Ejemplo n.º 1
0
int sqliteCompileSQLStmt(Parse *pParse, Block *b, SQLStmt* pSql){
  Vdbe *v = sqliteGetVdbe(pParse);
  int i,j;

  switch( pSql->op ){
  case TK_SELECT: {
	assert(pSql->pSelect);
	assert(pSql->pSelect->pSrc);
	sqliteSelect(pParse, pSql->pSelect, SRT_Stack, 0, 0, 0, 0);
	if( pSql->pExprList->nExpr!=pSql->pSelect->pEList->nExpr ) {
      sqliteErrorMsg(pParse, "INTO list does not match column list", 0);
	  return 1;
	}
	for(i=0; i<pSql->pExprList->nExpr; i++) {
	  Expr *e = pSql->pExprList->a[i].pExpr;
	  if( e->op!=TK_ID ) {
      sqliteErrorMsg(pParse, "Bad lvalue in INTO list", 0);
  		return 1;
	  }
      if( sqliteExprProcResolve(pParse, b, e) ){
        return 1;
	  }
 	  assert( e->op==TK_VAR );
	  if( e->flags==EP_NotNull ){
      j = sqliteVdbeMakeLabel(v);
      sqliteVdbeAddOp(v, OP_NotNull, -1, i);
	    sqliteVdbeOp3(v, OP_Halt, SQLITE_CONSTRAINT, OE_Abort,
                         "attempt to store null in non-null var", P3_STATIC);
      sqliteVdbeResolveLabel(v, j);
	  }
      sqliteVdbeAddOp(v, OP_MemStore, e->iColumn, 1);
	}
	break;
  }
  case TK_UPDATE: {
    SrcList *pSrc;
    pSrc = sqliteSrcListAppend(0, &pSql->target, 0);
    sqliteUpdate(pParse, pSrc, pSql->pExprList, pSql->pWhere, pSql->orconf);
    break;
  }
  case TK_INSERT: {
    SrcList *pSrc;
    pSrc = sqliteSrcListAppend(0, &pSql->target, 0);
    sqliteInsert(pParse, pSrc, pSql->pExprList, pSql->pSelect, pSql->pIdList, pSql->orconf);
    break;
  }
  case TK_DELETE: {
    SrcList *pSrc;
    pSrc = sqliteSrcListAppend(0, &pSql->target, 0);
    sqliteDeleteFrom(pParse, pSrc, pSql->pWhere);
    break;
  }
  default:
    assert(0);
  } 

  return 0;
}
Ejemplo n.º 2
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 = sqliteSelectDup(pTriggerStep->pSelect);		  
	assert(ss);
	assert(ss->pSrc);
	sqliteSelect(pParse, ss, SRT_Discard, 0, 0, 0, 0);
	sqliteSelectDelete(ss);
	break;
      }
      case TK_UPDATE: {
        SrcList *pSrc;
        pSrc = targetSrcList(pParse, pTriggerStep);
        sqliteVdbeAddOp(pParse->pVdbe, OP_ListPush, 0, 0);
        sqliteUpdate(pParse, pSrc,
		sqliteExprListDup(pTriggerStep->pExprList), 
		sqliteExprDup(pTriggerStep->pWhere), orconf);
        sqliteVdbeAddOp(pParse->pVdbe, OP_ListPop, 0, 0);
        break;
      }
      case TK_INSERT: {
        SrcList *pSrc;
        pSrc = targetSrcList(pParse, pTriggerStep);
        sqliteInsert(pParse, pSrc,
          sqliteExprListDup(pTriggerStep->pExprList), 
          sqliteSelectDup(pTriggerStep->pSelect), 
          sqliteIdListDup(pTriggerStep->pIdList), orconf);
        break;
      }
      case TK_DELETE: {
        SrcList *pSrc;
        sqliteVdbeAddOp(pParse->pVdbe, OP_ListPush, 0, 0);
        pSrc = targetSrcList(pParse, pTriggerStep);
        sqliteDeleteFrom(pParse, pSrc, sqliteExprDup(pTriggerStep->pWhere));
        sqliteVdbeAddOp(pParse->pVdbe, OP_ListPop, 0, 0);
        break;
      }
      default:
        assert(0);
    } 
    pParse->nTab = saveNTab;
    pTriggerStep = pTriggerStep->pNext;
  }

  return 0;
}
Ejemplo n.º 3
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 sqliteUpdate(
  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;              /* 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 */
  sqlite *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;      /* Expression defining the new record number */
  int openAll;           /* True if all indices need to be opened */
  int isView;            /* Trying to update a view */
  AuthContext sContext;  /* The authorization context */

  int before_triggers;         /* True if there are any BEFORE triggers */
  int after_triggers;          /* True if there are any AFTER triggers */
  int row_triggers_exist = 0;  /* True if any row triggers exist */

