Esempio n. 1
0
/*
** Evaluate a view and store its result in an ephemeral table.  The
** pWhere argument is an optional WHERE clause that restricts the
** set of rows in the view that are to be added to the ephemeral table.
*/
void sqlite3MaterializeView(
  Parse *pParse,       /* Parsing context */
  Table *pView,        /* View definition */
  Expr *pWhere,        /* Optional WHERE clause to be added */
  int iCur             /* Cursor number for ephemerial table */
){
  SelectDest dest;
  Select *pDup;
  sqlite3 *db = pParse->db;

  pDup = sqlite3SelectDup(db, pView->pSelect, 0);
  if( pWhere ){
    SrcList *pFrom;
    
    pWhere = sqlite3ExprDup(db, pWhere, 0);
    pFrom = sqlite3SrcListAppend(db, 0, 0, 0);
    if( pFrom ){
      assert( pFrom->nSrc==1 );
      pFrom->a[0].zAlias = sqlite3DbStrDup(db, pView->zName);
      pFrom->a[0].pSelect = pDup;
      assert( pFrom->a[0].pOn==0 );
      assert( pFrom->a[0].pUsing==0 );
    }else{
      sqlite3SelectDelete(db, pDup);
    }
    pDup = sqlite3SelectNew(pParse, 0, pFrom, pWhere, 0, 0, 0, 0, 0, 0);
    if( pDup ) pDup->selFlags |= SF_Materialize;
  }
  sqlite3SelectDestInit(&dest, SRT_EphemTab, iCur);
  sqlite3Select(pParse, pDup, &dest);
  sqlite3SelectDelete(db, pDup);
}
Esempio n. 2
0
/*
** Build a trigger step out of an INSERT statement.  Return a pointer
** to the new trigger step.
**
** The parser calls this routine when it sees an INSERT inside the
** body of a trigger.
*/
TriggerStep *sqlite3TriggerInsertStep(
  sqlite3 *db,        /* The database connection */
  Token *pTableName,  /* Name of the table into which we insert */
  IdList *pColumn,    /* List of columns in pTableName to insert into */
  ExprList *pEList,   /* The VALUE clause: a list of values to be inserted */
  Select *pSelect,    /* A SELECT statement that supplies values */
  int orconf          /* The conflict algorithm (OE_Abort, OE_Replace, etc.) */
){
  TriggerStep *pTriggerStep;

  assert(pEList == 0 || pSelect == 0);
  assert(pEList != 0 || pSelect != 0 || db->mallocFailed);

  pTriggerStep = (TriggerStep*)sqlite3DbMallocZero(db, sizeof(TriggerStep));
  if( pTriggerStep ){
    pTriggerStep->op = TK_INSERT;
    pTriggerStep->pSelect = pSelect;
    pTriggerStep->target  = *pTableName;
    pTriggerStep->pIdList = pColumn;
    pTriggerStep->pExprList = pEList;
    pTriggerStep->orconf = orconf;
    sqlitePersistTriggerStep(db, pTriggerStep);
  }else{
    sqlite3IdListDelete(pColumn);
    sqlite3ExprListDelete(pEList);
    sqlite3SelectDelete(pSelect);
  }

  return pTriggerStep;
}
Esempio n. 3
0
/*
** Make a copy of all components of the given trigger step.  This has
** the effect of copying all Expr.token.z values into memory obtained
** from sqlite3_malloc().  As initially created, the Expr.token.z values
** all point to the input string that was fed to the parser.  But that
** string is ephemeral - it will go away as soon as the sqlite3_exec()
** call that started the parser exits.  This routine makes a persistent
** copy of all the Expr.token.z strings so that the TriggerStep structure
** will be valid even after the sqlite3_exec() call returns.
*/
static void sqlitePersistTriggerStep(sqlite3 *db, TriggerStep *p){
  if( p->target.z ){
    p->target.z = (u8*)sqlite3DbStrNDup(db, (char*)p->target.z, p->target.n);
    p->target.dyn = 1;
  }
  if( p->pSelect ){
    Select *pNew = sqlite3SelectDup(db, p->pSelect);
    sqlite3SelectDelete(db, p->pSelect);
    p->pSelect = pNew;
  }
  if( p->pWhere ){
    Expr *pNew = sqlite3ExprDup(db, p->pWhere);
    sqlite3ExprDelete(db, p->pWhere);
    p->pWhere = pNew;
  }
  if( p->pExprList ){
    ExprList *pNew = sqlite3ExprListDup(db, p->pExprList);
    sqlite3ExprListDelete(db, p->pExprList);
    p->pExprList = pNew;
  }
  if( p->pIdList ){
    IdList *pNew = sqlite3IdListDup(db, p->pIdList);
    sqlite3IdListDelete(db, p->pIdList);
    p->pIdList = pNew;
  }
}
/*
 ** Build a trigger step out of an INSERT statement.  Return a pointer
 ** to the new trigger step.
 **
 ** The parser calls this routine when it sees an INSERT inside the
 ** body of a trigger.
 */
SQLITE_PRIVATE TriggerStep *sqlite3TriggerInsertStep(
                                                     sqlite3 *db,        /* The database connection */
                                                     Token *pTableName,  /* Name of the table into which we insert */
                                                     IdList *pColumn,    /* List of columns in pTableName to insert into */
                                                     ExprList *pEList,   /* The VALUE clause: a list of values to be inserted */
                                                     Select *pSelect,    /* A SELECT statement that supplies values */
                                                     u8 orconf           /* The conflict algorithm (OE_Abort, OE_Replace, etc.) */
){
    TriggerStep *pTriggerStep;
    
    assert(pEList == 0 || pSelect == 0);
    assert(pEList != 0 || pSelect != 0 || db->mallocFailed);
    
    pTriggerStep = triggerStepAllocate(db, TK_INSERT, pTableName);
    if( pTriggerStep ){
        pTriggerStep->pSelect = sqlite3SelectDup(db, pSelect, EXPRDUP_REDUCE);
        pTriggerStep->pIdList = pColumn;
        pTriggerStep->pExprList = sqlite3ExprListDup(db, pEList, EXPRDUP_REDUCE);
        pTriggerStep->orconf = orconf;
    }else{
        sqlite3IdListDelete(db, pColumn);
    }
    sqlite3ExprListDelete(db, pEList);
    sqlite3SelectDelete(db, pSelect);
    
    return pTriggerStep;
}
Esempio n. 5
0
/*
** Make a copy of all components of the given trigger step.  This has
** the effect of copying all Expr.token.z values into memory obtained
** from sqliteMalloc().  As initially created, the Expr.token.z values
** all point to the input string that was fed to the parser.  But that
** string is ephemeral - it will go away as soon as the sqlite3_exec()
** call that started the parser exits.  This routine makes a persistent
** copy of all the Expr.token.z strings so that the TriggerStep structure
** will be valid even after the sqlite3_exec() call returns.
*/
static void sqlitePersistTriggerStep(TriggerStep *p){
  if( p->target.z ){
    p->target.z = sqliteStrNDup(p->target.z, p->target.n);
    p->target.dyn = 1;
  }
  if( p->pSelect ){
    Select *pNew = sqlite3SelectDup(p->pSelect);
    sqlite3SelectDelete(p->pSelect);
    p->pSelect = pNew;
  }
  if( p->pWhere ){
    Expr *pNew = sqlite3ExprDup(p->pWhere);
    sqlite3ExprDelete(p->pWhere);
    p->pWhere = pNew;
  }
  if( p->pExprList ){
    ExprList *pNew = sqlite3ExprListDup(p->pExprList);
    sqlite3ExprListDelete(p->pExprList);
    p->pExprList = pNew;
  }
  if( p->pIdList ){
    IdList *pNew = sqlite3IdListDup(p->pIdList);
    sqlite3IdListDelete(p->pIdList);
    p->pIdList = pNew;
  }
}
Esempio n. 6
0
/*
** Evaluate a view and store its result in an ephemeral table.  The
** pWhere argument is an optional WHERE clause that restricts the
** set of rows in the view that are to be added to the ephemeral table.
*/
void sqlite3MaterializeView(
  Parse *pParse,       /* Parsing context */
  Table *pView,        /* View definition */
  Expr *pWhere,        /* Optional WHERE clause to be added */
  int iCur             /* Cursor number for ephemerial table */
){
  SelectDest dest;
  Select *pDup;
  sqlite3 *db = pParse->db;

  pDup = sqlite3SelectDup(db, pView->pSelect);
  if( pWhere ){
    SrcList *pFrom;
    Token viewName;
    
    pWhere = sqlite3ExprDup(db, pWhere);
    viewName.z = (u8*)pView->zName;
    viewName.n = (unsigned int)sqlite3Strlen30((const char*)viewName.z);
    pFrom = sqlite3SrcListAppendFromTerm(pParse, 0, 0, 0, &viewName, pDup, 0,0);
    pDup = sqlite3SelectNew(pParse, 0, pFrom, pWhere, 0, 0, 0, 0, 0, 0);
  }
  sqlite3SelectDestInit(&dest, SRT_EphemTab, iCur);
  sqlite3Select(pParse, pDup, &dest);
  sqlite3SelectDelete(db, pDup);
}
Esempio n. 7
0
/*
** Evaluate a view and store its result in an ephemeral table.  The
** pWhere argument is an optional WHERE clause that restricts the
** set of rows in the view that are to be added to the ephemeral table.
*/
void sqlite3MaterializeView(
  Parse *pParse,       /* Parsing context */
  Table *pView,        /* View definition */
  Expr *pWhere,        /* Optional WHERE clause to be added */
  int iCur             /* Cursor number for ephemeral table */
){
  SelectDest dest;
  Select *pSel;
  SrcList *pFrom;
  sqlite3 *db = pParse->db;
  int iDb = sqlite3SchemaToIndex(db, pView->pSchema);
  pWhere = sqlite3ExprDup(db, pWhere, 0);
  pFrom = sqlite3SrcListAppend(db, 0, 0, 0);
  if( pFrom ){
    assert( pFrom->nSrc==1 );
    pFrom->a[0].zName = sqlite3DbStrDup(db, pView->zName);
    pFrom->a[0].zDatabase = sqlite3DbStrDup(db, db->aDb[iDb].zDbSName);
    assert( pFrom->a[0].pOn==0 );
    assert( pFrom->a[0].pUsing==0 );
  }
  pSel = sqlite3SelectNew(pParse, 0, pFrom, pWhere, 0, 0, 0, 
                          SF_IncludeHidden, 0, 0);
  sqlite3SelectDestInit(&dest, SRT_EphemTab, iCur);
  sqlite3Select(pParse, pSel, &dest);
  sqlite3SelectDelete(db, pSel);
}
Esempio n. 8
0
/*
** The second argument is a Trigger structure allocated by the 
** fkActionTrigger() routine. This function deletes the Trigger structure
** and all of its sub-components.
**
** The Trigger structure or any of its sub-components may be allocated from
** the lookaside buffer belonging to database handle dbMem.
*/
static void fkTriggerDelete(sqlite3 *dbMem, Trigger *p){
  if( p ){
    TriggerStep *pStep = p->step_list;
    sqlite3ExprDelete(dbMem, pStep->pWhere);
    sqlite3ExprListDelete(dbMem, pStep->pExprList);
    sqlite3SelectDelete(dbMem, pStep->pSelect);
    sqlite3ExprDelete(dbMem, p->pWhen);
    sqlite3DbFree(dbMem, p);
  }
}
/*
 ** Turn a SELECT statement (that the pSelect parameter points to) into
 ** a trigger step.  Return a pointer to a TriggerStep structure.
 **
 ** The parser calls this routine when it finds a SELECT statement in
 ** body of a TRIGGER.
 */
SQLITE_PRIVATE TriggerStep *sqlite3TriggerSelectStep(sqlite3 *db, Select *pSelect){
    TriggerStep *pTriggerStep = sqlite3DbMallocZero(db, sizeof(TriggerStep));
    if( pTriggerStep==0 ) {
        sqlite3SelectDelete(db, pSelect);
        return 0;
    }
    pTriggerStep->op = TK_SELECT;
    pTriggerStep->pSelect = pSelect;
    pTriggerStep->orconf = OE_Default;
    return pTriggerStep;
}
/*
 ** Delete a linked list of TriggerStep structures.
 */
SQLITE_PRIVATE void sqlite3DeleteTriggerStep(sqlite3 *db, TriggerStep *pTriggerStep){
    while( pTriggerStep ){
        TriggerStep * pTmp = pTriggerStep;
        pTriggerStep = pTriggerStep->pNext;
        
        sqlite3ExprDelete(db, pTmp->pWhere);
        sqlite3ExprListDelete(db, pTmp->pExprList);
        sqlite3SelectDelete(db, pTmp->pSelect);
        sqlite3IdListDelete(db, pTmp->pIdList);
        
        sqlite3DbFree(db, pTmp);
    }
}
Esempio n. 11
0
/*
** Turn a SELECT statement (that the pSelect parameter points to) into
** a trigger step.  Return a pointer to a TriggerStep structure.
**
** The parser calls this routine when it finds a SELECT statement in
** body of a TRIGGER.  
*/
TriggerStep *sqlite3TriggerSelectStep(Select *pSelect){
  TriggerStep *pTriggerStep = sqliteMalloc(sizeof(TriggerStep));
  if( pTriggerStep==0 ) {
    sqlite3SelectDelete(pSelect);
    return 0;
  }

  pTriggerStep->op = TK_SELECT;
  pTriggerStep->pSelect = pSelect;
  pTriggerStep->orconf = OE_Default;
  sqlitePersistTriggerStep(pTriggerStep);

