4309 lines
		
	
	
		
			146 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			4309 lines
		
	
	
		
			146 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
 | |
| ** 2001 September 15
 | |
| **
 | |
| ** The author disclaims copyright to this source code.  In place of
 | |
| ** a legal notice, here is a blessing:
 | |
| **
 | |
| **    May you do good and not evil.
 | |
| **    May you find forgiveness for yourself and forgive others.
 | |
| **    May you share freely, never taking more than you give.
 | |
| **
 | |
| *************************************************************************
 | |
| ** This file contains routines used for analyzing expressions and
 | |
| ** for generating VDBE code that evaluates expressions in SQLite.
 | |
| */
 | |
| #include "sqliteInt.h"
 | |
| 
 | |
| /*
 | |
| ** Return the 'affinity' of the expression pExpr if any.
 | |
| **
 | |
| ** If pExpr is a column, a reference to a column via an 'AS' alias,
 | |
| ** or a sub-select with a column as the return value, then the 
 | |
| ** affinity of that column is returned. Otherwise, 0x00 is returned,
 | |
| ** indicating no affinity for the expression.
 | |
| **
 | |
| ** i.e. the WHERE clause expressions in the following statements all
 | |
| ** have an affinity:
 | |
| **
 | |
| ** CREATE TABLE t1(a);
 | |
| ** SELECT * FROM t1 WHERE a;
 | |
| ** SELECT a AS b FROM t1 WHERE b;
 | |
| ** SELECT * FROM t1 WHERE (select a from t1);
 | |
| */
 | |
| char sqlite3ExprAffinity(Expr *pExpr){
 | |
|   int op;
 | |
|   pExpr = sqlite3ExprSkipCollate(pExpr);
 | |
|   if( pExpr->flags & EP_Generic ) return 0;
 | |
|   op = pExpr->op;
 | |
|   if( op==TK_SELECT ){
 | |
|     assert( pExpr->flags&EP_xIsSelect );
 | |
|     return sqlite3ExprAffinity(pExpr->x.pSelect->pEList->a[0].pExpr);
 | |
|   }
 | |
| #ifndef SQLITE_OMIT_CAST
 | |
|   if( op==TK_CAST ){
 | |
|     assert( !ExprHasProperty(pExpr, EP_IntValue) );
 | |
|     return sqlite3AffinityType(pExpr->u.zToken, 0);
 | |
|   }
 | |
| #endif
 | |
|   if( (op==TK_AGG_COLUMN || op==TK_COLUMN || op==TK_REGISTER) 
 | |
|    && pExpr->pTab!=0
 | |
|   ){
 | |
|     /* op==TK_REGISTER && pExpr->pTab!=0 happens when pExpr was originally
 | |
|     ** a TK_COLUMN but was previously evaluated and cached in a register */
 | |
|     int j = pExpr->iColumn;
 | |
|     if( j<0 ) return SQLITE_AFF_INTEGER;
 | |
|     assert( pExpr->pTab && j<pExpr->pTab->nCol );
 | |
|     return pExpr->pTab->aCol[j].affinity;
 | |
|   }
 | |
|   return pExpr->affinity;
 | |
| }
 | |
| 
 | |
| /*
 | |
| ** Set the collating sequence for expression pExpr to be the collating
 | |
| ** sequence named by pToken.   Return a pointer to a new Expr node that
 | |
| ** implements the COLLATE operator.
 | |
| **
 | |
| ** If a memory allocation error occurs, that fact is recorded in pParse->db
 | |
| ** and the pExpr parameter is returned unchanged.
 | |
| */
 | |
| Expr *sqlite3ExprAddCollateToken(
 | |
|   Parse *pParse,           /* Parsing context */
 | |
|   Expr *pExpr,             /* Add the "COLLATE" clause to this expression */
 | |
|   const Token *pCollName,  /* Name of collating sequence */
 | |
|   int dequote              /* True to dequote pCollName */
 | |
| ){
 | |
|   if( pCollName->n>0 ){
 | |
|     Expr *pNew = sqlite3ExprAlloc(pParse->db, TK_COLLATE, pCollName, dequote);
 | |
|     if( pNew ){
 | |
|       pNew->pLeft = pExpr;
 | |
|       pNew->flags |= EP_Collate|EP_Skip;
 | |
|       pExpr = pNew;
 | |
|     }
 | |
|   }
 | |
|   return pExpr;
 | |
| }
 | |
| Expr *sqlite3ExprAddCollateString(Parse *pParse, Expr *pExpr, const char *zC){
 | |
|   Token s;
 | |
|   assert( zC!=0 );
 | |
|   sqlite3TokenInit(&s, (char*)zC);
 | |
|   return sqlite3ExprAddCollateToken(pParse, pExpr, &s, 0);
 | |
| }
 | |
| 
 | |
| /*
 | |
| ** Skip over any TK_COLLATE operators and any unlikely()
 | |
| ** or likelihood() function at the root of an expression.
 | |
| */
 | |
| Expr *sqlite3ExprSkipCollate(Expr *pExpr){
 | |
|   while( pExpr && ExprHasProperty(pExpr, EP_Skip) ){
 | |
|     if( ExprHasProperty(pExpr, EP_Unlikely) ){
 | |
|       assert( !ExprHasProperty(pExpr, EP_xIsSelect) );
 | |
|       assert( pExpr->x.pList->nExpr>0 );
 | |
|       assert( pExpr->op==TK_FUNCTION );
 | |
|       pExpr = pExpr->x.pList->a[0].pExpr;
 | |
|     }else{
 | |
|       assert( pExpr->op==TK_COLLATE );
 | |
|       pExpr = pExpr->pLeft;
 | |
|     }
 | |
|   }   
 | |
|   return pExpr;
 | |
| }
 | |
| 
 | |
| /*
 | |
| ** Return the collation sequence for the expression pExpr. If
 | |
| ** there is no defined collating sequence, return NULL.
 | |
| **
 | |
| ** The collating sequence might be determined by a COLLATE operator
 | |
| ** or by the presence of a column with a defined collating sequence.
 | |
| ** COLLATE operators take first precedence.  Left operands take
 | |
| ** precedence over right operands.
 | |
| */
 | |
| CollSeq *sqlite3ExprCollSeq(Parse *pParse, Expr *pExpr){
 | |
|   sqlite3 *db = pParse->db;
 | |
|   CollSeq *pColl = 0;
 | |
|   Expr *p = pExpr;
 | |
|   while( p ){
 | |
|     int op = p->op;
 | |
|     if( p->flags & EP_Generic ) break;
 | |
|     if( op==TK_CAST || op==TK_UPLUS ){
 | |
|       p = p->pLeft;
 | |
|       continue;
 | |
|     }
 | |
|     if( op==TK_COLLATE || (op==TK_REGISTER && p->op2==TK_COLLATE) ){
 | |
|       pColl = sqlite3GetCollSeq(pParse, ENC(db), 0, p->u.zToken);
 | |
|       break;
 | |
|     }
 | |
|     if( (op==TK_AGG_COLUMN || op==TK_COLUMN
 | |
|           || op==TK_REGISTER || op==TK_TRIGGER)
 | |
|      && p->pTab!=0
 | |
|     ){
 | |
|       /* op==TK_REGISTER && p->pTab!=0 happens when pExpr was originally
 | |
|       ** a TK_COLUMN but was previously evaluated and cached in a register */
 | |
|       int j = p->iColumn;
 | |
|       if( j>=0 ){
 | |
|         const char *zColl = p->pTab->aCol[j].zColl;
 | |
|         pColl = sqlite3FindCollSeq(db, ENC(db), zColl, 0);
 | |
|       }
 | |
|       break;
 | |
|     }
 | |
|     if( p->flags & EP_Collate ){
 | |
|       if( p->pLeft && (p->pLeft->flags & EP_Collate)!=0 ){
 | |
|         p = p->pLeft;
 | |
|       }else{
 | |
|         Expr *pNext  = p->pRight;
 | |
|         /* The Expr.x union is never used at the same time as Expr.pRight */
 | |
|         assert( p->x.pList==0 || p->pRight==0 );
 | |
|         /* p->flags holds EP_Collate and p->pLeft->flags does not.  And
 | |
|         ** p->x.pSelect cannot.  So if p->x.pLeft exists, it must hold at
 | |
|         ** least one EP_Collate. Thus the following two ALWAYS. */
 | |
|         if( p->x.pList!=0 && ALWAYS(!ExprHasProperty(p, EP_xIsSelect)) ){
 | |
|           int i;
 | |
|           for(i=0; ALWAYS(i<p->x.pList->nExpr); i++){
 | |
|             if( ExprHasProperty(p->x.pList->a[i].pExpr, EP_Collate) ){
 | |
|               pNext = p->x.pList->a[i].pExpr;
 | |
|               break;
 | |
|             }
 | |
|           }
 | |
|         }
 | |
|         p = pNext;
 | |
|       }
 | |
|     }else{
 | |
|       break;
 | |
|     }
 | |
|   }
 | |
|   if( sqlite3CheckCollSeq(pParse, pColl) ){ 
 | |
|     pColl = 0;
 | |
|   }
 | |
|   return pColl;
 | |
| }
 | |
| 
 | |
| /*
 | |
| ** pExpr is an operand of a comparison operator.  aff2 is the
 | |
| ** type affinity of the other operand.  This routine returns the
 | |
| ** type affinity that should be used for the comparison operator.
 | |
| */
 | |
| char sqlite3CompareAffinity(Expr *pExpr, char aff2){
 | |
|   char aff1 = sqlite3ExprAffinity(pExpr);
 | |
|   if( aff1 && aff2 ){
 | |
|     /* Both sides of the comparison are columns. If one has numeric
 | |
|     ** affinity, use that. Otherwise use no affinity.
 | |
|     */
 | |
|     if( sqlite3IsNumericAffinity(aff1) || sqlite3IsNumericAffinity(aff2) ){
 | |
|       return SQLITE_AFF_NUMERIC;
 | |
|     }else{
 | |
|       return SQLITE_AFF_BLOB;
 | |
|     }
 | |
|   }else if( !aff1 && !aff2 ){
 | |
|     /* Neither side of the comparison is a column.  Compare the
 | |
|     ** results directly.
 | |
|     */
 | |
|     return SQLITE_AFF_BLOB;
 | |
|   }else{
 | |
|     /* One side is a column, the other is not. Use the columns affinity. */
 | |
|     assert( aff1==0 || aff2==0 );
 | |
|     return (aff1 + aff2);
 | |
|   }
 | |
| }
 | |
| 
 | |
| /*
 | |
| ** pExpr is a comparison operator.  Return the type affinity that should
 | |
| ** be applied to both operands prior to doing the comparison.