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

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

  /* Locate the table which we want to update. 
  */
  pTab = sqliteSrcListLookup(pParse, pTabList);
  if( pTab==0 ) goto update_cleanup;
  before_triggers = sqliteTriggersExist(pParse, pTab->pTrigger, 
            TK_UPDATE, TK_BEFORE, TK_ROW, pChanges);
  after_triggers = sqliteTriggersExist(pParse, pTab->pTrigger, 
            TK_UPDATE, TK_AFTER, TK_ROW, pChanges);
  row_triggers_exist = before_triggers || after_triggers;
  isView = pTab->pSelect!=0;
  if( sqliteIsReadOnly(pParse, pTab, before_triggers) ){
    goto update_cleanup;
  }
  if( isView ){
    if( sqliteViewGetColumnNames(pParse, pTab) ){
      goto update_cleanup;
    }
  }
  aXRef = sqliteMalloc( 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( row_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++;
  }

  /* 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( sqliteExprResolveIds(pParse, pTabList, 0, pChanges->a[i].pExpr) ){
      goto update_cleanup;
    }
    if( sqliteExprCheck(pParse, pChanges->a[i].pExpr, 0, 0) ){
      goto update_cleanup;
    }
    for(j=0; j<pTab->nCol; j++){
      if( sqliteStrICmp(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( sqliteIsRowid(pChanges->a[i].zName) ){
        chngRecno = 1;
        pRecnoExpr = pChanges->a[i].pExpr;
      }else{
        sqliteErrorMsg(pParse, "no such column: %s", pChanges->a[i].zName);
        goto update_cleanup;
      }
    }
#ifndef SQLITE_OMIT_AUTHORIZATION
    {
      int rc;
      rc = sqliteAuthCheck(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 = sqliteMalloc( 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 ){
      apIdx[nIdx++] = pIdx;
      aIdxUsed[j] = 1;
    }else{
      aIdxUsed[j] = 0;
    }
  }

  /* Resolve the column names in all the expressions in the
  ** WHERE clause.
  */
  if( pWhere ){
    if( sqliteExprResolveIds(pParse, pTabList, 0, pWhere) ){
      goto update_cleanup;
    }
    if( sqliteExprCheck(pParse, pWhere, 0, 0) ){
      goto update_cleanup;
    }
  }

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

  /* Begin generating code.
  */
  v = sqliteGetVdbe(pParse);
  if( v==0 ) goto update_cleanup;
  sqliteBeginWriteOperation(pParse, 1, pTab->iDb);

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

  /* Begin the database scan
  */
  pWInfo = sqliteWhereBegin(pParse, pTabList, pWhere, 1, 0);
  if( pWInfo==0 ) goto update_cleanup;

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

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

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

  if( row_triggers_exist ){
    /* Create pseudo-tables for NEW and OLD
    */
    sqliteVdbeAddOp(v, OP_OpenPseudo, oldIdx, 0);
    sqliteVdbeAddOp(v, OP_OpenPseudo, newIdx, 0);

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

    /* Open a cursor and make it point to the record that is
    ** being updated.
    */
    sqliteVdbeAddOp(v, OP_Dup, 0, 0);
    if( !isView ){
      sqliteVdbeAddOp(v, OP_Integer, pTab->iDb, 0);
      sqliteVdbeAddOp(v, OP_OpenRead, iCur, pTab->tnum);
    }
    sqliteVdbeAddOp(v, OP_MoveTo, iCur, 0);