  return pTriggerStep;
}
Esempio n. 12
0
/*
** Delete a linked list of TriggerStep structures.
*/
void sqlite3DeleteTriggerStep(TriggerStep *pTriggerStep){
  while( pTriggerStep ){
    TriggerStep * pTmp = pTriggerStep;
    pTriggerStep = pTriggerStep->pNext;

    if( pTmp->target.dyn ) sqliteFree((char*)pTmp->target.z);
    sqlite3ExprDelete(pTmp->pWhere);
    sqlite3ExprListDelete(pTmp->pExprList);
    sqlite3SelectDelete(pTmp->pSelect);
    sqlite3IdListDelete(pTmp->pIdList);

    sqliteFree(pTmp);
  }
}
Esempio n. 13
0
/*
** Turn a SELECT statement (that the pSelect parameter points to) into
** a trigger step.  Return a pointer to a TriggerStep structure.
**
** The parser calls this routine when it finds a SELECT statement in
** body of a TRIGGER.  
*/
TriggerStep *sqlite3TriggerSelectStep(sqlite3 *db, Select *pSelect){
  TriggerStep *pTriggerStep = (TriggerStep*)sqlite3DbMallocZero(db, sizeof(TriggerStep));
  if( pTriggerStep==0 ) {
    sqlite3SelectDelete(pSelect);
    return 0;
  }

  pTriggerStep->op = TK_SELECT;
  pTriggerStep->pSelect = pSelect;
  pTriggerStep->orconf = OE_Default;
  sqlitePersistTriggerStep(db, pTriggerStep);

  return pTriggerStep;
}
Esempio n. 14
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/*
** Turn a SELECT statement (that the pSelect parameter points to) into
** a trigger step.  Return a pointer to a TriggerStep structure.
**
** The parser calls this routine when it finds a SELECT statement in
** body of a TRIGGER.  
*/
TriggerStep *sqlite3TriggerSelectStep(
  sqlite3 *db,                /* Database connection */
  Select *pSelect,            /* The SELECT statement */
  const char *zStart,         /* Start of SQL text */
  const char *zEnd            /* End of SQL text */
){
  TriggerStep *pTriggerStep = sqlite3DbMallocZero(db, sizeof(TriggerStep));
  if( pTriggerStep==0 ) {
    sqlite3SelectDelete(db, pSelect);
    return 0;
  }
  pTriggerStep->op = TK_SELECT;
  pTriggerStep->pSelect = pSelect;
  pTriggerStep->orconf = OE_Default;
  pTriggerStep->zSpan = triggerSpanDup(db, zStart, zEnd);
  return pTriggerStep;
}
Esempio n. 15
0
/*
** Evaluate a view and store its result in an ephemeral table.  The
** pWhere argument is an optional WHERE clause that restricts the
** set of rows in the view that are to be added to the ephemeral table.
*/
void sqlite3MaterializeView(
  Parse *pParse,       /* Parsing context */
  Select *pView,       /* View definition */
  Expr *pWhere,        /* Optional WHERE clause to be added */
  int iCur             /* Cursor number for ephemerial table */
){
  SelectDest dest;
  Select *pDup;
  sqlite3 *db = pParse->db;

  pDup = sqlite3SelectDup(db, pView);
  if( pWhere ){
    SrcList *pFrom;
    
    pWhere = sqlite3ExprDup(db, pWhere);
    pFrom = sqlite3SrcListAppendFromTerm(pParse, 0, 0, 0, 0, pDup, 0, 0);
    pDup = sqlite3SelectNew(pParse, 0, pFrom, pWhere, 0, 0, 0, 0, 0, 0);
  }
  sqlite3SelectDestInit(&dest, SRT_EphemTab, iCur);
  sqlite3Select(pParse, pDup, &dest, 0, 0, 0);
  sqlite3SelectDelete(db, pDup);
}
Esempio n. 16
0
/*
** Build a trigger step out of an INSERT statement.  Return a pointer
** to the new trigger step.
**
** The parser calls this routine when it sees an INSERT inside the
** body of a trigger.
*/
TriggerStep *sqlite3TriggerInsertStep(
  Parse *pParse,      /* Parser */
  Token *pTableName,  /* Name of the table into which we insert */
  IdList *pColumn,    /* List of columns in pTableName to insert into */
  Select *pSelect,    /* A SELECT statement that supplies values */
  u8 orconf,          /* The conflict algorithm (OE_Abort, OE_Replace, etc.) */
  Upsert *pUpsert,    /* ON CONFLICT clauses for upsert */
  const char *zStart, /* Start of SQL text */
  const char *zEnd    /* End of SQL text */
){
  sqlite3 *db = pParse->db;
  TriggerStep *pTriggerStep;

  assert(pSelect != 0 || db->mallocFailed);

  pTriggerStep = triggerStepAllocate(pParse, TK_INSERT, pTableName,zStart,zEnd);
  if( pTriggerStep ){
    if( IN_RENAME_OBJECT ){
      pTriggerStep->pSelect = pSelect;
      pSelect = 0;
    }else{
      pTriggerStep->pSelect = sqlite3SelectDup(db, pSelect, EXPRDUP_REDUCE);
    }
    pTriggerStep->pIdList = pColumn;
    pTriggerStep->pUpsert = pUpsert;
    pTriggerStep->orconf = orconf;
  }else{
    testcase( pColumn );
    sqlite3IdListDelete(db, pColumn);
    testcase( pUpsert );
    sqlite3UpsertDelete(db, pUpsert);
  }
  sqlite3SelectDelete(db, pSelect);

  return pTriggerStep;
}
Esempio n. 17
0
/*
** Generate code for a DELETE FROM statement.
**
**     DELETE FROM table_wxyz WHERE a<5 AND b NOT NULL;
**                 \________/       \________________/
**                  pTabList              pWhere
*/
void sqlite3DeleteFrom(
  Parse *pParse,         /* The parser context */
  SrcList *pTabList,     /* The table from which we should delete things */
  Expr *pWhere           /* The WHERE clause.  May be null */
){
  Vdbe *v;               /* The virtual database engine */
  Table *pTab;           /* The table from which records will be deleted */
  const char *zDb;       /* Name of database holding pTab */
  int end, addr = 0;     /* A couple addresses of generated code */
  int i;                 /* Loop counter */
  WhereInfo *pWInfo;     /* Information about the WHERE clause */
  Index *pIdx;           /* For looping over indices of the table */
  int iCur;              /* VDBE Cursor number for pTab */
  sqlite3 *db;           /* Main database structure */
  AuthContext sContext;  /* Authorization context */
  int oldIdx = -1;       /* Cursor for the OLD table of AFTER triggers */
  NameContext sNC;       /* Name context to resolve expressions in */

#ifndef SQLITE_OMIT_TRIGGER
  int isView;                  /* True if attempting to delete from a view */
  int triggers_exist = 0;      /* True if any triggers exist */
#endif

  sContext.pParse = 0;
  if( pParse->nErr || sqlite3_malloc_failed ){
    goto delete_from_cleanup;
  }
  db = pParse->db;
  assert( pTabList->nSrc==1 );

  /* Locate the table which we want to delete.  This table has to be
  ** put in an SrcList structure because some of the subroutines we
  ** will be calling are designed to work with multiple tables and expect
  ** an SrcList* parameter instead of just a Table* parameter.
  */
  pTab = sqlite3SrcListLookup(pParse, pTabList);
  if( pTab==0 )  goto delete_from_cleanup;

  /* Figure out if we have any triggers and if the table being
  ** deleted from is a view
  */
#ifndef SQLITE_OMIT_TRIGGER
  triggers_exist = sqlite3TriggersExist(pParse, pTab, TK_DELETE, 0);
  isView = pTab->pSelect!=0;
#else
# define triggers_exist 0
# define isView 0
#endif
#ifdef SQLITE_OMIT_VIEW
# undef isView
# define isView 0
#endif

  if( sqlite3IsReadOnly(pParse, pTab, triggers_exist) ){
    goto delete_from_cleanup;
  }
  assert( pTab->iDb<db->nDb );
  zDb = db->aDb[pTab->iDb].zName;
  if( sqlite3AuthCheck(pParse, SQLITE_DELETE, pTab->zName, 0, zDb) ){
    goto delete_from_cleanup;
  }

  /* If pTab is really a view, make sure it has been initialized.
  */
  if( isView && sqlite3ViewGetColumnNames(pParse, pTab) ){
    goto delete_from_cleanup;
  }

  /* Allocate a cursor used to store the old.* data for a trigger.
  */
  if( triggers_exist ){ 
    oldIdx = pParse->nTab++;
  }

  /* Resolve the column names in the WHERE clause.
  */
  assert( pTabList->nSrc==1 );
  iCur = pTabList->a[0].iCursor = pParse->nTab++;
  memset(&sNC, 0, sizeof(sNC));
  sNC.pParse = pParse;
  sNC.pSrcList = pTabList;
  if( sqlite3ExprResolveNames(&sNC, pWhere) ){
    goto delete_from_cleanup;
  }

  /* Start the view context
  */
  if( isView ){
    sqlite3AuthContextPush(pParse, &sContext, pTab->zName);
  }

  /* Begin generating code.
  */
  v = sqlite3GetVdbe(pParse);
  if( v==0 ){
    goto delete_from_cleanup;
  }
  if( pParse->nested==0 ) sqlite3VdbeCountChanges(v);
  sqlite3BeginWriteOperation(pParse, triggers_exist, pTab->iDb);

  /* If we are trying to delete from a view, construct that view into
  ** a temporary table.
  */
  if( isView ){
    Select *pView = sqlite3SelectDup(pTab->pSelect);
    sqlite3Select(pParse, pView, SRT_TempTable, iCur, 0, 0, 0, 0);
    sqlite3SelectDelete(pView);
  }

  /* Initialize the counter of the number of rows deleted, if
  ** we are counting rows.
  */
  if( db->flags & SQLITE_CountRows ){
    sqlite3VdbeAddOp(v, OP_Integer, 0, 0);
  }

  /* Special case: A DELETE without a WHERE clause deletes everything.
  ** It is easier just to erase the whole table.  Note, however, that
  ** this means that the row change count will be incorrect.
  */
  if( pWhere==0 && !triggers_exist ){
    if( db->flags & SQLITE_CountRows ){
      /* If counting rows deleted, just count the total number of
      ** entries in the table. */
      int endOfLoop = sqlite3VdbeMakeLabel(v);
      int addr;
      if( !isView ){
        sqlite3OpenTableForReading(v, iCur, pTab);
      }
      sqlite3VdbeAddOp(v, OP_Rewind, iCur, sqlite3VdbeCurrentAddr(v)+2);
      addr = sqlite3VdbeAddOp(v, OP_AddImm, 1, 0);
      sqlite3VdbeAddOp(v, OP_Next, iCur, addr);
      sqlite3VdbeResolveLabel(v, endOfLoop);
      sqlite3VdbeAddOp(v, OP_Close, iCur, 0);
    }
    if( !isView ){
      sqlite3VdbeAddOp(v, OP_Clear, pTab->tnum, pTab->iDb);
      for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
        sqlite3VdbeAddOp(v, OP_Clear, pIdx->tnum, pIdx->iDb);
      }
    }
  }

  /* The usual case: There is a WHERE clause so we have to scan through
  ** the table and pick which records to delete.
  */
  else{
    /* Ensure all required collation sequences are available. */
    for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
      if( sqlite3CheckIndexCollSeq(pParse, pIdx) ){
        goto delete_from_cleanup;
      }
    }

    /* Begin the database scan
    */
    pWInfo = sqlite3WhereBegin(pParse, pTabList, pWhere, 0);
    if( pWInfo==0 ) goto delete_from_cleanup;

    /* Remember the rowid of every item to be deleted.
    */
    sqlite3VdbeAddOp(v, OP_Recno, iCur, 0);
    sqlite3VdbeAddOp(v, OP_ListWrite, 0, 0);
    if( db->flags & SQLITE_CountRows ){
      sqlite3VdbeAddOp(v, OP_AddImm, 1, 0);
    }

    /* End the database scan loop.
    */
    sqlite3WhereEnd(pWInfo);

    /* Open the pseudo-table used to store OLD if there are triggers.
    */
    if( triggers_exist ){
      sqlite3VdbeAddOp(v, OP_OpenPseudo, oldIdx, 0);
      sqlite3VdbeAddOp(v, OP_SetNumColumns, oldIdx, pTab->nCol);
    }

    /* Delete every item whose key was written to the list during the
    ** database scan.  We have to delete items after the scan is complete
    ** because deleting an item can change the scan order.
    */
    sqlite3VdbeAddOp(v, OP_ListRewind, 0, 0);
    end = sqlite3VdbeMakeLabel(v);

    /* This is the beginning of the delete loop when there are
    ** row triggers.
    */
    if( triggers_exist ){
      addr = sqlite3VdbeAddOp(v, OP_ListRead, 0, end);
      if( !isView ){
        sqlite3VdbeAddOp(v, OP_Dup, 0, 0);
        sqlite3OpenTableForReading(v, iCur, pTab);
      }
      sqlite3VdbeAddOp(v, OP_MoveGe, iCur, 0);
      sqlite3VdbeAddOp(v, OP_Recno, iCur, 0);
      sqlite3VdbeAddOp(v, OP_RowData, iCur, 0);
      sqlite3VdbeAddOp(v, OP_PutIntKey, oldIdx, 0);
      if( !isView ){
        sqlite3VdbeAddOp(v, OP_Close, iCur, 0);
      }