 | |
| */
 | |
| static char comparisonAffinity(Expr *pExpr){
 | |
|   char aff;
 | |
|   assert( pExpr->op==TK_EQ || pExpr->op==TK_IN || pExpr->op==TK_LT ||
 | |
|           pExpr->op==TK_GT || pExpr->op==TK_GE || pExpr->op==TK_LE ||
 | |
|           pExpr->op==TK_NE || pExpr->op==TK_IS || pExpr->op==TK_ISNOT );
 | |
|   assert( pExpr->pLeft );
 | |
|   aff = sqlite3ExprAffinity(pExpr->pLeft);
 | |
|   if( pExpr->pRight ){
 | |
|     aff = sqlite3CompareAffinity(pExpr->pRight, aff);
 | |
|   }else if( ExprHasProperty(pExpr, EP_xIsSelect) ){
 | |
|     aff = sqlite3CompareAffinity(pExpr->x.pSelect->pEList->a[0].pExpr, aff);
 | |
|   }else if( !aff ){
 | |
|     aff = SQLITE_AFF_BLOB;
 | |
|   }
 | |
|   return aff;
 | |
| }
 | |
| 
 | |
| /*
 | |
| ** pExpr is a comparison expression, eg. '=', '<', IN(...) etc.
 | |
| ** idx_affinity is the affinity of an indexed column. Return true
 | |
| ** if the index with affinity idx_affinity may be used to implement
 | |
| ** the comparison in pExpr.
 | |
| */
 | |
| int sqlite3IndexAffinityOk(Expr *pExpr, char idx_affinity){
 | |
|   char aff = comparisonAffinity(pExpr);
 | |
|   switch( aff ){
 | |
|     case SQLITE_AFF_BLOB:
 | |
|       return 1;
 | |
|     case SQLITE_AFF_TEXT:
 | |
|       return idx_affinity==SQLITE_AFF_TEXT;
 | |
|     default:
 | |
|       return sqlite3IsNumericAffinity(idx_affinity);
 | |
|   }
 | |
| }
 | |
| 
 | |
| /*
 | |
| ** Return the P5 value that should be used for a binary comparison
 | |
| ** opcode (OP_Eq, OP_Ge etc.) used to compare pExpr1 and pExpr2.
 | |
| */
 | |
| static u8 binaryCompareP5(Expr *pExpr1, Expr *pExpr2, int jumpIfNull){
 | |
|   u8 aff = (char)sqlite3ExprAffinity(pExpr2);
 | |
|   aff = (u8)sqlite3CompareAffinity(pExpr1, aff) | (u8)jumpIfNull;
 | |
|   return aff;
 | |
| }
 | |
| 
 | |
| /*
 | |
| ** Return a pointer to the collation sequence that should be used by
 | |
| ** a binary comparison operator comparing pLeft and pRight.
 | |
| **
 | |
| ** If the left hand expression has a collating sequence type, then it is
 | |
| ** used. Otherwise the collation sequence for the right hand expression
 | |
| ** is used, or the default (BINARY) if neither expression has a collating
 | |
| ** type.
 | |
| **
 | |
| ** Argument pRight (but not pLeft) may be a null pointer. In this case,
 | |
| ** it is not considered.
 | |
| */
 | |
| CollSeq *sqlite3BinaryCompareCollSeq(
 | |
|   Parse *pParse, 
 | |
|   Expr *pLeft, 
 | |
|   Expr *pRight
 | |
| ){
 | |
|   CollSeq *pColl;
 | |
|   assert( pLeft );
 | |
|   if( pLeft->flags & EP_Collate ){
 | |
|     pColl = sqlite3ExprCollSeq(pParse, pLeft);
 | |
|   }else if( pRight && (pRight->flags & EP_Collate)!=0 ){
 | |
|     pColl = sqlite3ExprCollSeq(pParse, pRight);
 | |
|   }else{
 | |
|     pColl = sqlite3ExprCollSeq(pParse, pLeft);
 | |
|     if( !pColl ){
 | |
|       pColl = sqlite3ExprCollSeq(pParse, pRight);
 | |
|     }
 | |
|   }
 | |
|   return pColl;
 | |
| }
 | |
| 
 | |
| /*
 | |
| ** Generate code for a comparison operator.
 | |
| */
 | |
| static int codeCompare(
 | |
|   Parse *pParse,    /* The parsing (and code generating) context */
 | |
|   Expr *pLeft,      /* The left operand */
 | |
|   Expr *pRight,     /* The right operand */
 | |
|   int opcode,       /* The comparison opcode */
 | |
|   int in1, int in2, /* Register holding operands */
 | |
|   int dest,         /* Jump here if true.  */
 | |
|   int jumpIfNull    /* If true, jump if either operand is NULL */
 | |
| ){
 | |
|   int p5;
 | |
|   int addr;
 | |
|   CollSeq *p4;
 | |
| 
 | |
|   p4 = sqlite3BinaryCompareCollSeq(pParse, pLeft, pRight);
 | |
|   p5 = binaryCompareP5(pLeft, pRight, jumpIfNull);
 | |
|   addr = sqlite3VdbeAddOp4(pParse->pVdbe, opcode, in2, dest, in1,
 | |
|                            (void*)p4, P4_COLLSEQ);
 | |
|   sqlite3VdbeChangeP5(pParse->pVdbe, (u8)p5);
 | |
|   return addr;
 | |
| }
 | |
| 
 | |
| #if SQLITE_MAX_EXPR_DEPTH>0
 | |
| /*
 | |
| ** Check that argument nHeight is less than or equal to the maximum
 | |
| ** expression depth allowed. If it is not, leave an error message in
 | |
| ** pParse.
 | |
| */
 | |
| int sqlite3ExprCheckHeight(Parse *pParse, int nHeight){
 | |
|   int rc = SQLITE_OK;
 | |
|   int mxHeight = pParse->db->aLimit[SQLITE_LIMIT_EXPR_DEPTH];
 | |
|   if( nHeight>mxHeight ){
 | |
|     sqlite3ErrorMsg(pParse, 
 | |
|        "Expression tree is too large (maximum depth %d)", mxHeight
 | |
|     );
 | |
|     rc = SQLITE_ERROR;
 | |
|   }
 | |
|   return rc;
 | |
| }
 | |
| 
 | |
| /* The following three functions, heightOfExpr(), heightOfExprList()
 | |
| ** and heightOfSelect(), are used to determine the maximum height
 | |
| ** of any expression tree referenced by the structure passed as the
 | |
| ** first argument.
 | |
| **
 | |
| ** If this maximum height is greater than the current value pointed
 | |
| ** to by pnHeight, the second parameter, then set *pnHeight to that
 | |
| ** value.
 | |
| */
 | |
| static void heightOfExpr(Expr *p, int *pnHeight){
 | |
|   if( p ){
 | |
|     if( p->nHeight>*pnHeight ){
 | |
|       *pnHeight = p->nHeight;
 | |
|     }
 | |
|   }
 | |
| }
 | |
| static void heightOfExprList(ExprList *p, int *pnHeight){
 | |
|   if( p ){
 | |
|     int i;
 | |
|     for(i=0; i<p->nExpr; i++){
 | |
|       heightOfExpr(p->a[i].pExpr, pnHeight);
 | |
|     }
 | |
|   }
 | |
| }
 | |
| static void heightOfSelect(Select *p, int *pnHeight){
 | |
|   if( p ){
 | |
|     heightOfExpr(p->pWhere, pnHeight);
 | |
|     heightOfExpr(p->pHaving, pnHeight);
 | |
|     heightOfExpr(p->pLimit, pnHeight);
 | |
|     heightOfExpr(p->pOffset, pnHeight);
 | |
|     heightOfExprList(p->pEList, pnHeight);
 | |
|     heightOfExprList(p->pGroupBy, pnHeight);
 | |
|     heightOfExprList(p->pOrderBy, pnHeight);
 | |
|     heightOfSelect(p->pPrior, pnHeight);
 | |
|   }
 | |
| }
 | |
| 
 | |
| /*
 | |
| ** Set the Expr.nHeight variable in the structure passed as an 
 | |
| ** argument. An expression with no children, Expr.pList or 
 | |
| ** Expr.pSelect member has a height of 1. Any other expression
 | |
| ** has a height equal to the maximum height of any other 
 | |
| ** referenced Expr plus one.
 | |
| **
 | |
| ** Also propagate EP_Propagate flags up from Expr.x.pList to Expr.flags,
 | |
| ** if appropriate.
 | |
| */
 | |
| static void exprSetHeight(Expr *p){
 | |
|   int nHeight = 0;
 | |
|   heightOfExpr(p->pLeft, &nHeight);
 | |
|   heightOfExpr(p->pRight, &nHeight);
 | |
|   if( ExprHasProperty(p, EP_xIsSelect) ){
 | |
|     heightOfSelect(p->x.pSelect, &nHeight);
 | |
|   }else if( p->x.pList ){
 | |
|     heightOfExprList(p->x.pList, &nHeight);
 | |
|     p->flags |= EP_Propagate & sqlite3ExprListFlags(p->x.pList);
 | |
|   }
 | |
|   p->nHeight = nHeight + 1;
 | |
| }
 | |
| 
 | |
| /*
 | |
| ** Set the Expr.nHeight variable using the exprSetHeight() function. If
 | |
| ** the height is greater than the maximum allowed expression depth,
 | |
| ** leave an error in pParse.
 | |
| **
 | |
| ** Also propagate all EP_Propagate flags from the Expr.x.pList into
 | |
| ** Expr.flags. 
 | |
| */
 | |
| void sqlite3ExprSetHeightAndFlags(Parse *pParse, Expr *p){
 | |
|   if( pParse->nErr ) return;
 | |
|   exprSetHeight(p);
 | |
|   sqlite3ExprCheckHeight(pParse, p->nHeight);
 | |
| }
 | |
| 
 | |
| /*
 | |
| ** Return the maximum height of any expression tree referenced
 | |
| ** by the select statement passed as an argument.
 | |
| */
 | |
| int sqlite3SelectExprHeight(Select *p){
 | |
|   int nHeight = 0;
 | |
|   heightOfSelect(p, &nHeight);
 | |
|   return nHeight;
 | |
| }
 | |
| #else /* ABOVE:  Height enforcement enabled.  BELOW: Height enforcement off */
 | |
| /*
 | |
| ** Propagate all EP_Propagate flags from the Expr.x.pList into
 | |
| ** Expr.flags. 
