示例#1
0
static int sqliteCompileBlock(Parse *pParse, Block *b){
  Vdbe *v = sqliteGetVdbe(pParse);
  Block *saveCurBlock;
  int i, handler = 0;

  saveCurBlock = pParse->pCurrentBlock;
  pParse->pCurrentBlock = b;
  DbSetProperty(pParse->db, 0, DB_Cookie);

  b->nExit = sqliteVdbeMakeLabel(v);
	if( b->pExList ) {
		handler = sqliteVdbeMakeLabel(v);
    sqliteVdbeAddOp(v, OP_NewHandler, 0, handler);
	}
  for(i=0; i<b->nVar; i++) {
	  if( b->aVar[i].pDflt!=0 ) {
	    Expr *pExpr = b->aVar[i].pDflt;
      if( sqliteExprProcResolve(pParse, b, pExpr) ){
        return 1;
	    }
      if( sqliteExprCheck(pParse, pExpr, 0, 0) ){
        return 1;
	    }
      sqliteExprCode(pParse, pExpr);
      sqliteVdbeAddOp(v, OP_MemStore, b->aVar[i].mVar , 1);
    }
  }
  if( sqliteCompileList(pParse, b, b->pStList, 0, 0) ){
    return 1;
  }
  if( b->pExList ) {
    sqliteVdbeAddOp(v, OP_Goto, 0, b->nExit);
		sqliteVdbeResolveLabel(v, handler);
		if( sqliteCompileHandlers(pParse, b, b->pExList) ){
      return 1;
		}
  }
  sqliteVdbeResolveLabel(v, b->nExit);
	if( b->pExList && b->pParent!=0 ) {
    sqliteVdbeAddOp(v, OP_PrevHandler, 0, 0);
	}
  /* if we end with 'goto next' (last stmt is a return), remove it */
//  if( v->aOp[v->nOp-1].opcode==OP_Goto && v->aOp[v->nOp-1].p2==v->nOp ) {
//    v->nOp--;
//  }
  pParse->pCurrentBlock = saveCurBlock;
  return 0;
}
示例#2
0
static int sqliteCompileCall(
  Parse *pParse,
  Token *pName,
  ExprList *pEList
) {
  char *zName = 0;
  Vdbe *v = sqliteGetVdbe(pParse);
  Block *b = pParse->pCurrentBlock;
  Object * pObj = 0;
  sqlite *db = pParse->db;
  int i, nActual = 0;

  /* Check that the object exist & get its Object pointer*/
  zName = sqliteStrNDup(pName->z, pName->n);
  sqliteDequote(zName);
  pObj = sqliteHashFind(&(db->aDb[0].objectHash), zName,pName->n+1);
  if( !pObj ){
    sqliteErrorMsg(pParse, "object %T not found", pName);
    goto proc_cleanup;
  }
  if( pEList ) {
    nActual = pEList->nExpr;
  }
  if( pObj->nParam!=nActual ) {
  	sqliteErrorMsg(pParse, "bad parameter count for object %T", pName);
    goto proc_cleanup;
  }

  for(i=0; i<nActual; i++) {
	  Expr *pExpr = pEList->a[i].pExpr;
    if( sqliteExprProcResolve(pParse, b, pExpr) ){
      goto proc_cleanup;
    }
    if( sqliteExprCheck(pParse, pExpr, 0, 0) ){
      goto proc_cleanup;
    }
    sqliteExprCode(pParse, pExpr);
  }
  sqliteVdbeOp3(v, OP_Exec, nActual, 0, zName, P3_DYNAMIC);
  return 0;

proc_cleanup:
  sqliteFree(zName);
  return 1;
}
示例#3
0
/*
** Generate code that pushes the value of every element of the given
** expression list onto the stack.  If the includeTypes flag is true,
** then also push a string that is the datatype of each element onto
** the stack after the value.
**
** Return the number of elements pushed onto the stack.
*/
int sqliteExprCodeExprList(
  Parse *pParse,     /* Parsing context */
  ExprList *pList,   /* The expression list to be coded */
  int includeTypes   /* TRUE to put datatypes on the stack too */
){
  struct ExprList_item *pItem;
  int i, n;
  Vdbe *v;
  if( pList==0 ) return 0;
  v = sqliteGetVdbe(pParse);
  n = pList->nExpr;
  for(pItem=pList->a, i=0; i<n; i++, pItem++){
    sqliteExprCode(pParse, pItem->pExpr);
    if( includeTypes ){
      sqliteVdbeOp3(v, OP_String, 0, 0, 
         sqliteExprType(pItem->pExpr)==SQLITE_SO_NUM ? "numeric" : "text",
         P3_STATIC);
    }
  }
  return includeTypes ? n*2 : n;
}
示例#4
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;
}
示例#5
0
文件: where.c 项目: kennyb/php-broken
/*
** Generate the beginning of the loop used for WHERE clause processing.
** The return value is a pointer to an (opaque) structure that contains
** information needed to terminate the loop.  Later, the calling routine
** should invoke sqliteWhereEnd() with the return value of this function
** in order to complete the WHERE clause processing.
**
** If an error occurs, this routine returns NULL.
**
** The basic idea is to do a nested loop, one loop for each table in
** the FROM clause of a select.  (INSERT and UPDATE statements are the
** same as a SELECT with only a single table in the FROM clause.)  For
** example, if the SQL is this:
**
**       SELECT * FROM t1, t2, t3 WHERE ...;
**
** Then the code generated is conceptually like the following:
**
**      foreach row1 in t1 do       \    Code generated
**        foreach row2 in t2 do      |-- by sqliteWhereBegin()
**          foreach row3 in t3 do   /
**            ...
**          end                     \    Code generated
**        end                        |-- by sqliteWhereEnd()
**      end                         /
**
** There are Btree cursors associated with each table.  t1 uses cursor
** number pTabList->a[0].iCursor.  t2 uses the cursor pTabList->a[1].iCursor.
** And so forth.  This routine generates code to open those VDBE cursors
** and sqliteWhereEnd() generates the code to close them.
**
** If the WHERE clause is empty, the foreach loops must each scan their
** entire tables.  Thus a three-way join is an O(N^3) operation.  But if
** the tables have indices and there are terms in the WHERE clause that
** refer to those indices, a complete table scan can be avoided and the
** code will run much faster.  Most of the work of this routine is checking
** to see if there are indices that can be used to speed up the loop.
**
** Terms of the WHERE clause are also used to limit which rows actually
** make it to the "..." in the middle of the loop.  After each "foreach",
** terms of the WHERE clause that use only terms in that loop and outer
** loops are evaluated and if false a jump is made around all subsequent
** inner loops (or around the "..." if the test occurs within the inner-
** most loop)
**
** OUTER JOINS
**
** An outer join of tables t1 and t2 is conceptally coded as follows:
**
**    foreach row1 in t1 do
**      flag = 0
**      foreach row2 in t2 do
**        start:
**          ...
**          flag = 1
**      end
**      if flag==0 then
**        move the row2 cursor to a null row
**        goto start
**      fi
**    end
**
** ORDER BY CLAUSE PROCESSING
**
** *ppOrderBy is a pointer to the ORDER BY clause of a SELECT statement,
** if there is one.  If there is no ORDER BY clause or if this routine
** is called from an UPDATE or DELETE statement, then ppOrderBy is NULL.
**
** If an index can be used so that the natural output order of the table
** scan is correct for the ORDER BY clause, then that index is used and
** *ppOrderBy is set to NULL.  This is an optimization that prevents an
** unnecessary sort of the result set if an index appropriate for the
** ORDER BY clause already exists.
**
** If the where clause loops cannot be arranged to provide the correct
** output order, then the *ppOrderBy is unchanged.
*/
WhereInfo *sqliteWhereBegin(
  Parse *pParse,       /* The parser context */
  SrcList *pTabList,   /* A list of all tables to be scanned */
  Expr *pWhere,        /* The WHERE clause */
  int pushKey,         /* If TRUE, leave the table key on the stack */
  ExprList **ppOrderBy /* An ORDER BY clause, or NULL */
){
  int i;                     /* Loop counter */
  WhereInfo *pWInfo;         /* Will become the return value of this function */
  Vdbe *v = pParse->pVdbe;   /* The virtual database engine */
  int brk, cont = 0;         /* Addresses used during code generation */
  int nExpr;           /* Number of subexpressions in the WHERE clause */
  int loopMask;        /* One bit set for each outer loop */
  int haveKey;         /* True if KEY is on the stack */
  ExprMaskSet maskSet; /* The expression mask set */
  int iDirectEq[32];   /* Term of the form ROWID==X for the N-th table */
  int iDirectLt[32];   /* Term of the form ROWID<X or ROWID<=X */
  int iDirectGt[32];   /* Term of the form ROWID>X or ROWID>=X */
  ExprInfo aExpr[101]; /* The WHERE clause is divided into these expressions */

  /* pushKey is only allowed if there is a single table (as in an INSERT or
  ** UPDATE statement)
  */
  assert( pushKey==0 || pTabList->nSrc==1 );