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

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

    /* Fire the BEFORE and INSTEAD OF triggers
    */
    if( sqliteCodeRowTrigger(pParse, TK_UPDATE, pChanges, TK_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.
    */
    sqliteVdbeAddOp(v, OP_Integer, pTab->iDb, 0);
    sqliteVdbeAddOp(v, OP_OpenWrite, iCur, pTab->tnum);
    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] ){
        sqliteVdbeAddOp(v, OP_Integer, pIdx->iDb, 0);
        sqliteVdbeAddOp(v, OP_OpenWrite, iCur+i+1, pIdx->tnum);
        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( !row_triggers_exist ){
      sqliteVdbeAddOp(v, OP_ListRewind, 0, 0);
      addr = sqliteVdbeAddOp(v, OP_ListRead, 0, 0);
      sqliteVdbeAddOp(v, OP_Dup, 0, 0);
    }
    sqliteVdbeAddOp(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 ){
      sqliteExprCode(pParse, pRecnoExpr);
      sqliteVdbeAddOp(v, OP_MustBeInt, 0, 0);
    }

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

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

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

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

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

  /* Increment the row counter 
  */
  if( db->flags & SQLITE_CountRows && !pParse->trigStack){
    sqliteVdbeAddOp(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( row_triggers_exist ){
    if( !isView ){
      for(i=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, i++){
        if( openAll || aIdxUsed[i] )
          sqliteVdbeAddOp(v, OP_Close, iCur+i+1, 0);
      }
      sqliteVdbeAddOp(v, OP_Close, iCur, 0);
      pParse->nTab = iCur;
    }
    if( sqliteCodeRowTrigger(pParse, TK_UPDATE, pChanges, TK_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.
  */
  sqliteVdbeAddOp(v, OP_Goto, 0, addr);
  sqliteVdbeChangeP2(v, addr, sqliteVdbeCurrentAddr(v));
  sqliteVdbeAddOp(v, OP_ListReset, 0, 0);

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

  sqliteVdbeAddOp(v, OP_SetCounts, 0, 0);
  sqliteEndWriteOperation(pParse);

  /*
  ** Return the number of rows that were changed.
  */
  if( db->flags & SQLITE_CountRows && !pParse->trigStack ){
    sqliteVdbeOp3(v, OP_ColumnName, 0, 1, "rows updated", P3_STATIC);
    sqliteVdbeAddOp(v, OP_Callback, 1, 0);
  }

update_cleanup:
  sqliteAuthContextPop(&sContext);
  sqliteFree(apIdx);
  sqliteFree(aXRef);
  sqliteSrcListDelete(pTabList);
  sqliteExprListDelete(pChanges);
  sqliteExprDelete(pWhere);
  return;
}
Ejemplo n.º 4
0
/*
** Process a DELETE FROM statement.
*/
void sqliteDeleteFrom(
  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;         /* 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 */
  sqlite *db;            /* Main database structure */
  int isView;            /* True if attempting to delete from a view */
  AuthContext sContext;  /* Authorization context */

  int row_triggers_exist = 0;  /* True if any triggers exist */
  int before_triggers;         /* True if there are BEFORE triggers */
  int after_triggers;          /* True if there are AFTER triggers */
  int oldIdx = -1;             /* Cursor for the OLD table of AFTER triggers */

  sContext.pParse = 0;
  if( pParse->nErr || sqlite_malloc_failed ){
    pTabList = 0;
    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 = sqliteSrcListLookup(pParse, pTabList);
  if( pTab==0 )  goto delete_from_cleanup;
  before_triggers = sqliteTriggersExist(pParse, pTab->pTrigger, 
                         TK_DELETE, TK_BEFORE, TK_ROW, 0);
  after_triggers = sqliteTriggersExist(pParse, pTab->pTrigger, 
                         TK_DELETE, TK_AFTER, TK_ROW, 0);
  row_triggers_exist = before_triggers || after_triggers;
  isView = pTab->pSelect!=0;
  if( sqliteIsReadOnly(pParse, pTab, before_triggers) ){
    goto delete_from_cleanup;
  }
  assert( pTab->iDb<db->nDb );
  zDb = db->aDb[pTab->iDb].zName;
  if( sqliteAuthCheck(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 && sqliteViewGetColumnNames(pParse, pTab) ){
    goto delete_from_cleanup;
  }

