#ifndef NDEBUG
  if( sqlite3StrICmp(zLeft, "parser_trace")==0 ){
    extern void sqlite3ParserTrace(FILE*, char *);
    if( getBoolean(zRight) ){
      sqlite3ParserTrace(stdout, "parser: ");
    }else{
      sqlite3ParserTrace(0, 0);
    }
  }else
#endif

  if( sqlite3StrICmp(zLeft, "integrity_check")==0 ){
    int i, j, addr;

    /* Code that initializes the integrity check program.  Set the
    ** error count 0
    */
    static const VdbeOpList initCode[] = {
      { OP_Integer,     0, 0,        0},
      { OP_MemStore,    0, 1,        0},
    };

    /* Code that appears at the end of the integrity check.  If no error
    ** messages have been generated, output OK.  Otherwise output the
    ** error message
    */
    static const VdbeOpList endCode[] = {
      { OP_MemLoad,     0, 0,        0},
      { OP_Integer,     0, 0,        0},
      { OP_Ne,          0, 0,        0},    /* 2 */
      { OP_String8,     0, 0,        "ok"},
      { OP_Callback,    1, 0,        0},
    };

    /* Initialize the VDBE program */
    if( sqlite3ReadSchema(pParse) ) goto pragma_out;
    sqlite3VdbeSetNumCols(v, 1);
    sqlite3VdbeSetColName(v, 0, "integrity_check", P3_STATIC);
    sqlite3VdbeAddOpList(v, ArraySize(initCode), initCode);

    /* Do an integrity check on each database file */
    for(i=0; i<db->nDb; i++){
      HashElem *x;
      int cnt = 0;

      sqlite3CodeVerifySchema(pParse, i);

      /* Do an integrity check of the B-Tree
      */
      for(x=sqliteHashFirst(&db->aDb[i].tblHash); x; x=sqliteHashNext(x)){
        Table *pTab = sqliteHashData(x);
        Index *pIdx;
        sqlite3VdbeAddOp(v, OP_Integer, pTab->tnum, 0);
        cnt++;
        for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
          if( sqlite3CheckIndexCollSeq(pParse, pIdx) ) goto pragma_out;
          sqlite3VdbeAddOp(v, OP_Integer, pIdx->tnum, 0);
          cnt++;
        }
      }
      assert( cnt>0 );
      sqlite3VdbeAddOp(v, OP_IntegrityCk, cnt, i);
      sqlite3VdbeAddOp(v, OP_Dup, 0, 1);
      addr = sqlite3VdbeOp3(v, OP_String8, 0, 0, "ok", P3_STATIC);
      sqlite3VdbeAddOp(v, OP_Eq, 0, addr+6);
      sqlite3VdbeOp3(v, OP_String8, 0, 0,
         sqlite3MPrintf("*** in database %s ***\n", db->aDb[i].zName),
         P3_DYNAMIC);
      sqlite3VdbeAddOp(v, OP_Pull, 1, 0);
      sqlite3VdbeAddOp(v, OP_Concat, 0, 1);
      sqlite3VdbeAddOp(v, OP_Callback, 1, 0);

      /* Make sure all the indices are constructed correctly.
      */
      sqlite3CodeVerifySchema(pParse, i);
      for(x=sqliteHashFirst(&db->aDb[i].tblHash); x; x=sqliteHashNext(x)){
        Table *pTab = sqliteHashData(x);
        Index *pIdx;
        int loopTop;

        if( pTab->pIndex==0 ) continue;
        sqlite3OpenTableAndIndices(pParse, pTab, 1, OP_OpenRead);
        sqlite3VdbeAddOp(v, OP_Integer, 0, 0);
        sqlite3VdbeAddOp(v, OP_MemStore, 1, 1);
        loopTop = sqlite3VdbeAddOp(v, OP_Rewind, 1, 0);
        sqlite3VdbeAddOp(v, OP_MemIncr, 1, 0);
        for(j=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, j++){
          int jmp2;
          static const VdbeOpList idxErr[] = {
            { OP_MemIncr,     0,  0,  0},
            { OP_String8,     0,  0,  "rowid "},
            { OP_Recno,       1,  0,  0},
            { OP_String8,     0,  0,  " missing from index "},
            { OP_String8,     0,  0,  0},    /* 4 */
            { OP_Concat,      2,  0,  0},
            { OP_Callback,    1,  0,  0},
          };
          sqlite3GenerateIndexKey(v, pIdx, 1);
          jmp2 = sqlite3VdbeAddOp(v, OP_Found, j+2, 0);
          addr = sqlite3VdbeAddOpList(v, ArraySize(idxErr), idxErr);
          sqlite3VdbeChangeP3(v, addr+4, pIdx->zName, P3_STATIC);
          sqlite3VdbeChangeP2(v, jmp2, sqlite3VdbeCurrentAddr(v));
        }
        sqlite3VdbeAddOp(v, OP_Next, 1, loopTop+1);
        sqlite3VdbeChangeP2(v, loopTop, sqlite3VdbeCurrentAddr(v));
        for(j=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, j++){
          static const VdbeOpList cntIdx[] = {
             { OP_Integer,      0,  0,  0},
             { OP_MemStore,     2,  1,  0},
             { OP_Rewind,       0,  0,  0},  /* 2 */
             { OP_MemIncr,      2,  0,  0},
             { OP_Next,         0,  0,  0},  /* 4 */
             { OP_MemLoad,      1,  0,  0},
             { OP_MemLoad,      2,  0,  0},
             { OP_Eq,           0,  0,  0},  /* 7 */
             { OP_MemIncr,      0,  0,  0},
             { OP_String8,      0,  0,  "wrong # of entries in index "},
             { OP_String8,      0,  0,  0},  /* 10 */
             { OP_Concat,       0,  0,  0},
             { OP_Callback,     1,  0,  0},
          };
          if( pIdx->tnum==0 ) continue;
          addr = sqlite3VdbeAddOpList(v, ArraySize(cntIdx), cntIdx);
          sqlite3VdbeChangeP1(v, addr+2, j+2);
          sqlite3VdbeChangeP2(v, addr+2, addr+5);
          sqlite3VdbeChangeP1(v, addr+4, j+2);
          sqlite3VdbeChangeP2(v, addr+4, addr+3);
          sqlite3VdbeChangeP2(v, addr+7, addr+ArraySize(cntIdx));
          sqlite3VdbeChangeP3(v, addr+10, pIdx->zName, P3_STATIC);
        }
      } 
    }
    addr = sqlite3VdbeAddOpList(v, ArraySize(endCode), endCode);
    sqlite3VdbeChangeP2(v, addr+2, addr+ArraySize(endCode));
  }else
  /*
  **   PRAGMA encoding
  **   PRAGMA encoding = "utf-8"|"utf-16"|"utf-16le"|"utf-16be"
  **
  ** In it's first form, this pragma returns the encoding of the main
  ** database. If the database is not initialized, it is initialized now.
  **
  ** The second form of this pragma is a no-op if the main database file
  ** has not already been initialized. In this case it sets the default
  ** encoding that will be used for the main database file if a new file
  ** is created. If an existing main database file is opened, then the
  ** default text encoding for the existing database is used.
  ** 
  ** In all cases new databases created using the ATTACH command are
  ** created to use the same default text encoding as the main database. If
  ** the main database has not been initialized and/or created when ATTACH
  ** is executed, this is done before the ATTACH operation.
  **
  ** In the second form this pragma sets the text encoding to be used in
  ** new database files created using this database handle. It is only
  ** useful if invoked immediately after the main database i
  */
  if( sqlite3StrICmp(zLeft, "encoding")==0 ){
    static struct EncName {
      char *zName;
      u8 enc;
    } encnames[] = {
      { "UTF-8",    SQLITE_UTF8        },
      { "UTF8",     SQLITE_UTF8        },
      { "UTF-16le", SQLITE_UTF16LE     },
      { "UTF16le",  SQLITE_UTF16LE     },
      { "UTF-16be", SQLITE_UTF16BE     },
      { "UTF16be",  SQLITE_UTF16BE     },
      { "UTF-16",   0 /* Filled in at run-time */ },
      { "UTF16",    0 /* Filled in at run-time */ },
      { 0, 0 }
    };
    struct EncName *pEnc;
    encnames[6].enc = encnames[7].enc = SQLITE_UTF16NATIVE;
    if( !zRight ){    /* "PRAGMA encoding" */
      if( sqlite3ReadSchema(pParse) ) goto pragma_out;
      sqlite3VdbeSetNumCols(v, 1);
      sqlite3VdbeSetColName(v, 0, "encoding", P3_STATIC);
      sqlite3VdbeAddOp(v, OP_String8, 0, 0);
      for(pEnc=&encnames[0]; pEnc->zName; pEnc++){
        if( pEnc->enc==pParse->db->enc ){
          sqlite3VdbeChangeP3(v, -1, pEnc->zName, P3_STATIC);
          break;
        }
      }
      sqlite3VdbeAddOp(v, OP_Callback, 1, 0);
    }else{                        /* "PRAGMA encoding = XXX" */
      /* Only change the value of sqlite.enc if the database handle is not
      ** initialized. If the main database exists, the new sqlite.enc value
      ** will be overwritten when the schema is next loaded. If it does not
      ** already exists, it will be created to use the new encoding value.
      */
      if( !(pParse->db->flags&SQLITE_Initialized) ){
        for(pEnc=&encnames[0]; pEnc->zName; pEnc++){
          if( 0==sqlite3StrICmp(zRight, pEnc->zName) ){
            pParse->db->enc = pEnc->enc;
            break;
          }
        }
        if( !pEnc->zName ){
          sqlite3ErrorMsg(pParse, "unsupported encoding: %s", zRight);
        }
      }
    }
  }else

#if defined(SQLITE_DEBUG) || defined(SQLITE_TEST)
  /*
  ** Report the current state of file logs for all databases
  */
  if( sqlite3StrICmp(zLeft, "lock_status")==0 ){
    static const char *const azLockName[] = {
      "unlocked", "shared", "reserved", "pending", "exclusive"
    };
    int i;
    Vdbe *v = sqlite3GetVdbe(pParse);
    sqlite3VdbeSetNumCols(v, 2);
    sqlite3VdbeSetColName(v, 0, "database", P3_STATIC);
    sqlite3VdbeSetColName(v, 1, "status", P3_STATIC);
    for(i=0; i<db->nDb; i++){
      Btree *pBt;
      Pager *pPager;
      if( db->aDb[i].zName==0 ) continue;
      sqlite3VdbeOp3(v, OP_String, 0, 0, db->aDb[i].zName, P3_STATIC);
      pBt = db->aDb[i].pBt;
      if( pBt==0 || (pPager = sqlite3BtreePager(pBt))==0 ){
        sqlite3VdbeOp3(v, OP_String, 0, 0, "closed", P3_STATIC);
      }else{
        int j = sqlite3pager_lockstate(pPager);
        sqlite3VdbeOp3(v, OP_String, 0, 0, 
            (j>=0 && j<=4) ? azLockName[j] : "unknown", P3_STATIC);
      }
      sqlite3VdbeAddOp(v, OP_Callback, 2, 0);
    }
  }else
#endif

  {}
pragma_out:
  sqliteFree(zLeft);
  sqliteFree(zRight);
}
Esempio n. 13
0
/*
** Process a pragma statement.  
**
** Pragmas are of this form:
**
**      PRAGMA [database.]id [= value]
**
** The identifier might also be a string.  The value is a string, and
** identifier, or a number.  If minusFlag is true, then the value is
** a number that was preceded by a minus sign.
**
** If the left side is "database.id" then pId1 is the database name
** and pId2 is the id.  If the left side is just "id" then pId1 is the
** id and pId2 is any empty string.
*/
void sqlite3Pragma(
  Parse *pParse, 
  Token *pId1,        /* First part of [database.]id field */
  Token *pId2,        /* Second part of [database.]id field, or NULL */
  Token *pValue,      /* Token for <value>, or NULL */
  int minusFlag       /* True if a '-' sign preceded <value> */
){
  char *zLeft = 0;       /* Nul-terminated UTF-8 string <id> */
  char *zRight = 0;      /* Nul-terminated UTF-8 string <value>, or NULL */
  const char *zDb = 0;   /* The database name */
  Token *pId;            /* Pointer to <id> token */
  int iDb;               /* Database index for <database> */
  sqlite3 *db = pParse->db;
  Db *pDb;
  Vdbe *v = pParse->pVdbe = sqlite3VdbeCreate(db);
  if( v==0 ) return;
  pParse->nMem = 2;

  /* Interpret the [database.] part of the pragma statement. iDb is the
  ** index of the database this pragma is being applied to in db.aDb[]. */
  iDb = sqlite3TwoPartName(pParse, pId1, pId2, &pId);
  if( iDb<0 ) return;
  pDb = &db->aDb[iDb];

  /* If the temp database has been explicitly named as part of the 
  ** pragma, make sure it is open. 
  */
  if( iDb==1 && sqlite3OpenTempDatabase(pParse) ){
    return;
  }

  zLeft = sqlite3NameFromToken(db, pId);
  if( !zLeft ) return;
  if( minusFlag ){
    zRight = sqlite3MPrintf(db, "-%T", pValue);
  }else{
    zRight = sqlite3NameFromToken(db, pValue);
  }

  zDb = ((pId2 && pId2->n>0)?pDb->zName:0);
  if( sqlite3AuthCheck(pParse, SQLITE_PRAGMA, zLeft, zRight, zDb) ){
    goto pragma_out;
  }
 
#ifndef SQLITE_OMIT_PAGER_PRAGMAS
  /*
  **  PRAGMA [database.]default_cache_size
  **  PRAGMA [database.]default_cache_size=N
  **
  ** The first form reports the current persistent setting for the
  ** page cache size.  The value returned is the maximum number of
  ** pages in the page cache.  The second form sets both the current
  ** page cache size value and the persistent page cache size value
  ** stored in the database file.
  **
  ** The default cache size is stored in meta-value 2 of page 1 of the
  ** database file.  The cache size is actually the absolute value of
  ** this memory location.  The sign of meta-value 2 determines the
  ** synchronous setting.  A negative value means synchronous is off
  ** and a positive value means synchronous is on.
  */
  if( sqlite3StrICmp(zLeft,"default_cache_size")==0 ){
    static const VdbeOpList getCacheSize[] = {
      { OP_ReadCookie,  0, 1,        2},  /* 0 */
      { OP_IfPos,       1, 6,        0},
      { OP_Integer,     0, 2,        0},
      { OP_Subtract,    1, 2,        1},
      { OP_IfPos,       1, 6,        0},
      { OP_Integer,     0, 1,        0},  /* 5 */
      { OP_ResultRow,   1, 1,        0},
    };
    int addr;
    if( sqlite3ReadSchema(pParse) ) goto pragma_out;
    sqlite3VdbeUsesBtree(v, iDb);
    if( !zRight ){
      sqlite3VdbeSetNumCols(v, 1);
      sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "cache_size", P4_STATIC);
      pParse->nMem += 2;
      addr = sqlite3VdbeAddOpList(v, ArraySize(getCacheSize), getCacheSize);
      sqlite3VdbeChangeP1(v, addr, iDb);
      sqlite3VdbeChangeP1(v, addr+5, SQLITE_DEFAULT_CACHE_SIZE);
    }else{
      int size = atoi(zRight);
      if( size<0 ) size = -size;
      sqlite3BeginWriteOperation(pParse, 0, iDb);
      sqlite3VdbeAddOp2(v, OP_Integer, size, 1);
      sqlite3VdbeAddOp3(v, OP_ReadCookie, iDb, 2, 2);
      addr = sqlite3VdbeAddOp2(v, OP_IfPos, 2, 0);
      sqlite3VdbeAddOp2(v, OP_Integer, -size, 1);
      sqlite3VdbeJumpHere(v, addr);
      sqlite3VdbeAddOp3(v, OP_SetCookie, iDb, 2, 1);
      pDb->pSchema->cache_size = size;
      sqlite3BtreeSetCacheSize(pDb->pBt, pDb->pSchema->cache_size);
    }
  }else

  /*
  **  PRAGMA [database.]page_size
  **  PRAGMA [database.]page_size=N
  **
  ** The first form reports the current setting for the
  ** database page size in bytes.  The second form sets the
  ** database page size value.  The value can only be set if
  ** the database has not yet been created.
  */
  if( sqlite3StrICmp(zLeft,"page_size")==0 ){
    Btree *pBt = pDb->pBt;
    if( !zRight ){
      int size = pBt ? sqlite3BtreeGetPageSize(pBt) : 0;
      returnSingleInt(pParse, "page_size", size);
    }else{
      /* Malloc may fail when setting the page-size, as there is an internal
      ** buffer that the pager module resizes using sqlite3_realloc().
      */
      db->nextPagesize = atoi(zRight);
      if( SQLITE_NOMEM==sqlite3BtreeSetPageSize(pBt, db->nextPagesize, -1) ){
        db->mallocFailed = 1;
      }
    }
  }else

  /*
  **  PRAGMA [database.]max_page_count
  **  PRAGMA [database.]max_page_count=N
  **
  ** The first form reports the current setting for the
  ** maximum number of pages in the database file.  The 
  ** second form attempts to change this setting.  Both
  ** forms return the current setting.
  */
  if( sqlite3StrICmp(zLeft,"max_page_count")==0 ){
    Btree *pBt = pDb->pBt;
    int newMax = 0;
    if( zRight ){
      newMax = atoi(zRight);
    }
    if( pBt ){
      newMax = sqlite3BtreeMaxPageCount(pBt, newMax);
    }
    returnSingleInt(pParse, "max_page_count", newMax);
  }else

  /*
  **  PRAGMA [database.]page_count
  **
  ** Return the number of pages in the specified database.
  */
  if( sqlite3StrICmp(zLeft,"page_count")==0 ){
    Vdbe *v;
    int iReg;
    v = sqlite3GetVdbe(pParse);
    if( !v || sqlite3ReadSchema(pParse) ) goto pragma_out;
    sqlite3CodeVerifySchema(pParse, iDb);
    iReg = ++pParse->nMem;
    sqlite3VdbeAddOp2(v, OP_Pagecount, iDb, iReg);
    sqlite3VdbeAddOp2(v, OP_ResultRow, iReg, 1);
    sqlite3VdbeSetNumCols(v, 1);
    sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "page_count", P4_STATIC);
  }else

  /*
  **  PRAGMA [database.]locking_mode
  **  PRAGMA [database.]locking_mode = (normal|exclusive)
  */
  if( sqlite3StrICmp(zLeft,"locking_mode")==0 ){
    const char *zRet = "normal";
    int eMode = getLockingMode(zRight);

    if( pId2->n==0 && eMode==PAGER_LOCKINGMODE_QUERY ){
      /* Simple "PRAGMA locking_mode;" statement. This is a query for
      ** the current default locking mode (which may be different to
      ** the locking-mode of the main database).
      */
      eMode = db->dfltLockMode;
    }else{
      Pager *pPager;
      if( pId2->n==0 ){
        /* This indicates that no database name was specified as part
        ** of the PRAGMA command. In this case the locking-mode must be
        ** set on all attached databases, as well as the main db file.
        **
        ** Also, the sqlite3.dfltLockMode variable is set so that
        ** any subsequently attached databases also use the specified
        ** locking mode.
        */
        int ii;
        assert(pDb==&db->aDb[0]);
        for(ii=2; ii<db->nDb; ii++){
          pPager = sqlite3BtreePager(db->aDb[ii].pBt);
          sqlite3PagerLockingMode(pPager, eMode);
        }
        db->dfltLockMode = eMode;
      }
      pPager = sqlite3BtreePager(pDb->pBt);
      eMode = sqlite3PagerLockingMode(pPager, eMode);
    }

    assert(eMode==PAGER_LOCKINGMODE_NORMAL||eMode==PAGER_LOCKINGMODE_EXCLUSIVE);
    if( eMode==PAGER_LOCKINGMODE_EXCLUSIVE ){
      zRet = "exclusive";
    }
    sqlite3VdbeSetNumCols(v, 1);
    sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "locking_mode", P4_STATIC);
    sqlite3VdbeAddOp4(v, OP_String8, 0, 1, 0, zRet, 0);
    sqlite3VdbeAddOp2(v, OP_ResultRow, 1, 1);
  }else

  /*
  **  PRAGMA [database.]journal_mode
  **  PRAGMA [database.]journal_mode = (delete|persist|off)
  */
  if( sqlite3StrICmp(zLeft,"journal_mode")==0 ){
    int eMode;
    static char * const azModeName[] = {"delete", "persist", "off", "truncate"};

    if( zRight==0 ){
      eMode = PAGER_JOURNALMODE_QUERY;
    }else{
      int n = strlen(zRight);
      eMode = sizeof(azModeName)/sizeof(azModeName[0]) - 1;
      while( eMode>=0 && sqlite3StrNICmp(zRight, azModeName[eMode], n)!=0 ){
        eMode--;
      }
    }
    if( pId2->n==0 && eMode==PAGER_JOURNALMODE_QUERY ){
      /* Simple "PRAGMA journal_mode;" statement. This is a query for
      ** the current default journal mode (which may be different to
      ** the journal-mode of the main database).
      */
      eMode = db->dfltJournalMode;
    }else{
      Pager *pPager;
      if( pId2->n==0 ){
        /* This indicates that no database name was specified as part
        ** of the PRAGMA command. In this case the journal-mode must be
        ** set on all attached databases, as well as the main db file.
        **
        ** Also, the sqlite3.dfltJournalMode variable is set so that
        ** any subsequently attached databases also use the specified
        ** journal mode.
        */
        int ii;
        assert(pDb==&db->aDb[0]);
        for(ii=1; ii<db->nDb; ii++){
          if( db->aDb[ii].pBt ){
            pPager = sqlite3BtreePager(db->aDb[ii].pBt);
            sqlite3PagerJournalMode(pPager, eMode);
          }
        }
        db->dfltJournalMode = eMode;
      }
      pPager = sqlite3BtreePager(pDb->pBt);
      eMode = sqlite3PagerJournalMode(pPager, eMode);
    }
    assert( eMode==PAGER_JOURNALMODE_DELETE
              || eMode==PAGER_JOURNALMODE_TRUNCATE
              || eMode==PAGER_JOURNALMODE_PERSIST
              || eMode==PAGER_JOURNALMODE_OFF );
    sqlite3VdbeSetNumCols(v, 1);
    sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "journal_mode", P4_STATIC);
    sqlite3VdbeAddOp4(v, OP_String8, 0, 1, 0, 
           azModeName[eMode], P4_STATIC);
    sqlite3VdbeAddOp2(v, OP_ResultRow, 1, 1);
  }else