      (void)sqlite3CodeRowTrigger(pParse, TK_DELETE, 0, TRIGGER_BEFORE, pTab,
          -1, oldIdx, (pParse->trigStack)?pParse->trigStack->orconf:OE_Default,
          addr);
    }

    if( !isView ){
      /* Open cursors for the table we are deleting from and all its
      ** indices.  If there are row triggers, this happens inside the
      ** OP_ListRead loop because the cursor have to all be closed
      ** before the trigger fires.  If there are no row triggers, the
      ** cursors are opened only once on the outside the loop.
      */
      sqlite3OpenTableAndIndices(pParse, pTab, iCur, OP_OpenWrite);

      /* This is the beginning of the delete loop when there are no
      ** row triggers */
      if( !triggers_exist ){ 
        addr = sqlite3VdbeAddOp(v, OP_ListRead, 0, end);
      }

      /* Delete the row */
      sqlite3GenerateRowDelete(db, v, pTab, iCur, pParse->nested==0);
    }

    /* If there are row triggers, close all cursors then invoke
    ** the AFTER triggers
    */
    if( triggers_exist ){
      if( !isView ){
        for(i=1, pIdx=pTab->pIndex; pIdx; i++, pIdx=pIdx->pNext){
          sqlite3VdbeAddOp(v, OP_Close, iCur + i, pIdx->tnum);
        }
        sqlite3VdbeAddOp(v, OP_Close, iCur, 0);
      }
      (void)sqlite3CodeRowTrigger(pParse, TK_DELETE, 0, TRIGGER_AFTER, pTab, -1,
          oldIdx, (pParse->trigStack)?pParse->trigStack->orconf:OE_Default,
          addr);
    }

    /* End of the delete loop */
    sqlite3VdbeAddOp(v, OP_Goto, 0, addr);
    sqlite3VdbeResolveLabel(v, end);
    sqlite3VdbeAddOp(v, OP_ListReset, 0, 0);

    /* Close the cursors after the loop if there are no row triggers */
    if( !triggers_exist ){
      for(i=1, pIdx=pTab->pIndex; pIdx; i++, pIdx=pIdx->pNext){
        sqlite3VdbeAddOp(v, OP_Close, iCur + i, pIdx->tnum);
      }
      sqlite3VdbeAddOp(v, OP_Close, iCur, 0);
    }
  }

  /*
  ** Return the number of rows that were deleted. If this routine is 
  ** generating code because of a call to sqlite3NestedParse(), do not
  ** invoke the callback function.
  */
  if( db->flags & SQLITE_CountRows && pParse->nested==0 && !pParse->trigStack ){
    sqlite3VdbeAddOp(v, OP_Callback, 1, 0);
    sqlite3VdbeSetNumCols(v, 1);
    sqlite3VdbeSetColName(v, 0, "rows deleted", P3_STATIC);
  }

delete_from_cleanup:
  sqlite3AuthContextPop(&sContext);
  sqlite3SrcListDelete(pTabList);
  sqlite3ExprDelete(pWhere);
  return;
}
Esempio n. 18
0
/*
** This routine is call to handle SQL of the following forms:
**
**    insert into TABLE (IDLIST) values(EXPRLIST)
**    insert into TABLE (IDLIST) select
**
** The IDLIST following the table name is always optional.  If omitted,
** then a list of all columns for the table is substituted.  The IDLIST
** appears in the pColumn parameter.  pColumn is NULL if IDLIST is omitted.
**
** The pList parameter holds EXPRLIST in the first form of the INSERT
** statement above, and pSelect is NULL.  For the second form, pList is
** NULL and pSelect is a pointer to the select statement used to generate
** data for the insert.
**
** The code generated follows one of three templates.  For a simple
** select with data coming from a VALUES clause, the code executes
** once straight down through.  The template looks like this:
**
**         open write cursor to <table> and its indices
**         puts VALUES clause expressions onto the stack
**         write the resulting record into <table>
**         cleanup
**
** If the statement is of the form
**
**   INSERT INTO <table> SELECT ...
**
** And the SELECT clause does not read from <table> at any time, then
** the generated code follows this template:
**
**         goto B
**      A: setup for the SELECT
**         loop over the tables in the SELECT
**           gosub C
**         end loop
**         cleanup after the SELECT
**         goto D
**      B: open write cursor to <table> and its indices
**         goto A
**      C: insert the select result into <table>
**         return
**      D: cleanup
**
** The third template is used if the insert statement takes its
** values from a SELECT but the data is being inserted into a table
** that is also read as part of the SELECT.  In the third form,
** we have to use a intermediate table to store the results of
** the select.  The template is like this:
**
**         goto B
**      A: setup for the SELECT
**         loop over the tables in the SELECT
**           gosub C
**         end loop
**         cleanup after the SELECT
**         goto D
**      C: insert the select result into the intermediate table
**         return
**      B: open a cursor to an intermediate table
**         goto A
**      D: open write cursor to <table> and its indices
**         loop over the intermediate table
**           transfer values form intermediate table into <table>
**         end the loop
**         cleanup
*/
void sqlite3Insert(
  Parse *pParse,        /* Parser context */
  SrcList *pTabList,    /* Name of table into which we are inserting */
  ExprList *pList,      /* List of values to be inserted */
  Select *pSelect,      /* A SELECT statement to use as the data source */
  IdList *pColumn,      /* Column names corresponding to IDLIST. */
  int onError           /* How to handle constraint errors */
){
  Table *pTab;          /* The table to insert into */
  char *zTab;           /* Name of the table into which we are inserting */
  const char *zDb;      /* Name of the database holding this table */
  int i, j, idx;        /* Loop counters */
  Vdbe *v;              /* Generate code into this virtual machine */
  Index *pIdx;          /* For looping over indices of the table */
  int nColumn;          /* Number of columns in the data */
  int base = 0;         /* VDBE Cursor number for pTab */
  int iCont=0,iBreak=0; /* Beginning and end of the loop over srcTab */
  sqlite3 *db;          /* The main database structure */
  int keyColumn = -1;   /* Column that is the INTEGER PRIMARY KEY */
  int endOfLoop;        /* Label for the end of the insertion loop */
  int useTempTable = 0; /* Store SELECT results in intermediate table */
  int srcTab = 0;       /* Data comes from this temporary cursor if >=0 */
  int iSelectLoop = 0;  /* Address of code that implements the SELECT */
  int iCleanup = 0;     /* Address of the cleanup code */
  int iInsertBlock = 0; /* Address of the subroutine used to insert data */
  int iCntMem = 0;      /* Memory cell used for the row counter */
  int newIdx = -1;      /* Cursor for the NEW table */
  Db *pDb;              /* The database containing table being inserted into */
  int counterMem = 0;   /* Memory cell holding AUTOINCREMENT counter */
  int iDb;

#ifndef SQLITE_OMIT_TRIGGER
  int isView;                 /* True if attempting to insert into a view */
  int triggers_exist = 0;     /* True if there are FOR EACH ROW triggers */
#endif

#ifndef SQLITE_OMIT_AUTOINCREMENT
  int counterRowid = 0;  /* Memory cell holding rowid of autoinc counter */
#endif

  if( pParse->nErr || sqlite3MallocFailed() ){
    goto insert_cleanup;
  }
  db = pParse->db;

  /* Locate the table into which we will be inserting new information.
  */
  assert( pTabList->nSrc==1 );
  zTab = pTabList->a[0].zName;
  if( zTab==0 ) goto insert_cleanup;
  pTab = sqlite3SrcListLookup(pParse, pTabList);
  if( pTab==0 ){
    goto insert_cleanup;
  }
  iDb = sqlite3SchemaToIndex(db, pTab->pSchema);
  assert( iDb<db->nDb );
  pDb = &db->aDb[iDb];
  zDb = pDb->zName;
  if( sqlite3AuthCheck(pParse, SQLITE_INSERT, pTab->zName, 0, zDb) ){
    goto insert_cleanup;
  }

  /* Figure out if we have any triggers and if the table being
  ** inserted into is a view
  */
#ifndef SQLITE_OMIT_TRIGGER
  triggers_exist = sqlite3TriggersExist(pParse, pTab, TK_INSERT, 0);
  isView = pTab->pSelect!=0;
#else
# define triggers_exist 0
# define isView 0
#endif
#ifdef SQLITE_OMIT_VIEW
# undef isView
# define isView 0
#endif

  /* Ensure that:
  *  (a) the table is not read-only, 
  *  (b) that if it is a view then ON INSERT triggers exist
  */
  if( sqlite3IsReadOnly(pParse, pTab, triggers_exist) ){
    goto insert_cleanup;
  }
  assert( pTab!=0 );

  /* If pTab is really a view, make sure it has been initialized.
  */
  if( isView && sqlite3ViewGetColumnNames(pParse, pTab) ){
    goto insert_cleanup;
  }

  /* Allocate a VDBE
  */
  v = sqlite3GetVdbe(pParse);
  if( v==0 ) goto insert_cleanup;
  if( pParse->nested==0 ) sqlite3VdbeCountChanges(v);
  sqlite3BeginWriteOperation(pParse, pSelect || triggers_exist, iDb);

  /* if there are row triggers, allocate a temp table for new.* references. */
  if( triggers_exist ){
    newIdx = pParse->nTab++;
  }

#ifndef SQLITE_OMIT_AUTOINCREMENT
  /* If this is an AUTOINCREMENT table, look up the sequence number in the
  ** sqlite_sequence table and store it in memory cell counterMem.  Also
  ** remember the rowid of the sqlite_sequence table entry in memory cell
  ** counterRowid.
  */
  if( pTab->autoInc ){
    int iCur = pParse->nTab;
    int addr = sqlite3VdbeCurrentAddr(v);
    counterRowid = pParse->nMem++;
    counterMem = pParse->nMem++;
    sqlite3OpenTable(pParse, iCur, iDb, pDb->pSchema->pSeqTab, OP_OpenRead);
    sqlite3VdbeAddOp(v, OP_Rewind, iCur, addr+13);
    sqlite3VdbeAddOp(v, OP_Column, iCur, 0);
    sqlite3VdbeOp3(v, OP_String8, 0, 0, pTab->zName, 0);
    sqlite3VdbeAddOp(v, OP_Ne, 0x100, addr+12);
    sqlite3VdbeAddOp(v, OP_Rowid, iCur, 0);
    sqlite3VdbeAddOp(v, OP_MemStore, counterRowid, 1);
    sqlite3VdbeAddOp(v, OP_Column, iCur, 1);
    sqlite3VdbeAddOp(v, OP_MemStore, counterMem, 1);
    sqlite3VdbeAddOp(v, OP_Goto, 0, addr+13);
    sqlite3VdbeAddOp(v, OP_Next, iCur, addr+4);
    sqlite3VdbeAddOp(v, OP_Close, iCur, 0);
  }
#endif /* SQLITE_OMIT_AUTOINCREMENT */

  /* Figure out how many columns of data are supplied.  If the data
  ** is coming from a SELECT statement, then this step also generates
  ** all the code to implement the SELECT statement and invoke a subroutine
  ** to process each row of the result. (Template 2.) If the SELECT
  ** statement uses the the table that is being inserted into, then the
  ** subroutine is also coded here.  That subroutine stores the SELECT
  ** results in a temporary table. (Template 3.)
  */
  if( pSelect ){
    /* Data is coming from a SELECT.  Generate code to implement that SELECT
    */
    int rc, iInitCode;
    iInitCode = sqlite3VdbeAddOp(v, OP_Goto, 0, 0);
    iSelectLoop = sqlite3VdbeCurrentAddr(v);
    iInsertBlock = sqlite3VdbeMakeLabel(v);

    /* Resolve the expressions in the SELECT statement and execute it. */
    rc = sqlite3Select(pParse, pSelect, SRT_Subroutine, iInsertBlock,0,0,0,0);
    if( rc || pParse->nErr || sqlite3MallocFailed() ){
      goto insert_cleanup;
    }

    iCleanup = sqlite3VdbeMakeLabel(v);
    sqlite3VdbeAddOp(v, OP_Goto, 0, iCleanup);
    assert( pSelect->pEList );
    nColumn = pSelect->pEList->nExpr;

    /* Set useTempTable to TRUE if the result of the SELECT statement
    ** should be written into a temporary table.  Set to FALSE if each
    ** row of the SELECT can be written directly into the result table.
    **
    ** A temp table must be used if the table being updated is also one
    ** of the tables being read by the SELECT statement.  Also use a 
    ** temp table in the case of row triggers.
    */
    if( triggers_exist || selectReadsTable(pSelect,pTab->pSchema,pTab->tnum) ){
      useTempTable = 1;
    }

    if( useTempTable ){
      /* Generate the subroutine that SELECT calls to process each row of
      ** the result.  Store the result in a temporary table
      */
      srcTab = pParse->nTab++;
      sqlite3VdbeResolveLabel(v, iInsertBlock);
      sqlite3VdbeAddOp(v, OP_MakeRecord, nColumn, 0);
      sqlite3VdbeAddOp(v, OP_NewRowid, srcTab, 0);
      sqlite3VdbeAddOp(v, OP_Pull, 1, 0);
      sqlite3VdbeAddOp(v, OP_Insert, srcTab, 0);
      sqlite3VdbeAddOp(v, OP_Return, 0, 0);

      /* The following code runs first because the GOTO at the very top
      ** of the program jumps to it.  Create the temporary table, then jump
      ** back up and execute the SELECT code above.
      */
      sqlite3VdbeJumpHere(v, iInitCode);
      sqlite3VdbeAddOp(v, OP_OpenVirtual, srcTab, 0);
      sqlite3VdbeAddOp(v, OP_SetNumColumns, srcTab, nColumn);
      sqlite3VdbeAddOp(v, OP_Goto, 0, iSelectLoop);
      sqlite3VdbeResolveLabel(v, iCleanup);
    }else{
      sqlite3VdbeJumpHere(v, iInitCode);
    }
  }else{
    /* This is the case if the data for the INSERT is coming from a VALUES
    ** clause
    */
    NameContext sNC;
    memset(&sNC, 0, sizeof(sNC));
    sNC.pParse = pParse;
    assert( pList!=0 );
    srcTab = -1;
    useTempTable = 0;
    assert( pList );
    nColumn = pList->nExpr;
    for(i=0; i<nColumn; i++){
      if( sqlite3ExprResolveNames(&sNC, pList->a[i].pExpr) ){
        goto insert_cleanup;
      }
    }
  }