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

  /* Resolve the column names in all the expressions.
  */
  assert( pTabList->nSrc==1 );
  iCur = pTabList->a[0].iCursor = pParse->nTab++;
  if( pWhere ){
    if( sqliteExprResolveIds(pParse, pTabList, 0, pWhere) ){
      goto delete_from_cleanup;
    }
    if( sqliteExprCheck(pParse, pWhere, 0, 0) ){
      goto delete_from_cleanup;
    }
  }

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

  /* Begin generating code.
  */
  v = sqliteGetVdbe(pParse);
  if( v==0 ){
    goto delete_from_cleanup;
  }
  sqliteBeginWriteOperation(pParse, row_triggers_exist, pTab->iDb);

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

  /* Initialize the counter of the number of rows deleted, if
  ** we are counting rows.
  */
  if( db->flags & SQLITE_CountRows ){
    sqliteVdbeAddOp(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 && !row_triggers_exist ){
    if( db->flags & SQLITE_CountRows ){
      /* If counting rows deleted, just count the total number of
      ** entries in the table. */
      int endOfLoop = sqliteVdbeMakeLabel(v);
      int addr;
      if( !isView ){
        sqliteVdbeAddOp(v, OP_Integer, pTab->iDb, 0);
        sqliteVdbeAddOp(v, OP_OpenRead, iCur, pTab->tnum);
      }
      sqliteVdbeAddOp(v, OP_Rewind, iCur, sqliteVdbeCurrentAddr(v)+2);
      addr = sqliteVdbeAddOp(v, OP_AddImm, 1, 0);
      sqliteVdbeAddOp(v, OP_Next, iCur, addr);
      sqliteVdbeResolveLabel(v, endOfLoop);
      sqliteVdbeAddOp(v, OP_Close, iCur, 0);
    }
    if( !isView ){
      sqliteVdbeAddOp(v, OP_Clear, pTab->tnum, pTab->iDb);
      for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
        sqliteVdbeAddOp(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{
    /* Begin the database scan
    */
    pWInfo = sqliteWhereBegin(pParse, pTabList, pWhere, 1, 0);
    if( pWInfo==0 ) goto delete_from_cleanup;

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

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

    /* Open the pseudo-table used to store OLD if there are triggers.
    */
    if( row_triggers_exist ){
      sqliteVdbeAddOp(v, OP_OpenPseudo, oldIdx, 0);
    }

    /* 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.
    */
    sqliteVdbeAddOp(v, OP_ListRewind, 0, 0);
    end = sqliteVdbeMakeLabel(v);

    /* This is the beginning of the delete loop when there are
    ** row triggers.
    */
    if( row_triggers_exist ){
      addr = sqliteVdbeAddOp(v, OP_ListRead, 0, end);
      sqliteVdbeAddOp(v, OP_Dup, 0, 0);
      if( !isView ){
        sqliteVdbeAddOp(v, OP_Integer, pTab->iDb, 0);
        sqliteVdbeAddOp(v, OP_OpenRead, iCur, pTab->tnum);
      }
      sqliteVdbeAddOp(v, OP_MoveTo, iCur, 0);

      sqliteVdbeAddOp(v, OP_Recno, iCur, 0);
      sqliteVdbeAddOp(v, OP_RowData, iCur, 0);
      sqliteVdbeAddOp(v, OP_PutIntKey, oldIdx, 0);
      if( !isView ){
        sqliteVdbeAddOp(v, OP_Close, iCur, 0);
      }

      sqliteCodeRowTrigger(pParse, TK_DELETE, 0, TK_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.
      */
      pParse->nTab = iCur + 1;
      sqliteOpenTableAndIndices(pParse, pTab, iCur);

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

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

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

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

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

  /*
  ** Return the number of rows that were deleted.
  */
  if( db->flags & SQLITE_CountRows ){
    sqliteVdbeAddOp(v, OP_ColumnName, 0, 1);
    sqliteVdbeChangeP3(v, -1, "rows deleted", P3_STATIC);
    sqliteVdbeAddOp(v, OP_Callback, 1, 0);
  }