  /*
  **  PRAGMA [database.]journal_size_limit
  **  PRAGMA [database.]journal_size_limit=N
  **
  ** Get or set the (boolean) value of the database 'auto-vacuum' parameter.
  */
  if( sqlite3StrICmp(zLeft,"journal_size_limit")==0 ){
    Pager *pPager = sqlite3BtreePager(pDb->pBt);
    i64 iLimit = -2;
    if( zRight ){
      int iLimit32 = atoi(zRight);
      if( iLimit32<-1 ){
        iLimit32 = -1;
      }
      iLimit = iLimit32;
    }
    iLimit = sqlite3PagerJournalSizeLimit(pPager, iLimit);
    returnSingleInt(pParse, "journal_size_limit", (int)iLimit);
  }else

#endif /* SQLITE_OMIT_PAGER_PRAGMAS */

  /*
  **  PRAGMA [database.]auto_vacuum
  **  PRAGMA [database.]auto_vacuum=N
  **
  ** Get or set the (boolean) value of the database 'auto-vacuum' parameter.
  */
#ifndef SQLITE_OMIT_AUTOVACUUM
  if( sqlite3StrICmp(zLeft,"auto_vacuum")==0 ){
    Btree *pBt = pDb->pBt;
    if( sqlite3ReadSchema(pParse) ){
      goto pragma_out;
    }
    if( !zRight ){
      int auto_vacuum = 
          pBt ? sqlite3BtreeGetAutoVacuum(pBt) : SQLITE_DEFAULT_AUTOVACUUM;
      returnSingleInt(pParse, "auto_vacuum", auto_vacuum);
    }else{
      int eAuto = getAutoVacuum(zRight);
      db->nextAutovac = eAuto;
      if( eAuto>=0 ){
        /* Call SetAutoVacuum() to set initialize the internal auto and
        ** incr-vacuum flags. This is required in case this connection
        ** creates the database file. It is important that it is created
        ** as an auto-vacuum capable db.
        */
        int rc = sqlite3BtreeSetAutoVacuum(pBt, eAuto);
        if( rc==SQLITE_OK && (eAuto==1 || eAuto==2) ){
          /* When setting the auto_vacuum mode to either "full" or 
          ** "incremental", write the value of meta[6] in the database
          ** file. Before writing to meta[6], check that meta[3] indicates
          ** that this really is an auto-vacuum capable database.
          */
          static const VdbeOpList setMeta6[] = {
            { OP_Transaction,    0,               1,        0},    /* 0 */
            { OP_ReadCookie,     0,               1,        3},    /* 1 */
            { OP_If,             1,               0,        0},    /* 2 */
            { OP_Halt,           SQLITE_OK,       OE_Abort, 0},    /* 3 */
            { OP_Integer,        0,               1,        0},    /* 4 */
            { OP_SetCookie,      0,               6,        1},    /* 5 */
          };
          int iAddr;
          iAddr = sqlite3VdbeAddOpList(v, ArraySize(setMeta6), setMeta6);
          sqlite3VdbeChangeP1(v, iAddr, iDb);
          sqlite3VdbeChangeP1(v, iAddr+1, iDb);
          sqlite3VdbeChangeP2(v, iAddr+2, iAddr+4);
          sqlite3VdbeChangeP1(v, iAddr+4, eAuto-1);
          sqlite3VdbeChangeP1(v, iAddr+5, iDb);
          sqlite3VdbeUsesBtree(v, iDb);
        }
      }
    }
  }else
#endif

  /*
  **  PRAGMA [database.]incremental_vacuum(N)
  **
  ** Do N steps of incremental vacuuming on a database.
  */
#ifndef SQLITE_OMIT_AUTOVACUUM
  if( sqlite3StrICmp(zLeft,"incremental_vacuum")==0 ){
    int iLimit, addr;
    if( sqlite3ReadSchema(pParse) ){
      goto pragma_out;
    }
    if( zRight==0 || !sqlite3GetInt32(zRight, &iLimit) || iLimit<=0 ){
      iLimit = 0x7fffffff;
    }
    sqlite3BeginWriteOperation(pParse, 0, iDb);
    sqlite3VdbeAddOp2(v, OP_Integer, iLimit, 1);
    addr = sqlite3VdbeAddOp1(v, OP_IncrVacuum, iDb);
    sqlite3VdbeAddOp1(v, OP_ResultRow, 1);
    sqlite3VdbeAddOp2(v, OP_AddImm, 1, -1);
    sqlite3VdbeAddOp2(v, OP_IfPos, 1, addr);
    sqlite3VdbeJumpHere(v, addr);
  }else
#endif

#ifndef SQLITE_OMIT_PAGER_PRAGMAS
  /*
  **  PRAGMA [database.]cache_size
  **  PRAGMA [database.]cache_size=N
  **
  ** The first form reports the current local setting for the
  ** page cache size.  The local setting can be different from
  ** the persistent cache size value that is stored in the database
  ** file itself.  The value returned is the maximum number of
  ** pages in the page cache.  The second form sets the local
  ** page cache size value.  It does not change the persistent
  ** cache size stored on the disk so the cache size will revert
  ** to its default value when the database is closed and reopened.
  ** N should be a positive integer.
  */
  if( sqlite3StrICmp(zLeft,"cache_size")==0 ){
    if( sqlite3ReadSchema(pParse) ) goto pragma_out;
    if( !zRight ){
      returnSingleInt(pParse, "cache_size", pDb->pSchema->cache_size);
    }else{
      int size = atoi(zRight);
      if( size<0 ) size = -size;
      pDb->pSchema->cache_size = size;
      sqlite3BtreeSetCacheSize(pDb->pBt, pDb->pSchema->cache_size);
    }
  }else

  /*
  **   PRAGMA temp_store
  **   PRAGMA temp_store = "default"|"memory"|"file"
  **
  ** Return or set the local value of the temp_store flag.  Changing
  ** the local value does not make changes to the disk file and the default
  ** value will be restored the next time the database is opened.
  **
  ** Note that it is possible for the library compile-time options to
  ** override this setting
  */
  if( sqlite3StrICmp(zLeft, "temp_store")==0 ){
    if( !zRight ){
      returnSingleInt(pParse, "temp_store", db->temp_store);
    }else{
      changeTempStorage(pParse, zRight);
    }
  }else

  /*
  **   PRAGMA temp_store_directory
  **   PRAGMA temp_store_directory = ""|"directory_name"
  **
  ** Return or set the local value of the temp_store_directory flag.  Changing
  ** the value sets a specific directory to be used for temporary files.
  ** Setting to a null string reverts to the default temporary directory search.
  ** If temporary directory is changed, then invalidateTempStorage.
  **
  */
  if( sqlite3StrICmp(zLeft, "temp_store_directory")==0 ){
    if( !zRight ){
      if( sqlite3_temp_directory ){
        sqlite3VdbeSetNumCols(v, 1);
        sqlite3VdbeSetColName(v, 0, COLNAME_NAME, 
            "temp_store_directory", P4_STATIC);
        sqlite3VdbeAddOp4(v, OP_String8, 0, 1, 0, sqlite3_temp_directory, 0);
        sqlite3VdbeAddOp2(v, OP_ResultRow, 1, 1);
      }
    }else{
#ifndef SQLITE_OMIT_WSD
      if( zRight[0] ){
        int rc;
        int res;
        rc = sqlite3OsAccess(db->pVfs, zRight, SQLITE_ACCESS_READWRITE, &res);
        if( rc!=SQLITE_OK || res==0 ){
          sqlite3ErrorMsg(pParse, "not a writable directory");
          goto pragma_out;
        }
      }
      if( SQLITE_TEMP_STORE==0
       || (SQLITE_TEMP_STORE==1 && db->temp_store<=1)
       || (SQLITE_TEMP_STORE==2 && db->temp_store==1)
      ){
        invalidateTempStorage(pParse);
      }
      sqlite3_free(sqlite3_temp_directory);
      if( zRight[0] ){
        sqlite3_temp_directory = sqlite3DbStrDup(0, zRight);
      }else{
        sqlite3_temp_directory = 0;
      }
#endif /* SQLITE_OMIT_WSD */
    }
  }else

  /*
  **   PRAGMA [database.]synchronous
  **   PRAGMA [database.]synchronous=OFF|ON|NORMAL|FULL
  **
  ** Return or set the local value of the synchronous flag.  Changing
  ** the local value does not make changes to the disk file and the
  ** default value will be restored the next time the database is
  ** opened.
  */
  if( sqlite3StrICmp(zLeft,"synchronous")==0 ){
    if( sqlite3ReadSchema(pParse) ) goto pragma_out;
    if( !zRight ){
      returnSingleInt(pParse, "synchronous", pDb->safety_level-1);
    }else{
      if( !db->autoCommit ){
        sqlite3ErrorMsg(pParse, 
            "Safety level may not be changed inside a transaction");
      }else{
        pDb->safety_level = getSafetyLevel(zRight)+1;
      }
    }
  }else
#endif /* SQLITE_OMIT_PAGER_PRAGMAS */

#ifndef SQLITE_OMIT_FLAG_PRAGMAS
  if( flagPragma(pParse, zLeft, zRight) ){
    /* The flagPragma() subroutine also generates any necessary code
    ** there is nothing more to do here */
  }else
#endif /* SQLITE_OMIT_FLAG_PRAGMAS */

#ifndef SQLITE_OMIT_SCHEMA_PRAGMAS
  /*
  **   PRAGMA table_info(<table>)
  **
  ** Return a single row for each column of the named table. The columns of
  ** the returned data set are:
  **
  ** cid:        Column id (numbered from left to right, starting at 0)
  ** name:       Column name
  ** type:       Column declaration type.
  ** notnull:    True if 'NOT NULL' is part of column declaration
  ** dflt_value: The default value for the column, if any.
  */
  if( sqlite3StrICmp(zLeft, "table_info")==0 && zRight ){
    Table *pTab;
    if( sqlite3ReadSchema(pParse) ) goto pragma_out;
    pTab = sqlite3FindTable(db, zRight, zDb);
    if( pTab ){
      int i;
      int nHidden = 0;
      Column *pCol;
      sqlite3VdbeSetNumCols(v, 6);
      pParse->nMem = 6;
      sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "cid", P4_STATIC);
      sqlite3VdbeSetColName(v, 1, COLNAME_NAME, "name", P4_STATIC);
      sqlite3VdbeSetColName(v, 2, COLNAME_NAME, "type", P4_STATIC);
      sqlite3VdbeSetColName(v, 3, COLNAME_NAME, "notnull", P4_STATIC);
      sqlite3VdbeSetColName(v, 4, COLNAME_NAME, "dflt_value", P4_STATIC);
      sqlite3VdbeSetColName(v, 5, COLNAME_NAME, "pk", P4_STATIC);
      sqlite3ViewGetColumnNames(pParse, pTab);
      for(i=0, pCol=pTab->aCol; i<pTab->nCol; i++, pCol++){
        const Token *pDflt;
        if( IsHiddenColumn(pCol) ){
          nHidden++;
          continue;
        }
        sqlite3VdbeAddOp2(v, OP_Integer, i-nHidden, 1);
        sqlite3VdbeAddOp4(v, OP_String8, 0, 2, 0, pCol->zName, 0);
        sqlite3VdbeAddOp4(v, OP_String8, 0, 3, 0,
           pCol->zType ? pCol->zType : "", 0);
        sqlite3VdbeAddOp2(v, OP_Integer, pCol->notNull, 4);
        if( pCol->pDflt && (pDflt = &pCol->pDflt->span)->z ){
          sqlite3VdbeAddOp4(v, OP_String8, 0, 5, 0, (char*)pDflt->z, pDflt->n);
        }else{
          sqlite3VdbeAddOp2(v, OP_Null, 0, 5);
        }
        sqlite3VdbeAddOp2(v, OP_Integer, pCol->isPrimKey, 6);
        sqlite3VdbeAddOp2(v, OP_ResultRow, 1, 6);
      }
    }
  }else

  if( sqlite3StrICmp(zLeft, "index_info")==0 && zRight ){
    Index *pIdx;
    Table *pTab;
    if( sqlite3ReadSchema(pParse) ) goto pragma_out;
    pIdx = sqlite3FindIndex(db, zRight, zDb);
    if( pIdx ){
      int i;
      pTab = pIdx->pTable;
      sqlite3VdbeSetNumCols(v, 3);
      pParse->nMem = 3;
      sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "seqno", P4_STATIC);
      sqlite3VdbeSetColName(v, 1, COLNAME_NAME, "cid", P4_STATIC);
      sqlite3VdbeSetColName(v, 2, COLNAME_NAME, "name", P4_STATIC);
      for(i=0; i<pIdx->nColumn; i++){
        int cnum = pIdx->aiColumn[i];
        sqlite3VdbeAddOp2(v, OP_Integer, i, 1);
        sqlite3VdbeAddOp2(v, OP_Integer, cnum, 2);
        assert( pTab->nCol>cnum );
        sqlite3VdbeAddOp4(v, OP_String8, 0, 3, 0, pTab->aCol[cnum].zName, 0);
        sqlite3VdbeAddOp2(v, OP_ResultRow, 1, 3);
      }
    }
  }else

  if( sqlite3StrICmp(zLeft, "index_list")==0 && zRight ){
    Index *pIdx;
    Table *pTab;
    if( sqlite3ReadSchema(pParse) ) goto pragma_out;
    pTab = sqlite3FindTable(db, zRight, zDb);
    if( pTab ){
      v = sqlite3GetVdbe(pParse);
      pIdx = pTab->pIndex;
      if( pIdx ){
        int i = 0; 
        sqlite3VdbeSetNumCols(v, 3);
        pParse->nMem = 3;
        sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "seq", P4_STATIC);
        sqlite3VdbeSetColName(v, 1, COLNAME_NAME, "name", P4_STATIC);
        sqlite3VdbeSetColName(v, 2, COLNAME_NAME, "unique", P4_STATIC);
        while(pIdx){
          sqlite3VdbeAddOp2(v, OP_Integer, i, 1);
          sqlite3VdbeAddOp4(v, OP_String8, 0, 2, 0, pIdx->zName, 0);
          sqlite3VdbeAddOp2(v, OP_Integer, pIdx->onError!=OE_None, 3);
          sqlite3VdbeAddOp2(v, OP_ResultRow, 1, 3);
          ++i;
          pIdx = pIdx->pNext;
        }
      }
    }
  }else

  if( sqlite3StrICmp(zLeft, "database_list")==0 ){
    int i;
    if( sqlite3ReadSchema(pParse) ) goto pragma_out;
    sqlite3VdbeSetNumCols(v, 3);
    pParse->nMem = 3;
    sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "seq", P4_STATIC);
    sqlite3VdbeSetColName(v, 1, COLNAME_NAME, "name", P4_STATIC);
    sqlite3VdbeSetColName(v, 2, COLNAME_NAME, "file", P4_STATIC);
    for(i=0; i<db->nDb; i++){
      if( db->aDb[i].pBt==0 ) continue;
      assert( db->aDb[i].zName!=0 );
      sqlite3VdbeAddOp2(v, OP_Integer, i, 1);
      sqlite3VdbeAddOp4(v, OP_String8, 0, 2, 0, db->aDb[i].zName, 0);
      sqlite3VdbeAddOp4(v, OP_String8, 0, 3, 0,
           sqlite3BtreeGetFilename(db->aDb[i].pBt), 0);
      sqlite3VdbeAddOp2(v, OP_ResultRow, 1, 3);
    }
  }else

  if( sqlite3StrICmp(zLeft, "collation_list")==0 ){
    int i = 0;
    HashElem *p;
    sqlite3VdbeSetNumCols(v, 2);
    pParse->nMem = 2;
    sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "seq", P4_STATIC);
    sqlite3VdbeSetColName(v, 1, COLNAME_NAME, "name", P4_STATIC);
    for(p=sqliteHashFirst(&db->aCollSeq); p; p=sqliteHashNext(p)){
      CollSeq *pColl = (CollSeq *)sqliteHashData(p);
      sqlite3VdbeAddOp2(v, OP_Integer, i++, 1);
      sqlite3VdbeAddOp4(v, OP_String8, 0, 2, 0, pColl->zName, 0);
      sqlite3VdbeAddOp2(v, OP_ResultRow, 1, 2);
    }
  }else
#endif /* SQLITE_OMIT_SCHEMA_PRAGMAS */

#ifndef SQLITE_OMIT_FOREIGN_KEY
  if( sqlite3StrICmp(zLeft, "foreign_key_list")==0 && zRight ){
    FKey *pFK;
    Table *pTab;
    if( sqlite3ReadSchema(pParse) ) goto pragma_out;
    pTab = sqlite3FindTable(db, zRight, zDb);
    if( pTab ){
      v = sqlite3GetVdbe(pParse);
      pFK = pTab->pFKey;
      if( pFK ){
        int i = 0; 
        sqlite3VdbeSetNumCols(v, 5);
        pParse->nMem = 5;
        sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "id", P4_STATIC);
        sqlite3VdbeSetColName(v, 1, COLNAME_NAME, "seq", P4_STATIC);
        sqlite3VdbeSetColName(v, 2, COLNAME_NAME, "table", P4_STATIC);
        sqlite3VdbeSetColName(v, 3, COLNAME_NAME, "from", P4_STATIC);
        sqlite3VdbeSetColName(v, 4, COLNAME_NAME, "to", P4_STATIC);
        while(pFK){
          int j;
          for(j=0; j<pFK->nCol; j++){
            char *zCol = pFK->aCol[j].zCol;
            sqlite3VdbeAddOp2(v, OP_Integer, i, 1);
            sqlite3VdbeAddOp2(v, OP_Integer, j, 2);
            sqlite3VdbeAddOp4(v, OP_String8, 0, 3, 0, pFK->zTo, 0);
            sqlite3VdbeAddOp4(v, OP_String8, 0, 4, 0,
                              pTab->aCol[pFK->aCol[j].iFrom].zName, 0);
            sqlite3VdbeAddOp4(v, zCol ? OP_String8 : OP_Null, 0, 5, 0, zCol, 0);
            sqlite3VdbeAddOp2(v, OP_ResultRow, 1, 5);
          }
          ++i;
          pFK = pFK->pNextFrom;
        }
      }
    }
  }else
#endif /* !defined(SQLITE_OMIT_FOREIGN_KEY) */

#ifndef NDEBUG
  if( sqlite3StrICmp(zLeft, "parser_trace")==0 ){
    if( zRight ){
      if( getBoolean(zRight) ){
        sqlite3ParserTrace(stderr, "parser: ");
      }else{
        sqlite3ParserTrace(0, 0);
      }
    }
  }else
#endif

  /* Reinstall the LIKE and GLOB functions.  The variant of LIKE
  ** used will be case sensitive or not depending on the RHS.
  */
  if( sqlite3StrICmp(zLeft, "case_sensitive_like")==0 ){
    if( zRight ){
      sqlite3RegisterLikeFunctions(db, getBoolean(zRight));
    }
  }else

#ifndef SQLITE_INTEGRITY_CHECK_ERROR_MAX
# define SQLITE_INTEGRITY_CHECK_ERROR_MAX 100
#endif

#ifndef SQLITE_OMIT_INTEGRITY_CHECK
  /* Pragma "quick_check" is an experimental reduced version of 
  ** integrity_check designed to detect most database corruption
  ** without most of the overhead of a full integrity-check.
  */
  if( sqlite3StrICmp(zLeft, "integrity_check")==0
   || sqlite3StrICmp(zLeft, "quick_check")==0 
  ){
    int i, j, addr, mxErr;

    /* Code that appears at the end of the integrity check.  If no error
    ** messages have been generated, output OK.  Otherwise output the
    ** error message
    */
    static const VdbeOpList endCode[] = {
      { OP_AddImm,      1, 0,        0},    /* 0 */
      { OP_IfNeg,       1, 0,        0},    /* 1 */
      { OP_String8,     0, 3,        0},    /* 2 */
      { OP_ResultRow,   3, 1,        0},
    };

    int isQuick = (zLeft[0]=='q');

    /* Initialize the VDBE program */
    if( sqlite3ReadSchema(pParse) ) goto pragma_out;
    pParse->nMem = 6;
    sqlite3VdbeSetNumCols(v, 1);
    sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "integrity_check", P4_STATIC);

    /* Set the maximum error count */
    mxErr = SQLITE_INTEGRITY_CHECK_ERROR_MAX;
    if( zRight ){
      mxErr = atoi(zRight);
      if( mxErr<=0 ){
        mxErr = SQLITE_INTEGRITY_CHECK_ERROR_MAX;
      }
    }
    sqlite3VdbeAddOp2(v, OP_Integer, mxErr, 1);  /* reg[1] holds errors left */

    /* Do an integrity check on each database file */
    for(i=0; i<db->nDb; i++){
      HashElem *x;
      Hash *pTbls;
      int cnt = 0;

      if( OMIT_TEMPDB && i==1 ) continue;

      sqlite3CodeVerifySchema(pParse, i);
      addr = sqlite3VdbeAddOp1(v, OP_IfPos, 1); /* Halt if out of errors */
      sqlite3VdbeAddOp2(v, OP_Halt, 0, 0);
      sqlite3VdbeJumpHere(v, addr);