 | |
| */
 | |
| void sqlite3ExprSetHeightAndFlags(Parse *pParse, Expr *p){
 | |
|   if( p && p->x.pList && !ExprHasProperty(p, EP_xIsSelect) ){
 | |
|     p->flags |= EP_Propagate & sqlite3ExprListFlags(p->x.pList);
 | |
|   }
 | |
| }
 | |
| #define exprSetHeight(y)
 | |
| #endif /* SQLITE_MAX_EXPR_DEPTH>0 */
 | |
| 
 | |
| /*
 | |
| ** This routine is the core allocator for Expr nodes.
 | |
| **
 | |
| ** Construct a new expression node and return a pointer to it.  Memory
 | |
| ** for this node and for the pToken argument is a single allocation
 | |
| ** obtained from sqlite3DbMalloc().  The calling function
 | |
| ** is responsible for making sure the node eventually gets freed.
 | |
| **
 | |
| ** If dequote is true, then the token (if it exists) is dequoted.
 | |
| ** If dequote is false, no dequoting is performed.  The deQuote
 | |
| ** parameter is ignored if pToken is NULL or if the token does not
 | |
| ** appear to be quoted.  If the quotes were of the form "..." (double-quotes)
 | |
| ** then the EP_DblQuoted flag is set on the expression node.
 | |
| **
 | |
| ** Special case:  If op==TK_INTEGER and pToken points to a string that
 | |
| ** can be translated into a 32-bit integer, then the token is not
 | |
| ** stored in u.zToken.  Instead, the integer values is written
 | |
| ** into u.iValue and the EP_IntValue flag is set.  No extra storage
 | |
| ** is allocated to hold the integer text and the dequote flag is ignored.
 | |
| */
 | |
| Expr *sqlite3ExprAlloc(
 | |
|   sqlite3 *db,            /* Handle for sqlite3DbMallocZero() (may be null) */
 | |
|   int op,                 /* Expression opcode */
 | |
|   const Token *pToken,    /* Token argument.  Might be NULL */
 | |
|   int dequote             /* True to dequote */
 | |
| ){
 | |
|   Expr *pNew;
 | |
|   int nExtra = 0;
 | |
|   int iValue = 0;
 | |
| 
 | |
|   assert( db!=0 );
 | |
|   if( pToken ){
 | |
|     if( op!=TK_INTEGER || pToken->z==0
 | |
|           || sqlite3GetInt32(pToken->z, &iValue)==0 ){
 | |
|       nExtra = pToken->n+1;
 | |
|       assert( iValue>=0 );
 | |
|     }
 | |
|   }
 | |
|   pNew = sqlite3DbMallocRawNN(db, sizeof(Expr)+nExtra);
 | |
|   if( pNew ){
 | |
|     memset(pNew, 0, sizeof(Expr));
 | |
|     pNew->op = (u8)op;
 | |
|     pNew->iAgg = -1;
 | |
|     if( pToken ){
 | |
|       if( nExtra==0 ){
 | |
|         pNew->flags |= EP_IntValue;
 | |
|         pNew->u.iValue = iValue;
 | |
|       }else{
 | |
|         int c;
 | |
|         pNew->u.zToken = (char*)&pNew[1];
 | |
|         assert( pToken->z!=0 || pToken->n==0 );
 | |
|         if( pToken->n ) memcpy(pNew->u.zToken, pToken->z, pToken->n);
 | |
|         pNew->u.zToken[pToken->n] = 0;
 | |
|         if( dequote && nExtra>=3 
 | |
|              && ((c = pToken->z[0])=='\'' || c=='"' || c=='[' || c=='`') ){
 | |
|           sqlite3Dequote(pNew->u.zToken);
 | |
|           if( c=='"' ) pNew->flags |= EP_DblQuoted;
 | |
|         }
 | |
|       }
 | |
|     }
 | |
| #if SQLITE_MAX_EXPR_DEPTH>0
 | |
|     pNew->nHeight = 1;
 | |
| #endif  
 | |
|   }
 | |
|   return pNew;
 | |
| }
 | |
| 
 | |
| /*
 | |
| ** Allocate a new expression node from a zero-terminated token that has
 | |
| ** already been dequoted.
 | |
| */
 | |
| Expr *sqlite3Expr(
 | |
|   sqlite3 *db,            /* Handle for sqlite3DbMallocZero() (may be null) */
 | |
|   int op,                 /* Expression opcode */
 | |
|   const char *zToken      /* Token argument.  Might be NULL */
 | |
| ){
 | |
|   Token x;
 | |
|   x.z = zToken;
 | |
|   x.n = zToken ? sqlite3Strlen30(zToken) : 0;
 | |
|   return sqlite3ExprAlloc(db, op, &x, 0);
 | |
| }
 | |
| 
 | |
| /*
 | |
| ** Attach subtrees pLeft and pRight to the Expr node pRoot.
 | |
| **
 | |
| ** If pRoot==NULL that means that a memory allocation error has occurred.
 | |
| ** In that case, delete the subtrees pLeft and pRight.
 | |
| */
 | |
| void sqlite3ExprAttachSubtrees(
 | |
|   sqlite3 *db,
 | |
|   Expr *pRoot,
 | |
|   Expr *pLeft,
 | |
|   Expr *pRight
 | |
| ){
 | |
|   if( pRoot==0 ){
 | |
|     assert( db->mallocFailed );
 | |
|     sqlite3ExprDelete(db, pLeft);
 | |
|     sqlite3ExprDelete(db, pRight);
 | |
|   }else{
 | |
|     if( pRight ){
 | |
|       pRoot->pRight = pRight;
 | |
|       pRoot->flags |= EP_Propagate & pRight->flags;
 | |
|     }
 | |
|     if( pLeft ){
 | |
|       pRoot->pLeft = pLeft;
 | |
|       pRoot->flags |= EP_Propagate & pLeft->flags;
 | |
|     }
 | |
|     exprSetHeight(pRoot);
 | |
|   }
 | |
| }
 | |
| 
 | |
| /*
 | |
| ** Allocate an Expr node which joins as many as two subtrees.
 | |
| **
 | |
| ** One or both of the subtrees can be NULL.  Return a pointer to the new
 | |
| ** Expr node.  Or, if an OOM error occurs, set pParse->db->mallocFailed,
 | |
| ** free the subtrees and return NULL.
 | |
| */
 | |
| Expr *sqlite3PExpr(
 | |
|   Parse *pParse,          /* Parsing context */
 | |
|   int op,                 /* Expression opcode */
 | |
|   Expr *pLeft,            /* Left operand */
 | |
|   Expr *pRight,           /* Right operand */
 | |
|   const Token *pToken     /* Argument token */
 | |
| ){
 | |
|   Expr *p;
 | |
|   if( op==TK_AND && pParse->nErr==0 ){
 | |
|     /* Take advantage of short-circuit false optimization for AND */
 | |
|     p = sqlite3ExprAnd(pParse->db, pLeft, pRight);
 | |
|   }else{
 | |
|     p = sqlite3ExprAlloc(pParse->db, op & TKFLG_MASK, pToken, 1);
 | |
|     sqlite3ExprAttachSubtrees(pParse->db, p, pLeft, pRight);
 | |
|   }
 | |
|   if( p ) {
 | |
|     sqlite3ExprCheckHeight(pParse, p->nHeight);
 | |
|   }
 | |
|   return p;
 | |
| }
 | |
| 
 | |
| /*
 | |
| ** If the expression is always either TRUE or FALSE (respectively),
 | |
| ** then return 1.  If one cannot determine the truth value of the
 | |
| ** expression at compile-time return 0.
 | |
| **
 | |
| ** This is an optimization.  If is OK to return 0 here even if
 | |
| ** the expression really is always false or false (a false negative).
 | |
| ** But it is a bug to return 1 if the expression might have different
 | |
| ** boolean values in different circumstances (a false positive.)
 | |
| **
 | |
| ** Note that if the expression is part of conditional for a
 | |
| ** LEFT JOIN, then we cannot determine at compile-time whether or not
 | |
| ** is it true or false, so always return 0.
 | |
| */
 | |
| static int exprAlwaysTrue(Expr *p){
 | |
|   int v = 0;
 | |
|   if( ExprHasProperty(p, EP_FromJoin) ) return 0;
 | |
|   if( !sqlite3ExprIsInteger(p, &v) ) return 0;
 | |
|   return v!=0;
 | |
| }
 | |
| static int exprAlwaysFalse(Expr *p){
 | |
|   int v = 0;
 | |
|   if( ExprHasProperty(p, EP_FromJoin) ) return 0;
 | |
|   if( !sqlite3ExprIsInteger(p, &v) ) return 0;
 | |
|   return v==0;
 | |
| }
 | |
| 
 | |
| /*
 | |
| ** Join two expressions using an AND operator.  If either expression is
 | |
| ** NULL, then just return the other expression.
 | |
| **
 | |
| ** If one side or the other of the AND is known to be false, then instead
 | |
| ** of returning an AND expression, just return a constant expression with
 | |
| ** a value of false.
 | |
| */
 | |
| Expr *sqlite3ExprAnd(sqlite3 *db, Expr *pLeft, Expr *pRight){
 | |
|   if( pLeft==0 ){
 | |
|     return pRight;
 | |
|   }else if( pRight==0 ){
 | |
|     return pLeft;
 | |
|   }else if( exprAlwaysFalse(pLeft) || exprAlwaysFalse(pRight) ){
 | |
|     sqlite3ExprDelete(db, pLeft);
 | |
|     sqlite3ExprDelete(db, pRight);
 | |
|     return sqlite3ExprAlloc(db, TK_INTEGER, &sqlite3IntTokens[0], 0);
 | |
|   }else{
 | |
|     Expr *pNew = sqlite3ExprAlloc(db, TK_AND, 0, 0);
 | |
|     sqlite3ExprAttachSubtrees(db, pNew, pLeft, pRight);
 | |
|     return pNew;
 | |
|   }
 | |
| }
 | |
| 
 | |
| /*
 | |
| ** Construct a new expression node for a function with multiple
 | |
| ** arguments.