delete_from_cleanup:
  sqliteAuthContextPop(&sContext);
  sqliteSrcListDelete(pTabList);
  sqliteExprDelete(pWhere);
  return;
}
Ejemplo n.º 5
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 sqliteInsert(
  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;             /* VDBE Cursor number for pTab */
  int iCont, iBreak;    /* Beginning and end of the loop over srcTab */
  sqlite *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;     /* Store SELECT results in intermediate table */
  int srcTab;           /* Data comes from this temporary cursor if >=0 */
  int iSelectLoop;      /* Address of code that implements the SELECT */
  int iCleanup;         /* Address of the cleanup code */
  int iInsertBlock;     /* Address of the subroutine used to insert data */
  int iCntMem;          /* Memory cell used for the row counter */
  int isView;           /* True if attempting to insert into a view */

  int row_triggers_exist = 0; /* True if there are FOR EACH ROW triggers */
  int before_triggers;        /* True if there are BEFORE triggers */
  int after_triggers;         /* True if there are AFTER triggers */
  int newIdx = -1;            /* Cursor for the NEW table */

  if( pParse->nErr || sqlite_malloc_failed ) 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 = sqliteSrcListLookup(pParse, pTabList);
  if( pTab==0 ){
    goto insert_cleanup;
  }
  assert( pTab->iDb<db->nDb );
  zDb = db->aDb[pTab->iDb].zName;
  if( sqliteAuthCheck(pParse, SQLITE_INSERT, pTab->zName, 0, zDb) ){
    goto insert_cleanup;
  }

  /* Ensure that:
  *  (a) the table is not read-only, 
  *  (b) that if it is a view then ON INSERT triggers exist
  */
  before_triggers = sqliteTriggersExist(pParse, pTab->pTrigger, TK_INSERT, 
                                       TK_BEFORE, TK_ROW, 0);
  after_triggers = sqliteTriggersExist(pParse, pTab->pTrigger, TK_INSERT,
                                       TK_AFTER, TK_ROW, 0);
  row_triggers_exist = before_triggers || after_triggers;
  isView = pTab->pSelect!=0;
  if( sqliteIsReadOnly(pParse, pTab, before_triggers) ){
    goto insert_cleanup;
  }
  if( pTab==0 ) goto insert_cleanup;

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

  /* Allocate a VDBE
  */
  v = sqliteGetVdbe(pParse);
  if( v==0 ) goto insert_cleanup;
  sqliteBeginWriteOperation(pParse, pSelect || row_triggers_exist, pTab->iDb);

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

  /* 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 = sqliteVdbeAddOp(v, OP_Goto, 0, 0);
    iSelectLoop = sqliteVdbeCurrentAddr(v);
    iInsertBlock = sqliteVdbeMakeLabel(v);
    rc = sqliteSelect(pParse, pSelect, SRT_Subroutine, iInsertBlock, 0,0,0);
    if( rc || pParse->nErr || sqlite_malloc_failed ) goto insert_cleanup;
    iCleanup = sqliteVdbeMakeLabel(v);
    sqliteVdbeAddOp(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( row_triggers_exist ){
      useTempTable = 1;
    }else{
      int addr = sqliteVdbeFindOp(v, OP_OpenRead, pTab->tnum);
      useTempTable = 0;
      if( addr>0 ){
        VdbeOp *pOp = sqliteVdbeGetOp(v, addr-2);
        if( pOp->opcode==OP_Integer && pOp->p1==pTab->iDb ){
          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++;
      sqliteVdbeResolveLabel(v, iInsertBlock);
      sqliteVdbeAddOp(v, OP_MakeRecord, nColumn, 0);
      sqliteVdbeAddOp(v, OP_NewRecno, srcTab, 0);
      sqliteVdbeAddOp(v, OP_Pull, 1, 0);
      sqliteVdbeAddOp(v, OP_PutIntKey, srcTab, 0);
      sqliteVdbeAddOp(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.
      */
      sqliteVdbeChangeP2(v, iInitCode, sqliteVdbeCurrentAddr(v));
      sqliteVdbeAddOp(v, OP_OpenTemp, srcTab, 0);
      sqliteVdbeAddOp(v, OP_Goto, 0, iSelectLoop);
      sqliteVdbeResolveLabel(v, iCleanup);
    }else{
      sqliteVdbeChangeP2(v, iInitCode, sqliteVdbeCurrentAddr(v));
    }
  }else{
    /* This is the case if the data for the INSERT is coming from a VALUES
    ** clause
    */
    SrcList dummy;
    assert( pList!=0 );
    srcTab = -1;
    useTempTable = 0;
    assert( pList );
    nColumn = pList->nExpr;
    dummy.nSrc = 0;
    for(i=0; i<nColumn; i++){
      if( sqliteExprResolveIds(pParse, &dummy, 0, pList->a[i].pExpr) ){
        goto insert_cleanup;
      }
      if( sqliteExprCheck(pParse, pList->a[i].pExpr, 0, 0) ){
        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 ){
    sqliteErrorMsg(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 ){
    sqliteErrorMsg(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( sqliteStrICmp(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( sqliteIsRowid(pColumn->a[i].zName) ){
          keyColumn = i;
        }else{
          sqliteErrorMsg(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( row_triggers_exist ){
    sqliteVdbeAddOp(v, OP_OpenPseudo, newIdx, 0);
  }
    