      /* Do an integrity check of the B-Tree
      **
      ** Begin by filling registers 2, 3, ... with the root pages numbers
      ** for all tables and indices in the database.
      */
      pTbls = &db->aDb[i].pSchema->tblHash;
      for(x=sqliteHashFirst(pTbls); x; x=sqliteHashNext(x)){
        Table *pTab = sqliteHashData(x);
        Index *pIdx;
        sqlite3VdbeAddOp2(v, OP_Integer, pTab->tnum, 2+cnt);
        cnt++;
        for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
          sqlite3VdbeAddOp2(v, OP_Integer, pIdx->tnum, 2+cnt);
          cnt++;
        }
      }
      if( cnt==0 ) continue;

      /* Make sure sufficient number of registers have been allocated */
      if( pParse->nMem < cnt+4 ){
        pParse->nMem = cnt+4;
      }

      /* Do the b-tree integrity checks */
      sqlite3VdbeAddOp3(v, OP_IntegrityCk, 2, cnt, 1);
      sqlite3VdbeChangeP5(v, i);
      addr = sqlite3VdbeAddOp1(v, OP_IsNull, 2);
      sqlite3VdbeAddOp4(v, OP_String8, 0, 3, 0,
         sqlite3MPrintf(db, "*** in database %s ***\n", db->aDb[i].zName),
         P4_DYNAMIC);
      sqlite3VdbeAddOp3(v, OP_Move, 2, 4, 1);
      sqlite3VdbeAddOp3(v, OP_Concat, 4, 3, 2);
      sqlite3VdbeAddOp2(v, OP_ResultRow, 2, 1);
      sqlite3VdbeJumpHere(v, addr);

      /* Make sure all the indices are constructed correctly.
      */
      for(x=sqliteHashFirst(pTbls); x && !isQuick; x=sqliteHashNext(x)){
        Table *pTab = sqliteHashData(x);
        Index *pIdx;
        int loopTop;

        if( pTab->pIndex==0 ) continue;
        addr = sqlite3VdbeAddOp1(v, OP_IfPos, 1);  /* Stop if out of errors */
        sqlite3VdbeAddOp2(v, OP_Halt, 0, 0);
        sqlite3VdbeJumpHere(v, addr);
        sqlite3OpenTableAndIndices(pParse, pTab, 1, OP_OpenRead);
        sqlite3VdbeAddOp2(v, OP_Integer, 0, 2);  /* reg(2) will count entries */
        loopTop = sqlite3VdbeAddOp2(v, OP_Rewind, 1, 0);
        sqlite3VdbeAddOp2(v, OP_AddImm, 2, 1);   /* increment entry count */
        for(j=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, j++){
          int jmp2;
          static const VdbeOpList idxErr[] = {
            { OP_AddImm,      1, -1,  0},
            { OP_String8,     0,  3,  0},    /* 1 */
            { OP_Rowid,       1,  4,  0},
            { OP_String8,     0,  5,  0},    /* 3 */
            { OP_String8,     0,  6,  0},    /* 4 */
            { OP_Concat,      4,  3,  3},
            { OP_Concat,      5,  3,  3},
            { OP_Concat,      6,  3,  3},
            { OP_ResultRow,   3,  1,  0},
            { OP_IfPos,       1,  0,  0},    /* 9 */
            { OP_Halt,        0,  0,  0},
          };
          sqlite3GenerateIndexKey(pParse, pIdx, 1, 3, 1);
          jmp2 = sqlite3VdbeAddOp3(v, OP_Found, j+2, 0, 3);
          addr = sqlite3VdbeAddOpList(v, ArraySize(idxErr), idxErr);
          sqlite3VdbeChangeP4(v, addr+1, "rowid ", P4_STATIC);
          sqlite3VdbeChangeP4(v, addr+3, " missing from index ", P4_STATIC);
          sqlite3VdbeChangeP4(v, addr+4, pIdx->zName, P4_STATIC);
          sqlite3VdbeJumpHere(v, addr+9);
          sqlite3VdbeJumpHere(v, jmp2);
        }
        sqlite3VdbeAddOp2(v, OP_Next, 1, loopTop+1);
        sqlite3VdbeJumpHere(v, loopTop);
        for(j=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, j++){
          static const VdbeOpList cntIdx[] = {
             { OP_Integer,      0,  3,  0},
             { OP_Rewind,       0,  0,  0},  /* 1 */
             { OP_AddImm,       3,  1,  0},
             { OP_Next,         0,  0,  0},  /* 3 */
             { OP_Eq,           2,  0,  3},  /* 4 */
             { OP_AddImm,       1, -1,  0},
             { OP_String8,      0,  2,  0},  /* 6 */
             { OP_String8,      0,  3,  0},  /* 7 */
             { OP_Concat,       3,  2,  2},
             { OP_ResultRow,    2,  1,  0},
          };
          if( pIdx->tnum==0 ) continue;
          addr = sqlite3VdbeAddOp1(v, OP_IfPos, 1);
          sqlite3VdbeAddOp2(v, OP_Halt, 0, 0);
          sqlite3VdbeJumpHere(v, addr);
          addr = sqlite3VdbeAddOpList(v, ArraySize(cntIdx), cntIdx);
          sqlite3VdbeChangeP1(v, addr+1, j+2);
          sqlite3VdbeChangeP2(v, addr+1, addr+4);
          sqlite3VdbeChangeP1(v, addr+3, j+2);
          sqlite3VdbeChangeP2(v, addr+3, addr+2);
          sqlite3VdbeJumpHere(v, addr+4);
          sqlite3VdbeChangeP4(v, addr+6, 
                     "wrong # of entries in index ", P4_STATIC);
          sqlite3VdbeChangeP4(v, addr+7, pIdx->zName, P4_STATIC);
        }
      } 
    }
    addr = sqlite3VdbeAddOpList(v, ArraySize(endCode), endCode);
    sqlite3VdbeChangeP2(v, addr, -mxErr);
    sqlite3VdbeJumpHere(v, addr+1);
    sqlite3VdbeChangeP4(v, addr+2, "ok", P4_STATIC);
  }else
#endif /* SQLITE_OMIT_INTEGRITY_CHECK */

#ifndef SQLITE_OMIT_UTF16
  /*
  **   PRAGMA encoding
  **   PRAGMA encoding = "utf-8"|"utf-16"|"utf-16le"|"utf-16be"
  **
  ** In its first form, this pragma returns the encoding of the main
  ** database. If the database is not initialized, it is initialized now.
  **
  ** The second form of this pragma is a no-op if the main database file
  ** has not already been initialized. In this case it sets the default
  ** encoding that will be used for the main database file if a new file
  ** is created. If an existing main database file is opened, then the
  ** default text encoding for the existing database is used.
  ** 
  ** In all cases new databases created using the ATTACH command are
  ** created to use the same default text encoding as the main database. If
  ** the main database has not been initialized and/or created when ATTACH
  ** is executed, this is done before the ATTACH operation.
  **
  ** In the second form this pragma sets the text encoding to be used in
  ** new database files created using this database handle. It is only
  ** useful if invoked immediately after the main database i
  */
  if( sqlite3StrICmp(zLeft, "encoding")==0 ){
    static const struct EncName {
      char *zName;
      u8 enc;
    } encnames[] = {
      { "UTF-8",    SQLITE_UTF8        },
      { "UTF8",     SQLITE_UTF8        },
      { "UTF-16le", SQLITE_UTF16LE     },
      { "UTF16le",  SQLITE_UTF16LE     },
      { "UTF-16be", SQLITE_UTF16BE     },
      { "UTF16be",  SQLITE_UTF16BE     },
      { "UTF-16",   0                  }, /* SQLITE_UTF16NATIVE */
      { "UTF16",    0                  }, /* SQLITE_UTF16NATIVE */
      { 0, 0 }
    };
    const struct EncName *pEnc;
    if( !zRight ){    /* "PRAGMA encoding" */
      if( sqlite3ReadSchema(pParse) ) goto pragma_out;
      sqlite3VdbeSetNumCols(v, 1);
      sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "encoding", P4_STATIC);
      sqlite3VdbeAddOp2(v, OP_String8, 0, 1);
      for(pEnc=&encnames[0]; pEnc->zName; pEnc++){
        if( pEnc->enc==ENC(pParse->db) ){
          sqlite3VdbeChangeP4(v, -1, pEnc->zName, P4_STATIC);
          break;
        }
      }
      sqlite3VdbeAddOp2(v, OP_ResultRow, 1, 1);
    }else{                        /* "PRAGMA encoding = XXX" */
      /* Only change the value of sqlite.enc if the database handle is not
      ** initialized. If the main database exists, the new sqlite.enc value
      ** will be overwritten when the schema is next loaded. If it does not
      ** already exists, it will be created to use the new encoding value.
      */
      if( 
        !(DbHasProperty(db, 0, DB_SchemaLoaded)) || 
        DbHasProperty(db, 0, DB_Empty) 
      ){
        for(pEnc=&encnames[0]; pEnc->zName; pEnc++){
          if( 0==sqlite3StrICmp(zRight, pEnc->zName) ){
            ENC(pParse->db) = pEnc->enc ? pEnc->enc : SQLITE_UTF16NATIVE;
            break;
          }
        }
        if( !pEnc->zName ){
          sqlite3ErrorMsg(pParse, "unsupported encoding: %s", zRight);
        }
      }
    }
  }else
#endif /* SQLITE_OMIT_UTF16 */

#ifndef SQLITE_OMIT_SCHEMA_VERSION_PRAGMAS
  /*
  **   PRAGMA [database.]schema_version
  **   PRAGMA [database.]schema_version = <integer>
  **
  **   PRAGMA [database.]user_version
  **   PRAGMA [database.]user_version = <integer>
  **
  ** The pragma's schema_version and user_version are used to set or get
  ** the value of the schema-version and user-version, respectively. Both
  ** the schema-version and the user-version are 32-bit signed integers
  ** stored in the database header.
  **
  ** The schema-cookie is usually only manipulated internally by SQLite. It
  ** is incremented by SQLite whenever the database schema is modified (by
  ** creating or dropping a table or index). The schema version is used by
  ** SQLite each time a query is executed to ensure that the internal cache
  ** of the schema used when compiling the SQL query matches the schema of
  ** the database against which the compiled query is actually executed.
  ** Subverting this mechanism by using "PRAGMA schema_version" to modify
  ** the schema-version is potentially dangerous and may lead to program
  ** crashes or database corruption. Use with caution!
  **
  ** The user-version is not used internally by SQLite. It may be used by
  ** applications for any purpose.
  */
  if( sqlite3StrICmp(zLeft, "schema_version")==0 
   || sqlite3StrICmp(zLeft, "user_version")==0 
   || sqlite3StrICmp(zLeft, "freelist_count")==0 
  ){
    int iCookie;   /* Cookie index. 0 for schema-cookie, 6 for user-cookie. */
    sqlite3VdbeUsesBtree(v, iDb);
    switch( zLeft[0] ){
      case 's': case 'S':
        iCookie = 0;
        break;
      case 'f': case 'F':
        iCookie = 1;
        iDb = (-1*(iDb+1));
        assert(iDb<=0);
        break;
      default:
        iCookie = 5;
        break;
    }

    if( zRight && iDb>=0 ){
      /* Write the specified cookie value */
      static const VdbeOpList setCookie[] = {
        { OP_Transaction,    0,  1,  0},    /* 0 */
        { OP_Integer,        0,  1,  0},    /* 1 */
        { OP_SetCookie,      0,  0,  1},    /* 2 */
      };
      int addr = sqlite3VdbeAddOpList(v, ArraySize(setCookie), setCookie);
      sqlite3VdbeChangeP1(v, addr, iDb);
      sqlite3VdbeChangeP1(v, addr+1, atoi(zRight));
      sqlite3VdbeChangeP1(v, addr+2, iDb);
      sqlite3VdbeChangeP2(v, addr+2, iCookie);
    }else{
      /* Read the specified cookie value */
      static const VdbeOpList readCookie[] = {
        { OP_ReadCookie,      0,  1,  0},    /* 0 */
        { OP_ResultRow,       1,  1,  0}
      };
      int addr = sqlite3VdbeAddOpList(v, ArraySize(readCookie), readCookie);
      sqlite3VdbeChangeP1(v, addr, iDb);
      sqlite3VdbeChangeP3(v, addr, iCookie);
      sqlite3VdbeSetNumCols(v, 1);
      sqlite3VdbeSetColName(v, 0, COLNAME_NAME, zLeft, P4_TRANSIENT);
    }
  }else
#endif /* SQLITE_OMIT_SCHEMA_VERSION_PRAGMAS */

#if defined(SQLITE_DEBUG) || defined(SQLITE_TEST)
  /*
  ** Report the current state of file logs for all databases
  */
  if( sqlite3StrICmp(zLeft, "lock_status")==0 ){
    static const char *const azLockName[] = {
      "unlocked", "shared", "reserved", "pending", "exclusive"
    };
    int i;
    Vdbe *v = sqlite3GetVdbe(pParse);
    sqlite3VdbeSetNumCols(v, 2);
    pParse->nMem = 2;
    sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "database", P4_STATIC);
    sqlite3VdbeSetColName(v, 1, COLNAME_NAME, "status", P4_STATIC);
    for(i=0; i<db->nDb; i++){
      Btree *pBt;
      Pager *pPager;
      const char *zState = "unknown";
      int j;
      if( db->aDb[i].zName==0 ) continue;
      sqlite3VdbeAddOp4(v, OP_String8, 0, 1, 0, db->aDb[i].zName, P4_STATIC);
      pBt = db->aDb[i].pBt;
      if( pBt==0 || (pPager = sqlite3BtreePager(pBt))==0 ){
        zState = "closed";
      }else if( sqlite3_file_control(db, i ? db->aDb[i].zName : 0, 
                                     SQLITE_FCNTL_LOCKSTATE, &j)==SQLITE_OK ){
         zState = azLockName[j];
      }
      sqlite3VdbeAddOp4(v, OP_String8, 0, 2, 0, zState, P4_STATIC);
      sqlite3VdbeAddOp2(v, OP_ResultRow, 1, 2);
    }

  }else
#endif

#ifdef SQLITE_SSE
  /*
  ** Check to see if the sqlite_statements table exists.  Create it
  ** if it does not.
  */
  if( sqlite3StrICmp(zLeft, "create_sqlite_statement_table")==0 ){
    extern int sqlite3CreateStatementsTable(Parse*);
    sqlite3CreateStatementsTable(pParse);
  }else
#endif

#if SQLITE_HAS_CODEC
  if( sqlite3StrICmp(zLeft, "key")==0 ){
    sqlite3_key(db, zRight, strlen(zRight));
  }else
#endif
#if SQLITE_HAS_CODEC || defined(SQLITE_ENABLE_CEROD)
  if( sqlite3StrICmp(zLeft, "activate_extensions")==0 ){
#if SQLITE_HAS_CODEC
    if( sqlite3StrNICmp(zRight, "see-", 4)==0 ){
      extern void sqlite3_activate_see(const char*);
      sqlite3_activate_see(&zRight[4]);
    }
#endif
#ifdef SQLITE_ENABLE_CEROD
    if( sqlite3StrNICmp(zRight, "cerod-", 6)==0 ){
      extern void sqlite3_activate_cerod(const char*);
      sqlite3_activate_cerod(&zRight[6]);
    }
#endif
  }
#endif

  {}

  if( v ){
    /* Code an OP_Expire at the end of each PRAGMA program to cause
    ** the VDBE implementing the pragma to expire. Most (all?) pragmas
    ** are only valid for a single execution.
    */
    sqlite3VdbeAddOp2(v, OP_Expire, 1, 0);

    /*
    ** Reset the safety level, in case the fullfsync flag or synchronous
    ** setting changed.
    */
#ifndef SQLITE_OMIT_PAGER_PRAGMAS
    if( db->autoCommit ){
      sqlite3BtreeSetSafetyLevel(pDb->pBt, pDb->safety_level,
                 (db->flags&SQLITE_FullFSync)!=0);
    }
#endif
  }
pragma_out:
  sqlite3DbFree(db, zLeft);
  sqlite3DbFree(db, zRight);
}
/*
** 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
** database.  iDb==1 should never be used.  iDb>=2 is used for
** auxiliary databases.  Return one of the SQLITE_ error codes to
** indicate success or failure.
*/
static int sqlite3InitOne(sqlite3 *db, int iDb, char **pzErrMsg){
  int rc;
  BtCursor *curMain;
  int size;
  Table *pTab;
  char const *azArg[5];
  char zDbNum[30];
  int meta[10];
  InitData initData;
  char const *zMasterSchema;
  char const *zMasterName = SCHEMA_TABLE(iDb);

  /*
  ** The master database table has a structure like this
  */
  static const char master_schema[] = 
     "CREATE TABLE sqlite_master(\n"
     "  type text,\n"
     "  name text,\n"
     "  tbl_name text,\n"
     "  rootpage integer,\n"
     "  sql text\n"
     ")"
  ;
#ifndef SQLITE_OMIT_TEMPDB
  static const char temp_master_schema[] = 
     "CREATE TEMP TABLE sqlite_temp_master(\n"
     "  type text,\n"
     "  name text,\n"
     "  tbl_name text,\n"
     "  rootpage integer,\n"
     "  sql text\n"
     ")"
  ;
#else
  #define temp_master_schema 0
#endif

  assert( iDb>=0 && iDb<db->nDb );

  /* zMasterSchema and zInitScript are set to point at the master schema
  ** and initialisation script appropriate for the database being
  ** initialised. zMasterName is the name of the master table.
  */
  if( !OMIT_TEMPDB && iDb==1 ){
    zMasterSchema = temp_master_schema;
  }else{
    zMasterSchema = master_schema;
  }
  zMasterName = SCHEMA_TABLE(iDb);

  /* Construct the schema tables.  */
  sqlite3SafetyOff(db);
  azArg[0] = zMasterName;
  azArg[1] = "1";
  azArg[2] = zMasterSchema;
  sprintf(zDbNum, "%d", iDb);
  azArg[3] = zDbNum;
  azArg[4] = 0;
  initData.db = db;
  initData.pzErrMsg = pzErrMsg;
  rc = sqlite3InitCallback(&initData, 4, (char **)azArg, 0);
  if( rc!=SQLITE_OK ){
    sqlite3SafetyOn(db);
    return rc;
  }
  pTab = sqlite3FindTable(db, zMasterName, db->aDb[iDb].zName);
  if( pTab ){
    pTab->readOnly = 1;
  }
  sqlite3SafetyOn(db);

  /* Create a cursor to hold the database open
  */
  if( db->aDb[iDb].pBt==0 ){
    if( !OMIT_TEMPDB && iDb==1 ) DbSetProperty(db, 1, DB_SchemaLoaded);
    return SQLITE_OK;
  }
  rc = sqlite3BtreeCursor(db->aDb[iDb].pBt, MASTER_ROOT, 0, 0, 0, &curMain);
  if( rc!=SQLITE_OK && rc!=SQLITE_EMPTY ){
    sqlite3SetString(pzErrMsg, sqlite3ErrStr(rc), (char*)0);
    return rc;
  }

  /* Get the database meta information.
  **
  ** Meta values are as follows:
  **    meta[0]   Schema cookie.  Changes with each schema change.
  **    meta[1]   File format of schema layer.
  **    meta[2]   Size of the page cache.
  **    meta[3]   Use freelist if 0.  Autovacuum if greater than zero.
  **    meta[4]   Db text encoding. 1:UTF-8 3:UTF-16 LE 4:UTF-16 BE
  **    meta[5]   The user cookie. Used by the application.
  **    meta[6]   
  **    meta[7]
  **    meta[8]
  **    meta[9]
  **
  ** Note: The hash defined SQLITE_UTF* symbols in sqliteInt.h correspond to
  ** the possible values of meta[4].
  */
  if( rc==SQLITE_OK ){
    int i;
    for(i=0; rc==SQLITE_OK && i<sizeof(meta)/sizeof(meta[0]); i++){
      rc = sqlite3BtreeGetMeta(db->aDb[iDb].pBt, i+1, (u32 *)&meta[i]);
    }
    if( rc ){
      sqlite3SetString(pzErrMsg, sqlite3ErrStr(rc), (char*)0);
      sqlite3BtreeCloseCursor(curMain);
      return rc;
    }
  }else{
    memset(meta, 0, sizeof(meta));
  }
  db->aDb[iDb].schema_cookie = meta[0];

  /* If opening a non-empty database, check the text encoding. For the
  ** main database, set sqlite3.enc to the encoding of the main database.
  ** For an attached db, it is an error if the encoding is not the same
  ** as sqlite3.enc.
  */
  if( meta[4] ){  /* text encoding */
    if( iDb==0 ){
      /* If opening the main database, set db->enc. */
      db->enc = (u8)meta[4];
      db->pDfltColl = sqlite3FindCollSeq(db, db->enc, "BINARY", 6, 0);
    }else{
      /* If opening an attached database, the encoding much match db->enc */
      if( meta[4]!=db->enc ){
        sqlite3BtreeCloseCursor(curMain);
        sqlite3SetString(pzErrMsg, "attached databases must use the same"
            " text encoding as main database", (char*)0);
        return SQLITE_ERROR;
      }
    }
  }

  size = meta[2];
  if( size==0 ){ size = MAX_PAGES; }
  db->aDb[iDb].cache_size = size;

  if( iDb==0 ){
    db->file_format = meta[1];
    if( db->file_format==0 ){
      /* This happens if the database was initially empty */
      db->file_format = 1;
    }

    if( db->file_format==2 || db->file_format==3 ){
      /* File format 2 is treated exactly as file format 1. New 
      ** databases are created with file format 1.
      */ 
      db->file_format = 1;
    }
  }

  /*
  ** file_format==1    Version 3.0.0.
  ** file_format==2    Version 3.1.3.
  ** file_format==3    Version 3.1.4.
  **
  ** Version 3.0 can only use files with file_format==1. Version 3.1.3
  ** can read and write files with file_format==1 or file_format==2.
  ** Version 3.1.4 can read and write file formats 1, 2 and 3.
  */
  if( meta[1]>3 ){
    sqlite3BtreeCloseCursor(curMain);
    sqlite3SetString(pzErrMsg, "unsupported file format", (char*)0);
    return SQLITE_ERROR;
  }

  sqlite3BtreeSetCacheSize(db->aDb[iDb].pBt, db->aDb[iDb].cache_size);