  /* Split the WHERE clause into separate subexpressions where each
  ** subexpression is separated by an AND operator.  If the aExpr[]
  ** array fills up, the last entry might point to an expression which
  ** contains additional unfactored AND operators.
  */
  initMaskSet(&maskSet);
  memset(aExpr, 0, sizeof(aExpr));
  nExpr = exprSplit(ARRAYSIZE(aExpr), aExpr, pWhere);
  if( nExpr==ARRAYSIZE(aExpr) ){
    sqliteErrorMsg(pParse, "WHERE clause too complex - no more "
       "than %d terms allowed", (int)ARRAYSIZE(aExpr)-1);
    return 0;
  }
  
  /* Allocate and initialize the WhereInfo structure that will become the
  ** return value.
  */
  pWInfo = sqliteMalloc( sizeof(WhereInfo) + pTabList->nSrc*sizeof(WhereLevel));
  if( sqlite_malloc_failed ){
    sqliteFree(pWInfo);
    return 0;
  }
  pWInfo->pParse = pParse;
  pWInfo->pTabList = pTabList;
  pWInfo->peakNTab = pWInfo->savedNTab = pParse->nTab;
  pWInfo->iBreak = sqliteVdbeMakeLabel(v);

  /* Special case: a WHERE clause that is constant.  Evaluate the
  ** expression and either jump over all of the code or fall thru.
  */
  if( pWhere && (pTabList->nSrc==0 || sqliteExprIsConstant(pWhere)) ){
    sqliteExprIfFalse(pParse, pWhere, pWInfo->iBreak, 1);
    pWhere = 0;
  }

  /* Analyze all of the subexpressions.
  */
  for(i=0; i<nExpr; i++){
    exprAnalyze(&maskSet, &aExpr[i]);

    /* If we are executing a trigger body, remove all references to
    ** new.* and old.* tables from the prerequisite masks.
    */
    if( pParse->trigStack ){
      int x;
      if( (x = pParse->trigStack->newIdx) >= 0 ){
        int mask = ~getMask(&maskSet, x);
        aExpr[i].prereqRight &= mask;
        aExpr[i].prereqLeft &= mask;
        aExpr[i].prereqAll &= mask;
      }
      if( (x = pParse->trigStack->oldIdx) >= 0 ){
        int mask = ~getMask(&maskSet, x);
        aExpr[i].prereqRight &= mask;
        aExpr[i].prereqLeft &= mask;
        aExpr[i].prereqAll &= mask;
      }
    }
  }

  /* Figure out what index to use (if any) for each nested loop.
  ** Make pWInfo->a[i].pIdx point to the index to use for the i-th nested
  ** loop where i==0 is the outer loop and i==pTabList->nSrc-1 is the inner
  ** loop. 
  **
  ** If terms exist that use the ROWID of any table, then set the
  ** iDirectEq[], iDirectLt[], or iDirectGt[] elements for that table
  ** to the index of the term containing the ROWID.  We always prefer
  ** to use a ROWID which can directly access a table rather than an
  ** index which requires reading an index first to get the rowid then
  ** doing a second read of the actual database table.
  **
  ** Actually, if there are more than 32 tables in the join, only the
  ** first 32 tables are candidates for indices.  This is (again) due
  ** to the limit of 32 bits in an integer bitmask.
  */
  loopMask = 0;
  for(i=0; i<pTabList->nSrc && i<ARRAYSIZE(iDirectEq); i++){
    int j;
    int iCur = pTabList->a[i].iCursor;    /* The cursor for this table */
    int mask = getMask(&maskSet, iCur);   /* Cursor mask for this table */
    Table *pTab = pTabList->a[i].pTab;
    Index *pIdx;
    Index *pBestIdx = 0;
    int bestScore = 0;

    /* Check to see if there is an expression that uses only the
    ** ROWID field of this table.  For terms of the form ROWID==expr
    ** set iDirectEq[i] to the index of the term.  For terms of the
    ** form ROWID<expr or ROWID<=expr set iDirectLt[i] to the term index.
    ** For terms like ROWID>expr or ROWID>=expr set iDirectGt[i].
    **
    ** (Added:) Treat ROWID IN expr like ROWID=expr.
    */
    pWInfo->a[i].iCur = -1;
    iDirectEq[i] = -1;
    iDirectLt[i] = -1;
    iDirectGt[i] = -1;
    for(j=0; j<nExpr; j++){
      if( aExpr[j].idxLeft==iCur && aExpr[j].p->pLeft->iColumn<0
            && (aExpr[j].prereqRight & loopMask)==aExpr[j].prereqRight ){
        switch( aExpr[j].p->op ){
          case TK_IN:
          case TK_EQ: iDirectEq[i] = j; break;
          case TK_LE:
          case TK_LT: iDirectLt[i] = j; break;
          case TK_GE:
          case TK_GT: iDirectGt[i] = j;  break;
        }
      }
      if( aExpr[j].idxRight==iCur && aExpr[j].p->pRight->iColumn<0
            && (aExpr[j].prereqLeft & loopMask)==aExpr[j].prereqLeft ){
        switch( aExpr[j].p->op ){
          case TK_EQ: iDirectEq[i] = j;  break;
          case TK_LE:
          case TK_LT: iDirectGt[i] = j;  break;
          case TK_GE:
          case TK_GT: iDirectLt[i] = j;  break;
        }
      }
    }
    if( iDirectEq[i]>=0 ){
      loopMask |= mask;
      pWInfo->a[i].pIdx = 0;
      continue;
    }

    /* Do a search for usable indices.  Leave pBestIdx pointing to
    ** the "best" index.  pBestIdx is left set to NULL if no indices
    ** are usable.
    **
    ** The best index is determined as follows.  For each of the
    ** left-most terms that is fixed by an equality operator, add
    ** 8 to the score.  The right-most term of the index may be
    ** constrained by an inequality.  Add 1 if for an "x<..." constraint
    ** and add 2 for an "x>..." constraint.  Chose the index that
    ** gives the best score.
    **
    ** This scoring system is designed so that the score can later be
    ** used to determine how the index is used.  If the score&7 is 0
    ** then all constraints are equalities.  If score&1 is not 0 then
    ** there is an inequality used as a termination key.  (ex: "x<...")
    ** If score&2 is not 0 then there is an inequality used as the
    ** start key.  (ex: "x>...").  A score or 4 is the special case
    ** of an IN operator constraint.  (ex:  "x IN ...").
    **
    ** The IN operator (as in "<expr> IN (...)") is treated the same as
    ** an equality comparison except that it can only be used on the
    ** left-most column of an index and other terms of the WHERE clause
    ** cannot be used in conjunction with the IN operator to help satisfy
    ** other columns of the index.
    */
    for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
      int eqMask = 0;  /* Index columns covered by an x=... term */
      int ltMask = 0;  /* Index columns covered by an x<... term */
      int gtMask = 0;  /* Index columns covered by an x>... term */
      int inMask = 0;  /* Index columns covered by an x IN .. term */
      int nEq, m, score;

      if( pIdx->nColumn>32 ) continue;  /* Ignore indices too many columns */
      for(j=0; j<nExpr; j++){
        if( aExpr[j].idxLeft==iCur 
             && (aExpr[j].prereqRight & loopMask)==aExpr[j].prereqRight ){
          int iColumn = aExpr[j].p->pLeft->iColumn;
          int k;
          for(k=0; k<pIdx->nColumn; k++){
            if( pIdx->aiColumn[k]==iColumn ){
              switch( aExpr[j].p->op ){
                case TK_IN: {
                  if( k==0 ) inMask |= 1;
                  break;
                }
                case TK_EQ: {
                  eqMask |= 1<<k;
                  break;
                }
                case TK_LE:
                case TK_LT: {
                  ltMask |= 1<<k;
                  break;
                }
                case TK_GE:
                case TK_GT: {
                  gtMask |= 1<<k;
                  break;
                }
                default: {
                  /* CANT_HAPPEN */
                  assert( 0 );
                  break;
                }
              }
              break;
            }
          }
        }
        if( aExpr[j].idxRight==iCur 
             && (aExpr[j].prereqLeft & loopMask)==aExpr[j].prereqLeft ){
          int iColumn = aExpr[j].p->pRight->iColumn;
          int k;
          for(k=0; k<pIdx->nColumn; k++){
            if( pIdx->aiColumn[k]==iColumn ){
              switch( aExpr[j].p->op ){
                case TK_EQ: {
                  eqMask |= 1<<k;
                  break;
                }
                case TK_LE:
                case TK_LT: {
                  gtMask |= 1<<k;
                  break;
                }
                case TK_GE:
                case TK_GT: {
                  ltMask |= 1<<k;
                  break;
                }
                default: {
                  /* CANT_HAPPEN */
                  assert( 0 );
                  break;
                }
              }
              break;
            }
          }
        }
      }