  /* Initialize the count of rows to be inserted
  */
  if( db->flags & SQLITE_CountRows ){
    iCntMem = pParse->nMem++;
    sqliteVdbeAddOp(v, OP_Integer, 0, 0);
    sqliteVdbeAddOp(v, OP_MemStore, iCntMem, 1);
  }

  /* Open tables and indices if there are no row triggers */
  if( !row_triggers_exist ){
    base = pParse->nTab;
    idx = sqliteOpenTableAndIndices(pParse, pTab, base);
    pParse->nTab += idx;
  }

  /* 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 = sqliteVdbeMakeLabel(v);
    sqliteVdbeAddOp(v, OP_Rewind, srcTab, iBreak);
    iCont = sqliteVdbeCurrentAddr(v);
  }else if( pSelect ){
    sqliteVdbeAddOp(v, OP_Goto, 0, iSelectLoop);
    sqliteVdbeResolveLabel(v, iInsertBlock);
  }

  /* Run the BEFORE and INSTEAD OF triggers, if there are any
  */
  endOfLoop = sqliteVdbeMakeLabel(v);
  if( before_triggers ){

    /* 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 ){
      sqliteVdbeAddOp(v, OP_Integer, -1, 0);
    }else if( useTempTable ){
      sqliteVdbeAddOp(v, OP_Column, srcTab, keyColumn);
    }else if( pSelect ){
      sqliteVdbeAddOp(v, OP_Dup, nColumn - keyColumn - 1, 1);
    }else{
      sqliteExprCode(pParse, pList->a[keyColumn].pExpr);
      sqliteVdbeAddOp(v, OP_NotNull, -1, sqliteVdbeCurrentAddr(v)+3);
      sqliteVdbeAddOp(v, OP_Pop, 1, 0);
      sqliteVdbeAddOp(v, OP_Integer, -1, 0);
      sqliteVdbeAddOp(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 ){
        sqliteVdbeOp3(v, OP_String, 0, 0, pTab->aCol[i].zDflt, P3_STATIC);
      }else if( useTempTable ){
        sqliteVdbeAddOp(v, OP_Column, srcTab, j); 
      }else if( pSelect ){
        sqliteVdbeAddOp(v, OP_Dup, nColumn-j-1, 1);
      }else{
        sqliteExprCode(pParse, pList->a[j].pExpr);
      }
    }
    sqliteVdbeAddOp(v, OP_MakeRecord, pTab->nCol, 0);
    sqliteVdbeAddOp(v, OP_PutIntKey, newIdx, 0);

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

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

  /* Push the record number for the new entry onto the stack.  The
  ** record number is a randomly generate integer created by NewRecno
  ** 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 ){
        sqliteVdbeAddOp(v, OP_Column, srcTab, keyColumn);
      }else if( pSelect ){
        sqliteVdbeAddOp(v, OP_Dup, nColumn - keyColumn - 1, 1);
      }else{
        sqliteExprCode(pParse, pList->a[keyColumn].pExpr);
      }
      /* If the PRIMARY KEY expression is NULL, then use OP_NewRecno
      ** to generate a unique primary key value.
      */
      sqliteVdbeAddOp(v, OP_NotNull, -1, sqliteVdbeCurrentAddr(v)+3);
      sqliteVdbeAddOp(v, OP_Pop, 1, 0);
      sqliteVdbeAddOp(v, OP_NewRecno, base, 0);
      sqliteVdbeAddOp(v, OP_MustBeInt, 0, 0);
    }else{
      sqliteVdbeAddOp(v, OP_NewRecno, base, 0);
    }