  /* Read the schema information out of the schema tables
  */
  assert( db->init.busy );
  if( rc==SQLITE_EMPTY ){
    /* For an empty database, there is nothing to read */
    rc = SQLITE_OK;
  }else{
    char *zSql;
    zSql = sqlite3MPrintf(
        "SELECT name, rootpage, sql, '%s' FROM '%q'.%s",
        zDbNum, db->aDb[iDb].zName, zMasterName);
    sqlite3SafetyOff(db);
    rc = sqlite3_exec(db, zSql, sqlite3InitCallback, &initData, 0);
    sqlite3SafetyOn(db);
    sqliteFree(zSql);
    sqlite3BtreeCloseCursor(curMain);
  }
  if( sqlite3_malloc_failed ){
    sqlite3SetString(pzErrMsg, "out of memory", (char*)0);
    rc = SQLITE_NOMEM;
    sqlite3ResetInternalSchema(db, 0);
  }
  if( rc==SQLITE_OK ){
    DbSetProperty(db, iDb, DB_SchemaLoaded);
  }else{
    sqlite3ResetInternalSchema(db, iDb);
  }
  return rc;
}
Esempio n. 15
0
/*
** This routine generates code that opens the sqlite_stat1 table for
** writing with cursor iStatCur. If the library was built with the
** SQLITE_ENABLE_STAT2 macro defined, then the sqlite_stat2 table is
** opened for writing using cursor (iStatCur+1)
**
** If the sqlite_stat1 tables does not previously exist, it is created.
** Similarly, if the sqlite_stat2 table does not exist and the library
** is compiled with SQLITE_ENABLE_STAT2 defined, it is created. 
**
** Argument zWhere may be a pointer to a buffer containing a table name,
** or it may be a NULL pointer. If it is not NULL, then all entries in
** the sqlite_stat1 and (if applicable) sqlite_stat2 tables associated
** with the named table are deleted. If zWhere==0, then code is generated
** to delete all stat table entries.
*/
static void openStatTable(
  Parse *pParse,          /* Parsing context */
  int iDb,                /* The database we are looking in */
  int iStatCur,           /* Open the sqlite_stat1 table on this cursor */
  const char *zWhere,     /* Delete entries for this table or index */
  const char *zWhereType  /* Either "tbl" or "idx" */
){
  static const struct {
    const char *zName;
    const char *zCols;
  } aTable[] = {
    { "sqlite_stat1", "tbl,idx,stat" },
#ifdef SQLITE_ENABLE_STAT2
    { "sqlite_stat2", "tbl,idx,sampleno,sample" },
#endif
  };

  int aRoot[] = {0, 0};
  u8 aCreateTbl[] = {0, 0};

  int i;
  sqlite3 *db = pParse->db;
  Db *pDb;
  Vdbe *v = sqlite3GetVdbe(pParse);
  if( v==0 ) return;
  assert( sqlite3BtreeHoldsAllMutexes(db) );
  assert( sqlite3VdbeDb(v)==db );
  pDb = &db->aDb[iDb];

  for(i=0; i<ArraySize(aTable); i++){
    const char *zTab = aTable[i].zName;
    Table *pStat;
    if( (pStat = sqlite3FindTable(db, zTab, pDb->zName))==0 ){
      /* The sqlite_stat[12] table does not exist. Create it. Note that a 
      ** side-effect of the CREATE TABLE statement is to leave the rootpage 
      ** of the new table in register pParse->regRoot. This is important 
      ** because the OpenWrite opcode below will be needing it. */
      sqlite3NestedParse(pParse,
          "CREATE TABLE %Q.%s(%s)", pDb->zName, zTab, aTable[i].zCols
      );
      aRoot[i] = pParse->regRoot;
      aCreateTbl[i] = 1;
    }else{
      /* The table already exists. If zWhere is not NULL, delete all entries 
      ** associated with the table zWhere. If zWhere is NULL, delete the
      ** entire contents of the table. */
      aRoot[i] = pStat->tnum;
      sqlite3TableLock(pParse, iDb, aRoot[i], 1, zTab);
      if( zWhere ){
        sqlite3NestedParse(pParse,
           "DELETE FROM %Q.%s WHERE %s=%Q", pDb->zName, zTab, zWhereType, zWhere
        );
      }else{
        /* The sqlite_stat[12] table already exists.  Delete all rows. */
        sqlite3VdbeAddOp2(v, OP_Clear, aRoot[i], iDb);
      }
    }
  }

  /* Open the sqlite_stat[12] tables for writing. */
  for(i=0; i<ArraySize(aTable); i++){
    sqlite3VdbeAddOp3(v, OP_OpenWrite, iStatCur+i, aRoot[i], iDb);
    sqlite3VdbeChangeP4(v, -1, (char *)3, P4_INT32);
    sqlite3VdbeChangeP5(v, aCreateTbl[i]);
  }
}
Esempio n. 16
0
/*
** This function is called after an "ALTER TABLE ... ADD" statement
** has been parsed. Argument pColDef contains the text of the new
** column definition.
**
** The Table structure pParse->pNewTable was extended to include
** the new column during parsing.
在“ALTER TABLE…添加“声明解析后这个函数被调用。
参数pColDef包含新列定义的文本。
表结构pParse - > pNewTable扩大到包括在解析新列。
*/
void sqlite3AlterFinishAddColumn(Parse *pParse, Token *pColDef){
  Table *pNew;              /* Copy of pParse->pNewTable pParse->pNew表的副本*/
  Table *pTab;              /* Table being altered 被修改的表*/
  int iDb;                  /* Database number 数据库数*/
  const char *zDb;          /* Database name 数据库名*/
  const char *zTab;         /* Table name 表名*/
  char *zCol;               /* Null-terminated column definition 空值终止列定义*/
  Column *pCol;             /* The new column 新列*/
  Expr *pDflt;              /* Default value for the new column 为新列默认数值*/
  sqlite3 *db;              /* The database connection; 数据库的连接*/

  db = pParse->db;
  if( pParse->nErr || db->mallocFailed ) return;
  pNew = pParse->pNewTable;
  assert( pNew );

  assert( sqlite3BtreeHoldsAllMutexes(db) );
  iDb = sqlite3SchemaToIndex(db, pNew->pSchema);
  zDb = db->aDb[iDb].zName;
  zTab = &pNew->zName[16];  /* Skip the "sqlite_altertab_" prefix on the name 跳过“sqlite_altertab_”前缀的名称*/
  pCol = &pNew->aCol[pNew->nCol-1];
  pDflt = pCol->pDflt;
  pTab = sqlite3FindTable(db, zTab, zDb);
  assert( pTab );

#ifndef SQLITE_OMIT_AUTHORIZATION
  /* Invoke the authorization callback. 调用授权回调*/
  if( sqlite3AuthCheck(pParse, SQLITE_ALTER_TABLE, zDb, pTab->zName, 0) ){
    return;
  }
#endif

  /* If the default value for the new column was specified with a 
  ** literal NULL, then set pDflt to 0. This simplifies checking
  ** for an SQL NULL default below.
  如果新列的默认值是用文字指定NULL,那么pDflt设置为0。
  这简化了检查SQL空下面的默认。
  */
  if( pDflt && pDflt->op==TK_NULL ){
    pDflt = 0;
  }

  /* Check that the new column is not specified as PRIMARY KEY or UNIQUE.
  ** If there is a NOT NULL constraint, then the default value for the
  ** column must not be NULL.
 检查新列没有指定主键或唯一的。
如果有一个非空约束,然后列的默认值不能为空。
  */
  if( pCol->isPrimKey ){
    sqlite3ErrorMsg(pParse, "Cannot add a PRIMARY KEY column");
    return;
  }
  if( pNew->pIndex ){
    sqlite3ErrorMsg(pParse, "Cannot add a UNIQUE column");
    return;
  }
  if( (db->flags&SQLITE_ForeignKeys) && pNew->pFKey && pDflt ){
    sqlite3ErrorMsg(pParse, 
        "Cannot add a REFERENCES column with non-NULL default value");
    return;
  }
  if( pCol->notNull && !pDflt ){
    sqlite3ErrorMsg(pParse, 
        "Cannot add a NOT NULL column with default value NULL");
    return;
  }

  /* Ensure the default expression is something that sqlite3ValueFromExpr()
  ** can handle (i.e. not CURRENT_TIME etc.)
  确保默认表达式是sqlite3ValueFromExpr()可以处理的事(即不是当前时间等。)
  */
  if( pDflt ){
    sqlite3_value *pVal;
    if( sqlite3ValueFromExpr(db, pDflt, SQLITE_UTF8, SQLITE_AFF_NONE, &pVal) ){
      db->mallocFailed = 1;
      return;
    }
    if( !pVal ){
      sqlite3ErrorMsg(pParse, "Cannot add a column with non-constant default");
      return;
    }
    sqlite3ValueFree(pVal);
  }

  /* Modify the CREATE TABLE statement. 修改CREATE TABLE语句。*/
  zCol = sqlite3DbStrNDup(db, (char*)pColDef->z, pColDef->n);
  if( zCol ){
    char *zEnd = &zCol[pColDef->n-1];
    int savedDbFlags = db->flags;
    while( zEnd>zCol && (*zEnd==';' || sqlite3Isspace(*zEnd)) ){
      *zEnd-- = '\0';
    }
    db->flags |= SQLITE_PreferBuiltin;
    sqlite3NestedParse(pParse, 
        "UPDATE \"%w\".%s SET "
          "sql = substr(sql,1,%d) || ', ' || %Q || substr(sql,%d) "
        "WHERE type = 'table' AND name = %Q", 
      zDb, SCHEMA_TABLE(iDb), pNew->addColOffset, zCol, pNew->addColOffset+1,
      zTab
    );
    sqlite3DbFree(db, zCol);
    db->flags = savedDbFlags;
  }

  /* If the default value of the new column is NULL, then set the file
  ** format to 2. If the default value of the new column is not NULL,
  ** the file format becomes 3.
  如果新列的默认值为空,那么将文件格式设置为2。如果新列的默认值不为空,文件格式变成3。
  */
  sqlite3MinimumFileFormat(pParse, iDb, pDflt ? 3 : 2);

  /* Reload the schema of the modified table. 重新加载修改后的表的模式。*/
  reloadTableSchema(pParse, pTab, pTab->zName);
}
Esempio n. 17
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
** database.  iDb==1 should never be used.  iDb>=2 is used for
** auxiliary databases.  Return one of the SQLITE_ error codes to
** indicate success or failure.
*/
static int sqlite3InitOne(sqlite3 *db, int iDb, char **pzErrMsg){
  int rc;
  BtCursor *curMain;
  int size;
  Table *pTab;
  Db *pDb;
  char const *azArg[4];
  int meta[10];
  InitData initData;
  char const *zMasterSchema;
  char const *zMasterName = SCHEMA_TABLE(iDb);

  /*
  ** The master database table has a structure like this
  */
  static const char master_schema[] = 
     "CREATE TABLE sqlite_master(\n"
     "  type text,\n"
     "  name text,\n"
     "  tbl_name text,\n"
     "  rootpage integer,\n"
     "  sql text\n"
     ")"
  ;
#ifndef SQLITE_OMIT_TEMPDB
  static const char temp_master_schema[] = 
     "CREATE TEMP TABLE sqlite_temp_master(\n"
     "  type text,\n"
     "  name text,\n"
     "  tbl_name text,\n"
     "  rootpage integer,\n"
     "  sql text\n"
     ")"
  ;
#else
  #define temp_master_schema 0
#endif

  assert( iDb>=0 && iDb<db->nDb );
  assert( db->aDb[iDb].pSchema );

  /* zMasterSchema and zInitScript are set to point at the master schema
  ** and initialisation script appropriate for the database being
  ** initialised. zMasterName is the name of the master table.
  */
  if( !OMIT_TEMPDB && iDb==1 ){
    zMasterSchema = temp_master_schema;
  }else{
    zMasterSchema = master_schema;
  }
  zMasterName = SCHEMA_TABLE(iDb);

  /* Construct the schema tables.  */
  sqlite3SafetyOff(db);
  azArg[0] = zMasterName;
  azArg[1] = "1";
  azArg[2] = zMasterSchema;
  azArg[3] = 0;
  initData.db = db;
  initData.iDb = iDb;
  initData.pzErrMsg = pzErrMsg;
  rc = sqlite3InitCallback(&initData, 3, (char **)azArg, 0);
  if( rc ){
    sqlite3SafetyOn(db);
    return initData.rc;
  }
  pTab = sqlite3FindTable(db, zMasterName, db->aDb[iDb].zName);
  if( pTab ){
    pTab->readOnly = 1;
  }
  sqlite3SafetyOn(db);

  /* Create a cursor to hold the database open
  */
  pDb = &db->aDb[iDb];
  if( pDb->pBt==0 ){
    if( !OMIT_TEMPDB && iDb==1 ){
      DbSetProperty(db, 1, DB_SchemaLoaded);
    }
    return SQLITE_OK;
  }
  rc = sqlite3BtreeCursor(pDb->pBt, MASTER_ROOT, 0, 0, 0, &curMain);
  if( rc!=SQLITE_OK && rc!=SQLITE_EMPTY ){
    sqlite3SetString(pzErrMsg, sqlite3ErrStr(rc), (char*)0);
    return rc;
  }

  /* Get the database meta information.
  **
  ** Meta values are as follows:
  **    meta[0]   Schema cookie.  Changes with each schema change.
  **    meta[1]   File format of schema layer.
  **    meta[2]   Size of the page cache.
  **    meta[3]   Use freelist if 0.  Autovacuum if greater than zero.
  **    meta[4]   Db text encoding. 1:UTF-8 2:UTF-16LE 3:UTF-16BE
  **    meta[5]   The user cookie. Used by the application.
  **    meta[6]   
  **    meta[7]
  **    meta[8]
  **    meta[9]
  **
  ** Note: The #defined SQLITE_UTF* symbols in sqliteInt.h correspond to
  ** the possible values of meta[4].
  */
  if( rc==SQLITE_OK ){
    int i;
    for(i=0; rc==SQLITE_OK && i<sizeof(meta)/sizeof(meta[0]); i++){
      rc = sqlite3BtreeGetMeta(pDb->pBt, i+1, (u32 *)&meta[i]);
    }
    if( rc ){
      sqlite3SetString(pzErrMsg, sqlite3ErrStr(rc), (char*)0);
      sqlite3BtreeCloseCursor(curMain);
      return rc;
    }
  }else{
    memset(meta, 0, sizeof(meta));
  }
  pDb->pSchema->schema_cookie = meta[0];

  /* If opening a non-empty database, check the text encoding. For the
  ** main database, set sqlite3.enc to the encoding of the main database.
  ** For an attached db, it is an error if the encoding is not the same
  ** as sqlite3.enc.
  */
  if( meta[4] ){  /* text encoding */
    if( iDb==0 ){
      /* If opening the main database, set ENC(db). */
      ENC(db) = (u8)meta[4];
      db->pDfltColl = sqlite3FindCollSeq(db, SQLITE_UTF8, "BINARY", 6, 0);
    }else{
      /* If opening an attached database, the encoding much match ENC(db) */
      if( meta[4]!=ENC(db) ){
        sqlite3BtreeCloseCursor(curMain);
        sqlite3SetString(pzErrMsg, "attached databases must use the same"
            " text encoding as main database", (char*)0);
        return SQLITE_ERROR;
      }
    }
  }else{
    DbSetProperty(db, iDb, DB_Empty);
  }
  pDb->pSchema->enc = ENC(db);

  size = meta[2];
  if( size==0 ){ size = MAX_PAGES; }
  pDb->pSchema->cache_size = size;
  sqlite3BtreeSetCacheSize(pDb->pBt, pDb->pSchema->cache_size);

  /*
  ** file_format==1    Version 3.0.0.
  ** file_format==2    Version 3.1.3.  // ALTER TABLE ADD COLUMN
  ** file_format==3    Version 3.1.4.  // ditto but with non-NULL defaults
  ** file_format==4    Version 3.3.0.  // DESC indices.  Boolean constants
  */
  pDb->pSchema->file_format = meta[1];
  if( pDb->pSchema->file_format==0 ){
    pDb->pSchema->file_format = 1;
  }
  if( pDb->pSchema->file_format>SQLITE_MAX_FILE_FORMAT ){
    sqlite3BtreeCloseCursor(curMain);
    sqlite3SetString(pzErrMsg, "unsupported file format", (char*)0);
    return SQLITE_ERROR;
  }


  /* Read the schema information out of the schema tables
  */
  assert( db->init.busy );
  if( rc==SQLITE_EMPTY ){
    /* For an empty database, there is nothing to read */
    rc = SQLITE_OK;
  }else{
    char *zSql;
    zSql = sqlite3MPrintf(
        "SELECT name, rootpage, sql FROM '%q'.%s",
        db->aDb[iDb].zName, zMasterName);
    sqlite3SafetyOff(db);
    rc = sqlite3_exec(db, zSql, sqlite3InitCallback, &initData, 0);
    if( rc==SQLITE_ABORT ) rc = initData.rc;
    sqlite3SafetyOn(db);
    sqliteFree(zSql);
#ifndef SQLITE_OMIT_ANALYZE
    if( rc==SQLITE_OK ){
      sqlite3AnalysisLoad(db, iDb);
    }
#endif
    sqlite3BtreeCloseCursor(curMain);
  }
  if( sqlite3MallocFailed() ){
    /* sqlite3SetString(pzErrMsg, "out of memory", (char*)0); */
    rc = SQLITE_NOMEM;
    sqlite3ResetInternalSchema(db, 0);
  }
  if( rc==SQLITE_OK ){
    DbSetProperty(db, iDb, DB_SchemaLoaded);
  }else{
    sqlite3ResetInternalSchema(db, iDb);
  }
  return rc;
}
Esempio n. 18
0
/*
** Generate code to implement the "ALTER TABLE xxx RENAME TO yyy"
** command.
*/
void sqlite3AlterRenameTable(
  Parse *pParse,            /* Parser context. */
  SrcList *pSrc,            /* The table to rename. */
  Token *pName              /* The new table name. */
){
  int iDb;                  /* Database that contains the table */
  char *zDb;                /* Name of database iDb */
  Table *pTab;              /* Table being renamed */
  char *zName = 0;          /* NULL-terminated version of pName */
  sqlite3 *db = pParse->db; /* Database connection */
  int nTabName;             /* Number of UTF-8 characters in zTabName */
  const char *zTabName;     /* Original name of the table */
  Vdbe *v;
#ifndef SQLITE_OMIT_TRIGGER
  char *zWhere = 0;         /* Where clause to locate temp triggers */
#endif
  VTable *pVTab = 0;        /* Non-zero if this is a v-tab with an xRename() */
  int savedDbFlags;         /* Saved value of db->flags */

  savedDbFlags = db->flags;
  if( NEVER(db->mallocFailed) ) goto exit_rename_table;
  assert( pSrc->nSrc==1 );
  assert( sqlite3BtreeHoldsAllMutexes(pParse->db) );

  pTab = sqlite3LocateTableItem(pParse, 0, &pSrc->a[0]);
  if( !pTab ) goto exit_rename_table;
  iDb = sqlite3SchemaToIndex(pParse->db, pTab->pSchema);
  zDb = db->aDb[iDb].zName;
  db->flags |= SQLITE_PreferBuiltin;

  /* Get a NULL terminated version of the new table name. */
  zName = sqlite3NameFromToken(db, pName);
  if( !zName ) goto exit_rename_table;

  /* Check that a table or index named 'zName' does not already exist
  ** in database iDb. If so, this is an error.
  */
  if( sqlite3FindTable(db, zName, zDb) || sqlite3FindIndex(db, zName, zDb) ){
    sqlite3ErrorMsg(pParse,
        "there is already another table or index with this name: %s", zName);
    goto exit_rename_table;
  }

  /* Make sure it is not a system table being altered, or a reserved name
  ** that the table is being renamed to.
  */
  if( SQLITE_OK!=isSystemTable(pParse, pTab->zName) ){
    goto exit_rename_table;
  }
  if( SQLITE_OK!=sqlite3CheckObjectName(pParse, zName) ){ goto
    exit_rename_table;
  }

#ifndef SQLITE_OMIT_VIEW
  if( pTab->pSelect ){
    sqlite3ErrorMsg(pParse, "view %s may not be altered", pTab->zName);
    goto exit_rename_table;
  }
#endif

#ifndef SQLITE_OMIT_AUTHORIZATION
  /* Invoke the authorization callback. */
  if( sqlite3AuthCheck(pParse, SQLITE_ALTER_TABLE, zDb, pTab->zName, 0) ){
    goto exit_rename_table;
  }
#endif

#ifndef SQLITE_OMIT_VIRTUALTABLE
  if( sqlite3ViewGetColumnNames(pParse, pTab) ){
    goto exit_rename_table;
  }
  if( IsVirtual(pTab) ){
    pVTab = sqlite3GetVTable(db, pTab);
    if( pVTab->pVtab->pModule->xRename==0 ){
      pVTab = 0;
    }
  }
#endif

  /* Begin a transaction for database iDb.
  ** Then modify the schema cookie (since the ALTER TABLE modifies the
  ** schema). Open a statement transaction if the table is a virtual
  ** table.
  */
  v = sqlite3GetVdbe(pParse);
  if( v==0 ){
    goto exit_rename_table;
  }
  sqlite3BeginWriteOperation(pParse, pVTab!=0, iDb);
  sqlite3ChangeCookie(pParse, iDb);

  /* If this is a virtual table, invoke the xRename() function if
  ** one is defined. The xRename() callback will modify the names
  ** of any resources used by the v-table implementation (including other
  ** SQLite tables) that are identified by the name of the virtual table.
  */
#ifndef SQLITE_OMIT_VIRTUALTABLE
  if( pVTab ){
    int i = ++pParse->nMem;
    sqlite3VdbeLoadString(v, i, zName);
    sqlite3VdbeAddOp4(v, OP_VRename, i, 0, 0,(const char*)pVTab, P4_VTAB);
    sqlite3MayAbort(pParse);
  }
#endif