      /* The following loop ends with nEq set to the number of columns
      ** on the left of the index with == constraints.
      */
      for(nEq=0; nEq<pIdx->nColumn; nEq++){
        m = (1<<(nEq+1))-1;
        if( (m & eqMask)!=m ) break;
      }
      score = nEq*8;   /* Base score is 8 times number of == constraints */
      m = 1<<nEq;
      if( m & ltMask ) score++;    /* Increase score for a < constraint */
      if( m & gtMask ) score+=2;   /* Increase score for a > constraint */
      if( score==0 && inMask ) score = 4;  /* Default score for IN constraint */
      if( score>bestScore ){
        pBestIdx = pIdx;
        bestScore = score;
      }
    }
    pWInfo->a[i].pIdx = pBestIdx;
    pWInfo->a[i].score = bestScore;
    pWInfo->a[i].bRev = 0;
    loopMask |= mask;
    if( pBestIdx ){
      pWInfo->a[i].iCur = pParse->nTab++;
      pWInfo->peakNTab = pParse->nTab;
    }
  }

  /* Check to see if the ORDER BY clause is or can be satisfied by the
  ** use of an index on the first table.
  */
  if( ppOrderBy && *ppOrderBy && pTabList->nSrc>0 ){
     Index *pSortIdx;
     Index *pIdx;
     Table *pTab;
     int bRev = 0;

     pTab = pTabList->a[0].pTab;
     pIdx = pWInfo->a[0].pIdx;
     if( pIdx && pWInfo->a[0].score==4 ){
       /* If there is already an IN index on the left-most table,
       ** it will not give the correct sort order.
       ** So, pretend that no suitable index is found.
       */
       pSortIdx = 0;
     }else if( iDirectEq[0]>=0 || iDirectLt[0]>=0 || iDirectGt[0]>=0 ){
       /* If the left-most column is accessed using its ROWID, then do
       ** not try to sort by index.
       */
       pSortIdx = 0;
     }else{
       int nEqCol = (pWInfo->a[0].score+4)/8;
       pSortIdx = findSortingIndex(pTab, pTabList->a[0].iCursor, 
                                   *ppOrderBy, pIdx, nEqCol, &bRev);
     }
     if( pSortIdx && (pIdx==0 || pIdx==pSortIdx) ){
       if( pIdx==0 ){
         pWInfo->a[0].pIdx = pSortIdx;
         pWInfo->a[0].iCur = pParse->nTab++;
         pWInfo->peakNTab = pParse->nTab;
       }
       pWInfo->a[0].bRev = bRev;
       *ppOrderBy = 0;
     }
  }

  /* Open all tables in the pTabList and all indices used by those tables.
  */
  for(i=0; i<pTabList->nSrc; i++){
    Table *pTab;
    Index *pIx;

    pTab = pTabList->a[i].pTab;
    if( pTab->isTransient || pTab->pSelect ) continue;
    sqliteVdbeAddOp(v, OP_Integer, pTab->iDb, 0);
    sqliteVdbeOp3(v, OP_OpenRead, pTabList->a[i].iCursor, pTab->tnum,
                     pTab->zName, P3_STATIC);
    sqliteCodeVerifySchema(pParse, pTab->iDb);
    if( (pIx = pWInfo->a[i].pIdx)!=0 ){
      sqliteVdbeAddOp(v, OP_Integer, pIx->iDb, 0);
      sqliteVdbeOp3(v, OP_OpenRead, pWInfo->a[i].iCur, pIx->tnum, pIx->zName,0);
    }
  }

  /* Generate the code to do the search
  */
  loopMask = 0;
  for(i=0; i<pTabList->nSrc; i++){
    int j, k;
    int iCur = pTabList->a[i].iCursor;
    Index *pIdx;
    WhereLevel *pLevel = &pWInfo->a[i];

    /* If this is the right table of a LEFT OUTER JOIN, allocate and
    ** initialize a memory cell that records if this table matches any
    ** row of the left table of the join.
    */
    if( i>0 && (pTabList->a[i-1].jointype & JT_LEFT)!=0 ){
      if( !pParse->nMem ) pParse->nMem++;
      pLevel->iLeftJoin = pParse->nMem++;
      sqliteVdbeAddOp(v, OP_String, 0, 0);
      sqliteVdbeAddOp(v, OP_MemStore, pLevel->iLeftJoin, 1);
    }

    pIdx = pLevel->pIdx;
    pLevel->inOp = OP_Noop;
    if( i<ARRAYSIZE(iDirectEq) && iDirectEq[i]>=0 ){
      /* Case 1:  We can directly reference a single row using an
      **          equality comparison against the ROWID field.  Or
      **          we reference multiple rows using a "rowid IN (...)"
      **          construct.
      */
      k = iDirectEq[i];
      assert( k<nExpr );
      assert( aExpr[k].p!=0 );
      assert( aExpr[k].idxLeft==iCur || aExpr[k].idxRight==iCur );
      brk = pLevel->brk = sqliteVdbeMakeLabel(v);
      if( aExpr[k].idxLeft==iCur ){
        Expr *pX = aExpr[k].p;
        if( pX->op!=TK_IN ){
          sqliteExprCode(pParse, aExpr[k].p->pRight);
        }else if( pX->pList ){
          sqliteVdbeAddOp(v, OP_SetFirst, pX->iTable, brk);
          pLevel->inOp = OP_SetNext;
          pLevel->inP1 = pX->iTable;
          pLevel->inP2 = sqliteVdbeCurrentAddr(v);
        }else{
          assert( pX->pSelect );
          sqliteVdbeAddOp(v, OP_Rewind, pX->iTable, brk);
          sqliteVdbeAddOp(v, OP_KeyAsData, pX->iTable, 1);
          pLevel->inP2 = sqliteVdbeAddOp(v, OP_FullKey, pX->iTable, 0);
          pLevel->inOp = OP_Next;
          pLevel->inP1 = pX->iTable;
        }
      }else{
        sqliteExprCode(pParse, aExpr[k].p->pLeft);
      }
      disableTerm(pLevel, &aExpr[k].p);
      cont = pLevel->cont = sqliteVdbeMakeLabel(v);
      sqliteVdbeAddOp(v, OP_MustBeInt, 1, brk);
      haveKey = 0;
      sqliteVdbeAddOp(v, OP_NotExists, iCur, brk);
      pLevel->op = OP_Noop;
    }else if( pIdx!=0 && pLevel->score>0 && pLevel->score%4==0 ){
      /* Case 2:  There is an index and all terms of the WHERE clause that
      **          refer to the index use the "==" or "IN" operators.
      */
      int start;
      int testOp;
      int nColumn = (pLevel->score+4)/8;
      brk = pLevel->brk = sqliteVdbeMakeLabel(v);
      for(j=0; j<nColumn; j++){
        for(k=0; k<nExpr; k++){
          Expr *pX = aExpr[k].p;
          if( pX==0 ) continue;
          if( aExpr[k].idxLeft==iCur
             && (aExpr[k].prereqRight & loopMask)==aExpr[k].prereqRight 
             && pX->pLeft->iColumn==pIdx->aiColumn[j]
          ){
            if( pX->op==TK_EQ ){
              sqliteExprCode(pParse, pX->pRight);
              disableTerm(pLevel, &aExpr[k].p);
              break;
            }
            if( pX->op==TK_IN && nColumn==1 ){
              if( pX->pList ){
                sqliteVdbeAddOp(v, OP_SetFirst, pX->iTable, brk);
                pLevel->inOp = OP_SetNext;
                pLevel->inP1 = pX->iTable;
                pLevel->inP2 = sqliteVdbeCurrentAddr(v);
              }else{
                assert( pX->pSelect );
                sqliteVdbeAddOp(v, OP_Rewind, pX->iTable, brk);
                sqliteVdbeAddOp(v, OP_KeyAsData, pX->iTable, 1);
                pLevel->inP2 = sqliteVdbeAddOp(v, OP_FullKey, pX->iTable, 0);
                pLevel->inOp = OP_Next;
                pLevel->inP1 = pX->iTable;
              }
              disableTerm(pLevel, &aExpr[k].p);
              break;
            }
          }
          if( aExpr[k].idxRight==iCur
             && aExpr[k].p->op==TK_EQ
             && (aExpr[k].prereqLeft & loopMask)==aExpr[k].prereqLeft
             && aExpr[k].p->pRight->iColumn==pIdx->aiColumn[j]
          ){
            sqliteExprCode(pParse, aExpr[k].p->pLeft);
            disableTerm(pLevel, &aExpr[k].p);
            break;
          }
        }
      }
      pLevel->iMem = pParse->nMem++;
      cont = pLevel->cont = sqliteVdbeMakeLabel(v);
      sqliteVdbeAddOp(v, OP_NotNull, -nColumn, sqliteVdbeCurrentAddr(v)+3);
      sqliteVdbeAddOp(v, OP_Pop, nColumn, 0);
      sqliteVdbeAddOp(v, OP_Goto, 0, brk);
      sqliteVdbeAddOp(v, OP_MakeKey, nColumn, 0);
      sqliteAddIdxKeyType(v, pIdx);
      if( nColumn==pIdx->nColumn || pLevel->bRev ){
        sqliteVdbeAddOp(v, OP_MemStore, pLevel->iMem, 0);
        testOp = OP_IdxGT;
      }else{
        sqliteVdbeAddOp(v, OP_Dup, 0, 0);
        sqliteVdbeAddOp(v, OP_IncrKey, 0, 0);
        sqliteVdbeAddOp(v, OP_MemStore, pLevel->iMem, 1);
        testOp = OP_IdxGE;
      }
      if( pLevel->bRev ){
        /* Scan in reverse order */
        sqliteVdbeAddOp(v, OP_IncrKey, 0, 0);
        sqliteVdbeAddOp(v, OP_MoveLt, pLevel->iCur, brk);
        start = sqliteVdbeAddOp(v, OP_MemLoad, pLevel->iMem, 0);
        sqliteVdbeAddOp(v, OP_IdxLT, pLevel->iCur, brk);
        pLevel->op = OP_Prev;
      }else{
        /* Scan in the forward order */
        sqliteVdbeAddOp(v, OP_MoveTo, pLevel->iCur, brk);
        start = sqliteVdbeAddOp(v, OP_MemLoad, pLevel->iMem, 0);
        sqliteVdbeAddOp(v, testOp, pLevel->iCur, brk);
        pLevel->op = OP_Next;
      }
      sqliteVdbeAddOp(v, OP_RowKey, pLevel->iCur, 0);
      sqliteVdbeAddOp(v, OP_IdxIsNull, nColumn, cont);
      sqliteVdbeAddOp(v, OP_IdxRecno, pLevel->iCur, 0);
      if( i==pTabList->nSrc-1 && pushKey ){
        haveKey = 1;
      }else{
        sqliteVdbeAddOp(v, OP_MoveTo, iCur, 0);
        haveKey = 0;
      }
      pLevel->p1 = pLevel->iCur;
      pLevel->p2 = start;
    }else if( i<ARRAYSIZE(iDirectLt) && (iDirectLt[i]>=0 || iDirectGt[i]>=0) ){
      /* Case 3:  We have an inequality comparison against the ROWID field.
      */
      int testOp = OP_Noop;
      int start;