  /* Make sure the number of columns in the source data matches the number
  ** of columns to be inserted into the table.
  */
  if( pColumn==0 && nColumn!=pTab->nCol ){
    sqlite3ErrorMsg(pParse, 
       "table %S has %d columns but %d values were supplied",
       pTabList, 0, pTab->nCol, nColumn);
    goto insert_cleanup;
  }
  if( pColumn!=0 && nColumn!=pColumn->nId ){
    sqlite3ErrorMsg(pParse, "%d values for %d columns", nColumn, pColumn->nId);
    goto insert_cleanup;
  }

  /* If the INSERT statement included an IDLIST term, then make sure
  ** all elements of the IDLIST really are columns of the table and 
  ** remember the column indices.
  **
  ** If the table has an INTEGER PRIMARY KEY column and that column
  ** is named in the IDLIST, then record in the keyColumn variable
  ** the index into IDLIST of the primary key column.  keyColumn is
  ** the index of the primary key as it appears in IDLIST, not as
  ** is appears in the original table.  (The index of the primary
  ** key in the original table is pTab->iPKey.)
  */
  if( pColumn ){
    for(i=0; i<pColumn->nId; i++){
      pColumn->a[i].idx = -1;
    }
    for(i=0; i<pColumn->nId; i++){
      for(j=0; j<pTab->nCol; j++){
        if( sqlite3StrICmp(pColumn->a[i].zName, pTab->aCol[j].zName)==0 ){
          pColumn->a[i].idx = j;
          if( j==pTab->iPKey ){
            keyColumn = i;
          }
          break;
        }
      }
      if( j>=pTab->nCol ){
        if( sqlite3IsRowid(pColumn->a[i].zName) ){
          keyColumn = i;
        }else{
          sqlite3ErrorMsg(pParse, "table %S has no column named %s",
              pTabList, 0, pColumn->a[i].zName);
          pParse->nErr++;
          goto insert_cleanup;
        }
      }
    }
  }

  /* If there is no IDLIST term but the table has an integer primary
  ** key, the set the keyColumn variable to the primary key column index
  ** in the original table definition.
  */
  if( pColumn==0 ){
    keyColumn = pTab->iPKey;
  }

  /* Open the temp table for FOR EACH ROW triggers
  */
  if( triggers_exist ){
    sqlite3VdbeAddOp(v, OP_OpenPseudo, newIdx, 0);
    sqlite3VdbeAddOp(v, OP_SetNumColumns, newIdx, pTab->nCol);
  }
    
  /* Initialize the count of rows to be inserted
  */
  if( db->flags & SQLITE_CountRows ){
    iCntMem = pParse->nMem++;
    sqlite3VdbeAddOp(v, OP_MemInt, 0, iCntMem);
  }

  /* Open tables and indices if there are no row triggers */
  if( !triggers_exist ){
    base = pParse->nTab;
    sqlite3OpenTableAndIndices(pParse, pTab, base, OP_OpenWrite);
  }

  /* If the data source is a temporary table, then we have to create
  ** a loop because there might be multiple rows of data.  If the data
  ** source is a subroutine call from the SELECT statement, then we need
  ** to launch the SELECT statement processing.
  */
  if( useTempTable ){
    iBreak = sqlite3VdbeMakeLabel(v);
    sqlite3VdbeAddOp(v, OP_Rewind, srcTab, iBreak);
    iCont = sqlite3VdbeCurrentAddr(v);
  }else if( pSelect ){
    sqlite3VdbeAddOp(v, OP_Goto, 0, iSelectLoop);
    sqlite3VdbeResolveLabel(v, iInsertBlock);
  }

  /* Run the BEFORE and INSTEAD OF triggers, if there are any
  */
  endOfLoop = sqlite3VdbeMakeLabel(v);
  if( triggers_exist & TRIGGER_BEFORE ){

    /* build the NEW.* reference row.  Note that if there is an INTEGER
    ** PRIMARY KEY into which a NULL is being inserted, that NULL will be
    ** translated into a unique ID for the row.  But on a BEFORE trigger,
    ** we do not know what the unique ID will be (because the insert has
    ** not happened yet) so we substitute a rowid of -1
    */
    if( keyColumn<0 ){
      sqlite3VdbeAddOp(v, OP_Integer, -1, 0);
    }else if( useTempTable ){
      sqlite3VdbeAddOp(v, OP_Column, srcTab, keyColumn);
    }else{
      assert( pSelect==0 );  /* Otherwise useTempTable is true */
      sqlite3ExprCode(pParse, pList->a[keyColumn].pExpr);
      sqlite3VdbeAddOp(v, OP_NotNull, -1, sqlite3VdbeCurrentAddr(v)+3);
      sqlite3VdbeAddOp(v, OP_Pop, 1, 0);
      sqlite3VdbeAddOp(v, OP_Integer, -1, 0);
      sqlite3VdbeAddOp(v, OP_MustBeInt, 0, 0);
    }

    /* Create the new column data
    */
    for(i=0; i<pTab->nCol; i++){
      if( pColumn==0 ){
        j = i;
      }else{
        for(j=0; j<pColumn->nId; j++){
          if( pColumn->a[j].idx==i ) break;
        }
      }
      if( pColumn && j>=pColumn->nId ){
        sqlite3ExprCode(pParse, pTab->aCol[i].pDflt);
      }else if( useTempTable ){
        sqlite3VdbeAddOp(v, OP_Column, srcTab, j); 
      }else{
        assert( pSelect==0 ); /* Otherwise useTempTable is true */
        sqlite3ExprCodeAndCache(pParse, pList->a[j].pExpr);
      }
    }
    sqlite3VdbeAddOp(v, OP_MakeRecord, pTab->nCol, 0);

    /* If this is an INSERT on a view with an INSTEAD OF INSERT trigger,
    ** do not attempt any conversions before assembling the record.
    ** If this is a real table, attempt conversions as required by the
    ** table column affinities.
    */
    if( !isView ){
      sqlite3TableAffinityStr(v, pTab);
    }
    sqlite3VdbeAddOp(v, OP_Insert, newIdx, 0);

    /* Fire BEFORE or INSTEAD OF triggers */
    if( sqlite3CodeRowTrigger(pParse, TK_INSERT, 0, TRIGGER_BEFORE, pTab, 
        newIdx, -1, onError, endOfLoop) ){
      goto insert_cleanup;
    }
  }

  /* If any triggers exists, the opening of tables and indices is deferred
  ** until now.
  */
  if( triggers_exist && !isView ){
    base = pParse->nTab;
    sqlite3OpenTableAndIndices(pParse, pTab, base, OP_OpenWrite);
  }

  /* Push the record number for the new entry onto the stack.  The
  ** record number is a randomly generate integer created by NewRowid
  ** except when the table has an INTEGER PRIMARY KEY column, in which
  ** case the record number is the same as that column. 
  */
  if( !isView ){
    if( keyColumn>=0 ){
      if( useTempTable ){
        sqlite3VdbeAddOp(v, OP_Column, srcTab, keyColumn);
      }else if( pSelect ){
        sqlite3VdbeAddOp(v, OP_Dup, nColumn - keyColumn - 1, 1);
      }else{
        sqlite3ExprCode(pParse, pList->a[keyColumn].pExpr);
      }
      /* If the PRIMARY KEY expression is NULL, then use OP_NewRowid
      ** to generate a unique primary key value.
      */
      sqlite3VdbeAddOp(v, OP_NotNull, -1, sqlite3VdbeCurrentAddr(v)+3);
      sqlite3VdbeAddOp(v, OP_Pop, 1, 0);
      sqlite3VdbeAddOp(v, OP_NewRowid, base, counterMem);
      sqlite3VdbeAddOp(v, OP_MustBeInt, 0, 0);
    }else{
      sqlite3VdbeAddOp(v, OP_NewRowid, base, counterMem);
    }
#ifndef SQLITE_OMIT_AUTOINCREMENT
    if( pTab->autoInc ){
      sqlite3VdbeAddOp(v, OP_MemMax, counterMem, 0);
    }
#endif /* SQLITE_OMIT_AUTOINCREMENT */

    /* Push onto the stack, data for all columns of the new entry, beginning
    ** with the first column.
    */
    for(i=0; i<pTab->nCol; i++){
      if( i==pTab->iPKey ){
        /* The value of the INTEGER PRIMARY KEY column is always a NULL.
        ** Whenever this column is read, the record number will be substituted
        ** in its place.  So will fill this column with a NULL to avoid
        ** taking up data space with information that will never be used. */
        sqlite3VdbeAddOp(v, OP_Null, 0, 0);
        continue;
      }
      if( pColumn==0 ){
        j = i;
      }else{
        for(j=0; j<pColumn->nId; j++){
          if( pColumn->a[j].idx==i ) break;
        }
      }
      if( pColumn && j>=pColumn->nId ){
        sqlite3ExprCode(pParse, pTab->aCol[i].pDflt);
      }else if( useTempTable ){
        sqlite3VdbeAddOp(v, OP_Column, srcTab, j); 
      }else if( pSelect ){
        sqlite3VdbeAddOp(v, OP_Dup, i+nColumn-j, 1);
      }else{
        sqlite3ExprCode(pParse, pList->a[j].pExpr);
      }
    }

    /* Generate code to check constraints and generate index keys and
    ** do the insertion.
    */
    sqlite3GenerateConstraintChecks(pParse, pTab, base, 0, keyColumn>=0,
                                   0, onError, endOfLoop);
    sqlite3CompleteInsertion(pParse, pTab, base, 0,0,0,
                            (triggers_exist & TRIGGER_AFTER)!=0 ? newIdx : -1);
  }

  /* Update the count of rows that are inserted
  */
  if( (db->flags & SQLITE_CountRows)!=0 ){
    sqlite3VdbeAddOp(v, OP_MemIncr, 1, iCntMem);
  }

  if( triggers_exist ){
    /* Close all tables opened */
    if( !isView ){
      sqlite3VdbeAddOp(v, OP_Close, base, 0);
      for(idx=1, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, idx++){
        sqlite3VdbeAddOp(v, OP_Close, idx+base, 0);
      }
    }

    /* Code AFTER triggers */
    if( sqlite3CodeRowTrigger(pParse, TK_INSERT, 0, TRIGGER_AFTER, pTab,
          newIdx, -1, onError, endOfLoop) ){
      goto insert_cleanup;
    }
  }

  /* The bottom of the loop, if the data source is a SELECT statement
  */
  sqlite3VdbeResolveLabel(v, endOfLoop);
  if( useTempTable ){
    sqlite3VdbeAddOp(v, OP_Next, srcTab, iCont);
    sqlite3VdbeResolveLabel(v, iBreak);
    sqlite3VdbeAddOp(v, OP_Close, srcTab, 0);
  }else if( pSelect ){
    sqlite3VdbeAddOp(v, OP_Pop, nColumn, 0);
    sqlite3VdbeAddOp(v, OP_Return, 0, 0);
    sqlite3VdbeResolveLabel(v, iCleanup);
  }

  if( !triggers_exist ){
    /* Close all tables opened */
    sqlite3VdbeAddOp(v, OP_Close, base, 0);
    for(idx=1, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, idx++){
      sqlite3VdbeAddOp(v, OP_Close, idx+base, 0);
    }
  }

#ifndef SQLITE_OMIT_AUTOINCREMENT
  /* Update the sqlite_sequence table by storing the content of the
  ** counter value in memory counterMem back into the sqlite_sequence
  ** table.
  */
  if( pTab->autoInc ){
    int iCur = pParse->nTab;
    int addr = sqlite3VdbeCurrentAddr(v);
    sqlite3OpenTable(pParse, iCur, iDb, pDb->pSchema->pSeqTab, OP_OpenWrite);
    sqlite3VdbeAddOp(v, OP_MemLoad, counterRowid, 0);
    sqlite3VdbeAddOp(v, OP_NotNull, -1, addr+7);
    sqlite3VdbeAddOp(v, OP_Pop, 1, 0);
    sqlite3VdbeAddOp(v, OP_NewRowid, iCur, 0);
    sqlite3VdbeOp3(v, OP_String8, 0, 0, pTab->zName, 0);
    sqlite3VdbeAddOp(v, OP_MemLoad, counterMem, 0);
    sqlite3VdbeAddOp(v, OP_MakeRecord, 2, 0);
    sqlite3VdbeAddOp(v, OP_Insert, iCur, 0);
    sqlite3VdbeAddOp(v, OP_Close, iCur, 0);
  }
#endif