 | |
| */
 | |
| Expr *sqlite3ExprFunction(Parse *pParse, ExprList *pList, Token *pToken){
 | |
|   Expr *pNew;
 | |
|   sqlite3 *db = pParse->db;
 | |
|   assert( pToken );
 | |
|   pNew = sqlite3ExprAlloc(db, TK_FUNCTION, pToken, 1);
 | |
|   if( pNew==0 ){
 | |
|     sqlite3ExprListDelete(db, pList); /* Avoid memory leak when malloc fails */
 | |
|     return 0;
 | |
|   }
 | |
|   pNew->x.pList = pList;
 | |
|   assert( !ExprHasProperty(pNew, EP_xIsSelect) );
 | |
|   sqlite3ExprSetHeightAndFlags(pParse, pNew);
 | |
|   return pNew;
 | |
| }
 | |
| 
 | |
| /*
 | |
| ** Assign a variable number to an expression that encodes a wildcard
 | |
| ** in the original SQL statement.  
 | |
| **
 | |
| ** Wildcards consisting of a single "?" are assigned the next sequential
 | |
| ** variable number.
 | |
| **
 | |
| ** Wildcards of the form "?nnn" are assigned the number "nnn".  We make
 | |
| ** sure "nnn" is not too be to avoid a denial of service attack when
 | |
| ** the SQL statement comes from an external source.
 | |
| **
 | |
| ** Wildcards of the form ":aaa", "@aaa", or "$aaa" are assigned the same number
 | |
| ** as the previous instance of the same wildcard.  Or if this is the first
 | |
| ** instance of the wildcard, the next sequential variable number is
 | |
| ** assigned.
 | |
| */
 | |
| void sqlite3ExprAssignVarNumber(Parse *pParse, Expr *pExpr){
 | |
|   sqlite3 *db = pParse->db;
 | |
|   const char *z;
 | |
| 
 | |
|   if( pExpr==0 ) return;
 | |
|   assert( !ExprHasProperty(pExpr, EP_IntValue|EP_Reduced|EP_TokenOnly) );
 | |
|   z = pExpr->u.zToken;
 | |
|   assert( z!=0 );
 | |
|   assert( z[0]!=0 );
 | |
|   if( z[1]==0 ){
 | |
|     /* Wildcard of the form "?".  Assign the next variable number */
 | |
|     assert( z[0]=='?' );
 | |
|     pExpr->iColumn = (ynVar)(++pParse->nVar);
 | |
|   }else{
 | |
|     ynVar x = 0;
 | |
|     u32 n = sqlite3Strlen30(z);
 | |
|     if( z[0]=='?' ){
 | |
|       /* Wildcard of the form "?nnn".  Convert "nnn" to an integer and
 | |
|       ** use it as the variable number */
 | |
|       i64 i;
 | |
|       int bOk = 0==sqlite3Atoi64(&z[1], &i, n-1, SQLITE_UTF8);
 | |
|       pExpr->iColumn = x = (ynVar)i;
 | |
|       testcase( i==0 );
 | |
|       testcase( i==1 );
 | |
|       testcase( i==db->aLimit[SQLITE_LIMIT_VARIABLE_NUMBER]-1 );
 | |
|       testcase( i==db->aLimit[SQLITE_LIMIT_VARIABLE_NUMBER] );
 | |
|       if( bOk==0 || i<1 || i>db->aLimit[SQLITE_LIMIT_VARIABLE_NUMBER] ){
 | |
|         sqlite3ErrorMsg(pParse, "variable number must be between ?1 and ?%d",
 | |
|             db->aLimit[SQLITE_LIMIT_VARIABLE_NUMBER]);
 | |
|         x = 0;
 | |
|       }
 | |
|       if( i>pParse->nVar ){
 | |
|         pParse->nVar = (int)i;
 | |
|       }
 | |
|     }else{
 | |
|       /* Wildcards like ":aaa", "$aaa" or "@aaa".  Reuse the same variable
 | |
|       ** number as the prior appearance of the same name, or if the name
 | |
|       ** has never appeared before, reuse the same variable number
 | |
|       */
 | |
|       ynVar i;
 | |
|       for(i=0; i<pParse->nzVar; i++){
 | |
|         if( pParse->azVar[i] && strcmp(pParse->azVar[i],z)==0 ){
 | |
|           pExpr->iColumn = x = (ynVar)i+1;
 | |
|           break;
 | |
|         }
 | |
|       }
 | |
|       if( x==0 ) x = pExpr->iColumn = (ynVar)(++pParse->nVar);
 | |
|     }
 | |
|     if( x>0 ){
 | |
|       if( x>pParse->nzVar ){
 | |
|         char **a;
 | |
|         a = sqlite3DbRealloc(db, pParse->azVar, x*sizeof(a[0]));
 | |
|         if( a==0 ){
 | |
|           assert( db->mallocFailed ); /* Error reported through mallocFailed */
 | |
|           return;
 | |
|         }
 | |
|         pParse->azVar = a;
 | |
|         memset(&a[pParse->nzVar], 0, (x-pParse->nzVar)*sizeof(a[0]));
 | |
|         pParse->nzVar = x;
 | |
|       }
 | |
|       if( z[0]!='?' || pParse->azVar[x-1]==0 ){
 | |
|         sqlite3DbFree(db, pParse->azVar[x-1]);
 | |
|         pParse->azVar[x-1] = sqlite3DbStrNDup(db, z, n);
 | |
|       }
 | |
|     }
 | |
|   } 
 | |
|   if( !pParse->nErr && pParse->nVar>db->aLimit[SQLITE_LIMIT_VARIABLE_NUMBER] ){
 | |
|     sqlite3ErrorMsg(pParse, "too many SQL variables");
 | |
|   }
 | |
| }
 | |
| 
 | |
| /*
 | |
| ** Recursively delete an expression tree.
 | |
| */
 | |
| void sqlite3ExprDelete(sqlite3 *db, Expr *p){
 | |
|   if( p==0 ) return;
 | |
|   /* Sanity check: Assert that the IntValue is non-negative if it exists */
 | |
|   assert( !ExprHasProperty(p, EP_IntValue) || p->u.iValue>=0 );
 | |
|   if( !ExprHasProperty(p, EP_TokenOnly) ){
 | |
|     /* The Expr.x union is never used at the same time as Expr.pRight */
 | |
|     assert( p->x.pList==0 || p->pRight==0 );
 | |
|     sqlite3ExprDelete(db, p->pLeft);
 | |
|     sqlite3ExprDelete(db, p->pRight);
 | |
|     if( ExprHasProperty(p, EP_MemToken) ) sqlite3DbFree(db, p->u.zToken);
 | |
|     if( ExprHasProperty(p, EP_xIsSelect) ){
 | |
|       sqlite3SelectDelete(db, p->x.pSelect);
 | |
|     }else{
 | |
|       sqlite3ExprListDelete(db, p->x.pList);
 | |
|     }
 | |
|   }
 | |
|   if( !ExprHasProperty(p, EP_Static) ){
 | |
|     sqlite3DbFree(db, p);
 | |
|   }
 | |
| }
 | |
| 
 | |
| /*
 | |
| ** Return the number of bytes allocated for the expression structure 
 | |
| ** passed as the first argument. This is always one of EXPR_FULLSIZE,
 | |
| ** EXPR_REDUCEDSIZE or EXPR_TOKENONLYSIZE.
 | |
| */
 | |
| static int exprStructSize(Expr *p){
 | |
|   if( ExprHasProperty(p, EP_TokenOnly) ) return EXPR_TOKENONLYSIZE;
 | |
|   if( ExprHasProperty(p, EP_Reduced) ) return EXPR_REDUCEDSIZE;
 | |
|   return EXPR_FULLSIZE;
 | |
| }
 | |
| 
 | |
| /*
 | |
| ** The dupedExpr*Size() routines each return the number of bytes required
 | |
| ** to store a copy of an expression or expression tree.  They differ in
 | |
| ** how much of the tree is measured.
 | |
| **
 | |
| **     dupedExprStructSize()     Size of only the Expr structure 
 | |
| **     dupedExprNodeSize()       Size of Expr + space for token
 | |
| **     dupedExprSize()           Expr + token + subtree components
 | |
| **
 | |
| ***************************************************************************
 | |
| **
 | |
| ** The dupedExprStructSize() function returns two values OR-ed together:  
 | |
| ** (1) the space required for a copy of the Expr structure only and 
 | |
| ** (2) the EP_xxx flags that indicate what the structure size should be.
 | |
| ** The return values is always one of:
 | |
| **
 | |
| **      EXPR_FULLSIZE
 | |
| **      EXPR_REDUCEDSIZE   | EP_Reduced
 | |
| **      EXPR_TOKENONLYSIZE | EP_TokenOnly
 | |
| **
 | |
| ** The size of the structure can be found by masking the return value
 | |
| ** of this routine with 0xfff.  The flags can be found by masking the
 | |
| ** return value with EP_Reduced|EP_TokenOnly.
 | |
| **
 | |
| ** Note that with flags==EXPRDUP_REDUCE, this routines works on full-size
 | |
| ** (unreduced) Expr objects as they or originally constructed by the parser.
 | |
| ** During expression analysis, extra information is computed and moved into
 | |
| ** later parts of teh Expr object and that extra information might get chopped
 | |
| ** off if the expression is reduced.  Note also that it does not work to
 | |
| ** make an EXPRDUP_REDUCE copy of a reduced expression.  It is only legal
 | |
| ** to reduce a pristine expression tree from the parser.  The implementation
 | |
| ** of dupedExprStructSize() contain multiple assert() statements that attempt
 | |
| ** to enforce this constraint.
 | |
| */
 | |
| static int dupedExprStructSize(Expr *p, int flags){
 | |
|   int nSize;
 | |
|   assert( flags==EXPRDUP_REDUCE || flags==0 ); /* Only one flag value allowed */
 | |
|   assert( EXPR_FULLSIZE<=0xfff );
 | |
|   assert( (0xfff & (EP_Reduced|EP_TokenOnly))==0 );
 | |
|   if( 0==(flags&EXPRDUP_REDUCE) ){
 | |
|     nSize = EXPR_FULLSIZE;
 | |
|   }else{
 | |
|     assert( !ExprHasProperty(p, EP_TokenOnly|EP_Reduced) );
 | |
|     assert( !ExprHasProperty(p, EP_FromJoin) ); 
 | |
|     assert( !ExprHasProperty(p, EP_MemToken) );
 | |
|     assert( !ExprHasProperty(p, EP_NoReduce) );
 | |
|     if( p->pLeft || p->x.pList ){
 | |
|       nSize = EXPR_REDUCEDSIZE | EP_Reduced;
 | |
|     }else{
 | |
|       assert( p->pRight==0 );
 | |
|       nSize = EXPR_TOKENONLYSIZE | EP_TokenOnly;
 | |
|     }
 | |
|   }
 | |
|   return nSize;
 | |
| }
 | |
| 
 | |
| /*
 | |
| ** This function returns the space in bytes required to store the copy 
 | |
| ** of the Expr structure and a copy of the Expr.u.zToken string (if that
 | |
| ** string is defined.)