      brk = pLevel->brk = sqliteVdbeMakeLabel(v);
      cont = pLevel->cont = sqliteVdbeMakeLabel(v);
      if( iDirectGt[i]>=0 ){
        k = iDirectGt[i];
        assert( k<nExpr );
        assert( aExpr[k].p!=0 );
        assert( aExpr[k].idxLeft==iCur || aExpr[k].idxRight==iCur );
        if( aExpr[k].idxLeft==iCur ){
          sqliteExprCode(pParse, aExpr[k].p->pRight);
        }else{
          sqliteExprCode(pParse, aExpr[k].p->pLeft);
        }
        sqliteVdbeAddOp(v, OP_ForceInt,
          aExpr[k].p->op==TK_LT || aExpr[k].p->op==TK_GT, brk);
        sqliteVdbeAddOp(v, OP_MoveTo, iCur, brk);
        disableTerm(pLevel, &aExpr[k].p);
      }else{
        sqliteVdbeAddOp(v, OP_Rewind, iCur, brk);
      }
      if( iDirectLt[i]>=0 ){
        k = iDirectLt[i];
        assert( k<nExpr );
        assert( aExpr[k].p!=0 );
        assert( aExpr[k].idxLeft==iCur || aExpr[k].idxRight==iCur );
        if( aExpr[k].idxLeft==iCur ){
          sqliteExprCode(pParse, aExpr[k].p->pRight);
        }else{
          sqliteExprCode(pParse, aExpr[k].p->pLeft);
        }
        /* sqliteVdbeAddOp(v, OP_MustBeInt, 0, sqliteVdbeCurrentAddr(v)+1); */
        pLevel->iMem = pParse->nMem++;
        sqliteVdbeAddOp(v, OP_MemStore, pLevel->iMem, 1);
        if( aExpr[k].p->op==TK_LT || aExpr[k].p->op==TK_GT ){
          testOp = OP_Ge;
        }else{
          testOp = OP_Gt;
        }
        disableTerm(pLevel, &aExpr[k].p);
      }
      start = sqliteVdbeCurrentAddr(v);
      pLevel->op = OP_Next;
      pLevel->p1 = iCur;
      pLevel->p2 = start;
      if( testOp!=OP_Noop ){
        sqliteVdbeAddOp(v, OP_Recno, iCur, 0);
        sqliteVdbeAddOp(v, OP_MemLoad, pLevel->iMem, 0);
        sqliteVdbeAddOp(v, testOp, 0, brk);
      }
      haveKey = 0;
    }else if( pIdx==0 ){
      /* Case 4:  There is no usable index.  We must do a complete
      **          scan of the entire database table.
      */
      int start;

      brk = pLevel->brk = sqliteVdbeMakeLabel(v);
      cont = pLevel->cont = sqliteVdbeMakeLabel(v);
      sqliteVdbeAddOp(v, OP_Rewind, iCur, brk);
      start = sqliteVdbeCurrentAddr(v);
      pLevel->op = OP_Next;
      pLevel->p1 = iCur;
      pLevel->p2 = start;
      haveKey = 0;
    }else{
      /* Case 5: The WHERE clause term that refers to the right-most
      **         column of the index is an inequality.  For example, if
      **         the index is on (x,y,z) and the WHERE clause is of the
      **         form "x=5 AND y<10" then this case is used.  Only the
      **         right-most column can be an inequality - the rest must
      **         use the "==" operator.
      **
      **         This case is also used when there are no WHERE clause
      **         constraints but an index is selected anyway, in order
      **         to force the output order to conform to an ORDER BY.
      */
      int score = pLevel->score;
      int nEqColumn = score/8;
      int start;
      int leFlag, geFlag;
      int testOp;

      /* Evaluate the equality constraints
      */
      for(j=0; j<nEqColumn; j++){
        for(k=0; k<nExpr; k++){
          if( aExpr[k].p==0 ) continue;
          if( aExpr[k].idxLeft==iCur
             && aExpr[k].p->op==TK_EQ
             && (aExpr[k].prereqRight & loopMask)==aExpr[k].prereqRight 
             && aExpr[k].p->pLeft->iColumn==pIdx->aiColumn[j]
          ){
            sqliteExprCode(pParse, aExpr[k].p->pRight);
            disableTerm(pLevel, &aExpr[k].p);
            break;
          }
          if( aExpr[k].idxRight==iCur
             && aExpr[k].p->op==TK_EQ
             && (aExpr[k].prereqLeft & loopMask)==aExpr[k].prereqLeft
             && aExpr[k].p->pRight->iColumn==pIdx->aiColumn[j]
          ){
            sqliteExprCode(pParse, aExpr[k].p->pLeft);
            disableTerm(pLevel, &aExpr[k].p);
            break;
          }
        }
      }

      /* Duplicate the equality term values because they will all be
      ** used twice: once to make the termination key and once to make the
      ** start key.
      */
      for(j=0; j<nEqColumn; j++){
        sqliteVdbeAddOp(v, OP_Dup, nEqColumn-1, 0);
      }

      /* Labels for the beginning and end of the loop
      */
      cont = pLevel->cont = sqliteVdbeMakeLabel(v);
      brk = pLevel->brk = sqliteVdbeMakeLabel(v);

      /* Generate the termination key.  This is the key value that
      ** will end the search.  There is no termination key if there
      ** are no equality terms and no "X<..." term.
      **
      ** 2002-Dec-04: On a reverse-order scan, the so-called "termination"
      ** key computed here really ends up being the start key.
      */
      if( (score & 1)!=0 ){
        for(k=0; k<nExpr; k++){
          Expr *pExpr = aExpr[k].p;
          if( pExpr==0 ) continue;
          if( aExpr[k].idxLeft==iCur
             && (pExpr->op==TK_LT || pExpr->op==TK_LE)
             && (aExpr[k].prereqRight & loopMask)==aExpr[k].prereqRight 
             && pExpr->pLeft->iColumn==pIdx->aiColumn[j]
          ){
            sqliteExprCode(pParse, pExpr->pRight);
            leFlag = pExpr->op==TK_LE;
            disableTerm(pLevel, &aExpr[k].p);
            break;
          }
          if( aExpr[k].idxRight==iCur
             && (pExpr->op==TK_GT || pExpr->op==TK_GE)
             && (aExpr[k].prereqLeft & loopMask)==aExpr[k].prereqLeft
             && pExpr->pRight->iColumn==pIdx->aiColumn[j]
          ){
            sqliteExprCode(pParse, pExpr->pLeft);
            leFlag = pExpr->op==TK_GE;
            disableTerm(pLevel, &aExpr[k].p);
            break;
          }
        }
        testOp = OP_IdxGE;
      }else{
        testOp = nEqColumn>0 ? OP_IdxGE : OP_Noop;
        leFlag = 1;
      }
      if( testOp!=OP_Noop ){
        int nCol = nEqColumn + (score & 1);
        pLevel->iMem = pParse->nMem++;
        sqliteVdbeAddOp(v, OP_NotNull, -nCol, sqliteVdbeCurrentAddr(v)+3);
        sqliteVdbeAddOp(v, OP_Pop, nCol, 0);
        sqliteVdbeAddOp(v, OP_Goto, 0, brk);
        sqliteVdbeAddOp(v, OP_MakeKey, nCol, 0);
        sqliteAddIdxKeyType(v, pIdx);
        if( leFlag ){
          sqliteVdbeAddOp(v, OP_IncrKey, 0, 0);
        }
        if( pLevel->bRev ){
          sqliteVdbeAddOp(v, OP_MoveLt, pLevel->iCur, brk);
        }else{
          sqliteVdbeAddOp(v, OP_MemStore, pLevel->iMem, 1);
        }
      }else if( pLevel->bRev ){
        sqliteVdbeAddOp(v, OP_Last, pLevel->iCur, brk);
      }