  /*
  ** Return the number of rows inserted. If this routine is 
  ** generating code because of a call to sqlite3NestedParse(), do not
  ** invoke the callback function.
  */
  if( db->flags & SQLITE_CountRows && pParse->nested==0 && !pParse->trigStack ){
    sqlite3VdbeAddOp(v, OP_MemLoad, iCntMem, 0);
    sqlite3VdbeAddOp(v, OP_Callback, 1, 0);
    sqlite3VdbeSetNumCols(v, 1);
    sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "rows inserted", P3_STATIC);
  }

insert_cleanup:
  sqlite3SrcListDelete(pTabList);
  sqlite3ExprListDelete(pList);
  sqlite3SelectDelete(pSelect);
  sqlite3IdListDelete(pColumn);
}
Esempio n. 19
0
/*
** Process an UPDATE statement.
**
**   UPDATE OR IGNORE table_wxyz SET a=b, c=d WHERE e<5 AND f NOT NULL;
**          \_______/ \________/     \______/       \________________/
*            onError   pTabList      pChanges             pWhere
*/
void sqlite3Update(
  Parse *pParse,         /* The parser context */
  SrcList *pTabList,     /* The table in which we should change things */
  ExprList *pChanges,    /* Things to be changed */
  Expr *pWhere,          /* The WHERE clause.  May be null */
  int onError            /* How to handle constraint errors */
){
  int i, j;              /* Loop counters */
  Table *pTab;           /* The table to be updated */
  int addr = 0;          /* VDBE instruction address of the start of the loop */
  WhereInfo *pWInfo;     /* Information about the WHERE clause */
  Vdbe *v;               /* The virtual database engine */
  Index *pIdx;           /* For looping over indices */
  int nIdx;              /* Number of indices that need updating */
  int nIdxTotal;         /* Total number of indices */
  int iCur;              /* VDBE Cursor number of pTab */
  sqlite3 *db;           /* The database structure */
  Index **apIdx = 0;     /* An array of indices that need updating too */
  char *aIdxUsed = 0;    /* aIdxUsed[i]==1 if the i-th index is used */
  int *aXRef = 0;        /* aXRef[i] is the index in pChanges->a[] of the
                         ** an expression for the i-th column of the table.
                         ** aXRef[i]==-1 if the i-th column is not changed. */
  int chngRecno;         /* True if the record number is being changed */
  Expr *pRecnoExpr = 0;  /* Expression defining the new record number */
  int openAll = 0;       /* True if all indices need to be opened */
  AuthContext sContext;  /* The authorization context */
  NameContext sNC;       /* The name-context to resolve expressions in */

#ifndef SQLITE_OMIT_TRIGGER
  int isView;                  /* Trying to update a view */
  int triggers_exist = 0;      /* True if any row triggers exist */
#endif

  int newIdx      = -1;  /* index of trigger "new" temp table       */
  int oldIdx      = -1;  /* index of trigger "old" temp table       */

  sContext.pParse = 0;
  if( pParse->nErr || sqlite3_malloc_failed ) goto update_cleanup;
  db = pParse->db;
  assert( pTabList->nSrc==1 );

  /* Locate the table which we want to update. 
  */
  pTab = sqlite3SrcListLookup(pParse, pTabList);
  if( pTab==0 ) goto update_cleanup;

  /* Figure out if we have any triggers and if the table being
  ** updated is a view
  */
#ifndef SQLITE_OMIT_TRIGGER
  triggers_exist = sqlite3TriggersExist(pParse, pTab, TK_UPDATE, pChanges);
  isView = pTab->pSelect!=0;
#else
# define triggers_exist 0
# define isView 0
#endif
#ifdef SQLITE_OMIT_VIEW
# undef isView
# define isView 0
#endif

  if( sqlite3IsReadOnly(pParse, pTab, triggers_exist) ){
    goto update_cleanup;
  }
  if( isView ){
    if( sqlite3ViewGetColumnNames(pParse, pTab) ){
      goto update_cleanup;
    }
  }
  aXRef = sqliteMallocRaw( sizeof(int) * pTab->nCol );
  if( aXRef==0 ) goto update_cleanup;
  for(i=0; i<pTab->nCol; i++) aXRef[i] = -1;

  /* If there are FOR EACH ROW triggers, allocate cursors for the
  ** special OLD and NEW tables
  */
  if( triggers_exist ){
    newIdx = pParse->nTab++;
    oldIdx = pParse->nTab++;
  }

  /* Allocate a cursors for the main database table and for all indices.
  ** The index cursors might not be used, but if they are used they
  ** need to occur right after the database cursor.  So go ahead and
  ** allocate enough space, just in case.
  */
  pTabList->a[0].iCursor = iCur = pParse->nTab++;
  for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
    pParse->nTab++;
  }

  /* Initialize the name-context */
  memset(&sNC, 0, sizeof(sNC));
  sNC.pParse = pParse;
  sNC.pSrcList = pTabList;

  /* Resolve the column names in all the expressions of the
  ** of the UPDATE statement.  Also find the column index
  ** for each column to be updated in the pChanges array.  For each
  ** column to be updated, make sure we have authorization to change
  ** that column.
  */
  chngRecno = 0;
  for(i=0; i<pChanges->nExpr; i++){
    if( sqlite3ExprResolveNames(&sNC, pChanges->a[i].pExpr) ){
      goto update_cleanup;
    }
    for(j=0; j<pTab->nCol; j++){
      if( sqlite3StrICmp(pTab->aCol[j].zName, pChanges->a[i].zName)==0 ){
        if( j==pTab->iPKey ){
          chngRecno = 1;
          pRecnoExpr = pChanges->a[i].pExpr;
        }
        aXRef[j] = i;
        break;
      }
    }
    if( j>=pTab->nCol ){
      if( sqlite3IsRowid(pChanges->a[i].zName) ){
        chngRecno = 1;
        pRecnoExpr = pChanges->a[i].pExpr;
      }else{
        sqlite3ErrorMsg(pParse, "no such column: %s", pChanges->a[i].zName);
        goto update_cleanup;
      }
    }
#ifndef SQLITE_OMIT_AUTHORIZATION
    {
      int rc;
      rc = sqlite3AuthCheck(pParse, SQLITE_UPDATE, pTab->zName,
                           pTab->aCol[j].zName, db->aDb[pTab->iDb].zName);
      if( rc==SQLITE_DENY ){
        goto update_cleanup;
      }else if( rc==SQLITE_IGNORE ){
        aXRef[j] = -1;
      }
    }
#endif
  }

  /* Allocate memory for the array apIdx[] and fill it with pointers to every
  ** index that needs to be updated.  Indices only need updating if their
  ** key includes one of the columns named in pChanges or if the record
  ** number of the original table entry is changing.
  */
  for(nIdx=nIdxTotal=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, nIdxTotal++){
    if( chngRecno ){
      i = 0;
    }else {
      for(i=0; i<pIdx->nColumn; i++){
        if( aXRef[pIdx->aiColumn[i]]>=0 ) break;
      }
    }
    if( i<pIdx->nColumn ) nIdx++;
  }
  if( nIdxTotal>0 ){
    apIdx = sqliteMallocRaw( sizeof(Index*) * nIdx + nIdxTotal );
    if( apIdx==0 ) goto update_cleanup;
    aIdxUsed = (char*)&apIdx[nIdx];
  }
  for(nIdx=j=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, j++){
    if( chngRecno ){
      i = 0;
    }else{
      for(i=0; i<pIdx->nColumn; i++){
        if( aXRef[pIdx->aiColumn[i]]>=0 ) break;
      }
    }
    if( i<pIdx->nColumn ){
      if( sqlite3CheckIndexCollSeq(pParse, pIdx) ) goto update_cleanup;
      apIdx[nIdx++] = pIdx;
      aIdxUsed[j] = 1;
    }else{
      aIdxUsed[j] = 0;
    }
  }

  /* Resolve the column names in all the expressions in the
  ** WHERE clause.
  */
  if( sqlite3ExprResolveNames(&sNC, pWhere) ){
    goto update_cleanup;
  }

  /* Start the view context
  */
  if( isView ){
    sqlite3AuthContextPush(pParse, &sContext, pTab->zName);
  }

  /* Begin generating code.
  */
  v = sqlite3GetVdbe(pParse);
  if( v==0 ) goto update_cleanup;
  if( pParse->nested==0 ) sqlite3VdbeCountChanges(v);
  sqlite3BeginWriteOperation(pParse, 1, pTab->iDb);

  /* If we are trying to update a view, construct that view into
  ** a temporary table.
  */
  if( isView ){
    Select *pView;
    pView = sqlite3SelectDup(pTab->pSelect);
    sqlite3Select(pParse, pView, SRT_TempTable, iCur, 0, 0, 0, 0);
    sqlite3SelectDelete(pView);
  }

  /* Begin the database scan
  */
  pWInfo = sqlite3WhereBegin(pParse, pTabList, pWhere, 0, 0);
  if( pWInfo==0 ) goto update_cleanup;

  /* Remember the index of every item to be updated.
  */
  sqlite3VdbeAddOp(v, OP_Recno, iCur, 0);
  sqlite3VdbeAddOp(v, OP_ListWrite, 0, 0);

  /* End the database scan loop.
  */
  sqlite3WhereEnd(pWInfo);

  /* Initialize the count of updated rows
  */
  if( db->flags & SQLITE_CountRows && !pParse->trigStack ){
    sqlite3VdbeAddOp(v, OP_Integer, 0, 0);
  }

  if( triggers_exist ){
    /* Create pseudo-tables for NEW and OLD
    */
    sqlite3VdbeAddOp(v, OP_OpenPseudo, oldIdx, 0);
    sqlite3VdbeAddOp(v, OP_SetNumColumns, oldIdx, pTab->nCol);
    sqlite3VdbeAddOp(v, OP_OpenPseudo, newIdx, 0);
    sqlite3VdbeAddOp(v, OP_SetNumColumns, newIdx, pTab->nCol);

    /* The top of the update loop for when there are triggers.
    */
    sqlite3VdbeAddOp(v, OP_ListRewind, 0, 0);
    addr = sqlite3VdbeAddOp(v, OP_ListRead, 0, 0);
    sqlite3VdbeAddOp(v, OP_Dup, 0, 0);

    /* Open a cursor and make it point to the record that is
    ** being updated.
    */
    sqlite3VdbeAddOp(v, OP_Dup, 0, 0);
    if( !isView ){
      sqlite3OpenTableForReading(v, iCur, pTab);
    }
    sqlite3VdbeAddOp(v, OP_MoveGe, iCur, 0);

    /* Generate the OLD table
    */
    sqlite3VdbeAddOp(v, OP_Recno, iCur, 0);
    sqlite3VdbeAddOp(v, OP_RowData, iCur, 0);
    sqlite3VdbeAddOp(v, OP_PutIntKey, oldIdx, 0);

    /* Generate the NEW table
    */
    if( chngRecno ){
      sqlite3ExprCodeAndCache(pParse, pRecnoExpr);
    }else{
      sqlite3VdbeAddOp(v, OP_Recno, iCur, 0);
    }
    for(i=0; i<pTab->nCol; i++){
      if( i==pTab->iPKey ){
        sqlite3VdbeAddOp(v, OP_String8, 0, 0);
        continue;
      }
      j = aXRef[i];
      if( j<0 ){
        sqlite3VdbeAddOp(v, OP_Column, iCur, i);
        sqlite3ColumnDefault(v, pTab, i);
      }else{
        sqlite3ExprCodeAndCache(pParse, pChanges->a[j].pExpr);
      }
    }
    sqlite3VdbeAddOp(v, OP_MakeRecord, pTab->nCol, 0);
    if( !isView ){
      sqlite3TableAffinityStr(v, pTab);
    }
    if( pParse->nErr ) goto update_cleanup;
    sqlite3VdbeAddOp(v, OP_PutIntKey, newIdx, 0);
    if( !isView ){
      sqlite3VdbeAddOp(v, OP_Close, iCur, 0);
    }

    /* Fire the BEFORE and INSTEAD OF triggers
    */
    if( sqlite3CodeRowTrigger(pParse, TK_UPDATE, pChanges, TRIGGER_BEFORE, pTab,
          newIdx, oldIdx, onError, addr) ){
      goto update_cleanup;
    }
  }

  if( !isView ){
    /* 
    ** Open every index that needs updating.  Note that if any
    ** index could potentially invoke a REPLACE conflict resolution 
    ** action, then we need to open all indices because we might need
    ** to be deleting some records.
    */
    sqlite3VdbeAddOp(v, OP_Integer, pTab->iDb, 0);
    sqlite3VdbeAddOp(v, OP_OpenWrite, iCur, pTab->tnum);
    sqlite3VdbeAddOp(v, OP_SetNumColumns, iCur, pTab->nCol);
    if( onError==OE_Replace ){
      openAll = 1;
    }else{
      openAll = 0;
      for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
        if( pIdx->onError==OE_Replace ){
          openAll = 1;
          break;
        }
      }
    }
    for(i=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, i++){
      if( openAll || aIdxUsed[i] ){
        sqlite3VdbeAddOp(v, OP_Integer, pIdx->iDb, 0);
        sqlite3VdbeOp3(v, OP_OpenWrite, iCur+i+1, pIdx->tnum,
                       (char*)&pIdx->keyInfo, P3_KEYINFO);
        assert( pParse->nTab>iCur+i+1 );
      }
    }

    /* Loop over every record that needs updating.  We have to load
    ** the old data for each record to be updated because some columns
    ** might not change and we will need to copy the old value.
    ** Also, the old data is needed to delete the old index entires.
    ** So make the cursor point at the old record.
    */
    if( !triggers_exist ){
      sqlite3VdbeAddOp(v, OP_ListRewind, 0, 0);
      addr = sqlite3VdbeAddOp(v, OP_ListRead, 0, 0);
      sqlite3VdbeAddOp(v, OP_Dup, 0, 0);
    }
    sqlite3VdbeAddOp(v, OP_NotExists, iCur, addr);

    /* If the record number will change, push the record number as it
    ** will be after the update. (The old record number is currently
    ** on top of the stack.)
    */
    if( chngRecno ){
      sqlite3ExprCode(pParse, pRecnoExpr);
      sqlite3VdbeAddOp(v, OP_MustBeInt, 0, 0);
    }