 | |
| */
 | |
| static int dupedExprNodeSize(Expr *p, int flags){
 | |
|   int nByte = dupedExprStructSize(p, flags) & 0xfff;
 | |
|   if( !ExprHasProperty(p, EP_IntValue) && p->u.zToken ){
 | |
|     nByte += sqlite3Strlen30(p->u.zToken)+1;
 | |
|   }
 | |
|   return ROUND8(nByte);
 | |
| }
 | |
| 
 | |
| /*
 | |
| ** Return the number of bytes required to create a duplicate of the 
 | |
| ** expression passed as the first argument. The second argument is a
 | |
| ** mask containing EXPRDUP_XXX flags.
 | |
| **
 | |
| ** The value returned includes space to create a copy of the Expr struct
 | |
| ** itself and the buffer referred to by Expr.u.zToken, if any.
 | |
| **
 | |
| ** If the EXPRDUP_REDUCE flag is set, then the return value includes 
 | |
| ** space to duplicate all Expr nodes in the tree formed by Expr.pLeft 
 | |
| ** and Expr.pRight variables (but not for any structures pointed to or 
 | |
| ** descended from the Expr.x.pList or Expr.x.pSelect variables).
 | |
| */
 | |
| static int dupedExprSize(Expr *p, int flags){
 | |
|   int nByte = 0;
 | |
|   if( p ){
 | |
|     nByte = dupedExprNodeSize(p, flags);
 | |
|     if( flags&EXPRDUP_REDUCE ){
 | |
|       nByte += dupedExprSize(p->pLeft, flags) + dupedExprSize(p->pRight, flags);
 | |
|     }
 | |
|   }
 | |
|   return nByte;
 | |
| }
 | |
| 
 | |
| /*
 | |
| ** This function is similar to sqlite3ExprDup(), except that if pzBuffer 
 | |
| ** is not NULL then *pzBuffer is assumed to point to a buffer large enough 
 | |
| ** to store the copy of expression p, the copies of p->u.zToken
 | |
| ** (if applicable), and the copies of the p->pLeft and p->pRight expressions,
 | |
| ** if any. Before returning, *pzBuffer is set to the first byte past the
 | |
| ** portion of the buffer copied into by this function.
 | |
| */
 | |
| static Expr *exprDup(sqlite3 *db, Expr *p, int flags, u8 **pzBuffer){
 | |
|   Expr *pNew = 0;                      /* Value to return */
 | |
|   assert( flags==0 || flags==EXPRDUP_REDUCE );
 | |
|   assert( db!=0 );
 | |
|   if( p ){
 | |
|     const int isReduced = (flags&EXPRDUP_REDUCE);
 | |
|     u8 *zAlloc;
 | |
|     u32 staticFlag = 0;
 | |
| 
 | |
|     assert( pzBuffer==0 || isReduced );
 | |
| 
 | |
|     /* Figure out where to write the new Expr structure. */
 | |
|     if( pzBuffer ){
 | |
|       zAlloc = *pzBuffer;
 | |
|       staticFlag = EP_Static;
 | |
|     }else{
 | |
|       zAlloc = sqlite3DbMallocRawNN(db, dupedExprSize(p, flags));
 | |
|     }
 | |
|     pNew = (Expr *)zAlloc;
 | |
| 
 | |
|     if( pNew ){
 | |
|       /* Set nNewSize to the size allocated for the structure pointed to
 | |
|       ** by pNew. This is either EXPR_FULLSIZE, EXPR_REDUCEDSIZE or
 | |
|       ** EXPR_TOKENONLYSIZE. nToken is set to the number of bytes consumed
 | |
|       ** by the copy of the p->u.zToken string (if any).
 | |
|       */
 | |
|       const unsigned nStructSize = dupedExprStructSize(p, flags);
 | |
|       const int nNewSize = nStructSize & 0xfff;
 | |
|       int nToken;
 | |
|       if( !ExprHasProperty(p, EP_IntValue) && p->u.zToken ){
 | |
|         nToken = sqlite3Strlen30(p->u.zToken) + 1;
 | |
|       }else{
 | |
|         nToken = 0;
 | |
|       }
 | |
|       if( isReduced ){
 | |
|         assert( ExprHasProperty(p, EP_Reduced)==0 );
 | |
|         memcpy(zAlloc, p, nNewSize);
 | |
|       }else{
 | |
|         u32 nSize = (u32)exprStructSize(p);
 | |
|         memcpy(zAlloc, p, nSize);
 | |
|         if( nSize<EXPR_FULLSIZE ){ 
 | |
|           memset(&zAlloc[nSize], 0, EXPR_FULLSIZE-nSize);
 | |
|         }
 | |
|       }
 | |
| 
 | |
|       /* Set the EP_Reduced, EP_TokenOnly, and EP_Static flags appropriately. */
 | |
|       pNew->flags &= ~(EP_Reduced|EP_TokenOnly|EP_Static|EP_MemToken);
 | |
|       pNew->flags |= nStructSize & (EP_Reduced|EP_TokenOnly);
 | |
|       pNew->flags |= staticFlag;
 | |
| 
 | |
|       /* Copy the p->u.zToken string, if any. */
 | |
|       if( nToken ){
 | |
|         char *zToken = pNew->u.zToken = (char*)&zAlloc[nNewSize];
 | |
|         memcpy(zToken, p->u.zToken, nToken);
 | |
|       }
 | |
| 
 | |
|       if( 0==((p->flags|pNew->flags) & EP_TokenOnly) ){
 | |
|         /* Fill in the pNew->x.pSelect or pNew->x.pList member. */
 | |
|         if( ExprHasProperty(p, EP_xIsSelect) ){
 | |
|           pNew->x.pSelect = sqlite3SelectDup(db, p->x.pSelect, isReduced);
 | |
|         }else{
 | |
|           pNew->x.pList = sqlite3ExprListDup(db, p->x.pList, isReduced);
 | |
|         }
 | |
|       }
 | |
| 
 | |
|       /* Fill in pNew->pLeft and pNew->pRight. */
 | |
|       if( ExprHasProperty(pNew, EP_Reduced|EP_TokenOnly) ){
 | |
|         zAlloc += dupedExprNodeSize(p, flags);
 | |
|         if( ExprHasProperty(pNew, EP_Reduced) ){
 | |
|           pNew->pLeft = exprDup(db, p->pLeft, EXPRDUP_REDUCE, &zAlloc);
 | |
|           pNew->pRight = exprDup(db, p->pRight, EXPRDUP_REDUCE, &zAlloc);
 | |
|         }
 | |
|         if( pzBuffer ){
 | |
|           *pzBuffer = zAlloc;
 | |
|         }
 | |
|       }else{
 | |
|         if( !ExprHasProperty(p, EP_TokenOnly) ){
 | |
|           pNew->pLeft = sqlite3ExprDup(db, p->pLeft, 0);
 | |
|           pNew->pRight = sqlite3ExprDup(db, p->pRight, 0);
 | |
|         }
 | |
|       }
 | |
| 
 | |
|     }
 | |
|   }
 | |
|   return pNew;
 | |
| }
 | |
| 
 | |
| /*
 | |
| ** Create and return a deep copy of the object passed as the second 
 | |
| ** argument. If an OOM condition is encountered, NULL is returned
 | |
| ** and the db->mallocFailed flag set.
 | |
| */
 | |
| #ifndef SQLITE_OMIT_CTE
 | |
| static With *withDup(sqlite3 *db, With *p){
 | |
|   With *pRet = 0;
 | |
|   if( p ){
 | |
|     int nByte = sizeof(*p) + sizeof(p->a[0]) * (p->nCte-1);
 | |
|     pRet = sqlite3DbMallocZero(db, nByte);
 | |
|     if( pRet ){
 | |
|       int i;
 | |
|       pRet->nCte = p->nCte;
 | |
|       for(i=0; i<p->nCte; i++){
 | |
|         pRet->a[i].pSelect = sqlite3SelectDup(db, p->a[i].pSelect, 0);
 | |
|         pRet->a[i].pCols = sqlite3ExprListDup(db, p->a[i].pCols, 0);
 | |
|         pRet->a[i].zName = sqlite3DbStrDup(db, p->a[i].zName);
 | |
|       }
 | |
|     }
 | |
|   }
 | |
|   return pRet;
 | |
| }
 | |
| #else
 | |
| # define withDup(x,y) 0
 | |
| #endif
 | |
| 
 | |
| /*
 | |
| ** The following group of routines make deep copies of expressions,
 | |
| ** expression lists, ID lists, and select statements.  The copies can
 | |
| ** be deleted (by being passed to their respective ...Delete() routines)
 | |
| ** without effecting the originals.
 | |
| **
 | |
| ** The expression list, ID, and source lists return by sqlite3ExprListDup(),
 | |
| ** sqlite3IdListDup(), and sqlite3SrcListDup() can not be further expanded 
 | |
| ** by subsequent calls to sqlite*ListAppend() routines.
 | |
| **
 | |
| ** Any tables that the SrcList might point to are not duplicated.
 | |
| **
 | |
| ** The flags parameter contains a combination of the EXPRDUP_XXX flags.
 | |
| ** If the EXPRDUP_REDUCE flag is set, then the structure returned is a
 | |
| ** truncated version of the usual Expr structure that will be stored as
 | |
| ** part of the in-memory representation of the database schema.