      /* Generate the start key.  This is the key that defines the lower
      ** bound on the search.  There is no start key if there are no
      ** equality terms and if there is no "X>..." term.  In
      ** that case, generate a "Rewind" instruction in place of the
      ** start key search.
      **
      ** 2002-Dec-04: In the case of a reverse-order search, the so-called
      ** "start" key really ends up being used as the termination key.
      */
      if( (score & 2)!=0 ){
        for(k=0; k<nExpr; k++){
          Expr *pExpr = aExpr[k].p;
          if( pExpr==0 ) continue;
          if( aExpr[k].idxLeft==iCur
             && (pExpr->op==TK_GT || pExpr->op==TK_GE)
             && (aExpr[k].prereqRight & loopMask)==aExpr[k].prereqRight 
             && pExpr->pLeft->iColumn==pIdx->aiColumn[j]
          ){
            sqliteExprCode(pParse, pExpr->pRight);
            geFlag = pExpr->op==TK_GE;
            disableTerm(pLevel, &aExpr[k].p);
            break;
          }
          if( aExpr[k].idxRight==iCur
             && (pExpr->op==TK_LT || pExpr->op==TK_LE)
             && (aExpr[k].prereqLeft & loopMask)==aExpr[k].prereqLeft
             && pExpr->pRight->iColumn==pIdx->aiColumn[j]
          ){
            sqliteExprCode(pParse, pExpr->pLeft);
            geFlag = pExpr->op==TK_LE;
            disableTerm(pLevel, &aExpr[k].p);
            break;
          }
        }
      }else{
        geFlag = 1;
      }
      if( nEqColumn>0 || (score&2)!=0 ){
        int nCol = nEqColumn + ((score&2)!=0);
        sqliteVdbeAddOp(v, OP_NotNull, -nCol, sqliteVdbeCurrentAddr(v)+3);
        sqliteVdbeAddOp(v, OP_Pop, nCol, 0);
        sqliteVdbeAddOp(v, OP_Goto, 0, brk);
        sqliteVdbeAddOp(v, OP_MakeKey, nCol, 0);
        sqliteAddIdxKeyType(v, pIdx);
        if( !geFlag ){
          sqliteVdbeAddOp(v, OP_IncrKey, 0, 0);
        }
        if( pLevel->bRev ){
          pLevel->iMem = pParse->nMem++;
          sqliteVdbeAddOp(v, OP_MemStore, pLevel->iMem, 1);
          testOp = OP_IdxLT;
        }else{
          sqliteVdbeAddOp(v, OP_MoveTo, pLevel->iCur, brk);
        }
      }else if( pLevel->bRev ){
        testOp = OP_Noop;
      }else{
        sqliteVdbeAddOp(v, OP_Rewind, pLevel->iCur, brk);
      }

      /* Generate the the top of the loop.  If there is a termination
      ** key we have to test for that key and abort at the top of the
      ** loop.
      */
      start = sqliteVdbeCurrentAddr(v);
      if( testOp!=OP_Noop ){
        sqliteVdbeAddOp(v, OP_MemLoad, pLevel->iMem, 0);
        sqliteVdbeAddOp(v, testOp, pLevel->iCur, brk);
      }
      sqliteVdbeAddOp(v, OP_RowKey, pLevel->iCur, 0);
      sqliteVdbeAddOp(v, OP_IdxIsNull, nEqColumn + (score & 1), cont);
      sqliteVdbeAddOp(v, OP_IdxRecno, pLevel->iCur, 0);
      if( i==pTabList->nSrc-1 && pushKey ){
        haveKey = 1;
      }else{
        sqliteVdbeAddOp(v, OP_MoveTo, iCur, 0);
        haveKey = 0;
      }

      /* Record the instruction used to terminate the loop.
      */
      pLevel->op = pLevel->bRev ? OP_Prev : OP_Next;
      pLevel->p1 = pLevel->iCur;
      pLevel->p2 = start;
    }
    loopMask |= getMask(&maskSet, iCur);

    /* Insert code to test every subexpression that can be completely
    ** computed using the current set of tables.
    */
    for(j=0; j<nExpr; j++){
      if( aExpr[j].p==0 ) continue;
      if( (aExpr[j].prereqAll & loopMask)!=aExpr[j].prereqAll ) continue;
      if( pLevel->iLeftJoin && !ExprHasProperty(aExpr[j].p,EP_FromJoin) ){
        continue;
      }
      if( haveKey ){
        haveKey = 0;
        sqliteVdbeAddOp(v, OP_MoveTo, iCur, 0);
      }
      sqliteExprIfFalse(pParse, aExpr[j].p, cont, 1);
      aExpr[j].p = 0;
    }
    brk = cont;

    /* For a LEFT OUTER JOIN, generate code that will record the fact that
    ** at least one row of the right table has matched the left table.  
    */
    if( pLevel->iLeftJoin ){
      pLevel->top = sqliteVdbeCurrentAddr(v);
      sqliteVdbeAddOp(v, OP_Integer, 1, 0);
      sqliteVdbeAddOp(v, OP_MemStore, pLevel->iLeftJoin, 1);
      for(j=0; j<nExpr; j++){
        if( aExpr[j].p==0 ) continue;
        if( (aExpr[j].prereqAll & loopMask)!=aExpr[j].prereqAll ) continue;
        if( haveKey ){
          /* Cannot happen.  "haveKey" can only be true if pushKey is true
          ** an pushKey can only be true for DELETE and UPDATE and there are
          ** no outer joins with DELETE and UPDATE.
          */
          haveKey = 0;
          sqliteVdbeAddOp(v, OP_MoveTo, iCur, 0);
        }
        sqliteExprIfFalse(pParse, aExpr[j].p, cont, 1);
        aExpr[j].p = 0;
      }
    }
  }
  pWInfo->iContinue = cont;
  if( pushKey && !haveKey ){
    sqliteVdbeAddOp(v, OP_Recno, pTabList->a[0].iCursor, 0);
  }
  freeMaskSet(&maskSet);
  return pWInfo;
}
示例#6
0
static int sqliteCompileStmt(
  Parse *pParse,    /* parse context */
  Block *b,         /* current block */
  Stmt* pStmt,      /* statement to compile */
  int *tailgoto,    /* set *tailgoto to 1 if last statement is a goto */
  int in_excep      /* set to 1 when compiling an exception handler */
){
  Vdbe *v = sqliteGetVdbe(pParse);
  SrcList dummy;
  int i, j, skipgoto = 0;

  dummy.nSrc = 0;

  if( tailgoto ) *tailgoto = 0;

  if( pStmt->op!=TK_RAISE && pStmt->op!=TK_PROCEDURE && pStmt->pExpr1 ){
    Expr *pExpr = pStmt->pExpr1;
    if( pStmt->op==TK_FOR ) {
      /* allocate the FOR counter variable (see case TK_FOR below) */
      sqliteAddProcVar(pParse, &(pExpr->pLeft->token));
    }
    if( sqliteExprProcResolve(pParse, b, pExpr) ){
      return 1;
    }
    if( sqliteExprCheck(pParse, pExpr, 0, 0) ){
      return 1;
    }
  }

  switch( pStmt->op ) {

  case TK_ASSIGN:{
    Expr *pLeft = pStmt->pExpr1->pLeft;
    Expr *pRight = pStmt->pExpr1->pRight;

    assert( pStmt->pExpr1->op==TK_ASSIGN );
	  assert( pLeft->op==TK_VAR );
    sqliteExprCode(pParse, pRight);
	  if( pLeft->flags==EP_NotNull ){
      i = 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, i);
    }
    sqliteVdbeAddOp(v, OP_MemStore, pLeft->iColumn, 1);
	  break;
  }

  case TK_BLOCK:{
    if( sqliteCompileBlock(pParse, pStmt->pBlock) ){
      return 1;
    }
	  break;
  }

  case TK_CASE:{
    int jumpInst, addr;
    int nStmt;
    int searched;