    /* Compute new data for this record.  
    */
    for(i=0; i<pTab->nCol; i++){
      if( i==pTab->iPKey ){
        sqlite3VdbeAddOp(v, OP_String8, 0, 0);
        continue;
      }
      j = aXRef[i];
      if( j<0 ){
        sqlite3VdbeAddOp(v, OP_Column, iCur, i);
        sqlite3ColumnDefault(v, pTab, i);
      }else{
        sqlite3ExprCode(pParse, pChanges->a[j].pExpr);
      }
    }

    /* Do constraint checks
    */
    sqlite3GenerateConstraintChecks(pParse, pTab, iCur, aIdxUsed, chngRecno, 1,
                                   onError, addr);

    /* Delete the old indices for the current record.
    */
    sqlite3GenerateRowIndexDelete(db, v, pTab, iCur, aIdxUsed);

    /* If changing the record number, delete the old record.
    */
    if( chngRecno ){
      sqlite3VdbeAddOp(v, OP_Delete, iCur, 0);
    }

    /* Create the new index entries and the new record.
    */
    sqlite3CompleteInsertion(pParse, pTab, iCur, aIdxUsed, chngRecno, 1, -1);
  }

  /* Increment the row counter 
  */
  if( db->flags & SQLITE_CountRows && !pParse->trigStack){
    sqlite3VdbeAddOp(v, OP_AddImm, 1, 0);
  }

  /* If there are triggers, close all the cursors after each iteration
  ** through the loop.  The fire the after triggers.
  */
  if( triggers_exist ){
    if( !isView ){
      for(i=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, i++){
        if( openAll || aIdxUsed[i] )
          sqlite3VdbeAddOp(v, OP_Close, iCur+i+1, 0);
      }
      sqlite3VdbeAddOp(v, OP_Close, iCur, 0);
    }
    if( sqlite3CodeRowTrigger(pParse, TK_UPDATE, pChanges, TRIGGER_AFTER, pTab, 
          newIdx, oldIdx, onError, addr) ){
      goto update_cleanup;
    }
  }

  /* Repeat the above with the next record to be updated, until
  ** all record selected by the WHERE clause have been updated.
  */
  sqlite3VdbeAddOp(v, OP_Goto, 0, addr);
  sqlite3VdbeChangeP2(v, addr, sqlite3VdbeCurrentAddr(v));
  sqlite3VdbeAddOp(v, OP_ListReset, 0, 0);

  /* Close all tables if there were no FOR EACH ROW triggers */
  if( !triggers_exist ){
    for(i=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, i++){
      if( openAll || aIdxUsed[i] ){
        sqlite3VdbeAddOp(v, OP_Close, iCur+i+1, 0);
      }
    }
    sqlite3VdbeAddOp(v, OP_Close, iCur, 0);
  }else{
    sqlite3VdbeAddOp(v, OP_Close, newIdx, 0);
    sqlite3VdbeAddOp(v, OP_Close, oldIdx, 0);
  }

  /*
  ** Return the number of rows that were changed. If this routine is 
  ** generating code because of a call to sqlite3NestedParse(), do not
  ** invoke the callback function.
  */
  if( db->flags & SQLITE_CountRows && !pParse->trigStack && pParse->nested==0 ){
    sqlite3VdbeAddOp(v, OP_Callback, 1, 0);
    sqlite3VdbeSetNumCols(v, 1);
    sqlite3VdbeSetColName(v, 0, "rows updated", P3_STATIC);
  }

update_cleanup:
  sqlite3AuthContextPop(&sContext);
  sqliteFree(apIdx);
  sqliteFree(aXRef);
  sqlite3SrcListDelete(pTabList);
  sqlite3ExprListDelete(pChanges);
  sqlite3ExprDelete(pWhere);
  return;
}
Esempio n. 20
0
/*
** Generate an expression tree to implement the WHERE, ORDER BY,
** and LIMIT/OFFSET portion of DELETE and UPDATE statements.
**
**     DELETE FROM table_wxyz WHERE a<5 ORDER BY a LIMIT 1;
**                            \__________________________/
**                               pLimitWhere (pInClause)
*/
Expr *sqlite3LimitWhere(
  Parse *pParse,               /* The parser context */
  SrcList *pSrc,               /* the FROM clause -- which tables to scan */
  Expr *pWhere,                /* The WHERE clause.  May be null */
  ExprList *pOrderBy,          /* The ORDER BY clause.  May be null */
  Expr *pLimit,                /* The LIMIT clause.  May be null */
  Expr *pOffset,               /* The OFFSET clause.  May be null */
  char *zStmtType              /* Either DELETE or UPDATE.  For error messages. */
){
  Expr *pWhereRowid = NULL;    /* WHERE rowid .. */
  Expr *pInClause = NULL;      /* WHERE rowid IN ( select ) */
  Expr *pSelectRowid = NULL;   /* SELECT rowid ... */
  ExprList *pEList = NULL;     /* Expression list contaning only pSelectRowid */
  SrcList *pSelectSrc = NULL;  /* SELECT rowid FROM x ... (dup of pSrc) */
  Select *pSelect = NULL;      /* Complete SELECT tree */

  /* Check that there isn't an ORDER BY without a LIMIT clause.
  */
  if( pOrderBy && (pLimit == 0) ) {
    sqlite3ErrorMsg(pParse, "ORDER BY without LIMIT on %s", zStmtType);
    goto limit_where_cleanup_2;
  }

  /* We only need to generate a select expression if there
  ** is a limit/offset term to enforce.
  */
  if( pLimit == 0 ) {
    /* if pLimit is null, pOffset will always be null as well. */
    assert( pOffset == 0 );
    return pWhere;
  }

  /* Generate a select expression tree to enforce the limit/offset 
  ** term for the DELETE or UPDATE statement.  For example:
  **   DELETE FROM table_a WHERE col1=1 ORDER BY col2 LIMIT 1 OFFSET 1
  ** becomes:
  **   DELETE FROM table_a WHERE rowid IN ( 
  **     SELECT rowid FROM table_a WHERE col1=1 ORDER BY col2 LIMIT 1 OFFSET 1
  **   );
  */

  pSelectRowid = sqlite3PExpr(pParse, TK_ROW, 0, 0, 0);
  if( pSelectRowid == 0 ) goto limit_where_cleanup_2;
  pEList = sqlite3ExprListAppend(pParse, 0, pSelectRowid);
  if( pEList == 0 ) goto limit_where_cleanup_2;

  /* duplicate the FROM clause as it is needed by both the DELETE/UPDATE tree
  ** and the SELECT subtree. */
  pSelectSrc = sqlite3SrcListDup(pParse->db, pSrc, 0);
  if( pSelectSrc == 0 ) {
    sqlite3ExprListDelete(pParse->db, pEList);
    goto limit_where_cleanup_2;
  }

  /* generate the SELECT expression tree. */
  pSelect = sqlite3SelectNew(pParse,pEList,pSelectSrc,pWhere,0,0,
                             pOrderBy,0,pLimit,pOffset);
  if( pSelect == 0 ) return 0;

  /* now generate the new WHERE rowid IN clause for the DELETE/UDPATE */
  pWhereRowid = sqlite3PExpr(pParse, TK_ROW, 0, 0, 0);
  if( pWhereRowid == 0 ) goto limit_where_cleanup_1;
  pInClause = sqlite3PExpr(pParse, TK_IN, pWhereRowid, 0, 0);
  if( pInClause == 0 ) goto limit_where_cleanup_1;

  pInClause->x.pSelect = pSelect;
  pInClause->flags |= EP_xIsSelect;
  sqlite3ExprSetHeight(pParse, pInClause);
  return pInClause;

  /* something went wrong. clean up anything allocated. */
limit_where_cleanup_1:
  sqlite3SelectDelete(pParse->db, pSelect);
  return 0;

limit_where_cleanup_2:
  sqlite3ExprDelete(pParse->db, pWhere);
  sqlite3ExprListDelete(pParse->db, pOrderBy);
  sqlite3ExprDelete(pParse->db, pLimit);
  sqlite3ExprDelete(pParse->db, pOffset);
  return 0;
}
/*
 ** Generate VDBE code for the statements inside the body of a single
 ** trigger.
 */
static int codeTriggerProgram(
                              Parse *pParse,            /* The parser context */
                              TriggerStep *pStepList,   /* List of statements inside the trigger body */
                              int orconf                /* Conflict algorithm. (OE_Abort, etc) */
){
    TriggerStep *pStep;
    Vdbe *v = pParse->pVdbe;
    sqlite3 *db = pParse->db;
    
    assert( pParse->pTriggerTab && pParse->pToplevel );
    assert( pStepList );
    assert( v!=0 );
    for(pStep=pStepList; pStep; pStep=pStep->pNext){
        /* Figure out the ON CONFLICT policy that will be used for this step
         ** of the trigger program. If the statement that caused this trigger
         ** to fire had an explicit ON CONFLICT, then use it. Otherwise, use
         ** the ON CONFLICT policy that was specified as part of the trigger
         ** step statement. Example:
         **
         **   CREATE TRIGGER AFTER INSERT ON t1 BEGIN;
         **     INSERT OR REPLACE INTO t2 VALUES(new.a, new.b);
         **   END;
         **
         **   INSERT INTO t1 ... ;            -- insert into t2 uses REPLACE policy
         **   INSERT OR IGNORE INTO t1 ... ;  -- insert into t2 uses IGNORE policy
         */
        pParse->eOrconf = (orconf==OE_Default)?pStep->orconf:(u8)orconf;
        
        /* Clear the cookieGoto flag. When coding triggers, the cookieGoto
         ** variable is used as a flag to indicate to sqlite3ExprCodeConstants()
         ** that it is not safe to refactor constants (this happens after the
         ** start of the first loop in the SQL statement is coded - at that
         ** point code may be conditionally executed, so it is no longer safe to
         ** initialize constant register values).  */
        assert( pParse->cookieGoto==0 || pParse->cookieGoto==-1 );
        pParse->cookieGoto = 0;
        
        switch( pStep->op ){
            case TK_UPDATE: {
                sqlite3Update(pParse,
                              targetSrcList(pParse, pStep),
                              sqlite3ExprListDup(db, pStep->pExprList, 0),
                              sqlite3ExprDup(db, pStep->pWhere, 0),
                              pParse->eOrconf
                              );
                break;
            }
            case TK_INSERT: {
                sqlite3Insert(pParse,
                              targetSrcList(pParse, pStep),
                              sqlite3ExprListDup(db, pStep->pExprList, 0),
                              sqlite3SelectDup(db, pStep->pSelect, 0),
                              sqlite3IdListDup(db, pStep->pIdList),
                              pParse->eOrconf
                              );
                break;
            }
            case TK_DELETE: {
                sqlite3DeleteFrom(pParse,
                                  targetSrcList(pParse, pStep),
                                  sqlite3ExprDup(db, pStep->pWhere, 0)
                                  );
                break;
            }
            default: assert( pStep->op==TK_SELECT ); {
                SelectDest sDest;
                Select *pSelect = sqlite3SelectDup(db, pStep->pSelect, 0);
                sqlite3SelectDestInit(&sDest, SRT_Discard, 0);
                sqlite3Select(pParse, pSelect, &sDest);
                sqlite3SelectDelete(db, pSelect);
                break;
            }
        }
        if( pStep->op!=TK_SELECT ){
            sqlite3VdbeAddOp0(v, OP_ResetCount);
        }
    }
    
    return 0;
}
Esempio n. 22
0
/*
** This function is called when an UPDATE or DELETE operation is being 
** compiled on table pTab, which is the parent table of foreign-key pFKey.
** If the current operation is an UPDATE, then the pChanges parameter is
** passed a pointer to the list of columns being modified. If it is a
** DELETE, pChanges is passed a NULL pointer.
**
** It returns a pointer to a Trigger structure containing a trigger
** equivalent to the ON UPDATE or ON DELETE action specified by pFKey.
** If the action is "NO ACTION" or "RESTRICT", then a NULL pointer is
** returned (these actions require no special handling by the triggers
** sub-system, code for them is created by fkScanChildren()).
**
** For example, if pFKey is the foreign key and pTab is table "p" in 
** the following schema:
**
**   CREATE TABLE p(pk PRIMARY KEY);
**   CREATE TABLE c(ck REFERENCES p ON DELETE CASCADE);
**
** then the returned trigger structure is equivalent to:
**
**   CREATE TRIGGER ... DELETE ON p BEGIN
**     DELETE FROM c WHERE ck = old.pk;
**   END;
**
** The returned pointer is cached as part of the foreign key object. It
** is eventually freed along with the rest of the foreign key object by 
** sqlite3FkDelete().
*/
static Trigger *fkActionTrigger(
  Parse *pParse,                  /* Parse context */
  Table *pTab,                    /* Table being updated or deleted from */
  FKey *pFKey,                    /* Foreign key to get action for */
  ExprList *pChanges              /* Change-list for UPDATE, NULL for DELETE */
){
  sqlite3 *db = pParse->db;       /* Database handle */
  int action;                     /* One of OE_None, OE_Cascade etc. */
  Trigger *pTrigger;              /* Trigger definition to return */
  int iAction = (pChanges!=0);    /* 1 for UPDATE, 0 for DELETE */

  action = pFKey->aAction[iAction];
  pTrigger = pFKey->apTrigger[iAction];

  if( action!=OE_None && !pTrigger ){
    u8 enableLookaside;           /* Copy of db->lookaside.bEnabled */
    char const *zFrom;            /* Name of child table */
    int nFrom;                    /* Length in bytes of zFrom */
    Index *pIdx = 0;              /* Parent key index for this FK */
    int *aiCol = 0;               /* child table cols -> parent key cols */
    TriggerStep *pStep = 0;        /* First (only) step of trigger program */
    Expr *pWhere = 0;             /* WHERE clause of trigger step */
    ExprList *pList = 0;          /* Changes list if ON UPDATE CASCADE */
    Select *pSelect = 0;          /* If RESTRICT, "SELECT RAISE(...)" */
    int i;                        /* Iterator variable */
    Expr *pWhen = 0;              /* WHEN clause for the trigger */

    if( locateFkeyIndex(pParse, pTab, pFKey, &pIdx, &aiCol) ) return 0;
    assert( aiCol || pFKey->nCol==1 );

    for(i=0; i<pFKey->nCol; i++){
      Token tOld = { "old", 3 };  /* Literal "old" token */
      Token tNew = { "new", 3 };  /* Literal "new" token */
      Token tFromCol;             /* Name of column in child table */
      Token tToCol;               /* Name of column in parent table */
      int iFromCol;               /* Idx of column in child table */
      Expr *pEq;                  /* tFromCol = OLD.tToCol */

      iFromCol = aiCol ? aiCol[i] : pFKey->aCol[0].iFrom;
      assert( iFromCol>=0 );
      tToCol.z = pIdx ? pTab->aCol[pIdx->aiColumn[i]].zName : "oid";
      tFromCol.z = pFKey->pFrom->aCol[iFromCol].zName;

      tToCol.n = sqlite3Strlen30(tToCol.z);
      tFromCol.n = sqlite3Strlen30(tFromCol.z);