 | |
| */
 | |
| Expr *sqlite3ExprDup(sqlite3 *db, Expr *p, int flags){
 | |
|   assert( flags==0 || flags==EXPRDUP_REDUCE );
 | |
|   return exprDup(db, p, flags, 0);
 | |
| }
 | |
| ExprList *sqlite3ExprListDup(sqlite3 *db, ExprList *p, int flags){
 | |
|   ExprList *pNew;
 | |
|   struct ExprList_item *pItem, *pOldItem;
 | |
|   int i;
 | |
|   assert( db!=0 );
 | |
|   if( p==0 ) return 0;
 | |
|   pNew = sqlite3DbMallocRawNN(db, sizeof(*pNew) );
 | |
|   if( pNew==0 ) return 0;
 | |
|   pNew->nExpr = i = p->nExpr;
 | |
|   if( (flags & EXPRDUP_REDUCE)==0 ) for(i=1; i<p->nExpr; i+=i){}
 | |
|   pNew->a = pItem = sqlite3DbMallocRawNN(db,  i*sizeof(p->a[0]) );
 | |
|   if( pItem==0 ){
 | |
|     sqlite3DbFree(db, pNew);
 | |
|     return 0;
 | |
|   } 
 | |
|   pOldItem = p->a;
 | |
|   for(i=0; i<p->nExpr; i++, pItem++, pOldItem++){
 | |
|     Expr *pOldExpr = pOldItem->pExpr;
 | |
|     pItem->pExpr = sqlite3ExprDup(db, pOldExpr, flags);
 | |
|     pItem->zName = sqlite3DbStrDup(db, pOldItem->zName);
 | |
|     pItem->zSpan = sqlite3DbStrDup(db, pOldItem->zSpan);
 | |
|     pItem->sortOrder = pOldItem->sortOrder;
 | |
|     pItem->done = 0;
 | |
|     pItem->bSpanIsTab = pOldItem->bSpanIsTab;
 | |
|     pItem->u = pOldItem->u;
 | |
|   }
 | |
|   return pNew;
 | |
| }
 | |
| 
 | |
| /*
 | |
| ** If cursors, triggers, views and subqueries are all omitted from
 | |
| ** the build, then none of the following routines, except for 
 | |
| ** sqlite3SelectDup(), can be called. sqlite3SelectDup() is sometimes
 | |
| ** called with a NULL argument.
 | |
| */
 | |
| #if !defined(SQLITE_OMIT_VIEW) || !defined(SQLITE_OMIT_TRIGGER) \
 | |
|  || !defined(SQLITE_OMIT_SUBQUERY)
 | |
| SrcList *sqlite3SrcListDup(sqlite3 *db, SrcList *p, int flags){
 | |
|   SrcList *pNew;
 | |
|   int i;
 | |
|   int nByte;
 | |
|   assert( db!=0 );
 | |
|   if( p==0 ) return 0;
 | |
|   nByte = sizeof(*p) + (p->nSrc>0 ? sizeof(p->a[0]) * (p->nSrc-1) : 0);
 | |
|   pNew = sqlite3DbMallocRawNN(db, nByte );
 | |
|   if( pNew==0 ) return 0;
 | |
|   pNew->nSrc = pNew->nAlloc = p->nSrc;
 | |
|   for(i=0; i<p->nSrc; i++){
 | |
|     struct SrcList_item *pNewItem = &pNew->a[i];
 | |
|     struct SrcList_item *pOldItem = &p->a[i];
 | |
|     Table *pTab;
 | |
|     pNewItem->pSchema = pOldItem->pSchema;
 | |
|     pNewItem->zDatabase = sqlite3DbStrDup(db, pOldItem->zDatabase);
 | |
|     pNewItem->zName = sqlite3DbStrDup(db, pOldItem->zName);
 | |
|     pNewItem->zAlias = sqlite3DbStrDup(db, pOldItem->zAlias);
 | |
|     pNewItem->fg = pOldItem->fg;
 | |
|     pNewItem->iCursor = pOldItem->iCursor;
 | |
|     pNewItem->addrFillSub = pOldItem->addrFillSub;
 | |
|     pNewItem->regReturn = pOldItem->regReturn;
 | |
|     if( pNewItem->fg.isIndexedBy ){
 | |
|       pNewItem->u1.zIndexedBy = sqlite3DbStrDup(db, pOldItem->u1.zIndexedBy);
 | |
|     }
 | |
|     pNewItem->pIBIndex = pOldItem->pIBIndex;
 | |
|     if( pNewItem->fg.isTabFunc ){
 | |
|       pNewItem->u1.pFuncArg = 
 | |
|           sqlite3ExprListDup(db, pOldItem->u1.pFuncArg, flags);
 | |
|     }
 | |
|     pTab = pNewItem->pTab = pOldItem->pTab;
 | |
|     if( pTab ){
 | |
|       pTab->nRef++;
 | |
|     }
 | |
|     pNewItem->pSelect = sqlite3SelectDup(db, pOldItem->pSelect, flags);
 | |
|     pNewItem->pOn = sqlite3ExprDup(db, pOldItem->pOn, flags);
 | |
|     pNewItem->pUsing = sqlite3IdListDup(db, pOldItem->pUsing);
 | |
|     pNewItem->colUsed = pOldItem->colUsed;
 | |
|   }
 | |
|   return pNew;
 | |
| }
 | |
| IdList *sqlite3IdListDup(sqlite3 *db, IdList *p){
 | |
|   IdList *pNew;
 | |
|   int i;
 | |
|   assert( db!=0 );
 | |
|   if( p==0 ) return 0;
 | |
|   pNew = sqlite3DbMallocRawNN(db, sizeof(*pNew) );
 | |
|   if( pNew==0 ) return 0;
 | |
|   pNew->nId = p->nId;
 | |
|   pNew->a = sqlite3DbMallocRawNN(db, p->nId*sizeof(p->a[0]) );
 | |
|   if( pNew->a==0 ){
 | |
|     sqlite3DbFree(db, pNew);
 | |
|     return 0;
 | |
|   }
 | |
|   /* Note that because the size of the allocation for p->a[] is not
 | |
|   ** necessarily a power of two, sqlite3IdListAppend() may not be called
 | |
|   ** on the duplicate created by this function. */
 | |
|   for(i=0; i<p->nId; i++){
 | |
|     struct IdList_item *pNewItem = &pNew->a[i];
 | |
|     struct IdList_item *pOldItem = &p->a[i];
 | |
|     pNewItem->zName = sqlite3DbStrDup(db, pOldItem->zName);
 | |
|     pNewItem->idx = pOldItem->idx;
 | |
|   }
 | |
|   return pNew;
 | |
| }
 | |
| Select *sqlite3SelectDup(sqlite3 *db, Select *p, int flags){
 | |
|   Select *pNew, *pPrior;
 | |
|   assert( db!=0 );
 | |
|   if( p==0 ) return 0;
 | |
|   pNew = sqlite3DbMallocRawNN(db, sizeof(*p) );
 | |
|   if( pNew==0 ) return 0;
 | |
|   pNew->pEList = sqlite3ExprListDup(db, p->pEList, flags);
 | |
|   pNew->pSrc = sqlite3SrcListDup(db, p->pSrc, flags);
 | |
|   pNew->pWhere = sqlite3ExprDup(db, p->pWhere, flags);
 | |
|   pNew->pGroupBy = sqlite3ExprListDup(db, p->pGroupBy, flags);
 | |
|   pNew->pHaving = sqlite3ExprDup(db, p->pHaving, flags);
 | |
|   pNew->pOrderBy = sqlite3ExprListDup(db, p->pOrderBy, flags);
 | |
|   pNew->op = p->op;
 | |
|   pNew->pPrior = pPrior = sqlite3SelectDup(db, p->pPrior, flags);
 | |
|   if( pPrior ) pPrior->pNext = pNew;
 | |
|   pNew->pNext = 0;
 | |
|   pNew->pLimit = sqlite3ExprDup(db, p->pLimit, flags);
 | |
|   pNew->pOffset = sqlite3ExprDup(db, p->pOffset, flags);
 | |
|   pNew->iLimit = 0;
 | |
|   pNew->iOffset = 0;
 | |
|   pNew->selFlags = p->selFlags & ~SF_UsesEphemeral;
 | |
|   pNew->addrOpenEphm[0] = -1;
 | |
|   pNew->addrOpenEphm[1] = -1;
 | |
|   pNew->nSelectRow = p->nSelectRow;
 | |
|   pNew->pWith = withDup(db, p->pWith);
 | |
| #ifdef MAXSCALE
 | |
|   pNew->pInto = sqlite3ExprListDup(db, p->pInto, flags);
 | |
| #endif
 | |
|   sqlite3SelectSetName(pNew, p->zSelName);
 | |
|   return pNew;
 | |
| }
 | |
| #else
 | |
| Select *sqlite3SelectDup(sqlite3 *db, Select *p, int flags){
 | |
|   assert( p==0 );
 | |
|   return 0;
 | |
| }
 | |
| #endif
 | |
| 
 | |
| 
 | |
| /*
 | |
| ** Add a new element to the end of an expression list.  If pList is
 | |
| ** initially NULL, then create a new expression list.
 | |
| **
 | |
| ** If a memory allocation error occurs, the entire list is freed and
 | |
| ** NULL is returned.  If non-NULL is returned, then it is guaranteed
 | |
| ** that the new entry was successfully appended.
 | |
| */
 | |
| ExprList *sqlite3ExprListAppend(
 | |
|   Parse *pParse,          /* Parsing context */
 | |
|   ExprList *pList,        /* List to which to append. Might be NULL */
 | |
|   Expr *pExpr             /* Expression to be appended. Might be NULL */
 | |
| ){
 | |
|   sqlite3 *db = pParse->db;
 | |
|   assert( db!=0 );
 | |
|   if( pList==0 ){
 | |
|     pList = sqlite3DbMallocRawNN(db, sizeof(ExprList) );
 | |
|     if( pList==0 ){
 | |
|       goto no_mem;
 | |
|     }
 | |
|     pList->nExpr = 0;
 | |
|     pList->a = sqlite3DbMallocRawNN(db, sizeof(pList->a[0]));
 | |
|     if( pList->a==0 ) goto no_mem;
 | |
|   }else if( (pList->nExpr & (pList->nExpr-1))==0 ){
 | |
|     struct ExprList_item *a;
 | |
|     assert( pList->nExpr>0 );
 | |
|     a = sqlite3DbRealloc(db, pList->a, pList->nExpr*2*sizeof(pList->a[0]));
 | |
|     if( a==0 ){
 | |
|       goto no_mem;
 | |
|     }
 | |
|     pList->a = a;
 | |
|   }
 | |
|   assert( pList->a!=0 );
 | |
|   if( 1 ){
 | |
|     struct ExprList_item *pItem = &pList->a[pList->nExpr++];
 | |
|     memset(pItem, 0, sizeof(*pItem));
 | |
|     pItem->pExpr = pExpr;
 | |
|   }
 | |
|   return pList;
 | |
| 
 | |
| no_mem:     
 | |
|   /* Avoid leaking memory if malloc has failed. */
 | |
|   sqlite3ExprDelete(db, pExpr);
 | |
|   sqlite3ExprListDelete(db, pList);
 | |
|   return 0;
 | |
| }
 | |
| 
 | |
| #ifdef MAXSCALE
 | |
| /*
 | |
| ** Add an expression list to the end of an expression list. If pList
 | |
| ** is initially NULL, then create a new expression list.
 | |
| **
 | |
| ** If a memory allocation error occurs, the entire list is freed and
 | |
| ** NULL is returned.  If non-NULL is returned, then it is guaranteed
 | |
| ** that the list was successfully appended.