    nStmt = pStmt->pStmt1->nStmt;
    searched = pStmt->pExpr1==0;
    assert( nStmt>0 );
    j = sqliteVdbeMakeLabel(v);
    if( !searched ){
      sqliteExprCode(pParse, pStmt->pExpr1);
    }
    for(i=0; i<nStmt; i++){
      Stmt *pWhen = pStmt->pStmt1->a[i].pStmt;
      assert( pWhen->op==TK_WHEN );
      if( sqliteExprProcResolve(pParse, b, pWhen->pExpr1) ){
        return 1;
      }
      if( sqliteExprCheck(pParse, pWhen->pExpr1, 0, 0) ){
        return 1;
      }
      sqliteExprCode(pParse, pWhen->pExpr1);
      if( !searched ){
        sqliteVdbeAddOp(v, OP_Dup, 1, 1);
        jumpInst = sqliteVdbeAddOp(v, OP_Ne, 1, 0);
      }else{
        jumpInst = sqliteVdbeAddOp(v, OP_IfNot, 1, 0);
      }
	    if( sqliteCompileList(pParse, b, pWhen->pStmt1, &skipgoto, 0) ){
	      return 1;
      }
      if( !skipgoto ) {
        sqliteVdbeAddOp(v, OP_Goto, 0, j);
      }
      addr = sqliteVdbeCurrentAddr(v);
      sqliteVdbeChangeP2(v, jumpInst, addr);
    }
    if( !searched ){
      sqliteVdbeAddOp(v, OP_Pop, 1, 0);
    }
    if( pStmt->pStmt2 ){
      assert( pStmt->pStmt2->op==TK_ELSE );
	    if( sqliteCompileList(pParse, b, pStmt->pStmt2->pStmt1, tailgoto, 0) ){
	      return 1;
      }
    }else{
      sqliteVdbeOp3(v, OP_Raise, 0, 0, "CASE_NOT_FOUND", P3_STATIC);
      if( tailgoto ) *tailgoto = 1;
    }
    sqliteVdbeResolveLabel(v, j);
    break;
  }

  case TK_EXIT:{
    if( pParse->iLoopExit==0 ) {
      sqliteErrorMsg(pParse, "EXIT used outside loop statement", 0);
      return 1;
    }
    if( pStmt->pExpr1 ) {
      sqliteExprCode(pParse, pStmt->pExpr1);
      sqliteVdbeAddOp(v, OP_If, 1, pParse->iLoopExit);
    } else {
      sqliteVdbeAddOp(v, OP_Goto, 0, pParse->iLoopExit);
      if( tailgoto ) *tailgoto = 1;
    }
	  break;
  }

  case TK_FOR:{
    Expr *pLow = pStmt->pExpr1->pRight->pLeft;
    Expr *pHigh = pStmt->pExpr1->pRight->pRight;
    int iCounter, iHigh, iPrevExit;

	  assert( pStmt->pExpr1->op==TK_ASSIGN );
	  assert( pStmt->pExpr1->pLeft->op==TK_VAR );
	  assert( pStmt->pExpr1->pRight->op==TK_FOR );
    iCounter = pParse->nMem-1;
    iHigh = pParse->nMem++;
    sqliteExprCode(pParse, pLow);
    sqliteVdbeAddOp(v, OP_MemStore, iCounter, 1);
    sqliteExprCode(pParse, pHigh);
    sqliteVdbeAddOp(v, OP_MemStore, iHigh, 1);
    sqliteVdbeAddOp(v, OP_MemLoad, iCounter, 0);
    i = sqliteVdbeCurrentAddr(v);
    sqliteVdbeAddOp(v, OP_MemLoad, iHigh, 0);
    iPrevExit = pParse->iLoopExit;
    pParse->iLoopExit = sqliteVdbeMakeLabel(v);
    sqliteVdbeAddOp(v, OP_Gt, 1, pParse->iLoopExit);
	  if( sqliteCompileList(pParse, b, pStmt->pStmt1, 0, 0) ){
	    return 1;
    }
    sqliteVdbeAddOp(v, OP_MemLoad, iCounter, 0);
    sqliteVdbeAddOp(v, OP_Integer, 1, 0);
    sqliteVdbeAddOp(v, OP_Add, 0, 0);
    sqliteVdbeAddOp(v, OP_MemStore, iCounter, 0);
    sqliteVdbeAddOp(v, OP_Goto, 0, i);
    sqliteVdbeResolveLabel(v, pParse->iLoopExit);
    pParse->iLoopExit = iPrevExit;
    hideVar(b, iCounter);
    break;
  }

  case TK_IF: {
    i = sqliteVdbeMakeLabel(v);
    j = sqliteVdbeMakeLabel(v);
    sqliteExprCode(pParse, pStmt->pExpr1);
    sqliteVdbeAddOp(v, OP_IfNot, 1, j);
	  if( sqliteCompileList(pParse, b, pStmt->pStmt1, &skipgoto, 0) ){
	    return 1;
    }
    while( pStmt->pStmt2 ) {
      if( !skipgoto ) {
        sqliteVdbeAddOp(v, OP_Goto, 0, i);
      }
      sqliteVdbeResolveLabel(v, j);
      j = sqliteVdbeMakeLabel(v);
      pStmt = pStmt->pStmt2;
      assert( pStmt->op==TK_ELSE || pStmt->op==TK_ELSIF );
      if( pStmt->op==TK_ELSIF ) {
        if( sqliteExprProcResolve(pParse, b, pStmt->pExpr1) ){
          return 1;
        }
        if( sqliteExprCheck(pParse, pStmt->pExpr1, 0, 0) ){
          return 1;
        }
        sqliteExprCode(pParse, pStmt->pExpr1);
        sqliteVdbeAddOp(v, OP_IfNot, 1, j);
      }
	    if( sqliteCompileList(pParse, b, pStmt->pStmt1, &skipgoto, 0) ){
	      return 1;
      }
    }
    sqliteVdbeResolveLabel(v, i);
    sqliteVdbeResolveLabel(v, j);
	  break;
  }

  case TK_LOOP:{
    int iPrevExit = pParse->iLoopExit;
    pParse->iLoopExit = sqliteVdbeMakeLabel(v);
    i = sqliteVdbeCurrentAddr(v);
	  if( sqliteCompileList(pParse, b, pStmt->pStmt1, 0, 0) ){
	    return 1;
    }
    sqliteVdbeAddOp(v, OP_Goto, 0, i);
    sqliteVdbeResolveLabel(v, pParse->iLoopExit);
    pParse->iLoopExit = iPrevExit;
	  break;
  }

  case TK_NULL:{
	  break;
  }

  case TK_PRINT:{
    sqliteExprCode(pParse, pStmt->pExpr1);
    sqliteVdbeAddOp(v, OP_Print, 0, 0);
	  break;
  }

  case TK_PROCEDURE: {
    Expr *pExpr = pStmt->pExpr1;
    if( sqliteCompileCall(pParse, &(pExpr->token), pExpr->pList) ) {
      return 1;
    }
    sqliteVdbeAddOp(v, OP_Pop, 1, 0);
	  break;
  }

  case TK_RAISE:{
    if( pStmt->pExpr1==0 ) {
      if( !in_excep ) {
        sqliteErrorMsg(pParse, "RAISE without argument illegal outside exception handler", 0);
        return 1;
      }
      sqliteVdbeOp3(v, OP_Raise, 0, 0, 0, P3_STATIC);
    } else {
      char *zName = 0;
      sqliteSetNString(&zName, pStmt->pExpr1->token.z, pStmt->pExpr1->token.n, 0);
      sqliteVdbeOp3(v, OP_Raise, 0, 0, zName, P3_DYNAMIC);
    }
    if( tailgoto ) *tailgoto = 1;
	  break;
  }

  case TK_RETURN:{
    sqliteExprCode(pParse, pStmt->pExpr1);
    sqliteVdbeAddOp(v, OP_MemStore, b->mReturn, 1);
    sqliteVdbeAddOp(v, OP_Goto, 0, b->nExit);
    if( tailgoto ) *tailgoto = 1;
	  break;
  }

  case TK_SQL:{
	  sqliteCompileSQLStmt(pParse, b, pStmt->pSql);
	  break;
  }

  case TK_WHILE:{
    int iPrevExit = pParse->iLoopExit;
    pParse->iLoopExit = sqliteVdbeMakeLabel(v);
    i = sqliteVdbeCurrentAddr(v);
    sqliteExprCode(pParse, pStmt->pExpr1);
    sqliteVdbeAddOp(v, OP_IfNot, 1, pParse->iLoopExit);
	  if( sqliteCompileList(pParse, b, pStmt->pStmt1, 0, 0) ){
	    return 1;
    }
    sqliteVdbeAddOp(v, OP_Goto, 0, i);
    sqliteVdbeResolveLabel(v, pParse->iLoopExit);
    pParse->iLoopExit = iPrevExit;
	  break;
  }