      /* Create the expression "OLD.zToCol = zFromCol". It is important
      ** that the "OLD.zToCol" term is on the LHS of the = operator, so
      ** that the affinity and collation sequence associated with the
      ** parent table are used for the comparison. */
      pEq = sqlite3PExpr(pParse, TK_EQ,
          sqlite3PExpr(pParse, TK_DOT, 
            sqlite3PExpr(pParse, TK_ID, 0, 0, &tOld),
            sqlite3PExpr(pParse, TK_ID, 0, 0, &tToCol)
          , 0),
          sqlite3PExpr(pParse, TK_ID, 0, 0, &tFromCol)
      , 0);
      pWhere = sqlite3ExprAnd(db, pWhere, pEq);

      /* For ON UPDATE, construct the next term of the WHEN clause.
      ** The final WHEN clause will be like this:
      **
      **    WHEN NOT(old.col1 IS new.col1 AND ... AND old.colN IS new.colN)
      */
      if( pChanges ){
        pEq = sqlite3PExpr(pParse, TK_IS,
            sqlite3PExpr(pParse, TK_DOT, 
              sqlite3PExpr(pParse, TK_ID, 0, 0, &tOld),
              sqlite3PExpr(pParse, TK_ID, 0, 0, &tToCol),
              0),
            sqlite3PExpr(pParse, TK_DOT, 
              sqlite3PExpr(pParse, TK_ID, 0, 0, &tNew),
              sqlite3PExpr(pParse, TK_ID, 0, 0, &tToCol),
              0),
            0);
        pWhen = sqlite3ExprAnd(db, pWhen, pEq);
      }
  
      if( action!=OE_Restrict && (action!=OE_Cascade || pChanges) ){
        Expr *pNew;
        if( action==OE_Cascade ){
          pNew = sqlite3PExpr(pParse, TK_DOT, 
            sqlite3PExpr(pParse, TK_ID, 0, 0, &tNew),
            sqlite3PExpr(pParse, TK_ID, 0, 0, &tToCol)
          , 0);
        }else if( action==OE_SetDflt ){
          Expr *pDflt = pFKey->pFrom->aCol[iFromCol].pDflt;
          if( pDflt ){
            pNew = sqlite3ExprDup(db, pDflt, 0);
          }else{
            pNew = sqlite3PExpr(pParse, TK_NULL, 0, 0, 0);
          }
        }else{
          pNew = sqlite3PExpr(pParse, TK_NULL, 0, 0, 0);
        }
        pList = sqlite3ExprListAppend(pParse, pList, pNew);
        sqlite3ExprListSetName(pParse, pList, &tFromCol, 0);
      }
    }
    sqlite3DbFree(db, aiCol);

    zFrom = pFKey->pFrom->zName;
    nFrom = sqlite3Strlen30(zFrom);

    if( action==OE_Restrict ){
      Token tFrom;
      Expr *pRaise; 

      tFrom.z = zFrom;
      tFrom.n = nFrom;
      pRaise = sqlite3Expr(db, TK_RAISE, "foreign key constraint failed");
      if( pRaise ){
        pRaise->affinity = OE_Abort;
      }
      pSelect = sqlite3SelectNew(pParse, 
          sqlite3ExprListAppend(pParse, 0, pRaise),
          sqlite3SrcListAppend(db, 0, &tFrom, 0),
          pWhere,
          0, 0, 0, 0, 0, 0
      );
      pWhere = 0;
    }

    /* Disable lookaside memory allocation */
    enableLookaside = db->lookaside.bEnabled;
    db->lookaside.bEnabled = 0;

    pTrigger = (Trigger *)sqlite3DbMallocZero(db, 
        sizeof(Trigger) +         /* struct Trigger */
        sizeof(TriggerStep) +     /* Single step in trigger program */
        nFrom + 1                 /* Space for pStep->target.z */
    );
    if( pTrigger ){
      pStep = pTrigger->step_list = (TriggerStep *)&pTrigger[1];
      pStep->target.z = (char *)&pStep[1];
      pStep->target.n = nFrom;
      memcpy((char *)pStep->target.z, zFrom, nFrom);
  
      pStep->pWhere = sqlite3ExprDup(db, pWhere, EXPRDUP_REDUCE);
      pStep->pExprList = sqlite3ExprListDup(db, pList, EXPRDUP_REDUCE);
      pStep->pSelect = sqlite3SelectDup(db, pSelect, EXPRDUP_REDUCE);
      if( pWhen ){
        pWhen = sqlite3PExpr(pParse, TK_NOT, pWhen, 0, 0);
        pTrigger->pWhen = sqlite3ExprDup(db, pWhen, EXPRDUP_REDUCE);
      }
    }

    /* Re-enable the lookaside buffer, if it was disabled earlier. */
    db->lookaside.bEnabled = enableLookaside;

    sqlite3ExprDelete(db, pWhere);
    sqlite3ExprDelete(db, pWhen);
    sqlite3ExprListDelete(db, pList);
    sqlite3SelectDelete(db, pSelect);
    if( db->mallocFailed==1 ){
      fkTriggerDelete(db, pTrigger);
      return 0;
    }
    assert( pStep!=0 );

    switch( action ){
      case OE_Restrict:
        pStep->op = TK_SELECT; 
        break;
      case OE_Cascade: 
        if( !pChanges ){ 
          pStep->op = TK_DELETE; 
          break; 
        }
      default:
        pStep->op = TK_UPDATE;
    }
    pStep->pTrig = pTrigger;
    pTrigger->pSchema = pTab->pSchema;
    pTrigger->pTabSchema = pTab->pSchema;
    pFKey->apTrigger[iAction] = pTrigger;
    pTrigger->op = (pChanges ? TK_UPDATE : TK_DELETE);
  }

  return pTrigger;
}
Esempio n. 23
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/*
** Generate VDBE code for the statements inside the body of a single 
** trigger.
*/
static int codeTriggerProgram(
  Parse *pParse,            /* The parser context */
  TriggerStep *pStepList,   /* List of statements inside the trigger body */
  int orconf                /* Conflict algorithm. (OE_Abort, etc) */  
){
  TriggerStep *pStep;
  Vdbe *v = pParse->pVdbe;
  sqlite3 *db = pParse->db;

  assert( pParse->pTriggerTab && pParse->pToplevel );
  assert( pStepList );
  assert( v!=0 );
  for(pStep=pStepList; pStep; pStep=pStep->pNext){
    /* Figure out the ON CONFLICT policy that will be used for this step
    ** of the trigger program. If the statement that caused this trigger
    ** to fire had an explicit ON CONFLICT, then use it. Otherwise, use
    ** the ON CONFLICT policy that was specified as part of the trigger
    ** step statement. Example:
    **
    **   CREATE TRIGGER AFTER INSERT ON t1 BEGIN;
    **     INSERT OR REPLACE INTO t2 VALUES(new.a, new.b);
    **   END;
    **
    **   INSERT INTO t1 ... ;            -- insert into t2 uses REPLACE policy
    **   INSERT OR IGNORE INTO t1 ... ;  -- insert into t2 uses IGNORE policy
    */
    pParse->eOrconf = (orconf==OE_Default)?pStep->orconf:(u8)orconf;
    assert( pParse->okConstFactor==0 );

    switch( pStep->op ){
      case TK_UPDATE: {
        sqlite3Update(pParse, 
          targetSrcList(pParse, pStep),
          sqlite3ExprListDup(db, pStep->pExprList, 0), 
          sqlite3ExprDup(db, pStep->pWhere, 0), 
          pParse->eOrconf
        );
        break;
      }
      case TK_INSERT: {
        sqlite3Insert(pParse, 
          targetSrcList(pParse, pStep),
          sqlite3SelectDup(db, pStep->pSelect, 0), 
          sqlite3IdListDup(db, pStep->pIdList), 
          pParse->eOrconf
        );
        break;
      }
      case TK_DELETE: {
        sqlite3DeleteFrom(pParse, 
          targetSrcList(pParse, pStep),
          sqlite3ExprDup(db, pStep->pWhere, 0)
        );
        break;
      }
      default: assert( pStep->op==TK_SELECT ); {
        SelectDest sDest;
        Select *pSelect = sqlite3SelectDup(db, pStep->pSelect, 0);
        sqlite3SelectDestInit(&sDest, SRT_Discard, 0);
        sqlite3Select(pParse, pSelect, &sDest);
        sqlite3SelectDelete(db, pSelect);
        break;
      }
    } 
    if( pStep->op!=TK_SELECT ){
      sqlite3VdbeAddOp0(v, OP_ResetCount);
    }
  }

  return 0;
}
Esempio n. 24
0
/*
** Generate VDBE code for zero or more statements inside the body of a
** trigger.  
*/
static int codeTriggerProgram(
  Parse *pParse,            /* The parser context */
  TriggerStep *pStepList,   /* List of statements inside the trigger body */
  int orconfin              /* Conflict algorithm. (OE_Abort, etc) */  
){
  TriggerStep * pTriggerStep = pStepList;
  int orconf;
  Vdbe *v = pParse->pVdbe;
  sqlite3 *db = pParse->db;

  assert( pTriggerStep!=0 );
  assert( v!=0 );
  sqlite3VdbeAddOp(v, OP_ContextPush, 0, 0);
  VdbeComment((v, "# begin trigger %s", pStepList->pTrig->name));
  while( pTriggerStep ){
    orconf = (orconfin == OE_Default)?pTriggerStep->orconf:orconfin;
    pParse->trigStack->orconf = orconf;
    switch( pTriggerStep->op ){
      case TK_SELECT: {
        Select *ss = sqlite3SelectDup(db, pTriggerStep->pSelect);
        if( ss ){
          sqlite3SelectResolve(pParse, ss, 0);
          sqlite3Select(pParse, ss, SRT_Discard, 0, 0, 0, 0, 0);
          sqlite3SelectDelete(ss);
        }
        break;
      }
      case TK_UPDATE: {
        SrcList *pSrc;
        pSrc = targetSrcList(pParse, pTriggerStep);
        sqlite3VdbeAddOp(v, OP_ResetCount, 0, 0);
        sqlite3Update(pParse, pSrc,
                sqlite3ExprListDup(db, pTriggerStep->pExprList), 
                sqlite3ExprDup(db, pTriggerStep->pWhere), orconf);
        sqlite3VdbeAddOp(v, OP_ResetCount, 1, 0);
        break;
      }
      case TK_INSERT: {
        SrcList *pSrc;
        pSrc = targetSrcList(pParse, pTriggerStep);
        sqlite3VdbeAddOp(v, OP_ResetCount, 0, 0);
        sqlite3Insert(pParse, pSrc,
          sqlite3ExprListDup(db, pTriggerStep->pExprList), 
          sqlite3SelectDup(db, pTriggerStep->pSelect), 
          sqlite3IdListDup(db, pTriggerStep->pIdList), orconf);
        sqlite3VdbeAddOp(v, OP_ResetCount, 1, 0);
        break;
      }
      case TK_DELETE: {
        SrcList *pSrc;
        sqlite3VdbeAddOp(v, OP_ResetCount, 0, 0);
        pSrc = targetSrcList(pParse, pTriggerStep);
        sqlite3DeleteFrom(pParse, pSrc, 
                          sqlite3ExprDup(db, pTriggerStep->pWhere));
        sqlite3VdbeAddOp(v, OP_ResetCount, 1, 0);
        break;
      }
      default:
        assert(0);
    } 
    pTriggerStep = pTriggerStep->pNext;
  }
  sqlite3VdbeAddOp(v, OP_ContextPop, 0, 0);
  VdbeComment((v, "# end trigger %s", pStepList->pTrig->name));

  return 0;
}
Esempio n. 25
0
/*
** Generate code for an UPDATE of a virtual table.
**
** The strategy is that we create an ephemerial table that contains
** for each row to be changed:
**
**   (A)  The original rowid of that row.
**   (B)  The revised rowid for the row. (note1)
**   (C)  The content of every column in the row.
**
** Then we loop over this ephemeral table and for each row in
** the ephermeral table call VUpdate.
**
** When finished, drop the ephemeral table.
**
** (note1) Actually, if we know in advance that (A) is always the same
** as (B) we only store (A), then duplicate (A) when pulling
** it out of the ephemeral table before calling VUpdate.
*/
static void updateVirtualTable(
  Parse *pParse,       /* The parsing context */
  SrcList *pSrc,       /* The virtual table to be modified */
  Table *pTab,         /* The virtual table */
  ExprList *pChanges,  /* The columns to change in the UPDATE statement */
  Expr *pRowid,        /* Expression used to recompute the rowid */
  int *aXRef,          /* Mapping from columns of pTab to entries in pChanges */
  Expr *pWhere         /* WHERE clause of the UPDATE statement */
){
  Vdbe *v = pParse->pVdbe;  /* Virtual machine under construction */
  ExprList *pEList = 0;     /* The result set of the SELECT statement */
  Select *pSelect = 0;      /* The SELECT statement */
  Expr *pExpr;              /* Temporary expression */
  int ephemTab;             /* Table holding the result of the SELECT */
  int i;                    /* Loop counter */
  int addr;                 /* Address of top of loop */
  int iReg;                 /* First register in set passed to OP_VUpdate */
  sqlite3 *db = pParse->db; /* Database connection */
  const char *pVTab = (const char*)sqlite3GetVTable(db, pTab);
  SelectDest dest;