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

#if !defined(SQLITE_OMIT_FOREIGN_KEY) && !defined(SQLITE_OMIT_TRIGGER)
  if( db->flags&SQLITE_ForeignKeys ){
    /* If foreign-key support is enabled, rewrite the CREATE TABLE
    ** statements corresponding to all child tables of foreign key constraints
    ** for which the renamed table is the parent table.  */
    if( (zWhere=whereForeignKeys(pParse, pTab))!=0 ){
      sqlite3NestedParse(pParse,
          "UPDATE \"%w\".%s SET "
              "sql = sqlite_rename_parent(sql, %Q, %Q) "
              "WHERE %s;", zDb, SCHEMA_TABLE(iDb), zTabName, zName, zWhere);
      sqlite3DbFree(db, zWhere);
    }
  }
#endif

  /* Modify the sqlite_master table to use the new table name. */
  sqlite3NestedParse(pParse,
      "UPDATE %Q.%s SET "
#ifdef SQLITE_OMIT_TRIGGER
          "sql = sqlite_rename_table(sql, %Q), "
#else
          "sql = CASE "
            "WHEN type = 'trigger' THEN sqlite_rename_trigger(sql, %Q)"
            "ELSE sqlite_rename_table(sql, %Q) END, "
#endif
          "tbl_name = %Q, "
          "name = CASE "
            "WHEN type='table' THEN %Q "
            "WHEN name LIKE 'sqlite_autoindex%%' AND type='index' THEN "
             "'sqlite_autoindex_' || %Q || substr(name,%d+18) "
            "ELSE name END "
      "WHERE tbl_name=%Q COLLATE nocase AND "
          "(type='table' OR type='index' OR type='trigger');",
      zDb, SCHEMA_TABLE(iDb), zName, zName, zName,
#ifndef SQLITE_OMIT_TRIGGER
      zName,
#endif
      zName, nTabName, zTabName
  );

#ifndef SQLITE_OMIT_AUTOINCREMENT
  /* If the sqlite_sequence table exists in this database, then update
  ** it with the new table name.
  */
  if( sqlite3FindTable(db, "sqlite_sequence", zDb) ){
    sqlite3NestedParse(pParse,
        "UPDATE \"%w\".sqlite_sequence set name = %Q WHERE name = %Q",
        zDb, zName, pTab->zName);
  }
#endif

#ifndef SQLITE_OMIT_TRIGGER
  /* If there are TEMP triggers on this table, modify the sqlite_temp_master
  ** table. Don't do this if the table being ALTERed is itself located in
  ** the temp database.
  */
  if( (zWhere=whereTempTriggers(pParse, pTab))!=0 ){
    sqlite3NestedParse(pParse,
        "UPDATE sqlite_temp_master SET "
            "sql = sqlite_rename_trigger(sql, %Q), "
            "tbl_name = %Q "
            "WHERE %s;", zName, zName, zWhere);
    sqlite3DbFree(db, zWhere);
  }
#endif

#if !defined(SQLITE_OMIT_FOREIGN_KEY) && !defined(SQLITE_OMIT_TRIGGER)
  if( db->flags&SQLITE_ForeignKeys ){
    FKey *p;
    for(p=sqlite3FkReferences(pTab); p; p=p->pNextTo){
      Table *pFrom = p->pFrom;
      if( pFrom!=pTab ){
        reloadTableSchema(pParse, p->pFrom, pFrom->zName);
      }
    }
  }
#endif

  /* Drop and reload the internal table schema. */
  reloadTableSchema(pParse, pTab, zName);

exit_rename_table:
  sqlite3SrcListDelete(db, pSrc);
  sqlite3DbFree(db, zName);
  db->flags = savedDbFlags;
}
Esempio n. 19
0
/*
** Load the content of the sqlite_stat1 and sqlite_stat2 tables. The
** contents of sqlite_stat1 are used to populate the Index.aiRowEst[]
** arrays. The contents of sqlite_stat2 are used to populate the
** Index.aSample[] arrays.
**
** If the sqlite_stat1 table is not present in the database, SQLITE_ERROR
** is returned. In this case, even if SQLITE_ENABLE_STAT2 was defined 
** during compilation and the sqlite_stat2 table is present, no data is 
** read from it.
**
** If SQLITE_ENABLE_STAT2 was defined during compilation and the 
** sqlite_stat2 table is not present in the database, SQLITE_ERROR is
** returned. However, in this case, data is read from the sqlite_stat1
** table (if it is present) before returning.
**
** If an OOM error occurs, this function always sets db->mallocFailed.
** This means if the caller does not care about other errors, the return
** code may be ignored.
*/
int sqlite3AnalysisLoad(sqlite3 *db, int iDb){
  analysisInfo sInfo;
  HashElem *i;
  char *zSql;
  int rc;

  assert( iDb>=0 && iDb<db->nDb );
  assert( db->aDb[iDb].pBt!=0 );

  /* Clear any prior statistics */
  assert( sqlite3SchemaMutexHeld(db, iDb, 0) );
  for(i=sqliteHashFirst(&db->aDb[iDb].pSchema->idxHash);i;i=sqliteHashNext(i)){
    Index *pIdx = (Index *) sqliteHashData(i);
    sqlite3DefaultRowEst(pIdx);
    sqlite3DeleteIndexSamples(db, pIdx);
    pIdx->aSample = 0;
  }

  /* Check to make sure the sqlite_stat1 table exists */
  sInfo.db = db;
  sInfo.zDatabase = db->aDb[iDb].zName;
  if( sqlite3FindTable(db, "sqlite_stat1", sInfo.zDatabase)==0 ){
    return SQLITE_ERROR;
  }

  /* Load new statistics out of the sqlite_stat1 table */
  zSql = sqlite3MPrintf(db, 
      "SELECT tbl, idx, stat FROM %Q.sqlite_stat1", sInfo.zDatabase);
  if( zSql==0 ){
    rc = SQLITE_NOMEM;
  }else{
    rc = sqlite3_exec(db, zSql, analysisLoader, &sInfo, 0);
    sqlite3DbFree(db, zSql);
  }


  /* Load the statistics from the sqlite_stat2 table. */
#ifdef SQLITE_ENABLE_STAT2
  if( rc==SQLITE_OK && !sqlite3FindTable(db, "sqlite_stat2", sInfo.zDatabase) ){
    rc = SQLITE_ERROR;
  }
  if( rc==SQLITE_OK ){
    sqlite3_stmt *pStmt = 0;

    zSql = sqlite3MPrintf(db, 
        "SELECT idx,sampleno,sample FROM %Q.sqlite_stat2", sInfo.zDatabase);
    if( !zSql ){
      rc = SQLITE_NOMEM;
    }else{
      rc = sqlite3_prepare(db, zSql, -1, &pStmt, 0);
      sqlite3DbFree(db, zSql);
    }

    if( rc==SQLITE_OK ){
      while( sqlite3_step(pStmt)==SQLITE_ROW ){
        char *zIndex;   /* Index name */
        Index *pIdx;    /* Pointer to the index object */

        zIndex = (char *)sqlite3_column_text(pStmt, 0);
        pIdx = zIndex ? sqlite3FindIndex(db, zIndex, sInfo.zDatabase) : 0;
        if( pIdx ){
          int iSample = sqlite3_column_int(pStmt, 1);
          if( iSample<SQLITE_INDEX_SAMPLES && iSample>=0 ){
            int eType = sqlite3_column_type(pStmt, 2);

            if( pIdx->aSample==0 ){
              static const int sz = sizeof(IndexSample)*SQLITE_INDEX_SAMPLES;
              pIdx->aSample = (IndexSample *)sqlite3DbMallocRaw(0, sz);
              if( pIdx->aSample==0 ){
                db->mallocFailed = 1;
                break;
              }
	      memset(pIdx->aSample, 0, sz);
            }

            assert( pIdx->aSample );
            {
              IndexSample *pSample = &pIdx->aSample[iSample];
              pSample->eType = (u8)eType;
              if( eType==SQLITE_INTEGER || eType==SQLITE_FLOAT ){
                pSample->u.r = sqlite3_column_double(pStmt, 2);
              }else if( eType==SQLITE_TEXT || eType==SQLITE_BLOB ){
                const char *z = (const char *)(
                    (eType==SQLITE_BLOB) ?
                    sqlite3_column_blob(pStmt, 2):
                    sqlite3_column_text(pStmt, 2)
                );
                int n = sqlite3_column_bytes(pStmt, 2);
                if( n>24 ){
                  n = 24;
                }
                pSample->nByte = (u8)n;
                if( n < 1){
                  pSample->u.z = 0;
                }else{
                  pSample->u.z = sqlite3DbStrNDup(0, z, n);
                  if( pSample->u.z==0 ){
                    db->mallocFailed = 1;
                    break;
                  }
                }
              }
            }
          }
        }
      }
      rc = sqlite3_finalize(pStmt);
    }
  }
#endif

  if( rc==SQLITE_NOMEM ){
    db->mallocFailed = 1;
  }
  return rc;
}
Esempio n. 20
0
/*
** This function is called after an "ALTER TABLE ... ADD" statement
** has been parsed. Argument pColDef contains the text of the new
** column definition.
**
** The Table structure pParse->pNewTable was extended to include
** the new column during parsing.
*/
void sqlite3AlterFinishAddColumn(Parse *pParse, Token *pColDef){
  Table *pNew;              /* Copy of pParse->pNewTable */
  Table *pTab;              /* Table being altered */
  int iDb;                  /* Database number */
  const char *zDb;          /* Database name */
  const char *zTab;         /* Table name */
  char *zCol;               /* Null-terminated column definition */
  Column *pCol;             /* The new column */
  Expr *pDflt;              /* Default value for the new column */
  sqlite3 *db;              /* The database connection; */
  Vdbe *v = pParse->pVdbe;  /* The prepared statement under construction */

  db = pParse->db;
  if( pParse->nErr || db->mallocFailed ) return;
  assert( v!=0 );
  pNew = pParse->pNewTable;
  assert( pNew );

  assert( sqlite3BtreeHoldsAllMutexes(db) );
  iDb = sqlite3SchemaToIndex(db, pNew->pSchema);
  zDb = db->aDb[iDb].zName;
  zTab = &pNew->zName[16];  /* Skip the "sqlite_altertab_" prefix on the name */
  pCol = &pNew->aCol[pNew->nCol-1];
  pDflt = pCol->pDflt;
  pTab = sqlite3FindTable(db, zTab, zDb);
  assert( pTab );

#ifndef SQLITE_OMIT_AUTHORIZATION
  /* Invoke the authorization callback. */
  if( sqlite3AuthCheck(pParse, SQLITE_ALTER_TABLE, zDb, pTab->zName, 0) ){
    return;
  }
#endif

  /* If the default value for the new column was specified with a
  ** literal NULL, then set pDflt to 0. This simplifies checking
  ** for an SQL NULL default below.
  */
  if( pDflt && pDflt->op==TK_NULL ){
    pDflt = 0;
  }

  /* Check that the new column is not specified as PRIMARY KEY or UNIQUE.
  ** If there is a NOT NULL constraint, then the default value for the
  ** column must not be NULL.
  */
  if( pCol->colFlags & COLFLAG_PRIMKEY ){
    sqlite3ErrorMsg(pParse, "Cannot add a PRIMARY KEY column");
    return;
  }
  if( pNew->pIndex ){
    sqlite3ErrorMsg(pParse, "Cannot add a UNIQUE column");
    return;
  }
  if( (db->flags&SQLITE_ForeignKeys) && pNew->pFKey && pDflt ){
    sqlite3ErrorMsg(pParse,
        "Cannot add a REFERENCES column with non-NULL default value");
    return;
  }
  if( pCol->notNull && !pDflt ){
    sqlite3ErrorMsg(pParse,
        "Cannot add a NOT NULL column with default value NULL");
    return;
  }

  /* Ensure the default expression is something that sqlite3ValueFromExpr()
  ** can handle (i.e. not CURRENT_TIME etc.)
  */
  if( pDflt ){
    sqlite3_value *pVal = 0;
    int rc;
    rc = sqlite3ValueFromExpr(db, pDflt, SQLITE_UTF8, SQLITE_AFF_BLOB, &pVal);
    assert( rc==SQLITE_OK || rc==SQLITE_NOMEM );
    if( rc!=SQLITE_OK ){
      assert( db->mallocFailed == 1 );
      return;
    }
    if( !pVal ){
      sqlite3ErrorMsg(pParse, "Cannot add a column with non-constant default");
      return;
    }
    sqlite3ValueFree(pVal);
  }

  /* Modify the CREATE TABLE statement. */
  zCol = sqlite3DbStrNDup(db, (char*)pColDef->z, pColDef->n);
  if( zCol ){
    char *zEnd = &zCol[pColDef->n-1];
    int savedDbFlags = db->flags;
    while( zEnd>zCol && (*zEnd==';' || sqlite3Isspace(*zEnd)) ){
      *zEnd-- = '\0';
    }
    db->flags |= SQLITE_PreferBuiltin;
    sqlite3NestedParse(pParse,
        "UPDATE \"%w\".%s SET "
          "sql = substr(sql,1,%d) || ', ' || %Q || substr(sql,%d) "
        "WHERE type = 'table' AND name = %Q",
      zDb, SCHEMA_TABLE(iDb), pNew->addColOffset, zCol, pNew->addColOffset+1,
      zTab
    );
    sqlite3DbFree(db, zCol);
    db->flags = savedDbFlags;
  }

  /* If the default value of the new column is NULL, then the file
  ** format to 2. If the default value of the new column is not NULL,
  ** the file format be 3.  Back when this feature was first added
  ** in 2006, we went to the trouble to upgrade the file format to the
  ** minimum support values.  But 10-years on, we can assume that all
  ** extent versions of SQLite support file-format 4, so we always and
  ** unconditionally upgrade to 4.
  */
  sqlite3VdbeAddOp3(v, OP_SetCookie, iDb, BTREE_FILE_FORMAT,
                    SQLITE_MAX_FILE_FORMAT);

  /* Reload the schema of the modified table. */
  reloadTableSchema(pParse, pTab, pTab->zName);
}
Esempio n. 21
0
/*
** Process a pragma statement.  
**
** Pragmas are of this form:
**
**      PRAGMA [database.]id [= value]
**
** The identifier might also be a string.  The value is a string, and
** identifier, or a number.  If minusFlag is true, then the value is
** a number that was preceded by a minus sign.
**
** If the left side is "database.id" then pId1 is the database name
** and pId2 is the id.  If the left side is just "id" then pId1 is the
** id and pId2 is any empty string.
*/
void sqlite3Pragma(
  Parse *pParse, 
  Token *pId1,        /* First part of [database.]id field */
  Token *pId2,        /* Second part of [database.]id field, or NULL */
  Token *pValue,      /* Token for <value>, or NULL */
  int minusFlag       /* True if a '-' sign preceded <value> */
){
  char *zLeft = 0;       /* Nul-terminated UTF-8 string <id> */
  char *zRight = 0;      /* Nul-terminated UTF-8 string <value>, or NULL */
  const char *zDb = 0;   /* The database name */
  Token *pId;            /* Pointer to <id> token */
  int iDb;               /* Database index for <database> */
  sqlite3 *db = pParse->db;
  Db *pDb;
  Vdbe *v = sqlite3GetVdbe(pParse);
  if( v==0 ) return;

  /* Interpret the [database.] part of the pragma statement. iDb is the
  ** index of the database this pragma is being applied to in db.aDb[]. */
  iDb = sqlite3TwoPartName(pParse, pId1, pId2, &pId);
  if( iDb<0 ) return;
  pDb = &db->aDb[iDb];

  zLeft = sqlite3NameFromToken(pId);
  if( !zLeft ) return;
  if( minusFlag ){
    zRight = sqlite3MPrintf("-%T", pValue);
  }else{
    zRight = sqlite3NameFromToken(pValue);
  }

  zDb = ((iDb>0)?pDb->zName:0);
  if( sqlite3AuthCheck(pParse, SQLITE_PRAGMA, zLeft, zRight, zDb) ){
    goto pragma_out;
  }
 
#ifndef SQLITE_OMIT_PAGER_PRAGMAS
  /*
  **  PRAGMA [database.]default_cache_size
  **  PRAGMA [database.]default_cache_size=N
  **
  ** The first form reports the current persistent setting for the
  ** page cache size.  The value returned is the maximum number of
  ** pages in the page cache.  The second form sets both the current
  ** page cache size value and the persistent page cache size value
  ** stored in the database file.
  **
  ** The default cache size is stored in meta-value 2 of page 1 of the
  ** database file.  The cache size is actually the absolute value of
  ** this memory location.  The sign of meta-value 2 determines the
  ** synchronous setting.  A negative value means synchronous is off
  ** and a positive value means synchronous is on.
  */
  if( sqlite3StrICmp(zLeft,"default_cache_size")==0 ){
    static const VdbeOpList getCacheSize[] = {
      { OP_ReadCookie,  0, 2,        0},  /* 0 */
      { OP_AbsValue,    0, 0,        0},
      { OP_Dup,         0, 0,        0},
      { OP_Integer,     0, 0,        0},
      { OP_Ne,          0, 6,        0},
      { OP_Integer,     0, 0,        0},  /* 5 */
      { OP_Callback,    1, 0,        0},
    };
    int addr;
    if( sqlite3ReadSchema(pParse) ) goto pragma_out;
    if( !zRight ){
      sqlite3VdbeSetNumCols(v, 1);
      sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "cache_size", P3_STATIC);
      addr = sqlite3VdbeAddOpList(v, ArraySize(getCacheSize), getCacheSize);
      sqlite3VdbeChangeP1(v, addr, iDb);
      sqlite3VdbeChangeP1(v, addr+5, MAX_PAGES);
    }else{
      int size = atoi(zRight);
      if( size<0 ) size = -size;
      sqlite3BeginWriteOperation(pParse, 0, iDb);
      sqlite3VdbeAddOp(v, OP_Integer, size, 0);
      sqlite3VdbeAddOp(v, OP_ReadCookie, iDb, 2);
      addr = sqlite3VdbeAddOp(v, OP_Integer, 0, 0);
      sqlite3VdbeAddOp(v, OP_Ge, 0, addr+3);
      sqlite3VdbeAddOp(v, OP_Negative, 0, 0);
      sqlite3VdbeAddOp(v, OP_SetCookie, iDb, 2);
      pDb->pSchema->cache_size = size;
      sqlite3BtreeSetCacheSize(pDb->pBt, pDb->pSchema->cache_size);
    }
  }else

  /*
  **  PRAGMA [database.]page_size
  **  PRAGMA [database.]page_size=N
  **
  ** The first form reports the current setting for the
  ** database page size in bytes.  The second form sets the
  ** database page size value.  The value can only be set if
  ** the database has not yet been created.
  */
  if( sqlite3StrICmp(zLeft,"page_size")==0 ){
    Btree *pBt = pDb->pBt;
    if( !zRight ){
      int size = pBt ? sqlite3BtreeGetPageSize(pBt) : 0;
      returnSingleInt(pParse, "page_size", size);
    }else{
      sqlite3BtreeSetPageSize(pBt, atoi(zRight), -1);
    }
  }else
#endif /* SQLITE_OMIT_PAGER_PRAGMAS */

  /*
  **  PRAGMA [database.]auto_vacuum
  **  PRAGMA [database.]auto_vacuum=N
  **
  ** Get or set the (boolean) value of the database 'auto-vacuum' parameter.
  */
#ifndef SQLITE_OMIT_AUTOVACUUM
  if( sqlite3StrICmp(zLeft,"auto_vacuum")==0 ){
    Btree *pBt = pDb->pBt;
    if( !zRight ){
      int auto_vacuum = 
          pBt ? sqlite3BtreeGetAutoVacuum(pBt) : SQLITE_DEFAULT_AUTOVACUUM;
      returnSingleInt(pParse, "auto_vacuum", auto_vacuum);
    }else{
      sqlite3BtreeSetAutoVacuum(pBt, getBoolean(zRight));
    }
  }else
#endif

#ifndef SQLITE_OMIT_PAGER_PRAGMAS
  /*
  **  PRAGMA [database.]cache_size
  **  PRAGMA [database.]cache_size=N
  **
  ** The first form reports the current local setting for the
  ** page cache size.  The local setting can be different from
  ** the persistent cache size value that is stored in the database
  ** file itself.  The value returned is the maximum number of
  ** pages in the page cache.  The second form sets the local
  ** page cache size value.  It does not change the persistent
  ** cache size stored on the disk so the cache size will revert
  ** to its default value when the database is closed and reopened.
  ** N should be a positive integer.
  */
  if( sqlite3StrICmp(zLeft,"cache_size")==0 ){
    if( sqlite3ReadSchema(pParse) ) goto pragma_out;
    if( !zRight ){
      returnSingleInt(pParse, "cache_size", pDb->pSchema->cache_size);
    }else{
      int size = atoi(zRight);
      if( size<0 ) size = -size;
      pDb->pSchema->cache_size = size;
      sqlite3BtreeSetCacheSize(pDb->pBt, pDb->pSchema->cache_size);
    }
  }else

  /*
  **   PRAGMA temp_store
  **   PRAGMA temp_store = "default"|"memory"|"file"
  **
  ** Return or set the local value of the temp_store flag.  Changing
  ** the local value does not make changes to the disk file and the default
  ** value will be restored the next time the database is opened.
  **
  ** Note that it is possible for the library compile-time options to
  ** override this setting
  */
  if( sqlite3StrICmp(zLeft, "temp_store")==0 ){
    if( !zRight ){
      returnSingleInt(pParse, "temp_store", db->temp_store);
    }else{
      changeTempStorage(pParse, zRight);
    }
  }else