  }
  return 0;
}
示例#7
0
文件: insert.c 项目: andreiw/polaris
/*
** 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);
}
示例#8
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;
}
示例#9
0
/*
** Generate code for a boolean expression such that a jump is made
** to the label "dest" if the expression is false but execution
** continues straight thru if the expression is true.
**
** If the expression evaluates to NULL (neither true nor false) then
** jump if jumpIfNull is true or fall through if jumpIfNull is false.
*/
void sqliteExprIfFalse(Parse *pParse, Expr *pExpr, int dest, int jumpIfNull){
  Vdbe *v = pParse->pVdbe;
  int op = 0;
  if( v==0 || pExpr==0 ) return;
  switch( pExpr->op ){
    case TK_LT:       op = OP_Ge;       break;
    case TK_LE:       op = OP_Gt;       break;
    case TK_GT:       op = OP_Le;       break;
    case TK_GE:       op = OP_Lt;       break;
    case TK_NE:       op = OP_Eq;       break;
    case TK_EQ:       op = OP_Ne;       break;
    case TK_ISNULL:   op = OP_NotNull;  break;
    case TK_NOTNULL:  op = OP_IsNull;   break;
    default:  break;
  }
  switch( pExpr->op ){
    case TK_AND: {
      sqliteExprIfFalse(pParse, pExpr->pLeft, dest, jumpIfNull);
      sqliteExprIfFalse(pParse, pExpr->pRight, dest, jumpIfNull);
      break;
    }
    case TK_OR: {
      int d2 = sqliteVdbeMakeLabel(v);
      sqliteExprIfTrue(pParse, pExpr->pLeft, d2, !jumpIfNull);
      sqliteExprIfFalse(pParse, pExpr->pRight, dest, jumpIfNull);
      sqliteVdbeResolveLabel(v, d2);
      break;
    }
    case TK_NOT: {
      sqliteExprIfTrue(pParse, pExpr->pLeft, dest, jumpIfNull);
      break;
    }
    case TK_LT:
    case TK_LE:
    case TK_GT:
    case TK_GE:
    case TK_NE:
    case TK_EQ: {
      if( pParse->db->file_format>=4 && sqliteExprType(pExpr)==SQLITE_SO_TEXT ){
        /* Convert numeric comparison opcodes into text comparison opcodes.
        ** This step depends on the fact that the text comparision opcodes are
        ** always 6 greater than their corresponding numeric comparison
        ** opcodes.
        */
        assert( OP_Eq+6 == OP_StrEq );
        op += 6;
      }
      sqliteExprCode(pParse, pExpr->pLeft);
      sqliteExprCode(pParse, pExpr->pRight);
      sqliteVdbeAddOp(v, op, jumpIfNull, dest);
      break;
    }
    case TK_ISNULL:
    case TK_NOTNULL: {
      sqliteExprCode(pParse, pExpr->pLeft);
      sqliteVdbeAddOp(v, op, 1, dest);
      break;
    }
    case TK_IN: {
      int addr;
      sqliteExprCode(pParse, pExpr->pLeft);
      addr = sqliteVdbeCurrentAddr(v);
      sqliteVdbeAddOp(v, OP_NotNull, -1, addr+3);
      sqliteVdbeAddOp(v, OP_Pop, 1, 0);
      sqliteVdbeAddOp(v, OP_Goto, 0, jumpIfNull ? dest : addr+4);
      if( pExpr->pSelect ){
        sqliteVdbeAddOp(v, OP_NotFound, pExpr->iTable, dest);
      }else{
        sqliteVdbeAddOp(v, OP_SetNotFound, pExpr->iTable, dest);
      }
      break;
    }
    case TK_BETWEEN: {
      int addr;
      sqliteExprCode(pParse, pExpr->pLeft);
      sqliteVdbeAddOp(v, OP_Dup, 0, 0);
      sqliteExprCode(pParse, pExpr->pList->a[0].pExpr);
      addr = sqliteVdbeCurrentAddr(v);
      sqliteVdbeAddOp(v, OP_Ge, !jumpIfNull, addr+3);
      sqliteVdbeAddOp(v, OP_Pop, 1, 0);
      sqliteVdbeAddOp(v, OP_Goto, 0, dest);
      sqliteExprCode(pParse, pExpr->pList->a[1].pExpr);
      sqliteVdbeAddOp(v, OP_Gt, jumpIfNull, dest);
      break;
    }
    default: {
      sqliteExprCode(pParse, pExpr);
      sqliteVdbeAddOp(v, OP_IfNot, jumpIfNull, dest);
      break;
    }
  }
}
示例#10
0
/*
** Generate code for a boolean expression such that a jump is made
** to the label "dest" if the expression is true but execution
** continues straight thru if the expression is false.
**
** If the expression evaluates to NULL (neither true nor false), then
** take the jump if the jumpIfNull flag is true.
*/
void sqliteExprIfTrue(Parse *pParse, Expr *pExpr, int dest, int jumpIfNull){
  Vdbe *v = pParse->pVdbe;
  int op = 0;
  if( v==0 || pExpr==0 ) return;
  switch( pExpr->op ){
    case TK_LT:       op = OP_Lt;       break;
    case TK_LE:       op = OP_Le;       break;
    case TK_GT:       op = OP_Gt;       break;
    case TK_GE:       op = OP_Ge;       break;
    case TK_NE:       op = OP_Ne;       break;
    case TK_EQ:       op = OP_Eq;       break;
    case TK_ISNULL:   op = OP_IsNull;   break;
    case TK_NOTNULL:  op = OP_NotNull;  break;
    default:  break;
  }
  switch( pExpr->op ){
    case TK_AND: {
      int d2 = sqliteVdbeMakeLabel(v);
      sqliteExprIfFalse(pParse, pExpr->pLeft, d2, !jumpIfNull);
      sqliteExprIfTrue(pParse, pExpr->pRight, dest, jumpIfNull);
      sqliteVdbeResolveLabel(v, d2);
      break;
    }
    case TK_OR: {
      sqliteExprIfTrue(pParse, pExpr->pLeft, dest, jumpIfNull);
      sqliteExprIfTrue(pParse, pExpr->pRight, dest, jumpIfNull);
      break;
    }
    case TK_NOT: {
      sqliteExprIfFalse(pParse, pExpr->pLeft, dest, jumpIfNull);
      break;
    }
    case TK_LT:
    case TK_LE:
    case TK_GT:
    case TK_GE:
    case TK_NE:
    case TK_EQ: {
      sqliteExprCode(pParse, pExpr->pLeft);
      sqliteExprCode(pParse, pExpr->pRight);
      if( pParse->db->file_format>=4 && sqliteExprType(pExpr)==SQLITE_SO_TEXT ){
        op += 6;  /* Convert numeric opcodes to text opcodes */
      }
      sqliteVdbeAddOp(v, op, jumpIfNull, dest);
      break;
    }
    case TK_ISNULL:
    case TK_NOTNULL: {
      sqliteExprCode(pParse, pExpr->pLeft);
      sqliteVdbeAddOp(v, op, 1, dest);
      break;
    }
    case TK_IN: {
      int addr;
      sqliteExprCode(pParse, pExpr->pLeft);
      addr = sqliteVdbeCurrentAddr(v);
      sqliteVdbeAddOp(v, OP_NotNull, -1, addr+3);
      sqliteVdbeAddOp(v, OP_Pop, 1, 0);
      sqliteVdbeAddOp(v, OP_Goto, 0, jumpIfNull ? dest : addr+4);
      if( pExpr->pSelect ){
        sqliteVdbeAddOp(v, OP_Found, pExpr->iTable, dest);
      }else{
        sqliteVdbeAddOp(v, OP_SetFound, pExpr->iTable, dest);
      }
      break;
    }
    case TK_BETWEEN: {
      int addr;
      sqliteExprCode(pParse, pExpr->pLeft);
      sqliteVdbeAddOp(v, OP_Dup, 0, 0);
      sqliteExprCode(pParse, pExpr->pList->a[0].pExpr);
      addr = sqliteVdbeAddOp(v, OP_Lt, !jumpIfNull, 0);
      sqliteExprCode(pParse, pExpr->pList->a[1].pExpr);
      sqliteVdbeAddOp(v, OP_Le, jumpIfNull, dest);
      sqliteVdbeAddOp(v, OP_Integer, 0, 0);
      sqliteVdbeChangeP2(v, addr, sqliteVdbeCurrentAddr(v));
      sqliteVdbeAddOp(v, OP_Pop, 1, 0);
      break;
    }
    default: {
      sqliteExprCode(pParse, pExpr);
      sqliteVdbeAddOp(v, OP_If, jumpIfNull, dest);
      break;
    }
  }
}
示例#11
0
/*
** Generate code into the current Vdbe to evaluate the given
** expression and leave the result on the top of stack.
*/
void sqliteExprCode(Parse *pParse, Expr *pExpr){
  Vdbe *v = pParse->pVdbe;
  int op;
  if( v==0 || pExpr==0 ) return;
  switch( pExpr->op ){
    case TK_PLUS:     op = OP_Add;      break;
    case TK_MINUS:    op = OP_Subtract; break;
    case TK_STAR:     op = OP_Multiply; break;
    case TK_SLASH:    op = OP_Divide;   break;
    case TK_AND:      op = OP_And;      break;
    case TK_OR:       op = OP_Or;       break;
    case TK_LT:       op = OP_Lt;       break;
    case TK_LE:       op = OP_Le;       break;
    case TK_GT:       op = OP_Gt;       break;
    case TK_GE:       op = OP_Ge;       break;
    case TK_NE:       op = OP_Ne;       break;
    case TK_EQ:       op = OP_Eq;       break;
    case TK_ISNULL:   op = OP_IsNull;   break;
    case TK_NOTNULL:  op = OP_NotNull;  break;
    case TK_NOT:      op = OP_Not;      break;
    case TK_UMINUS:   op = OP_Negative; break;
    case TK_BITAND:   op = OP_BitAnd;   break;
    case TK_BITOR:    op = OP_BitOr;    break;
    case TK_BITNOT:   op = OP_BitNot;   break;
    case TK_LSHIFT:   op = OP_ShiftLeft;  break;
    case TK_RSHIFT:   op = OP_ShiftRight; break;
    case TK_REM:      op = OP_Remainder;  break;
    default: break;
  }
  switch( pExpr->op ){
    case TK_COLUMN: {
      if( pParse->useAgg ){
        sqliteVdbeAddOp(v, OP_AggGet, 0, pExpr->iAgg);
      }else if( pExpr->iColumn>=0 ){
        sqliteVdbeAddOp(v, OP_Column, pExpr->iTable, pExpr->iColumn);
      }else{
        sqliteVdbeAddOp(v, OP_Recno, pExpr->iTable, 0);
      }
      break;
    }
    case TK_STRING:
    case TK_FLOAT:
    case TK_INTEGER: {
      if( pExpr->op==TK_INTEGER && sqliteFitsIn32Bits(pExpr->token.z) ){
        sqliteVdbeAddOp(v, OP_Integer, atoi(pExpr->token.z), 0);
      }else{
        sqliteVdbeAddOp(v, OP_String, 0, 0);
      }
      assert( pExpr->token.z );
      sqliteVdbeChangeP3(v, -1, pExpr->token.z, pExpr->token.n);
      sqliteVdbeDequoteP3(v, -1);
      break;
    }
    case TK_NULL: {
      sqliteVdbeAddOp(v, OP_String, 0, 0);
      break;
    }
    case TK_VARIABLE: {
      sqliteVdbeAddOp(v, OP_Variable, pExpr->iTable, 0);
      break;
    }
    case TK_LT:
    case TK_LE:
    case TK_GT:
    case TK_GE:
    case TK_NE:
    case TK_EQ: {
      if( pParse->db->file_format>=4 && sqliteExprType(pExpr)==SQLITE_SO_TEXT ){
        op += 6;  /* Convert numeric opcodes to text opcodes */
      }
      /* Fall through into the next case */
    }
    case TK_AND:
    case TK_OR:
    case TK_PLUS:
    case TK_STAR:
    case TK_MINUS:
    case TK_REM:
    case TK_BITAND:
    case TK_BITOR:
    case TK_SLASH: {
      sqliteExprCode(pParse, pExpr->pLeft);
      sqliteExprCode(pParse, pExpr->pRight);
      sqliteVdbeAddOp(v, op, 0, 0);
      break;
    }
    case TK_LSHIFT:
    case TK_RSHIFT: {
      sqliteExprCode(pParse, pExpr->pRight);
      sqliteExprCode(pParse, pExpr->pLeft);
      sqliteVdbeAddOp(v, op, 0, 0);
      break;
    }
    case TK_CONCAT: {
      sqliteExprCode(pParse, pExpr->pLeft);
      sqliteExprCode(pParse, pExpr->pRight);
      sqliteVdbeAddOp(v, OP_Concat, 2, 0);
      break;
    }
    case TK_UMINUS: {
      assert( pExpr->pLeft );
      if( pExpr->pLeft->op==TK_FLOAT || pExpr->pLeft->op==TK_INTEGER ){
        Token *p = &pExpr->pLeft->token;
        char *z = sqliteMalloc( p->n + 2 );
        sprintf(z, "-%.*s", p->n, p->z);
        if( pExpr->pLeft->op==TK_INTEGER && sqliteFitsIn32Bits(z) ){
          sqliteVdbeAddOp(v, OP_Integer, atoi(z), 0);
        }else{
          sqliteVdbeAddOp(v, OP_String, 0, 0);
        }
        sqliteVdbeChangeP3(v, -1, z, p->n+1);
        sqliteFree(z);
        break;
      }
      /* Fall through into TK_NOT */
    }
    case TK_BITNOT:
    case TK_NOT: {
      sqliteExprCode(pParse, pExpr->pLeft);
      sqliteVdbeAddOp(v, op, 0, 0);
      break;
    }
    case TK_ISNULL:
    case TK_NOTNULL: {
      int dest;
      sqliteVdbeAddOp(v, OP_Integer, 1, 0);
      sqliteExprCode(pParse, pExpr->pLeft);
      dest = sqliteVdbeCurrentAddr(v) + 2;
      sqliteVdbeAddOp(v, op, 1, dest);
      sqliteVdbeAddOp(v, OP_AddImm, -1, 0);
      break;
    }
    case TK_AGG_FUNCTION: {
      sqliteVdbeAddOp(v, OP_AggGet, 0, pExpr->iAgg);
      break;
    }
    case TK_GLOB:
    case TK_LIKE:
    case TK_FUNCTION: {
      ExprList *pList = pExpr->pList;
      int nExpr = pList ? pList->nExpr : 0;
      FuncDef *pDef;
      int nId;
      const char *zId;
      getFunctionName(pExpr, &zId, &nId);
      pDef = sqliteFindFunction(pParse->db, zId, nId, nExpr, 0);
      assert( pDef!=0 );
      nExpr = sqliteExprCodeExprList(pParse, pList, pDef->includeTypes);
      sqliteVdbeOp3(v, OP_Function, nExpr, 0, (char*)pDef, P3_POINTER);
      break;
    }
    case TK_SELECT: {
      sqliteVdbeAddOp(v, OP_MemLoad, pExpr->iColumn, 0);
      break;
    }
    case TK_IN: {
      int addr;
      sqliteVdbeAddOp(v, OP_Integer, 1, 0);
      sqliteExprCode(pParse, pExpr->pLeft);
      addr = sqliteVdbeCurrentAddr(v);
      sqliteVdbeAddOp(v, OP_NotNull, -1, addr+4);
      sqliteVdbeAddOp(v, OP_Pop, 1, 0);
      sqliteVdbeAddOp(v, OP_String, 0, 0);
      sqliteVdbeAddOp(v, OP_Goto, 0, addr+6);
      if( pExpr->pSelect ){
        sqliteVdbeAddOp(v, OP_Found, pExpr->iTable, addr+6);
      }else{
        sqliteVdbeAddOp(v, OP_SetFound, pExpr->iTable, addr+6);
      }
      sqliteVdbeAddOp(v, OP_AddImm, -1, 0);
      break;
    }
    case TK_BETWEEN: {
      sqliteExprCode(pParse, pExpr->pLeft);
      sqliteVdbeAddOp(v, OP_Dup, 0, 0);
      sqliteExprCode(pParse, pExpr->pList->a[0].pExpr);
      sqliteVdbeAddOp(v, OP_Ge, 0, 0);
      sqliteVdbeAddOp(v, OP_Pull, 1, 0);
      sqliteExprCode(pParse, pExpr->pList->a[1].pExpr);
      sqliteVdbeAddOp(v, OP_Le, 0, 0);
      sqliteVdbeAddOp(v, OP_And, 0, 0);
      break;
    }
    case TK_UPLUS:
    case TK_AS: {
      sqliteExprCode(pParse, pExpr->pLeft);
      break;
    }
    case TK_CASE: {
      int expr_end_label;
      int jumpInst;
      int addr;
      int nExpr;
      int i;