  /* Construct the SELECT statement that will find the new values for
  ** all updated rows. 
  */
  pEList = sqlite3ExprListAppend(pParse, 0, sqlite3Expr(db, TK_ID, "_rowid_"));
  if( pRowid ){
    pEList = sqlite3ExprListAppend(pParse, pEList,
                                   sqlite3ExprDup(db, pRowid, 0));
  }
  assert( pTab->iPKey<0 );
  for(i=0; i<pTab->nCol; i++){
    if( aXRef[i]>=0 ){
      pExpr = sqlite3ExprDup(db, pChanges->a[aXRef[i]].pExpr, 0);
    }else{
      pExpr = sqlite3Expr(db, TK_ID, pTab->aCol[i].zName);
    }
    pEList = sqlite3ExprListAppend(pParse, pEList, pExpr);
  }
  pSelect = sqlite3SelectNew(pParse, pEList, pSrc, pWhere, 0, 0, 0, 0, 0, 0);
  
  /* Create the ephemeral table into which the update results will
  ** be stored.
  */
  assert( v );
  ephemTab = pParse->nTab++;
  sqlite3VdbeAddOp2(v, OP_OpenEphemeral, ephemTab, pTab->nCol+1+(pRowid!=0));
  sqlite3VdbeChangeP5(v, BTREE_UNORDERED);

  /* fill the ephemeral table 
  */
  sqlite3SelectDestInit(&dest, SRT_Table, ephemTab);
  sqlite3Select(pParse, pSelect, &dest);

  /* Generate code to scan the ephemeral table and call VUpdate. */
  iReg = ++pParse->nMem;
  pParse->nMem += pTab->nCol+1;
  addr = sqlite3VdbeAddOp2(v, OP_Rewind, ephemTab, 0);
  sqlite3VdbeAddOp3(v, OP_Column,  ephemTab, 0, iReg);
  sqlite3VdbeAddOp3(v, OP_Column, ephemTab, (pRowid?1:0), iReg+1);
  for(i=0; i<pTab->nCol; i++){
    sqlite3VdbeAddOp3(v, OP_Column, ephemTab, i+1+(pRowid!=0), iReg+2+i);
  }
  sqlite3VtabMakeWritable(pParse, pTab);
  sqlite3VdbeAddOp4(v, OP_VUpdate, 0, pTab->nCol+2, iReg, pVTab, P4_VTAB);
  sqlite3MayAbort(pParse);
  sqlite3VdbeAddOp2(v, OP_Next, ephemTab, addr+1);
  sqlite3VdbeJumpHere(v, addr);
  sqlite3VdbeAddOp2(v, OP_Close, ephemTab, 0);

  /* Cleanup */
  sqlite3SelectDelete(db, pSelect);  
}
Esempio n. 26
0
/*
** Generate VDBE code for zero or more statements inside the body of a
** trigger.  
*/
static int codeTriggerProgram(
  Parse *pParse,            /* The parser context */
  TriggerStep *pStepList,   /* List of statements inside the trigger body */
  int orconfin              /* Conflict algorithm. (OE_Abort, etc) */  
){
  TriggerStep * pTriggerStep = pStepList;
  int orconf;

  while( pTriggerStep ){
    int saveNTab = pParse->nTab;
 
    orconf = (orconfin == OE_Default)?pTriggerStep->orconf:orconfin;
    pParse->trigStack->orconf = orconf;
    switch( pTriggerStep->op ){
      case TK_SELECT: {
	Select * ss = sqlite3SelectDup(pTriggerStep->pSelect);		  
	assert(ss);
	assert(ss->pSrc);
	sqlite3Select(pParse, ss, SRT_Discard, 0, 0, 0, 0, 0);
	sqlite3SelectDelete(ss);
	break;
      }
      case TK_UPDATE: {
        SrcList *pSrc;
        pSrc = targetSrcList(pParse, pTriggerStep);
        sqlite3VdbeAddOp(pParse->pVdbe, OP_ResetCount, 0, 0);
        sqlite3VdbeAddOp(pParse->pVdbe, OP_ListPush, 0, 0);
        sqlite3Update(pParse, pSrc,
		sqlite3ExprListDup(pTriggerStep->pExprList), 
		sqlite3ExprDup(pTriggerStep->pWhere), orconf);
        sqlite3VdbeAddOp(pParse->pVdbe, OP_ListPop, 0, 0);
        sqlite3VdbeAddOp(pParse->pVdbe, OP_ResetCount, 1, 0);
        break;
      }
      case TK_INSERT: {
        SrcList *pSrc;
        pSrc = targetSrcList(pParse, pTriggerStep);
        sqlite3VdbeAddOp(pParse->pVdbe, OP_ResetCount, 0, 0);
        sqlite3Insert(pParse, pSrc,
          sqlite3ExprListDup(pTriggerStep->pExprList), 
          sqlite3SelectDup(pTriggerStep->pSelect), 
          sqlite3IdListDup(pTriggerStep->pIdList), orconf);
        sqlite3VdbeAddOp(pParse->pVdbe, OP_ResetCount, 1, 0);
        break;
      }
      case TK_DELETE: {
        SrcList *pSrc;
        sqlite3VdbeAddOp(pParse->pVdbe, OP_ResetCount, 0, 0);
        sqlite3VdbeAddOp(pParse->pVdbe, OP_ListPush, 0, 0);
        pSrc = targetSrcList(pParse, pTriggerStep);
        sqlite3DeleteFrom(pParse, pSrc, sqlite3ExprDup(pTriggerStep->pWhere));
        sqlite3VdbeAddOp(pParse->pVdbe, OP_ListPop, 0, 0);
        sqlite3VdbeAddOp(pParse->pVdbe, OP_ResetCount, 1, 0);
        break;
      }
      default:
        assert(0);
    } 
    pParse->nTab = saveNTab;
    pTriggerStep = pTriggerStep->pNext;
  }

  return 0;
}
Esempio n. 27
0
/*
** Generate code for an UPDATE of a virtual table.
**
** The strategy is that we create an ephemerial table that contains
** for each row to be changed:
**
**   (A)  The original rowid of that row.
**   (B)  The revised rowid for the row. (note1)
**   (C)  The content of every column in the row.
**
** Then we loop over this ephemeral table and for each row in
** the ephermeral table call VUpdate.
**
** When finished, drop the ephemeral table.
**
** (note1) Actually, if we know in advance that (A) is always the same
** as (B) we only store (A), then duplicate (A) when pulling
** it out of the ephemeral table before calling VUpdate.
*/
static void updateVirtualTable(
  Parse *pParse,       /* The parsing context */
  SrcList *pSrc,       /* The virtual table to be modified */
  Table *pTab,         /* The virtual table */
  ExprList *pChanges,  /* The columns to change in the UPDATE statement */
  Expr *pRowid,        /* Expression used to recompute the rowid */
  int *aXRef,          /* Mapping from columns of pTab to entries in pChanges */
  Expr *pWhere         /* WHERE clause of the UPDATE statement */
){
  Vdbe *v = pParse->pVdbe;  /* Virtual machine under construction */
  ExprList *pEList = 0;     /* The result set of the SELECT statement */
  Select *pSelect = 0;      /* The SELECT statement */
  Expr *pExpr;              /* Temporary expression */
  int ephemTab;             /* Table holding the result of the SELECT */
  int i;                    /* Loop counter */
  int addr;                 /* Address of top of loop */

  /* Construct the SELECT statement that will find the new values for
  ** all updated rows. 
  */
  pEList = sqlite3ExprListAppend(0, sqlite3CreateIdExpr("_rowid_"), 0);
  if( pRowid ){
    pEList = sqlite3ExprListAppend(pEList, sqlite3ExprDup(pRowid), 0);
  }
  assert( pTab->iPKey<0 );
  for(i=0; i<pTab->nCol; i++){
    if( aXRef[i]>=0 ){
      pExpr = sqlite3ExprDup(pChanges->a[aXRef[i]].pExpr);
    }else{
      pExpr = sqlite3CreateIdExpr(pTab->aCol[i].zName);
    }
    pEList = sqlite3ExprListAppend(pEList, pExpr, 0);
  }
  pSelect = sqlite3SelectNew(pEList, pSrc, pWhere, 0, 0, 0, 0, 0, 0);
  
  /* Create the ephemeral table into which the update results will
  ** be stored.
  */
  assert( v );
  ephemTab = pParse->nTab++;
  sqlite3VdbeAddOp(v, OP_OpenEphemeral, ephemTab, pTab->nCol+1+(pRowid!=0));

  /* fill the ephemeral table 
  */
  sqlite3Select(pParse, pSelect, SRT_Table, ephemTab, 0, 0, 0, 0);

  /*
  ** Generate code to scan the ephemeral table and call VDelete and
  ** VInsert
  */
  sqlite3VdbeAddOp(v, OP_Rewind, ephemTab, 0);
  addr = sqlite3VdbeCurrentAddr(v);
  sqlite3VdbeAddOp(v, OP_Column,  ephemTab, 0);
  if( pRowid ){
    sqlite3VdbeAddOp(v, OP_Column, ephemTab, 1);
  }else{
    sqlite3VdbeAddOp(v, OP_Dup, 0, 0);
  }
  for(i=0; i<pTab->nCol; i++){
    sqlite3VdbeAddOp(v, OP_Column, ephemTab, i+1+(pRowid!=0));
  }
  pParse->pVirtualLock = pTab;
  sqlite3VdbeOp3(v, OP_VUpdate, 0, pTab->nCol+2, 
                     (const char*)pTab->pVtab, P3_VTAB);
  sqlite3VdbeAddOp(v, OP_Next, ephemTab, addr);
  sqlite3VdbeAddOp(v, OP_Close, ephemTab, 0);

  /* Cleanup */
  sqlite3SelectDelete(pSelect);  
}
Esempio n. 28
0
static void updateVirtualTable(
  Parse *pParse,       
  SrcList *pSrc,       
  Table *pTab,         
  ExprList *pChanges,  
  Expr *pRowid,        
  int *aXRef,          
  Expr *pWhere         
){
  Vdbe *v = pParse->pVdbe;  
  ExprList *pEList = 0;     
  Select *pSelect = 0;      
  Expr *pExpr;              
  int ephemTab;             
  int i;                    
  int addr;                 
  int iReg;                 
  sqlite3 *db = pParse->db; 
  const char *pVTab = (const char*)sqlite3GetVTable(db, pTab);
  SelectDest dest;

  pEList = sqlite3ExprListAppend(pParse, 0, sqlite3Expr(db, TK_ID, "_rowid_"));
  if( pRowid ){
    pEList = sqlite3ExprListAppend(pParse, pEList,
                                   sqlite3ExprDup(db, pRowid, 0));
  }
  assert( pTab->iPKey<0 );
  for(i=0; i<pTab->nCol; i++){
    if( aXRef[i]>=0 ){
      pExpr = sqlite3ExprDup(db, pChanges->a[aXRef[i]].pExpr, 0);
    }else{
      pExpr = sqlite3Expr(db, TK_ID, pTab->aCol[i].zName);
    }
    pEList = sqlite3ExprListAppend(pParse, pEList, pExpr);
  }
  pSelect = sqlite3SelectNew(pParse, pEList, pSrc, pWhere, 0, 0, 0, 0, 0, 0);
  
  assert( v );
  ephemTab = pParse->nTab++;
  sqlite3VdbeAddOp2(v, OP_OpenEphemeral, ephemTab, pTab->nCol+1+(pRowid!=0));
  sqlite3VdbeChangeP5(v, BTREE_UNORDERED);

  sqlite3SelectDestInit(&dest, SRT_Table, ephemTab);
  sqlite3Select(pParse, pSelect, &dest);

  
  iReg = ++pParse->nMem;
  pParse->nMem += pTab->nCol+1;
  addr = sqlite3VdbeAddOp2(v, OP_Rewind, ephemTab, 0);
  sqlite3VdbeAddOp3(v, OP_Column,  ephemTab, 0, iReg);
  sqlite3VdbeAddOp3(v, OP_Column, ephemTab, (pRowid?1:0), iReg+1);
  for(i=0; i<pTab->nCol; i++){
    sqlite3VdbeAddOp3(v, OP_Column, ephemTab, i+1+(pRowid!=0), iReg+2+i);
  }
  sqlite3VtabMakeWritable(pParse, pTab);
  sqlite3VdbeAddOp4(v, OP_VUpdate, 0, pTab->nCol+2, iReg, pVTab, P4_VTAB);
  sqlite3MayAbort(pParse);
  sqlite3VdbeAddOp2(v, OP_Next, ephemTab, addr+1);
  sqlite3VdbeJumpHere(v, addr);
  sqlite3VdbeAddOp2(v, OP_Close, ephemTab, 0);

  
  sqlite3SelectDelete(db, pSelect);  
}