  /*
  **   PRAGMA temp_store_directory
  **   PRAGMA temp_store_directory = ""|"directory_name"
  **
  ** Return or set the local value of the temp_store_directory flag.  Changing
  ** the value sets a specific directory to be used for temporary files.
  ** Setting to a null string reverts to the default temporary directory search.
  ** If temporary directory is changed, then invalidateTempStorage.
  **
  */
  if( sqlite3StrICmp(zLeft, "temp_store_directory")==0 ){
    if( !zRight ){
      if( sqlite3_temp_directory ){
        sqlite3VdbeSetNumCols(v, 1);
        sqlite3VdbeSetColName(v, 0, COLNAME_NAME, 
            "temp_store_directory", P3_STATIC);
        sqlite3VdbeOp3(v, OP_String8, 0, 0, sqlite3_temp_directory, 0);
        sqlite3VdbeAddOp(v, OP_Callback, 1, 0);
      }
    }else{
      if( zRight[0] && !sqlite3OsIsDirWritable(zRight) ){
        sqlite3ErrorMsg(pParse, "not a writable directory");
        goto pragma_out;
      }
      if( TEMP_STORE==0
       || (TEMP_STORE==1 && db->temp_store<=1)
       || (TEMP_STORE==2 && db->temp_store==1)
      ){
        invalidateTempStorage(pParse);
      }
      sqliteFree(sqlite3_temp_directory);
      if( zRight[0] ){
        sqlite3_temp_directory = zRight;
        zRight = 0;
      }else{
        sqlite3_temp_directory = 0;
      }
    }
  }else

  /*
  **   PRAGMA [database.]synchronous
  **   PRAGMA [database.]synchronous=OFF|ON|NORMAL|FULL
  **
  ** Return or set the local value of the synchronous flag.  Changing
  ** the local value does not make changes to the disk file and the
  ** default value will be restored the next time the database is
  ** opened.
  */
  if( sqlite3StrICmp(zLeft,"synchronous")==0 ){
    if( sqlite3ReadSchema(pParse) ) goto pragma_out;
    if( !zRight ){
      returnSingleInt(pParse, "synchronous", pDb->safety_level-1);
    }else{
      if( !db->autoCommit ){
        sqlite3ErrorMsg(pParse, 
            "Safety level may not be changed inside a transaction");
      }else{
        pDb->safety_level = getSafetyLevel(zRight)+1;
      }
    }
  }else
#endif /* SQLITE_OMIT_PAGER_PRAGMAS */

#ifndef SQLITE_OMIT_FLAG_PRAGMAS
  if( flagPragma(pParse, zLeft, zRight) ){
    /* The flagPragma() subroutine also generates any necessary code
    ** there is nothing more to do here */
  }else
#endif /* SQLITE_OMIT_FLAG_PRAGMAS */

#ifndef SQLITE_OMIT_SCHEMA_PRAGMAS
  /*
  **   PRAGMA table_info(<table>)
  **
  ** Return a single row for each column of the named table. The columns of
  ** the returned data set are:
  **
  ** cid:        Column id (numbered from left to right, starting at 0)
  ** name:       Column name
  ** type:       Column declaration type.
  ** notnull:    True if 'NOT NULL' is part of column declaration
  ** dflt_value: The default value for the column, if any.
  */
  if( sqlite3StrICmp(zLeft, "table_info")==0 && zRight ){
    Table *pTab;
    if( sqlite3ReadSchema(pParse) ) goto pragma_out;
    pTab = sqlite3FindTable(db, zRight, zDb);
    if( pTab ){
      int i;
      Column *pCol;
      sqlite3VdbeSetNumCols(v, 6);
      sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "cid", P3_STATIC);
      sqlite3VdbeSetColName(v, 1, COLNAME_NAME, "name", P3_STATIC);
      sqlite3VdbeSetColName(v, 2, COLNAME_NAME, "type", P3_STATIC);
      sqlite3VdbeSetColName(v, 3, COLNAME_NAME, "notnull", P3_STATIC);
      sqlite3VdbeSetColName(v, 4, COLNAME_NAME, "dflt_value", P3_STATIC);
      sqlite3VdbeSetColName(v, 5, COLNAME_NAME, "pk", P3_STATIC);
      sqlite3ViewGetColumnNames(pParse, pTab);
      for(i=0, pCol=pTab->aCol; i<pTab->nCol; i++, pCol++){
        sqlite3VdbeAddOp(v, OP_Integer, i, 0);
        sqlite3VdbeOp3(v, OP_String8, 0, 0, pCol->zName, 0);
        sqlite3VdbeOp3(v, OP_String8, 0, 0,
           pCol->zType ? pCol->zType : "numeric", 0);
        sqlite3VdbeAddOp(v, OP_Integer, pCol->notNull, 0);
        sqlite3ExprCode(pParse, pCol->pDflt);
        sqlite3VdbeAddOp(v, OP_Integer, pCol->isPrimKey, 0);
        sqlite3VdbeAddOp(v, OP_Callback, 6, 0);
      }
    }
  }else

  if( sqlite3StrICmp(zLeft, "index_info")==0 && zRight ){
    Index *pIdx;
    Table *pTab;
    if( sqlite3ReadSchema(pParse) ) goto pragma_out;
    pIdx = sqlite3FindIndex(db, zRight, zDb);
    if( pIdx ){
      int i;
      pTab = pIdx->pTable;
      sqlite3VdbeSetNumCols(v, 3);
      sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "seqno", P3_STATIC);
      sqlite3VdbeSetColName(v, 1, COLNAME_NAME, "cid", P3_STATIC);
      sqlite3VdbeSetColName(v, 2, COLNAME_NAME, "name", P3_STATIC);
      for(i=0; i<pIdx->nColumn; i++){
        int cnum = pIdx->aiColumn[i];
        sqlite3VdbeAddOp(v, OP_Integer, i, 0);
        sqlite3VdbeAddOp(v, OP_Integer, cnum, 0);
        assert( pTab->nCol>cnum );
        sqlite3VdbeOp3(v, OP_String8, 0, 0, pTab->aCol[cnum].zName, 0);
        sqlite3VdbeAddOp(v, OP_Callback, 3, 0);
      }
    }
  }else

  if( sqlite3StrICmp(zLeft, "index_list")==0 && zRight ){
    Index *pIdx;
    Table *pTab;
    if( sqlite3ReadSchema(pParse) ) goto pragma_out;
    pTab = sqlite3FindTable(db, zRight, zDb);
    if( pTab ){
      v = sqlite3GetVdbe(pParse);
      pIdx = pTab->pIndex;
      if( pIdx ){
        int i = 0; 
        sqlite3VdbeSetNumCols(v, 3);
        sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "seq", P3_STATIC);
        sqlite3VdbeSetColName(v, 1, COLNAME_NAME, "name", P3_STATIC);
        sqlite3VdbeSetColName(v, 2, COLNAME_NAME, "unique", P3_STATIC);
        while(pIdx){
          sqlite3VdbeAddOp(v, OP_Integer, i, 0);
          sqlite3VdbeOp3(v, OP_String8, 0, 0, pIdx->zName, 0);
          sqlite3VdbeAddOp(v, OP_Integer, pIdx->onError!=OE_None, 0);
          sqlite3VdbeAddOp(v, OP_Callback, 3, 0);
          ++i;
          pIdx = pIdx->pNext;
        }
      }
    }
  }else

  if( sqlite3StrICmp(zLeft, "database_list")==0 ){
    int i;
    if( sqlite3ReadSchema(pParse) ) goto pragma_out;
    sqlite3VdbeSetNumCols(v, 3);
    sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "seq", P3_STATIC);
    sqlite3VdbeSetColName(v, 1, COLNAME_NAME, "name", P3_STATIC);
    sqlite3VdbeSetColName(v, 2, COLNAME_NAME, "file", P3_STATIC);
    for(i=0; i<db->nDb; i++){
      if( db->aDb[i].pBt==0 ) continue;
      assert( db->aDb[i].zName!=0 );
      sqlite3VdbeAddOp(v, OP_Integer, i, 0);
      sqlite3VdbeOp3(v, OP_String8, 0, 0, db->aDb[i].zName, 0);
      sqlite3VdbeOp3(v, OP_String8, 0, 0,
           sqlite3BtreeGetFilename(db->aDb[i].pBt), 0);
      sqlite3VdbeAddOp(v, OP_Callback, 3, 0);
    }
  }else

  if( sqlite3StrICmp(zLeft, "collation_list")==0 ){
    int i = 0;
    HashElem *p;
    sqlite3VdbeSetNumCols(v, 2);
    sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "seq", P3_STATIC);
    sqlite3VdbeSetColName(v, 1, COLNAME_NAME, "name", P3_STATIC);
    for(p=sqliteHashFirst(&db->aCollSeq); p; p=sqliteHashNext(p)){
      CollSeq *pColl = (CollSeq *)sqliteHashData(p);
      sqlite3VdbeAddOp(v, OP_Integer, i++, 0);
      sqlite3VdbeOp3(v, OP_String8, 0, 0, pColl->zName, 0);
      sqlite3VdbeAddOp(v, OP_Callback, 2, 0);
    }
  }else
#endif /* SQLITE_OMIT_SCHEMA_PRAGMAS */

#ifndef SQLITE_OMIT_FOREIGN_KEY
  if( sqlite3StrICmp(zLeft, "foreign_key_list")==0 && zRight ){
    FKey *pFK;
    Table *pTab;
    if( sqlite3ReadSchema(pParse) ) goto pragma_out;
    pTab = sqlite3FindTable(db, zRight, zDb);
    if( pTab ){
      v = sqlite3GetVdbe(pParse);
      pFK = pTab->pFKey;
      if( pFK ){
        int i = 0; 
        sqlite3VdbeSetNumCols(v, 5);
        sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "id", P3_STATIC);
        sqlite3VdbeSetColName(v, 1, COLNAME_NAME, "seq", P3_STATIC);
        sqlite3VdbeSetColName(v, 2, COLNAME_NAME, "table", P3_STATIC);
        sqlite3VdbeSetColName(v, 3, COLNAME_NAME, "from", P3_STATIC);
        sqlite3VdbeSetColName(v, 4, COLNAME_NAME, "to", P3_STATIC);
        while(pFK){
          int j;
          for(j=0; j<pFK->nCol; j++){
            char *zCol = pFK->aCol[j].zCol;
            sqlite3VdbeAddOp(v, OP_Integer, i, 0);
            sqlite3VdbeAddOp(v, OP_Integer, j, 0);
            sqlite3VdbeOp3(v, OP_String8, 0, 0, pFK->zTo, 0);
            sqlite3VdbeOp3(v, OP_String8, 0, 0,
                             pTab->aCol[pFK->aCol[j].iFrom].zName, 0);
            sqlite3VdbeOp3(v, zCol ? OP_String8 : OP_Null, 0, 0, zCol, 0);
            sqlite3VdbeAddOp(v, OP_Callback, 5, 0);
          }
          ++i;
          pFK = pFK->pNextFrom;
        }
      }
    }
  }else
#endif /* !defined(SQLITE_OMIT_FOREIGN_KEY) */

#ifndef NDEBUG
  if( sqlite3StrICmp(zLeft, "parser_trace")==0 ){
    extern void sqlite3ParserTrace(FILE*, char *);
    if( zRight ){
      if( getBoolean(zRight) ){
        sqlite3ParserTrace(stderr, "parser: ");
      }else{
        sqlite3ParserTrace(0, 0);
      }
    }
  }else
#endif

  /* Reinstall the LIKE and GLOB functions.  The variant of LIKE
  ** used will be case sensitive or not depending on the RHS.
  */
  if( sqlite3StrICmp(zLeft, "case_sensitive_like")==0 ){
    if( zRight ){
      sqlite3RegisterLikeFunctions(db, getBoolean(zRight));
    }
  }else

#ifndef SQLITE_OMIT_INTEGRITY_CHECK
  if( sqlite3StrICmp(zLeft, "integrity_check")==0 ){
    int i, j, addr;

    /* Code that appears at the end of the integrity check.  If no error
    ** messages have been generated, output OK.  Otherwise output the
    ** error message
    */
    static const VdbeOpList endCode[] = {
      { OP_MemLoad,     0, 0,        0},
      { OP_Integer,     0, 0,        0},
      { OP_Ne,          0, 0,        0},    /* 2 */
      { OP_String8,     0, 0,        "ok"},
      { OP_Callback,    1, 0,        0},
    };

    /* Initialize the VDBE program */
    if( sqlite3ReadSchema(pParse) ) goto pragma_out;
    sqlite3VdbeSetNumCols(v, 1);
    sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "integrity_check", P3_STATIC);
    sqlite3VdbeAddOp(v, OP_MemInt, 0, 0);  /* Initialize error count to 0 */

    /* Do an integrity check on each database file */
    for(i=0; i<db->nDb; i++){
      HashElem *x;
      Hash *pTbls;
      int cnt = 0;

      if( OMIT_TEMPDB && i==1 ) continue;

      sqlite3CodeVerifySchema(pParse, i);

      /* Do an integrity check of the B-Tree
      */
      pTbls = &db->aDb[i].pSchema->tblHash;
      for(x=sqliteHashFirst(pTbls); x; x=sqliteHashNext(x)){
        Table *pTab = sqliteHashData(x);
        Index *pIdx;
        sqlite3VdbeAddOp(v, OP_Integer, pTab->tnum, 0);
        cnt++;
        for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
          sqlite3VdbeAddOp(v, OP_Integer, pIdx->tnum, 0);
          cnt++;
        }
      }
      assert( cnt>0 );
      sqlite3VdbeAddOp(v, OP_IntegrityCk, cnt, i);
      sqlite3VdbeAddOp(v, OP_Dup, 0, 1);
      addr = sqlite3VdbeOp3(v, OP_String8, 0, 0, "ok", P3_STATIC);
      sqlite3VdbeAddOp(v, OP_Eq, 0, addr+7);
      sqlite3VdbeOp3(v, OP_String8, 0, 0,
         sqlite3MPrintf("*** in database %s ***\n", db->aDb[i].zName),
         P3_DYNAMIC);
      sqlite3VdbeAddOp(v, OP_Pull, 1, 0);
      sqlite3VdbeAddOp(v, OP_Concat, 0, 1);
      sqlite3VdbeAddOp(v, OP_Callback, 1, 0);
      sqlite3VdbeAddOp(v, OP_MemIncr, 1, 0);

      /* Make sure all the indices are constructed correctly.
      */
      sqlite3CodeVerifySchema(pParse, i);
      for(x=sqliteHashFirst(pTbls); x; x=sqliteHashNext(x)){
        Table *pTab = sqliteHashData(x);
        Index *pIdx;
        int loopTop;

        if( pTab->pIndex==0 ) continue;
        sqlite3OpenTableAndIndices(pParse, pTab, 1, OP_OpenRead);
        sqlite3VdbeAddOp(v, OP_MemInt, 0, 1);
        loopTop = sqlite3VdbeAddOp(v, OP_Rewind, 1, 0);
        sqlite3VdbeAddOp(v, OP_MemIncr, 1, 1);
        for(j=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, j++){
          int jmp2;
          static const VdbeOpList idxErr[] = {
            { OP_MemIncr,     1,  0,  0},
            { OP_String8,     0,  0,  "rowid "},
            { OP_Rowid,       1,  0,  0},
            { OP_String8,     0,  0,  " missing from index "},
            { OP_String8,     0,  0,  0},    /* 4 */
            { OP_Concat,      2,  0,  0},
            { OP_Callback,    1,  0,  0},
          };
          sqlite3GenerateIndexKey(v, pIdx, 1);
          jmp2 = sqlite3VdbeAddOp(v, OP_Found, j+2, 0);
          addr = sqlite3VdbeAddOpList(v, ArraySize(idxErr), idxErr);
          sqlite3VdbeChangeP3(v, addr+4, pIdx->zName, P3_STATIC);
          sqlite3VdbeJumpHere(v, jmp2);
        }
        sqlite3VdbeAddOp(v, OP_Next, 1, loopTop+1);
        sqlite3VdbeJumpHere(v, loopTop);
        for(j=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, j++){
          static const VdbeOpList cntIdx[] = {
             { OP_MemInt,       0,  2,  0},
             { OP_Rewind,       0,  0,  0},  /* 1 */
             { OP_MemIncr,      1,  2,  0},
             { OP_Next,         0,  0,  0},  /* 3 */
             { OP_MemLoad,      1,  0,  0},
             { OP_MemLoad,      2,  0,  0},
             { OP_Eq,           0,  0,  0},  /* 6 */
             { OP_MemIncr,      1,  0,  0},
             { OP_String8,      0,  0,  "wrong # of entries in index "},
             { OP_String8,      0,  0,  0},  /* 9 */
             { OP_Concat,       0,  0,  0},
             { OP_Callback,     1,  0,  0},
          };
          if( pIdx->tnum==0 ) continue;
          addr = sqlite3VdbeAddOpList(v, ArraySize(cntIdx), cntIdx);
          sqlite3VdbeChangeP1(v, addr+1, j+2);
          sqlite3VdbeChangeP2(v, addr+1, addr+4);
          sqlite3VdbeChangeP1(v, addr+3, j+2);
          sqlite3VdbeChangeP2(v, addr+3, addr+2);
          sqlite3VdbeJumpHere(v, addr+6);
          sqlite3VdbeChangeP3(v, addr+9, pIdx->zName, P3_STATIC);
        }
      } 
    }
    addr = sqlite3VdbeAddOpList(v, ArraySize(endCode), endCode);
    sqlite3VdbeJumpHere(v, addr+2);
  }else
#endif /* SQLITE_OMIT_INTEGRITY_CHECK */

#ifndef SQLITE_OMIT_UTF16
  /*
  **   PRAGMA encoding
  **   PRAGMA encoding = "utf-8"|"utf-16"|"utf-16le"|"utf-16be"
  **
  ** In it's first form, this pragma returns the encoding of the main
  ** database. If the database is not initialized, it is initialized now.
  **
  ** The second form of this pragma is a no-op if the main database file
  ** has not already been initialized. In this case it sets the default
  ** encoding that will be used for the main database file if a new file
  ** is created. If an existing main database file is opened, then the
  ** default text encoding for the existing database is used.
  ** 
  ** In all cases new databases created using the ATTACH command are
  ** created to use the same default text encoding as the main database. If
  ** the main database has not been initialized and/or created when ATTACH
  ** is executed, this is done before the ATTACH operation.
  **
  ** In the second form this pragma sets the text encoding to be used in
  ** new database files created using this database handle. It is only
  ** useful if invoked immediately after the main database i
  */
  if( sqlite3StrICmp(zLeft, "encoding")==0 ){
    static struct EncName {
      char *zName;
      u8 enc;
    } encnames[] = {
      { "UTF-8",    SQLITE_UTF8        },
      { "UTF8",     SQLITE_UTF8        },
      { "UTF-16le", SQLITE_UTF16LE     },
      { "UTF16le",  SQLITE_UTF16LE     },
      { "UTF-16be", SQLITE_UTF16BE     },
      { "UTF16be",  SQLITE_UTF16BE     },
      { "UTF-16",   0 /* Filled in at run-time */ },
      { "UTF16",    0 /* Filled in at run-time */ },
      { 0, 0 }
    };
    struct EncName *pEnc;
    encnames[6].enc = encnames[7].enc = SQLITE_UTF16NATIVE;
    if( !zRight ){    /* "PRAGMA encoding" */
      if( sqlite3ReadSchema(pParse) ) goto pragma_out;
      sqlite3VdbeSetNumCols(v, 1);
      sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "encoding", P3_STATIC);
      sqlite3VdbeAddOp(v, OP_String8, 0, 0);
      for(pEnc=&encnames[0]; pEnc->zName; pEnc++){
        if( pEnc->enc==ENC(pParse->db) ){
          sqlite3VdbeChangeP3(v, -1, pEnc->zName, P3_STATIC);
          break;
        }
      }
      sqlite3VdbeAddOp(v, OP_Callback, 1, 0);
    }else{                        /* "PRAGMA encoding = XXX" */
      /* Only change the value of sqlite.enc if the database handle is not
      ** initialized. If the main database exists, the new sqlite.enc value
      ** will be overwritten when the schema is next loaded. If it does not
      ** already exists, it will be created to use the new encoding value.
      */
      if( 
        !(DbHasProperty(db, 0, DB_SchemaLoaded)) || 
        DbHasProperty(db, 0, DB_Empty) 
      ){
        for(pEnc=&encnames[0]; pEnc->zName; pEnc++){
          if( 0==sqlite3StrICmp(zRight, pEnc->zName) ){
            ENC(pParse->db) = pEnc->enc;
            break;
          }
        }
        if( !pEnc->zName ){
          sqlite3ErrorMsg(pParse, "unsupported encoding: %s", zRight);
        }
      }
    }
  }else
#endif /* SQLITE_OMIT_UTF16 */