    /* 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. */
        sqliteVdbeAddOp(v, OP_String, 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 ){
        sqliteVdbeOp3(v, OP_String, 0, 0, pTab->aCol[i].zDflt, P3_STATIC);
      }else if( useTempTable ){
        sqliteVdbeAddOp(v, OP_Column, srcTab, j); 
      }else if( pSelect ){
        sqliteVdbeAddOp(v, OP_Dup, i+nColumn-j, 1);
      }else{
        sqliteExprCode(pParse, pList->a[j].pExpr);
      }
    }

    /* Generate code to check constraints and generate index keys and
    ** do the insertion.
    */
    sqliteGenerateConstraintChecks(pParse, pTab, base, 0, keyColumn>=0,
                                   0, onError, endOfLoop);
    sqliteCompleteInsertion(pParse, pTab, base, 0,0,0,
                            after_triggers ? newIdx : -1);
  }

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

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

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

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

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

  sqliteVdbeAddOp(v, OP_SetCounts, 0, 0);
  sqliteEndWriteOperation(pParse);

  /*
  ** Return the number of rows inserted.
  */
  if( db->flags & SQLITE_CountRows ){
    sqliteVdbeOp3(v, OP_ColumnName, 0, 1, "rows inserted", P3_STATIC);
    sqliteVdbeAddOp(v, OP_MemLoad, iCntMem, 0);
    sqliteVdbeAddOp(v, OP_Callback, 1, 0);
  }

insert_cleanup:
  sqliteSrcListDelete(pTabList);
  if( pList ) sqliteExprListDelete(pList);
  if( pSelect ) sqliteSelectDelete(pSelect);
  sqliteIdListDelete(pColumn);
}
Ejemplo n.º 6
0
/*
** This routine walks an expression tree and resolves references to
** table columns.  Nodes of the form ID.ID or ID resolve into an
** index to the table in the table list and a column offset.  The 
** Expr.opcode for such nodes is changed to TK_COLUMN.  The Expr.iTable
** value is changed to the index of the referenced table in pTabList
** plus the "base" value.  The base value will ultimately become the
** VDBE cursor number for a cursor that is pointing into the referenced
** table.  The Expr.iColumn value is changed to the index of the column 
** of the referenced table.  The Expr.iColumn value for the special
** ROWID column is -1.  Any INTEGER PRIMARY KEY column is tried as an
** alias for ROWID.
**
** We also check for instances of the IN operator.  IN comes in two
** forms:
**
**           expr IN (exprlist)
** and
**           expr IN (SELECT ...)
**
** The first form is handled by creating a set holding the list
** of allowed values.  The second form causes the SELECT to generate 
** a temporary table.
**
** This routine also looks for scalar SELECTs that are part of an expression.
** If it finds any, it generates code to write the value of that select
** into a memory cell.
**
** Unknown columns or tables provoke an error.  The function returns
** the number of errors seen and leaves an error message on pParse->zErrMsg.
*/
int sqliteExprResolveIds(
  Parse *pParse,     /* The parser context */
  SrcList *pSrcList, /* List of tables used to resolve column names */
  ExprList *pEList,  /* List of expressions used to resolve "AS" */
  Expr *pExpr        /* The expression to be analyzed. */
){
  int i;

  if( pExpr==0 || pSrcList==0 ) return 0;
  for(i=0; i<pSrcList->nSrc; i++){
    assert( pSrcList->a[i].iCursor>=0 && pSrcList->a[i].iCursor<pParse->nTab );
  }
  switch( pExpr->op ){
    /* Double-quoted strings (ex: "abc") are used as identifiers if
    ** possible.  Otherwise they remain as strings.  Single-quoted
    ** strings (ex: 'abc') are always string literals.
    */
    case TK_STRING: {
      if( pExpr->token.z[0]=='\'' ) break;
      /* Fall thru into the TK_ID case if this is a double-quoted string */
    }
    /* A lone identifier is the name of a columnd.
    */
    case TK_ID: {
      if( lookupName(pParse, 0, 0, &pExpr->token, pSrcList, pEList, pExpr) ){
        return 1;
      }
      break; 
    }
  