 | |
| */
 | |
| ExprList *sqlite3ExprListAppendList(
 | |
|   Parse *pParse,          /* Parsing context */
 | |
|   ExprList *pList,        /* List to which to append. Might be NULL */
 | |
|   ExprList *pAppend       /* List to be appended. Might be NULL */
 | |
| ){
 | |
|   sqlite3 *db = pParse->db;
 | |
|   int i;
 | |
|   assert( db!=0 );
 | |
|   if (!pAppend) {
 | |
|     return pList;
 | |
|   }
 | |
|   if (!pList) {
 | |
|     return pAppend;
 | |
|   }
 | |
| 
 | |
|   for (i = 0; i < pAppend->nExpr; ++i) {
 | |
|     pList = sqlite3ExprListAppend(pParse, pList, pAppend->a[i].pExpr);
 | |
|     if (pList) {
 | |
|       pAppend->a[i].pExpr = NULL;
 | |
|     }
 | |
|     else {
 | |
|       goto no_mem;
 | |
|     }
 | |
|   }
 | |
|   sqlite3ExprListDelete(db, pAppend);
 | |
|   return pList;
 | |
| 
 | |
| no_mem:
 | |
|   sqlite3ExprListDelete(db, pList);
 | |
|   sqlite3ExprListDelete(db, pAppend);
 | |
|   return 0;
 | |
| }
 | |
| 
 | |
| #endif
 | |
| /*
 | |
| ** Set the sort order for the last element on the given ExprList.
 | |
| */
 | |
| void sqlite3ExprListSetSortOrder(ExprList *p, int iSortOrder){
 | |
|   if( p==0 ) return;
 | |
|   assert( SQLITE_SO_UNDEFINED<0 && SQLITE_SO_ASC>=0 && SQLITE_SO_DESC>0 );
 | |
|   assert( p->nExpr>0 );
 | |
|   if( iSortOrder<0 ){
 | |
|     assert( p->a[p->nExpr-1].sortOrder==SQLITE_SO_ASC );
 | |
|     return;
 | |
|   }
 | |
|   p->a[p->nExpr-1].sortOrder = (u8)iSortOrder;
 | |
| }
 | |
| 
 | |
| /*
 | |
| ** Set the ExprList.a[].zName element of the most recently added item
 | |
| ** on the expression list.
 | |
| **
 | |
| ** pList might be NULL following an OOM error.  But pName should never be
 | |
| ** NULL.  If a memory allocation fails, the pParse->db->mallocFailed flag
 | |
| ** is set.
 | |
| */
 | |
| void sqlite3ExprListSetName(
 | |
|   Parse *pParse,          /* Parsing context */
 | |
|   ExprList *pList,        /* List to which to add the span. */
 | |
|   Token *pName,           /* Name to be added */
 | |
|   int dequote             /* True to cause the name to be dequoted */
 | |
| ){
 | |
|   assert( pList!=0 || pParse->db->mallocFailed!=0 );
 | |
|   if( pList ){
 | |
|     struct ExprList_item *pItem;
 | |
|     assert( pList->nExpr>0 );
 | |
|     pItem = &pList->a[pList->nExpr-1];
 | |
|     assert( pItem->zName==0 );
 | |
|     pItem->zName = sqlite3DbStrNDup(pParse->db, pName->z, pName->n);
 | |
|     if( dequote && pItem->zName ) sqlite3Dequote(pItem->zName);
 | |
|   }
 | |
| }
 | |
| 
 | |
| /*
 | |
| ** Set the ExprList.a[].zSpan element of the most recently added item
 | |
| ** on the expression list.
 | |
| **
 | |
| ** pList might be NULL following an OOM error.  But pSpan should never be
 | |
| ** NULL.  If a memory allocation fails, the pParse->db->mallocFailed flag
 | |
| ** is set.
 | |
| */
 | |
| void sqlite3ExprListSetSpan(
 | |
|   Parse *pParse,          /* Parsing context */
 | |
|   ExprList *pList,        /* List to which to add the span. */
 | |
|   ExprSpan *pSpan         /* The span to be added */
 | |
| ){
 | |
|   sqlite3 *db = pParse->db;
 | |
|   assert( pList!=0 || db->mallocFailed!=0 );
 | |
|   if( pList ){
 | |
|     struct ExprList_item *pItem = &pList->a[pList->nExpr-1];
 | |
|     assert( pList->nExpr>0 );
 | |
|     assert( db->mallocFailed || pItem->pExpr==pSpan->pExpr );
 | |
|     sqlite3DbFree(db, pItem->zSpan);
 | |
|     pItem->zSpan = sqlite3DbStrNDup(db, (char*)pSpan->zStart,
 | |
|                                     (int)(pSpan->zEnd - pSpan->zStart));
 | |
|   }
 | |
| }
 | |
| 
 | |
| /*
 | |
| ** If the expression list pEList contains more than iLimit elements,
 | |
| ** leave an error message in pParse.
 | |
| */
 | |
| void sqlite3ExprListCheckLength(
 | |
|   Parse *pParse,
 | |
|   ExprList *pEList,
 | |
|   const char *zObject
 | |
| ){
 | |
|   int mx = pParse->db->aLimit[SQLITE_LIMIT_COLUMN];
 | |
|   testcase( pEList && pEList->nExpr==mx );
 | |
|   testcase( pEList && pEList->nExpr==mx+1 );
 | |
|   if( pEList && pEList->nExpr>mx ){
 | |
|     sqlite3ErrorMsg(pParse, "too many columns in %s", zObject);
 | |
|   }
 | |
| }
 | |
| 
 | |
| /*
 | |
| ** Delete an entire expression list.
 | |
| */
 | |
| void sqlite3ExprListDelete(sqlite3 *db, ExprList *pList){
 | |
|   int i;
 | |
|   struct ExprList_item *pItem;
 | |
|   if( pList==0 ) return;
 | |
|   assert( pList->a!=0 || pList->nExpr==0 );
 | |
|   for(pItem=pList->a, i=0; i<pList->nExpr; i++, pItem++){
 | |
|     sqlite3ExprDelete(db, pItem->pExpr);
 | |
|     sqlite3DbFree(db, pItem->zName);
 | |
|     sqlite3DbFree(db, pItem->zSpan);
 | |
|   }
 | |
|   sqlite3DbFree(db, pList->a);
 | |
|   sqlite3DbFree(db, pList);
 | |
| }
 | |
| 
 | |
| /*
 | |
| ** Return the bitwise-OR of all Expr.flags fields in the given
 | |
| ** ExprList.
 | |
| */
 | |
| u32 sqlite3ExprListFlags(const ExprList *pList){
 | |
|   int i;
 | |
|   u32 m = 0;
 | |
|   if( pList ){
 | |
|     for(i=0; i<pList->nExpr; i++){
 | |
|        Expr *pExpr = pList->a[i].pExpr;
 | |
|        if( ALWAYS(pExpr) ) m |= pExpr->flags;
 | |
|     }
 | |
|   }
 | |
|   return m;
 | |
| }
 | |
| 
 | |
| /*
 | |
| ** These routines are Walker callbacks used to check expressions to
 | |
| ** see if they are "constant" for some definition of constant.  The
 | |
| ** Walker.eCode value determines the type of "constant" we are looking
 | |
| ** for.
 | |
| **
 | |
| ** These callback routines are used to implement the following:
 | |
| **
 | |
| **     sqlite3ExprIsConstant()                  pWalker->eCode==1
 | |
| **     sqlite3ExprIsConstantNotJoin()           pWalker->eCode==2
 | |
| **     sqlite3ExprIsTableConstant()             pWalker->eCode==3
 | |
| **     sqlite3ExprIsConstantOrFunction()        pWalker->eCode==4 or 5
 | |
| **
 | |
| ** In all cases, the callbacks set Walker.eCode=0 and abort if the expression
 | |
| ** is found to not be a constant.
 | |
| **
 | |
| ** The sqlite3ExprIsConstantOrFunction() is used for evaluating expressions
 | |
| ** in a CREATE TABLE statement.  The Walker.eCode value is 5 when parsing
 | |
| ** an existing schema and 4 when processing a new statement.  A bound
 | |
| ** parameter raises an error for new statements, but is silently converted
 | |
| ** to NULL for existing schemas.  This allows sqlite_master tables that 
 | |
| ** contain a bound parameter because they were generated by older versions
 | |
| ** of SQLite to be parsed by newer versions of SQLite without raising a
 | |
| ** malformed schema error.
 | |
| */
 | |
| static int exprNodeIsConstant(Walker *pWalker, Expr *pExpr){
 | |
| 
 | |
|   /* If pWalker->eCode is 2 then any term of the expression that comes from
 | |
|   ** the ON or USING clauses of a left join disqualifies the expression
 | |
|   ** from being considered constant. */
 | |
|   if( pWalker->eCode==2 && ExprHasProperty(pExpr, EP_FromJoin) ){
 | |
|     pWalker->eCode = 0;
 | |
|     return WRC_Abort;
 | |
|   }
 | |
| 
 | |
|   switch( pExpr->op ){
 | |
|     /* Consider functions to be constant if all their arguments are constant
 | |
|     ** and either pWalker->eCode==4 or 5 or the function has the
 | |
|     ** SQLITE_FUNC_CONST flag. */
 | |
|     case TK_FUNCTION:
 | |
|       if( pWalker->eCode>=4 || ExprHasProperty(pExpr,EP_ConstFunc) ){
 | |
|         return WRC_Continue;
 | |
|       }else{
 | |
|         pWalker->eCode = 0;
 | |
|         return WRC_Abort;
 | |
|       }
 | |
|     case TK_ID:
 | |
|     case TK_COLUMN:
 | |
|     case TK_AGG_FUNCTION:
 | |
|     case TK_AGG_COLUMN:
 | |
|       testcase( pExpr->op==TK_ID );
 | |
|       testcase( pExpr->op==TK_COLUMN );
 | |
|       testcase( pExpr->op==TK_AGG_FUNCTION );
 | |
|       testcase( pExpr->op==TK_AGG_COLUMN );
 | |
|       if( pWalker->eCode==3 && pExpr->iTable==pWalker->u.iCur ){
 | |
|         return WRC_Continue;
 | |
|       }else{
 | |
|         pWalker->eCode = 0;
 | |
|         return WRC_Abort;
 | |
|       }
 | |
|     case TK_VARIABLE:
 | |
|       if( pWalker->eCode==5 ){
 | |
|         /* Silently convert bound parameters that appear inside of CREATE
 | |
|         ** statements into a NULL when parsing the CREATE statement text out
 | |
|         ** of the sqlite_master table */
 | |
|         pExpr->op = TK_NULL;
 | |
|       }else if( pWalker->eCode==4 ){
 | |
|         /* A bound parameter in a CREATE statement that originates from
 | |
|         ** sqlite3_prepare() causes an error */
 | |
|         pWalker->eCode = 0;
 | |
|         return WRC_Abort;
 | |
|       }
 | |
|       /* Fall through */
 | |
|     default:
 | |
|       testcase( pExpr->op==TK_SELECT ); /* selectNodeIsConstant will disallow */
 | |
|       testcase( pExpr->op==TK_EXISTS ); /* selectNodeIsConstant will disallow */
 | |
|       return WRC_Continue;
 | |
|   }
 | |
| }
 | |
| static int selectNodeIsConstant(Walker *pWalker, Select *NotUsed){
 | |
|   UNUSED_PARAMETER(NotUsed);
 | |
|   pWalker->eCode = 0;
 | |
|   return WRC_Abort;
 | |
| }
 | |
| static int exprIsConst(Expr *p, int initFlag, int iCur){
 | |
|   Walker w;
 | |
|   memset(&w, 0, sizeof(w));
 | |
|   w.eCode = initFlag;
 | |
|   w.xExprCallback = exprNodeIsConstant;
 | |
|   w.xSelectCallback = selectNodeIsConstant;
 | |
|   w.u.iCur = iCur;
 | |
|   sqlite3WalkExpr(&w, p);
 | |
|   return w.eCode;
 | |
| }
 | |
| 
 | |
| /*
 | |
| ** Walk an expression tree.  Return non-zero if the expression is constant
 | |
| ** and 0 if it involves variables or function calls.