#ifndef SQLITE_OMIT_SCHEMA_VERSION_PRAGMAS
  /*
  **   PRAGMA [database.]schema_version
  **   PRAGMA [database.]schema_version = <integer>
  **
  **   PRAGMA [database.]user_version
  **   PRAGMA [database.]user_version = <integer>
  **
  ** The pragma's schema_version and user_version are used to set or get
  ** the value of the schema-version and user-version, respectively. Both
  ** the schema-version and the user-version are 32-bit signed integers
  ** stored in the database header.
  **
  ** The schema-cookie is usually only manipulated internally by SQLite. It
  ** is incremented by SQLite whenever the database schema is modified (by
  ** creating or dropping a table or index). The schema version is used by
  ** SQLite each time a query is executed to ensure that the internal cache
  ** of the schema used when compiling the SQL query matches the schema of
  ** the database against which the compiled query is actually executed.
  ** Subverting this mechanism by using "PRAGMA schema_version" to modify
  ** the schema-version is potentially dangerous and may lead to program
  ** crashes or database corruption. Use with caution!
  **
  ** The user-version is not used internally by SQLite. It may be used by
  ** applications for any purpose.
  */
  if( sqlite3StrICmp(zLeft, "schema_version")==0 ||
      sqlite3StrICmp(zLeft, "user_version")==0 ){

    int iCookie;   /* Cookie index. 0 for schema-cookie, 6 for user-cookie. */
    if( zLeft[0]=='s' || zLeft[0]=='S' ){
      iCookie = 0;
    }else{
      iCookie = 5;
    }

    if( zRight ){
      /* Write the specified cookie value */
      static const VdbeOpList setCookie[] = {
        { OP_Transaction,    0,  1,  0},    /* 0 */
        { OP_Integer,        0,  0,  0},    /* 1 */
        { OP_SetCookie,      0,  0,  0},    /* 2 */
      };
      int addr = sqlite3VdbeAddOpList(v, ArraySize(setCookie), setCookie);
      sqlite3VdbeChangeP1(v, addr, iDb);
      sqlite3VdbeChangeP1(v, addr+1, atoi(zRight));
      sqlite3VdbeChangeP1(v, addr+2, iDb);
      sqlite3VdbeChangeP2(v, addr+2, iCookie);
    }else{
      /* Read the specified cookie value */
      static const VdbeOpList readCookie[] = {
        { OP_ReadCookie,      0,  0,  0},    /* 0 */
        { OP_Callback,        1,  0,  0}
      };
      int addr = sqlite3VdbeAddOpList(v, ArraySize(readCookie), readCookie);
      sqlite3VdbeChangeP1(v, addr, iDb);
      sqlite3VdbeChangeP2(v, addr, iCookie);
      sqlite3VdbeSetNumCols(v, 1);
    }
  }
#endif /* SQLITE_OMIT_SCHEMA_VERSION_PRAGMAS */

#if defined(SQLITE_DEBUG) || defined(SQLITE_TEST)
  /*
  ** Report the current state of file logs for all databases
  */
  if( sqlite3StrICmp(zLeft, "lock_status")==0 ){
    static const char *const azLockName[] = {
      "unlocked", "shared", "reserved", "pending", "exclusive"
    };
    int i;
    Vdbe *v = sqlite3GetVdbe(pParse);
    sqlite3VdbeSetNumCols(v, 2);
    sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "database", P3_STATIC);
    sqlite3VdbeSetColName(v, 1, COLNAME_NAME, "status", P3_STATIC);
    for(i=0; i<db->nDb; i++){
      Btree *pBt;
      Pager *pPager;
      if( db->aDb[i].zName==0 ) continue;
      sqlite3VdbeOp3(v, OP_String8, 0, 0, db->aDb[i].zName, P3_STATIC);
      pBt = db->aDb[i].pBt;
      if( pBt==0 || (pPager = sqlite3BtreePager(pBt))==0 ){
        sqlite3VdbeOp3(v, OP_String8, 0, 0, "closed", P3_STATIC);
      }else{
        int j = sqlite3pager_lockstate(pPager);
        sqlite3VdbeOp3(v, OP_String8, 0, 0, 
            (j>=0 && j<=4) ? azLockName[j] : "unknown", P3_STATIC);
      }
      sqlite3VdbeAddOp(v, OP_Callback, 2, 0);
    }
  }else
#endif

#ifdef SQLITE_SSE
  /*
  ** Check to see if the sqlite_statements table exists.  Create it
  ** if it does not.
  */
  if( sqlite3StrICmp(zLeft, "create_sqlite_statement_table")==0 ){
    extern int sqlite3CreateStatementsTable(Parse*);
    sqlite3CreateStatementsTable(pParse);
  }else
#endif

#if SQLITE_HAS_CODEC
  if( sqlite3StrICmp(zLeft, "key")==0 ){
    sqlite3_key(db, zRight, strlen(zRight));
  }else
#endif

  {}

  if( v ){
    /* Code an OP_Expire at the end of each PRAGMA program to cause
    ** the VDBE implementing the pragma to expire. Most (all?) pragmas
    ** are only valid for a single execution.
    */
    sqlite3VdbeAddOp(v, OP_Expire, 1, 0);

    /*
    ** Reset the safety level, in case the fullfsync flag or synchronous
    ** setting changed.
    */
    if( db->autoCommit ){
      sqlite3BtreeSetSafetyLevel(pDb->pBt, pDb->safety_level,
                 (db->flags&SQLITE_FullFSync)!=0);
    }
  }
pragma_out:
  sqliteFree(zLeft);
  sqliteFree(zRight);
}
Esempio n. 22
0
/*
** This function is called after an "ALTER TABLE ... ADD" statement
** has been parsed. Argument pColDef contains the text of the new
** column definition.
**
** The Table structure pParse->pNewTable was extended to include
** the new column during parsing.
*/
void sqlite3AlterFinishAddColumn(Parse *pParse, Token *pColDef){
  Table *pNew;              /* Copy of pParse->pNewTable */
  Table *pTab;              /* Table being altered */
  int iDb;                  /* Database number */
  const char *zDb;          /* Database name */
  const char *zTab;         /* Table name */
  char *zCol;               /* Null-terminated column definition */
  Column *pCol;             /* The new column */
  Expr *pDflt;              /* Default value for the new column */

  if( pParse->nErr ) return;
  pNew = pParse->pNewTable;
  assert( pNew );

  iDb = sqlite3SchemaToIndex(pParse->db, pNew->pSchema);
  zDb = pParse->db->aDb[iDb].zName;
  zTab = pNew->zName;
  pCol = &pNew->aCol[pNew->nCol-1];
  pDflt = pCol->pDflt;
  pTab = sqlite3FindTable(pParse->db, zTab, zDb);
  assert( pTab );

#ifndef SQLITE_OMIT_AUTHORIZATION
  /* Invoke the authorization callback. */
  if( sqlite3AuthCheck(pParse, SQLITE_ALTER_TABLE, zDb, pTab->zName, 0) ){
    return;
  }
#endif

  /* If the default value for the new column was specified with a 
  ** literal NULL, then set pDflt to 0. This simplifies checking
  ** for an SQL NULL default below.
  */
  if( pDflt && pDflt->op==TK_NULL ){
    pDflt = 0;
  }

  /* Check that the new column is not specified as PRIMARY KEY or UNIQUE.
  ** If there is a NOT NULL constraint, then the default value for the
  ** column must not be NULL.
  */
  if( pCol->isPrimKey ){
    sqlite3ErrorMsg(pParse, "Cannot add a PRIMARY KEY column");
    return;
  }
  if( pNew->pIndex ){
    sqlite3ErrorMsg(pParse, "Cannot add a UNIQUE column");
    return;
  }
  if( pCol->notNull && !pDflt ){
    sqlite3ErrorMsg(pParse, 
        "Cannot add a NOT NULL column with default value NULL");
    return;
  }

  /* Ensure the default expression is something that sqlite3ValueFromExpr()
  ** can handle (i.e. not CURRENT_TIME etc.)
  */
  if( pDflt ){
    sqlite3_value *pVal;
    if( sqlite3ValueFromExpr(pDflt, SQLITE_UTF8, SQLITE_AFF_NONE, &pVal) ){
      /* malloc() has failed */
      return;
    }
    if( !pVal ){
      sqlite3ErrorMsg(pParse, "Cannot add a column with non-constant default");
      return;
    }
    sqlite3ValueFree(pVal);
  }

  /* Modify the CREATE TABLE statement. */
  zCol = sqliteStrNDup((char*)pColDef->z, pColDef->n);
  if( zCol ){
    char *zEnd = &zCol[pColDef->n-1];
    while( (zEnd>zCol && *zEnd==';') || isspace(*(unsigned char *)zEnd) ){
      *zEnd-- = '\0';
    }
    sqlite3NestedParse(pParse, 
        "UPDATE %Q.%s SET "
          "sql = substr(sql,1,%d) || ', ' || %Q || substr(sql,%d,length(sql)) "
        "WHERE type = 'table' AND name = %Q", 
      zDb, SCHEMA_TABLE(iDb), pNew->addColOffset, zCol, pNew->addColOffset+1,
      zTab
    );
    sqliteFree(zCol);
  }

  /* If the default value of the new column is NULL, then set the file
  ** format to 2. If the default value of the new column is not NULL,
  ** the file format becomes 3.
  */
  sqlite3MinimumFileFormat(pParse, iDb, pDflt ? 3 : 2);

  /* Reload the schema of the modified table. */
  reloadTableSchema(pParse, pTab, pTab->zName);
}
Esempio n. 23
0
/*
** Generate code to implement the "ALTER TABLE xxx RENAME TO yyy" 
** command. 生成代码来实现“ALTER TABLE xxx重命名yyy”命令。
*/
void sqlite3AlterRenameTable(
  Parse *pParse,            /* Parser context. 语法分析器上下文*/
  SrcList *pSrc,            /* The table to rename. 重命名的表*/
  Token *pName              /* The new table name. 新表名*/
){
  int iDb;                  /* Database that contains the table 包含表的数据库*/
  char *zDb;                /* Name of database iDb 数据库iDb 的名称*/
  Table *pTab;              /* Table being renamed 正在重命名的表*/
  char *zName = 0;          /* NULL-terminated version of pName  pName的空值终止版本*/ 
  sqlite3 *db = pParse->db; /* Database connection 数据库的连接*/
  int nTabName;             /* Number of UTF-8 characters in zTabName 在 zTabName里的UTF-8类型的数目*/
  const char *zTabName;     /* Original name of the table 最初的数据库名称*/
  Vdbe *v;
#ifndef SQLITE_OMIT_TRIGGER
  char *zWhere = 0;         /* Where clause to locate temp triggers Where 子句位于temp触发器*/
#endif
  VTable *pVTab = 0;        /* Non-zero if this is a v-tab with an xRename() 如果是 一个v-tab 和一个xRename() ,则为零*/
  int savedDbFlags;         /* Saved value of db->flags db->flags的保留值*/

  savedDbFlags = db->flags;  
  if( NEVER(db->mallocFailed) ) goto exit_rename_table;
  assert( pSrc->nSrc==1 );
  assert( sqlite3BtreeHoldsAllMutexes(pParse->db) );

  pTab = sqlite3LocateTable(pParse, 0, pSrc->a[0].zName, pSrc->a[0].zDatabase);
  if( !pTab ) goto exit_rename_table;
  iDb = sqlite3SchemaToIndex(pParse->db, pTab->pSchema);
  zDb = db->aDb[iDb].zName;
  db->flags |= SQLITE_PreferBuiltin;

  /* Get a NULL terminated version of the new table name. 得到一个空终止版本的新表的名称。*/
  zName = sqlite3NameFromToken(db, pName);
  if( !zName ) goto exit_rename_table;

  /* Check that a table or index named 'zName' does not already exist
  ** in database iDb. If so, this is an error.检查一个表或索引名叫“zName”不存在数据库iDb。
  如果是这样,这是一个错误。
  */
  if( sqlite3FindTable(db, zName, zDb) || sqlite3FindIndex(db, zName, zDb) ){
    sqlite3ErrorMsg(pParse, 
        "there is already another table or index with this name: %s", zName);
    goto exit_rename_table;
  }

  /* Make sure it is not a system table being altered, or a reserved name
  ** that the table is being renamed to.
  确保它不是一个正在被修改的系统表或者一个正在被重命名的保留的名称表
  */
  if( SQLITE_OK!=isSystemTable(pParse, pTab->zName) ){
    goto exit_rename_table;
  }
  if( SQLITE_OK!=sqlite3CheckObjectName(pParse, zName) ){ goto
    exit_rename_table;
  }

#ifndef SQLITE_OMIT_VIEW
  if( pTab->pSelect ){
    sqlite3ErrorMsg(pParse, "view %s may not be altered", pTab->zName);
    goto exit_rename_table;
  }
#endif

#ifndef SQLITE_OMIT_AUTHORIZATION
  /* Invoke the authorization callback. 调用授权回调。*/
  if( sqlite3AuthCheck(pParse, SQLITE_ALTER_TABLE, zDb, pTab->zName, 0) ){
    goto exit_rename_table;
  }
#endif

#ifndef SQLITE_OMIT_VIRTUALTABLE
  if( sqlite3ViewGetColumnNames(pParse, pTab) ){
    goto exit_rename_table;
  }
  if( IsVirtual(pTab) ){
    pVTab = sqlite3GetVTable(db, pTab);
    if( pVTab->pVtab->pModule->xRename==0 ){
      pVTab = 0;
    }
  }
#endif

  /* Begin a transaction and code the VerifyCookie for database iDb. 
  ** Then modify the schema cookie (since the ALTER TABLE modifies the
  ** schema). Open a statement transaction if the table is a virtual
  ** table.
  对于iDb数据库开始一个事务和代码的VerifyCookie。
然后修改模式cookie(因为ALTER TABLE修改模式)。
如果表是一个虚拟表打开一个声明事务。
  */
  v = sqlite3GetVdbe(pParse);
  if( v==0 ){
    goto exit_rename_table;
  }
  sqlite3BeginWriteOperation(pParse, pVTab!=0, iDb);
  sqlite3ChangeCookie(pParse, iDb);

  /* If this is a virtual table, invoke the xRename() function if
  ** one is defined. The xRename() callback will modify the names
  ** of any resources used by the v-table implementation (including other
  ** SQLite tables) that are identified by the name of the virtual table.、
  如果这是一个虚拟表,调用xRename()函数如果一个定义。
  xRename()回调将修改使用v-table实现的任何资源的名字(包括其他SQLite表),
  这个v-table实现是确定的虚拟表的名称。
  */
#ifndef SQLITE_OMIT_VIRTUALTABLE
  if( pVTab ){
    int i = ++pParse->nMem;
    sqlite3VdbeAddOp4(v, OP_String8, 0, i, 0, zName, 0);
    sqlite3VdbeAddOp4(v, OP_VRename, i, 0, 0,(const char*)pVTab, P4_VTAB);
    sqlite3MayAbort(pParse);
  }
#endif

  /* figure out how many UTF-8 characters are in zName 算出在zName里有多少utf - 8字符*/
  zTabName = pTab->zName;
  nTabName = sqlite3Utf8CharLen(zTabName, -1);

#if !defined(SQLITE_OMIT_FOREIGN_KEY) && !defined(SQLITE_OMIT_TRIGGER)
  if( db->flags&SQLITE_ForeignKeys ){
    /* If foreign-key support is enabled, rewrite the CREATE TABLE 
    ** statements corresponding to all child tables of foreign key constraints
    ** for which the renamed table is the parent table. 
    如果启用了外键的支持,重写CREATE TABLE语句对应的所有子表的外键约束重命名表的父表。*/
    if( (zWhere=whereForeignKeys(pParse, pTab))!=0 ){
      sqlite3NestedParse(pParse, 
          "UPDATE \"%w\".%s SET "
              "sql = sqlite_rename_parent(sql, %Q, %Q) "
              "WHERE %s;", zDb, SCHEMA_TABLE(iDb), zTabName, zName, zWhere);
      sqlite3DbFree(db, zWhere);
    }
  }
#endif

  /* Modify the sqlite_master table to use the new table name. 修改sqlite_master表来使用新的表名。*/
  sqlite3NestedParse(pParse,
      "UPDATE %Q.%s SET "
#ifdef SQLITE_OMIT_TRIGGER
          "sql = sqlite_rename_table(sql, %Q), "
#else
          "sql = CASE "
            "WHEN type = 'trigger' THEN sqlite_rename_trigger(sql, %Q)"
            "ELSE sqlite_rename_table(sql, %Q) END, "
#endif
          "tbl_name = %Q, "
          "name = CASE "
            "WHEN type='table' THEN %Q "
            "WHEN name LIKE 'sqlite_autoindex%%' AND type='index' THEN "
             "'sqlite_autoindex_' || %Q || substr(name,%d+18) "
            "ELSE name END "
      "WHERE tbl_name=%Q COLLATE nocase AND "
          "(type='table' OR type='index' OR type='trigger');", 
      zDb, SCHEMA_TABLE(iDb), zName, zName, zName, 
#ifndef SQLITE_OMIT_TRIGGER
      zName,
#endif
      zName, nTabName, zTabName
  );

#ifndef SQLITE_OMIT_AUTOINCREMENT
  /* If the sqlite_sequence table exists in this database, then update 
  ** it with the new table name.
  如果sqlite_sequence表存在于这个数据库中,那么用新表的名称更新它
  */
  if( sqlite3FindTable(db, "sqlite_sequence", zDb) ){
    sqlite3NestedParse(pParse,
        "UPDATE \"%w\".sqlite_sequence set name = %Q WHERE name = %Q",
        zDb, zName, pTab->zName);
  }
#endif

#ifndef SQLITE_OMIT_TRIGGER
  /* If there are TEMP triggers on this table, modify the sqlite_temp_master
  ** table. Don't do this if the table being ALTERed is itself located in
  ** the temp database.
  如果在这个表上有临时触发器,修改sqlite_temp_master表,
  如果表被修改本身就是位于临时数据库,不要做这些。
  */
  if( (zWhere=whereTempTriggers(pParse, pTab))!=0 ){
    sqlite3NestedParse(pParse, 
        "UPDATE sqlite_temp_master SET "
            "sql = sqlite_rename_trigger(sql, %Q), "
            "tbl_name = %Q "
            "WHERE %s;", zName, zName, zWhere);
    sqlite3DbFree(db, zWhere);
  }
#endif

#if !defined(SQLITE_OMIT_FOREIGN_KEY) && !defined(SQLITE_OMIT_TRIGGER)
  if( db->flags&SQLITE_ForeignKeys ){
    FKey *p;
    for(p=sqlite3FkReferences(pTab); p; p=p->pNextTo){
      Table *pFrom = p->pFrom;
      if( pFrom!=pTab ){
        reloadTableSchema(pParse, p->pFrom, pFrom->zName);
      }
    }
  }
#endif

  /* Drop and reload the internal table schema. 删除和重新加载内部表模式。*/
  reloadTableSchema(pParse, pTab, zName);

exit_rename_table:
  sqlite3SrcListDelete(db, pSrc);
  sqlite3DbFree(db, zName);
  db->flags = savedDbFlags;
}
Esempio n. 24
0
/*
** Generate code to implement the "ALTER TABLE xxx RENAME TO yyy" 
** command. 
*/
void sqlite3AlterRenameTable(
  Parse *pParse,            /* Parser context. */
  SrcList *pSrc,            /* The table to rename. */
  Token *pName              /* The new table name. */
){
  int iDb;                  /* Database that contains the table */
  char *zDb;                /* Name of database iDb */
  Table *pTab;              /* Table being renamed */
  char *zName = 0;          /* NULL-terminated version of pName */ 
  sqlite3 *db = pParse->db; /* Database connection */
  int nTabName;             /* Number of UTF-8 characters in zTabName */
  const char *zTabName;     /* Original name of the table */
  Vdbe *v;
#ifndef SQLITE_OMIT_TRIGGER
  char *zWhere = 0;         /* Where clause to locate temp triggers */
#endif
  int isVirtualRename = 0;  /* True if this is a v-table with an xRename() */
  
  if( sqlite3MallocFailed() ) goto exit_rename_table;
  assert( pSrc->nSrc==1 );

  pTab = sqlite3LocateTable(pParse, pSrc->a[0].zName, pSrc->a[0].zDatabase);
  if( !pTab ) goto exit_rename_table;
  iDb = sqlite3SchemaToIndex(pParse->db, pTab->pSchema);
  zDb = db->aDb[iDb].zName;

  /* Get a NULL terminated version of the new table name. */
  zName = sqlite3NameFromToken(pName);
  if( !zName ) goto exit_rename_table;

  /* Check that a table or index named 'zName' does not already exist
  ** in database iDb. If so, this is an error.
  */
  if( sqlite3FindTable(db, zName, zDb) || sqlite3FindIndex(db, zName, zDb) ){
    sqlite3ErrorMsg(pParse, 
        "there is already another table or index with this name: %s", zName);
    goto exit_rename_table;
  }

  /* Make sure it is not a system table being altered, or a reserved name
  ** that the table is being renamed to.
  */
  if( strlen(pTab->zName)>6 && 0==sqlite3StrNICmp(pTab->zName, "sqlite_", 7) ){
    sqlite3ErrorMsg(pParse, "table %s may not be altered", pTab->zName);
    goto exit_rename_table;
  }
  if( SQLITE_OK!=sqlite3CheckObjectName(pParse, zName) ){
    goto exit_rename_table;
  }

#ifndef SQLITE_OMIT_AUTHORIZATION
  /* Invoke the authorization callback. */
  if( sqlite3AuthCheck(pParse, SQLITE_ALTER_TABLE, zDb, pTab->zName, 0) ){
    goto exit_rename_table;
  }
#endif

#ifndef SQLITE_OMIT_VIRTUALTABLE
  if( sqlite3ViewGetColumnNames(pParse, pTab) ){
    goto exit_rename_table;
  }
  if( IsVirtual(pTab) && pTab->pMod->pModule->xRename ){
    isVirtualRename = 1;
  }
#endif

  /* Begin a transaction and code the VerifyCookie for database iDb. 
  ** Then modify the schema cookie (since the ALTER TABLE modifies the
  ** schema). Open a statement transaction if the table is a virtual
  ** table.
  */
  v = sqlite3GetVdbe(pParse);
  if( v==0 ){
    goto exit_rename_table;
  }
  sqlite3BeginWriteOperation(pParse, isVirtualRename, iDb);
  sqlite3ChangeCookie(db, v, iDb);

  /* If this is a virtual table, invoke the xRename() function if
  ** one is defined. The xRename() callback will modify the names
  ** of any resources used by the v-table implementation (including other
  ** SQLite tables) that are identified by the name of the virtual table.
  */
#ifndef SQLITE_OMIT_VIRTUALTABLE
  if( isVirtualRename ){
    sqlite3VdbeOp3(v, OP_String8, 0, 0, zName, 0);
    sqlite3VdbeOp3(v, OP_VRename, 0, 0, (const char*)pTab->pVtab, P3_VTAB);
  }
#endif