    /* A table name and column name:     ID.ID
    ** Or a database, table and column:  ID.ID.ID
    */
    case TK_DOT: {
      Token *pColumn;
      Token *pTable;
      Token *pDb;
      Expr *pRight;

      pRight = pExpr->pRight;
      if( pRight->op==TK_ID ){
        pDb = 0;
        pTable = &pExpr->pLeft->token;
        pColumn = &pRight->token;
      }else{
        assert( pRight->op==TK_DOT );
        pDb = &pExpr->pLeft->token;
        pTable = &pRight->pLeft->token;
        pColumn = &pRight->pRight->token;
      }
      if( lookupName(pParse, pDb, pTable, pColumn, pSrcList, 0, pExpr) ){
        return 1;
      }
      break;
    }

    case TK_IN: {
      Vdbe *v = sqliteGetVdbe(pParse);
      if( v==0 ) return 1;
      if( sqliteExprResolveIds(pParse, pSrcList, pEList, pExpr->pLeft) ){
        return 1;
      }
      if( pExpr->pSelect ){
        /* Case 1:     expr IN (SELECT ...)
        **
        ** Generate code to write the results of the select into a temporary
        ** table.  The cursor number of the temporary table has already
        ** been put in iTable by sqliteExprResolveInSelect().
        */
        pExpr->iTable = pParse->nTab++;
        sqliteVdbeAddOp(v, OP_OpenTemp, pExpr->iTable, 1);
        sqliteSelect(pParse, pExpr->pSelect, SRT_Set, pExpr->iTable, 0,0,0);
      }else if( pExpr->pList ){
        /* Case 2:     expr IN (exprlist)
        **
        ** Create a set to put the exprlist values in.  The Set id is stored
        ** in iTable.
        */
        int i, iSet;
        for(i=0; i<pExpr->pList->nExpr; i++){
          Expr *pE2 = pExpr->pList->a[i].pExpr;
          if( !sqliteExprIsConstant(pE2) ){
            sqliteErrorMsg(pParse,
              "right-hand side of IN operator must be constant");
            return 1;
          }
          if( sqliteExprCheck(pParse, pE2, 0, 0) ){
            return 1;
          }
        }
        iSet = pExpr->iTable = pParse->nSet++;
        for(i=0; i<pExpr->pList->nExpr; i++){
          Expr *pE2 = pExpr->pList->a[i].pExpr;
          switch( pE2->op ){
            case TK_FLOAT:
            case TK_INTEGER:
            case TK_STRING: {
              int addr;
              assert( pE2->token.z );
              addr = sqliteVdbeOp3(v, OP_SetInsert, iSet, 0,
                                  pE2->token.z, pE2->token.n);
              sqliteVdbeDequoteP3(v, addr);
              break;
            }
            default: {
              sqliteExprCode(pParse, pE2);
              sqliteVdbeAddOp(v, OP_SetInsert, iSet, 0);
              break;
            }
          }
        }
      }
      break;
    }

    case TK_SELECT: {
      /* This has to be a scalar SELECT.  Generate code to put the
      ** value of this select in a memory cell and record the number
      ** of the memory cell in iColumn.
      */
      pExpr->iColumn = pParse->nMem++;
      if( sqliteSelect(pParse, pExpr->pSelect, SRT_Mem, pExpr->iColumn,0,0,0) ){
        return 1;
      }
      break;
    }

    /* For all else, just recursively walk the tree */
    default: {
      if( pExpr->pLeft
      && sqliteExprResolveIds(pParse, pSrcList, pEList, pExpr->pLeft) ){
        return 1;
      }
      if( pExpr->pRight 
      && sqliteExprResolveIds(pParse, pSrcList, pEList, pExpr->pRight) ){
        return 1;
      }
      if( pExpr->pList ){
        int i;
        ExprList *pList = pExpr->pList;
        for(i=0; i<pList->nExpr; i++){
          Expr *pArg = pList->a[i].pExpr;
          if( sqliteExprResolveIds(pParse, pSrcList, pEList, pArg) ){
            return 1;
          }
        }
      }
    }
  }
  return 0;
}