      assert(pExpr->pList);
      assert((pExpr->pList->nExpr % 2) == 0);
      assert(pExpr->pList->nExpr > 0);
      nExpr = pExpr->pList->nExpr;
      expr_end_label = sqliteVdbeMakeLabel(v);
      if( pExpr->pLeft ){
        sqliteExprCode(pParse, pExpr->pLeft);
      }
      for(i=0; i<nExpr; i=i+2){
        sqliteExprCode(pParse, pExpr->pList->a[i].pExpr);
        if( pExpr->pLeft ){
          sqliteVdbeAddOp(v, OP_Dup, 1, 1);
          jumpInst = sqliteVdbeAddOp(v, OP_Ne, 1, 0);
          sqliteVdbeAddOp(v, OP_Pop, 1, 0);
        }else{
          jumpInst = sqliteVdbeAddOp(v, OP_IfNot, 1, 0);
        }
        sqliteExprCode(pParse, pExpr->pList->a[i+1].pExpr);
        sqliteVdbeAddOp(v, OP_Goto, 0, expr_end_label);
        addr = sqliteVdbeCurrentAddr(v);
        sqliteVdbeChangeP2(v, jumpInst, addr);
      }
      if( pExpr->pLeft ){
        sqliteVdbeAddOp(v, OP_Pop, 1, 0);
      }
      if( pExpr->pRight ){
        sqliteExprCode(pParse, pExpr->pRight);
      }else{
        sqliteVdbeAddOp(v, OP_String, 0, 0);
      }
      sqliteVdbeResolveLabel(v, expr_end_label);
      break;
    }
    case TK_RAISE: {
      if( !pParse->trigStack ){
        sqliteErrorMsg(pParse,
                       "RAISE() may only be used within a trigger-program");
        pParse->nErr++;
	return;
      }
      if( pExpr->iColumn == OE_Rollback ||
	  pExpr->iColumn == OE_Abort ||
	  pExpr->iColumn == OE_Fail ){
	  sqliteVdbeOp3(v, OP_Halt, SQLITE_CONSTRAINT, pExpr->iColumn,
                           pExpr->token.z, pExpr->token.n);
	  sqliteVdbeDequoteP3(v, -1);
      } else {
	  assert( pExpr->iColumn == OE_Ignore );
	  sqliteVdbeOp3(v, OP_Goto, 0, pParse->trigStack->ignoreJump,
                           "(IGNORE jump)", 0);
      }
    }
    break;
  }
}