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

  /* Modify the sqlite_master table to use the new table name. */
  sqlite3NestedParse(pParse,
      "UPDATE %Q.%s SET "
#ifdef SQLITE_OMIT_TRIGGER
          "sql = sqlite_rename_table(sql, %Q), "
#else
          "sql = CASE "
            "WHEN type = 'trigger' THEN sqlite_rename_trigger(sql, %Q)"
            "ELSE sqlite_rename_table(sql, %Q) END, "
#endif
          "tbl_name = %Q, "
          "name = CASE "
            "WHEN type='table' THEN %Q "
            "WHEN name LIKE 'sqlite_autoindex%%' AND type='index' THEN "
             "'sqlite_autoindex_' || %Q || substr(name,%d+18,10) "
            "ELSE name END "
      "WHERE tbl_name=%Q AND "
          "(type='table' OR type='index' OR type='trigger');", 
      zDb, SCHEMA_TABLE(iDb), zName, zName, zName, 
#ifndef SQLITE_OMIT_TRIGGER
      zName,
#endif
      zName, nTabName, zTabName
  );

#ifndef SQLITE_OMIT_AUTOINCREMENT
  /* If the sqlite_sequence table exists in this database, then update 
  ** it with the new table name.
  */
  if( sqlite3FindTable(db, "sqlite_sequence", zDb) ){
    sqlite3NestedParse(pParse,
        "UPDATE %Q.sqlite_sequence set name = %Q WHERE name = %Q",
        zDb, zName, pTab->zName);
  }
#endif

#ifndef SQLITE_OMIT_TRIGGER
  /* If there are TEMP triggers on this table, modify the sqlite_temp_master
  ** table. Don't do this if the table being ALTERed is itself located in
  ** the temp database.
  */
  if( (zWhere=whereTempTriggers(pParse, pTab))!=0 ){
    sqlite3NestedParse(pParse, 
        "UPDATE sqlite_temp_master SET "
            "sql = sqlite_rename_trigger(sql, %Q), "
            "tbl_name = %Q "
            "WHERE %s;", zName, zName, zWhere);
    sqliteFree(zWhere);
  }
#endif

  /* Drop and reload the internal table schema. */
  reloadTableSchema(pParse, pTab, zName);

exit_rename_table:
  sqlite3SrcListDelete(pSrc);
  sqliteFree(zName);
}
Esempio n. 25
0
/*
** This function is called when inserting, deleting or updating a row of
** table pTab to generate VDBE code to perform foreign key constraint 
** processing for the operation.
**
** For a DELETE operation, parameter regOld is passed the index of the
** first register in an array of (pTab->nCol+1) registers containing the
** rowid of the row being deleted, followed by each of the column values
** of the row being deleted, from left to right. Parameter regNew is passed
** zero in this case.
**
** For an INSERT operation, regOld is passed zero and regNew is passed the
** first register of an array of (pTab->nCol+1) registers containing the new
** row data.
**
** For an UPDATE operation, this function is called twice. Once before
** the original record is deleted from the table using the calling convention
** described for DELETE. Then again after the original record is deleted
** but before the new record is inserted using the INSERT convention. 
*/
void sqlite3FkCheck(
  Parse *pParse,                  /* Parse context */
  Table *pTab,                    /* Row is being deleted from this table */ 
  int regOld,                     /* Previous row data is stored here */
  int regNew                      /* New row data is stored here */
){
  sqlite3 *db = pParse->db;       /* Database handle */
  FKey *pFKey;                    /* Used to iterate through FKs */
  int iDb;                        /* Index of database containing pTab */
  const char *zDb;                /* Name of database containing pTab */
  int isIgnoreErrors = pParse->disableTriggers;

  /* Exactly one of regOld and regNew should be non-zero. */
  assert( (regOld==0)!=(regNew==0) );

  /* If foreign-keys are disabled, this function is a no-op. */
  if( (db->flags&SQLITE_ForeignKeys)==0 ) return;

  iDb = sqlite3SchemaToIndex(db, pTab->pSchema);
  zDb = db->aDb[iDb].zName;

  /* Loop through all the foreign key constraints for which pTab is the
  ** child table (the table that the foreign key definition is part of).  */
  for(pFKey=pTab->pFKey; pFKey; pFKey=pFKey->pNextFrom){
    Table *pTo;                   /* Parent table of foreign key pFKey */
    Index *pIdx = 0;              /* Index on key columns in pTo */
    int *aiFree = 0;
    int *aiCol;
    int iCol;
    int i;
    int isIgnore = 0;

    /* Find the parent table of this foreign key. Also find a unique index 
    ** on the parent key columns in the parent table. If either of these 
    ** schema items cannot be located, set an error in pParse and return 
    ** early.  */
    if( pParse->disableTriggers ){
      pTo = sqlite3FindTable(db, pFKey->zTo, zDb);
    }else{
      pTo = sqlite3LocateTable(pParse, 0, pFKey->zTo, zDb);
    }
    if( !pTo || locateFkeyIndex(pParse, pTo, pFKey, &pIdx, &aiFree) ){
      assert( isIgnoreErrors==0 || (regOld!=0 && regNew==0) );
      if( !isIgnoreErrors || db->mallocFailed ) return;
      if( pTo==0 ){
        /* If isIgnoreErrors is true, then a table is being dropped. In this
        ** case SQLite runs a "DELETE FROM xxx" on the table being dropped
        ** before actually dropping it in order to check FK constraints.
        ** If the parent table of an FK constraint on the current table is
        ** missing, behave as if it is empty. i.e. decrement the relevant
        ** FK counter for each row of the current table with non-NULL keys.
        */
        Vdbe *v = sqlite3GetVdbe(pParse);
        int iJump = sqlite3VdbeCurrentAddr(v) + pFKey->nCol + 1;
        for(i=0; i<pFKey->nCol; i++){
          int iReg = pFKey->aCol[i].iFrom + regOld + 1;
          sqlite3VdbeAddOp2(v, OP_IsNull, iReg, iJump);
        }
        sqlite3VdbeAddOp2(v, OP_FkCounter, pFKey->isDeferred, -1);
      }
      continue;
    }
    assert( pFKey->nCol==1 || (aiFree && pIdx) );

    if( aiFree ){
      aiCol = aiFree;
    }else{
      iCol = pFKey->aCol[0].iFrom;
      aiCol = &iCol;
    }
    for(i=0; i<pFKey->nCol; i++){
      if( aiCol[i]==pTab->iPKey ){
        aiCol[i] = -1;
      }
#ifndef SQLITE_OMIT_AUTHORIZATION
      /* Request permission to read the parent key columns. If the 
      ** authorization callback returns SQLITE_IGNORE, behave as if any
      ** values read from the parent table are NULL. */
      if( db->xAuth ){
        int rcauth;
        char *zCol = pTo->aCol[pIdx ? pIdx->aiColumn[i] : pTo->iPKey].zName;
        rcauth = sqlite3AuthReadCol(pParse, pTo->zName, zCol, iDb);
        isIgnore = (rcauth==SQLITE_IGNORE);
      }
#endif
    }

    /* Take a shared-cache advisory read-lock on the parent table. Allocate 
    ** a cursor to use to search the unique index on the parent key columns 
    ** in the parent table.  */
    sqlite3TableLock(pParse, iDb, pTo->tnum, 0, pTo->zName);
    pParse->nTab++;

    if( regOld!=0 ){
      /* A row is being removed from the child table. Search for the parent.
      ** If the parent does not exist, removing the child row resolves an 
      ** outstanding foreign key constraint violation. */
      fkLookupParent(pParse, iDb, pTo, pIdx, pFKey, aiCol, regOld, -1,isIgnore);
    }
    if( regNew!=0 ){
      /* A row is being added to the child table. If a parent row cannot
      ** be found, adding the child row has violated the FK constraint. */ 
      fkLookupParent(pParse, iDb, pTo, pIdx, pFKey, aiCol, regNew, +1,isIgnore);
    }

    sqlite3DbFree(db, aiFree);
  }

  /* Loop through all the foreign key constraints that refer to this table */
  for(pFKey = sqlite3FkReferences(pTab); pFKey; pFKey=pFKey->pNextTo){
    Index *pIdx = 0;              /* Foreign key index for pFKey */
    SrcList *pSrc;
    int *aiCol = 0;

    if( !pFKey->isDeferred && !pParse->pToplevel && !pParse->isMultiWrite ){
      assert( regOld==0 && regNew!=0 );
      /* Inserting a single row into a parent table cannot cause an immediate
      ** foreign key violation. So do nothing in this case.  */
      continue;
    }

    if( locateFkeyIndex(pParse, pTab, pFKey, &pIdx, &aiCol) ){
      if( !isIgnoreErrors || db->mallocFailed ) return;
      continue;
    }
    assert( aiCol || pFKey->nCol==1 );

    /* Create a SrcList structure containing a single table (the table 
    ** the foreign key that refers to this table is attached to). This
    ** is required for the sqlite3WhereXXX() interface.  */
    pSrc = sqlite3SrcListAppend(db, 0, 0, 0);
    if( pSrc ){
      struct SrcList_item *pItem = pSrc->a;
      pItem->pTab = pFKey->pFrom;
      pItem->zName = pFKey->pFrom->zName;
      pItem->pTab->nRef++;
      pItem->iCursor = pParse->nTab++;
  
      if( regNew!=0 ){
        fkScanChildren(pParse, pSrc, pTab, pIdx, pFKey, aiCol, regNew, -1);
      }
      if( regOld!=0 ){
        /* If there is a RESTRICT action configured for the current operation
        ** on the parent table of this FK, then throw an exception 
        ** immediately if the FK constraint is violated, even if this is a
        ** deferred trigger. That's what RESTRICT means. To defer checking
        ** the constraint, the FK should specify NO ACTION (represented
        ** using OE_None). NO ACTION is the default.  */
        fkScanChildren(pParse, pSrc, pTab, pIdx, pFKey, aiCol, regOld, 1);
      }
      pItem->zName = 0;
      sqlite3SrcListDelete(db, pSrc);
    }
    sqlite3DbFree(db, aiCol);
  }
}
Esempio n. 26
0
int sqlite3_table_column_metadata(
  sqlite3 *db,                /* Connection handle */
  const char *zDbName,        /* Database name or NULL */
  const char *zTableName,     /* Table name */
  const char *zColumnName,    /* Column name */
  char const **pzDataType,    /* OUTPUT: Declared data type */
  char const **pzCollSeq,     /* OUTPUT: Collation sequence name */
  int *pNotNull,              /* OUTPUT: True if NOT NULL constraint exists */
  int *pPrimaryKey,           /* OUTPUT: True if column part of PK */
  int *pAutoinc               /* OUTPUT: True if colums is auto-increment */
){
  int rc;
  char *zErrMsg = 0;
  Table *pTab = 0;
  Column *pCol = 0;
  int iCol;

  char const *zDataType = 0;
  char const *zCollSeq = 0;
  int notnull = 0;
  int primarykey = 0;
  int autoinc = 0;

  /* Ensure the database schema has been loaded */
  if( sqlite3SafetyOn(db) ){
    return SQLITE_MISUSE;
  }
  rc = sqlite3Init(db, &zErrMsg);
  if( SQLITE_OK!=rc ){
    goto error_out;
  }

  /* Locate the table in question */
  pTab = sqlite3FindTable(db, zTableName, zDbName);
  if( !pTab || pTab->pSelect ){
    pTab = 0;
    goto error_out;
  }

  /* Find the column for which info is requested */
  if( sqlite3IsRowid(zColumnName) ){
    iCol = pTab->iPKey;
    if( iCol>=0 ){
      pCol = &pTab->aCol[iCol];
    }
  }else{
    for(iCol=0; iCol<pTab->nCol; iCol++){
      pCol = &pTab->aCol[iCol];
      if( 0==sqlite3StrICmp(pCol->zName, zColumnName) ){
        break;
      }
    }
    if( iCol==pTab->nCol ){
      pTab = 0;
      goto error_out;
    }
  }

  /* The following block stores the meta information that will be returned
  ** to the caller in local variables zDataType, zCollSeq, notnull, primarykey
  ** and autoinc. At this point there are two possibilities:
  ** 
  **     1. The specified column name was rowid", "oid" or "_rowid_" 
  **        and there is no explicitly declared IPK column. 
  **
  **     2. The table is not a view and the column name identified an 
  **        explicitly declared column. Copy meta information from *pCol.
  */ 
  if( pCol ){
    zDataType = pCol->zType;
    zCollSeq = pCol->zColl;
    notnull = (pCol->notNull?1:0);
    primarykey  = (pCol->isPrimKey?1:0);
    autoinc = ((pTab->iPKey==iCol && pTab->autoInc)?1:0);
  }else{
    zDataType = "INTEGER";
    primarykey = 1;
  }
  if( !zCollSeq ){
    zCollSeq = "BINARY";
  }

error_out:
  if( sqlite3SafetyOff(db) ){
    rc = SQLITE_MISUSE;
  }

  /* Whether the function call succeeded or failed, set the output parameters
  ** to whatever their local counterparts contain. If an error did occur,
  ** this has the effect of zeroing all output parameters.
  */
  if( pzDataType ) *pzDataType = zDataType;
  if( pzCollSeq ) *pzCollSeq = zCollSeq;
  if( pNotNull ) *pNotNull = notnull;
  if( pPrimaryKey ) *pPrimaryKey = primarykey;
  if( pAutoinc ) *pAutoinc = autoinc;

  if( SQLITE_OK==rc && !pTab ){
    sqlite3SetString(&zErrMsg, "no such table column: ", zTableName, ".", 
        zColumnName, 0);
    rc = SQLITE_ERROR;
  }
  sqlite3Error(db, rc, (zErrMsg?"%s":0), zErrMsg);
  sqliteFree(zErrMsg);
  return sqlite3ApiExit(db, rc);
}
Esempio n. 27
0
/*
** Generate code to implement the "ALTER TABLE xxx RENAME TO yyy" 
** command. 
*/
void sqlite3AlterRenameTable(
  Parse *pParse,            /* Parser context. */
  SrcList *pSrc,            /* The table to rename. */
  Token *pName              /* The new table name. */
){
  int iDb;                  /* Database that contains the table */
  char *zDb;                /* Name of database iDb */
  Table *pTab;              /* Table being renamed */
  char *zName = 0;          /* NULL-terminated version of pName */ 
  sqlite3 *db = pParse->db; /* Database connection */
  Vdbe *v;
#ifndef SQLITE_OMIT_TRIGGER
  char *zWhere = 0;         /* Where clause to locate temp triggers */
#endif
  
  if( sqlite3_malloc_failed ) goto exit_rename_table;
  assert( pSrc->nSrc==1 );

  pTab = sqlite3LocateTable(pParse, pSrc->a[0].zName, pSrc->a[0].zDatabase);
  if( !pTab ) goto exit_rename_table;
  iDb = pTab->iDb;
  zDb = db->aDb[iDb].zName;

  /* Get a NULL terminated version of the new table name. */
  zName = sqlite3NameFromToken(pName);
  if( !zName ) goto exit_rename_table;

  /* Check that a table or index named 'zName' does not already exist
  ** in database iDb. If so, this is an error.
  */
  if( sqlite3FindTable(db, zName, zDb) || sqlite3FindIndex(db, zName, zDb) ){
    sqlite3ErrorMsg(pParse, 
        "there is already another table or index with this name: %s", zName);
    goto exit_rename_table;
  }

  /* Make sure it is not a system table being altered, or a reserved name
  ** that the table is being renamed to.
  */
  if( strlen(pTab->zName)>6 && 0==sqlite3StrNICmp(pTab->zName, "sqlite_", 7) ){
    sqlite3ErrorMsg(pParse, "table %s may not be altered", pTab->zName);
    goto exit_rename_table;
  }
  if( SQLITE_OK!=sqlite3CheckObjectName(pParse, zName) ){
    goto exit_rename_table;
  }

#ifndef SQLITE_OMIT_AUTHORIZATION
  /* Invoke the authorization callback. */
  if( sqlite3AuthCheck(pParse, SQLITE_ALTER_TABLE, zDb, pTab->zName, 0) ){
    goto exit_rename_table;
  }
#endif

  /* Begin a transaction and code the VerifyCookie for database iDb. 
  ** Then modify the schema cookie (since the ALTER TABLE modifies the
  ** schema).
  */
  v = sqlite3GetVdbe(pParse);
  if( v==0 ){
    goto exit_rename_table;
  }
  sqlite3BeginWriteOperation(pParse, 0, iDb);
  sqlite3ChangeCookie(db, v, iDb);

  /* Modify the sqlite_master table to use the new table name. */
  sqlite3NestedParse(pParse,
      "UPDATE %Q.%s SET "
#ifdef SQLITE_OMIT_TRIGGER
          "sql = sqlite_rename_table(sql, %Q), "
#else
          "sql = CASE "
            "WHEN type = 'trigger' THEN sqlite_rename_trigger(sql, %Q)"
            "ELSE sqlite_rename_table(sql, %Q) END, "
#endif
          "tbl_name = %Q, "
          "name = CASE "
            "WHEN type='table' THEN %Q "
            "WHEN name LIKE 'sqlite_autoindex%%' AND type='index' THEN "
              "'sqlite_autoindex_' || %Q || substr(name, %d+18,10) "
            "ELSE name END "
      "WHERE tbl_name=%Q AND "
          "(type='table' OR type='index' OR type='trigger');", 
      zDb, SCHEMA_TABLE(iDb), zName, zName, zName, 
#ifndef SQLITE_OMIT_TRIGGER
      zName,
#endif
      zName, strlen(pTab->zName), pTab->zName
  );

#ifndef SQLITE_OMIT_AUTOINCREMENT
  /* If the sqlite_sequence table exists in this database, then update 
  ** it with the new table name.
  */
  if( sqlite3FindTable(db, "sqlite_sequence", zDb) ){
    sqlite3NestedParse(pParse,
        "UPDATE %Q.sqlite_sequence set name = %Q WHERE name = %Q",
        zDb, zName, pTab->zName);
  }
#endif

#ifndef SQLITE_OMIT_TRIGGER
  /* If there are TEMP triggers on this table, modify the sqlite_temp_master
  ** table. Don't do this if the table being ALTERed is itself located in
  ** the temp database.
  */
  if( (zWhere=whereTempTriggers(pParse, pTab)) ){
    sqlite3NestedParse(pParse, 
        "UPDATE sqlite_temp_master SET "
            "sql = sqlite_rename_trigger(sql, %Q), "
            "tbl_name = %Q "
            "WHERE %s;", zName, zName, zWhere);
    sqliteFree(zWhere);
  }
#endif

  /* Drop and reload the internal table schema. */
  reloadTableSchema(pParse, pTab, zName);

exit_rename_table:
  sqlite3SrcListDelete(pSrc);
  sqliteFree(zName);
}
Esempio n. 28
0
/*
** Drop a trigger given a pointer to that trigger.  If nested is false,
** then also generate code to remove the trigger from the SQLITE_MASTER
** table.
*/
void sqlite3DropTriggerPtr(Parse *pParse, Trigger *pTrigger, int nested){
  Table   *pTable;
  Vdbe *v;
  sqlite *db = pParse->db;

  assert( pTrigger->iDb<db->nDb );
  pTable = sqlite3FindTable(db,pTrigger->table,db->aDb[pTrigger->iTabDb].zName);
  assert(pTable);
  assert( pTable->iDb==pTrigger->iDb || pTrigger->iDb==1 );
#ifndef SQLITE_OMIT_AUTHORIZATION
  {
    int code = SQLITE_DROP_TRIGGER;
    const char *zDb = db->aDb[pTrigger->iDb].zName;
    const char *zTab = SCHEMA_TABLE(pTrigger->iDb);
    if( pTrigger->iDb==1 ) code = SQLITE_DROP_TEMP_TRIGGER;
    if( sqlite3AuthCheck(pParse, code, pTrigger->name, pTable->zName, zDb) ||
      sqlite3AuthCheck(pParse, SQLITE_DELETE, zTab, 0, zDb) ){
      return;
    }
  }
#endif

  /* Generate code to destroy the database record of the trigger.
  */
  if( pTable!=0 && (v = sqlite3GetVdbe(pParse))!=0 ){
    int base;
    static VdbeOpList dropTrigger[] = {
      { OP_Rewind,     0, ADDR(9),  0},
      { OP_String8,     0, 0,        0}, /* 1 */
      { OP_Column,     0, 1,        0},
      { OP_Ne,         0, ADDR(8),  0},
      { OP_String8,     0, 0,        "trigger"},
      { OP_Column,     0, 0,        0},
      { OP_Ne,         0, ADDR(8),  0},
      { OP_Delete,     0, 0,        0},
      { OP_Next,       0, ADDR(1),  0}, /* 8 */
    };

    sqlite3BeginWriteOperation(pParse, 0, pTrigger->iDb);
    sqlite3OpenMasterTable(v, pTrigger->iDb);
    base = sqlite3VdbeAddOpList(v,  ArraySize(dropTrigger), dropTrigger);
    sqlite3VdbeChangeP3(v, base+1, pTrigger->name, 0);
    sqlite3ChangeCookie(db, v, pTrigger->iDb);
    sqlite3VdbeAddOp(v, OP_Close, 0, 0);
  }

  /*
  ** If this is not an "explain", then delete the trigger structure.
  */
  if( !pParse->explain ){
    const char *zName = pTrigger->name;
    int nName = strlen(zName);
    if( pTable->pTrigger == pTrigger ){
      pTable->pTrigger = pTrigger->pNext;
    }else{
      Trigger *cc = pTable->pTrigger;
      while( cc ){ 
        if( cc->pNext == pTrigger ){
          cc->pNext = cc->pNext->pNext;
          break;
        }
        cc = cc->pNext;
      }
      assert(cc);
    }
    sqlite3HashInsert(&(db->aDb[pTrigger->iDb].trigHash), zName, nName+1, 0);
    sqlite3DeleteTrigger(pTrigger);
  }
}
Esempio n. 29
0
/*
** Return a pointer to the Table structure for the table that a trigger
** is set on.
*/
static Table *tableOfTrigger(sqlite3 *db, Trigger *pTrigger){
  return sqlite3FindTable(db,pTrigger->table,db->aDb[pTrigger->iTabDb].zName);
}