 | |
| **
 | |
| ** For the purposes of this function, a double-quoted string (ex: "abc")
 | |
| ** is considered a variable but a single-quoted string (ex: 'abc') is
 | |
| ** a constant.
 | |
| */
 | |
| int sqlite3ExprIsConstant(Expr *p){
 | |
|   return exprIsConst(p, 1, 0);
 | |
| }
 | |
| 
 | |
| /*
 | |
| ** Walk an expression tree.  Return non-zero if the expression is constant
 | |
| ** that does no originate from the ON or USING clauses of a join.
 | |
| ** Return 0 if it involves variables or function calls or terms from
 | |
| ** an ON or USING clause.
 | |
| */
 | |
| int sqlite3ExprIsConstantNotJoin(Expr *p){
 | |
|   return exprIsConst(p, 2, 0);
 | |
| }
 | |
| 
 | |
| /*
 | |
| ** Walk an expression tree.  Return non-zero if the expression is constant
 | |
| ** for any single row of the table with cursor iCur.  In other words, the
 | |
| ** expression must not refer to any non-deterministic function nor any
 | |
| ** table other than iCur.
 | |
| */
 | |
| int sqlite3ExprIsTableConstant(Expr *p, int iCur){
 | |
|   return exprIsConst(p, 3, iCur);
 | |
| }
 | |
| 
 | |
| /*
 | |
| ** Walk an expression tree.  Return non-zero if the expression is constant
 | |
| ** or a function call with constant arguments.  Return and 0 if there
 | |
| ** are any variables.
 | |
| **
 | |
| ** For the purposes of this function, a double-quoted string (ex: "abc")
 | |
| ** is considered a variable but a single-quoted string (ex: 'abc') is
 | |
| ** a constant.
 | |
| */
 | |
| int sqlite3ExprIsConstantOrFunction(Expr *p, u8 isInit){
 | |
|   assert( isInit==0 || isInit==1 );
 | |
|   return exprIsConst(p, 4+isInit, 0);
 | |
| }
 | |
| 
 | |
| #ifdef SQLITE_ENABLE_CURSOR_HINTS
 | |
| /*
 | |
| ** Walk an expression tree.  Return 1 if the expression contains a
 | |
| ** subquery of some kind.  Return 0 if there are no subqueries.
 | |
| */
 | |
| int sqlite3ExprContainsSubquery(Expr *p){
 | |
|   Walker w;
 | |
|   memset(&w, 0, sizeof(w));
 | |
|   w.eCode = 1;
 | |
|   w.xExprCallback = sqlite3ExprWalkNoop;
 | |
|   w.xSelectCallback = selectNodeIsConstant;
 | |
|   sqlite3WalkExpr(&w, p);
 | |
|   return w.eCode==0;
 | |
| }
 | |
| #endif
 | |
| 
 | |
| /*
 | |
| ** If the expression p codes a constant integer that is small enough
 | |
| ** to fit in a 32-bit integer, return 1 and put the value of the integer
 | |
| ** in *pValue.  If the expression is not an integer or if it is too big
 | |
| ** to fit in a signed 32-bit integer, return 0 and leave *pValue unchanged.
 | |
| */
 | |
| int sqlite3ExprIsInteger(Expr *p, int *pValue){
 | |
|   int rc = 0;
 | |
| 
 | |
|   /* If an expression is an integer literal that fits in a signed 32-bit
 | |
|   ** integer, then the EP_IntValue flag will have already been set */
 | |
|   assert( p->op!=TK_INTEGER || (p->flags & EP_IntValue)!=0
 | |
|            || sqlite3GetInt32(p->u.zToken, &rc)==0 );
 | |
| 
 | |
|   if( p->flags & EP_IntValue ){
 | |
|     *pValue = p->u.iValue;
 | |
|     return 1;
 | |
|   }
 | |
|   switch( p->op ){
 | |
|     case TK_UPLUS: {
 | |
|       rc = sqlite3ExprIsInteger(p->pLeft, pValue);
 | |
|       break;
 | |
|     }
 | |
|     case TK_UMINUS: {
 | |
|       int v;
 | |
|       if( sqlite3ExprIsInteger(p->pLeft, &v) ){
 | |
|         assert( v!=(-2147483647-1) );
 | |
|         *pValue = -v;
 | |
|         rc = 1;
 | |
|       }
 | |
|       break;
 | |
|     }
 | |
|     default: break;
 | |
|   }
 | |
|   return rc;
 | |
| }
 | |
| 
 | |
| /*
 | |
| ** Return FALSE if there is no chance that the expression can be NULL.
 | |
| **
 | |
| ** If the expression might be NULL or if the expression is too complex
 | |
| ** to tell return TRUE.  
 | |
| **
 | |
| ** This routine is used as an optimization, to skip OP_IsNull opcodes
 | |
| ** when we know that a value cannot be NULL.  Hence, a false positive
 | |
| ** (returning TRUE when in fact the expression can never be NULL) might
 | |
| ** be a small performance hit but is otherwise harmless.  On the other
 | |
| ** hand, a false negative (returning FALSE when the result could be NULL)
 | |
| ** will likely result in an incorrect answer.  So when in doubt, return
 | |
| ** TRUE.
 | |
| */
 | |
| int sqlite3ExprCanBeNull(const Expr *p){
 | |
|   u8 op;
 | |
|   while( p->op==TK_UPLUS || p->op==TK_UMINUS ){ p = p->pLeft; }
 | |
|   op = p->op;
 | |
|   if( op==TK_REGISTER ) op = p->op2;
 | |
|   switch( op ){
 | |
|     case TK_INTEGER:
 | |
|     case TK_STRING:
 | |
|     case TK_FLOAT:
 | |
|     case TK_BLOB:
 | |
|       return 0;
 | |
|     case TK_COLUMN:
 | |
|       assert( p->pTab!=0 );
 | |
|       return ExprHasProperty(p, EP_CanBeNull) ||
 | |
|              (p->iColumn>=0 && p->pTab->aCol[p->iColumn].notNull==0);
 | |
|     default:
 | |
|       return 1;
 | |
|   }
 | |
| }
 | |
| 
 | |
| /*
 | |
| ** Return TRUE if the given expression is a constant which would be
 | |
| ** unchanged by OP_Affinity with the affinity given in the second
 | |
| ** argument.
 | |
| **
 | |
| ** This routine is used to determine if the OP_Affinity operation
 | |
| ** can be omitted.  When in doubt return FALSE.  A false negative
 | |
| ** is harmless.  A false positive, however, can result in the wrong
 | |
| ** answer.
 | |
| */
 | |
| int sqlite3ExprNeedsNoAffinityChange(const Expr *p, char aff){
 | |
|   u8 op;
 | |
|   if( aff==SQLITE_AFF_BLOB ) return 1;
 | |
|   while( p->op==TK_UPLUS || p->op==TK_UMINUS ){ p = p->pLeft; }
 | |
|   op = p->op;
 | |
|   if( op==TK_REGISTER ) op = p->op2;
 | |
|   switch( op ){
 | |
|     case TK_INTEGER: {
 | |
|       return aff==SQLITE_AFF_INTEGER || aff==SQLITE_AFF_NUMERIC;
 | |
|     }
 | |
|     case TK_FLOAT: {
 | |
|       return aff==SQLITE_AFF_REAL || aff==SQLITE_AFF_NUMERIC;
 | |
|     }
 | |
|     case TK_STRING: {
 | |
|       return aff==SQLITE_AFF_TEXT;
 | |
|     }
 | |
|     case TK_BLOB: {
 | |
|       return 1;
 | |
|     }
 | |
|     case TK_COLUMN: {
 | |
|       assert( p->iTable>=0 );  /* p cannot be part of a CHECK constraint */
 | |
|       return p->iColumn<0
 | |
|           && (aff==SQLITE_AFF_INTEGER || aff==SQLITE_AFF_NUMERIC);
 | |
|     }
 | |
|     default: {
 | |
|       return 0;
 | |
|     }
 | |
|   }
 | |
| }
 | |
| 
 | |
| /*
 | |
| ** Return TRUE if the given string is a row-id column name.
 | |
| */
 | |
| int sqlite3IsRowid(const char *z){
 | |
|   if( sqlite3StrICmp(z, "_ROWID_")==0 ) return 1;
 | |
|   if( sqlite3StrICmp(z, "ROWID")==0 ) return 1;
 | |
|   if( sqlite3StrICmp(z, "OID")==0 ) return 1;
 | |
|   return 0;
 | |
| }
 | |
| 
 | |
| /*
 | |
| ** Return true if we are able to the IN operator optimization on a
 | |
| ** query of the form
 | |
| **
 | |
| **       x IN (SELECT ...)
 | |
| **
 | |
| ** Where the SELECT... clause is as specified by the parameter to this
 | |
| ** routine.
 | |
| **
 | |
| ** The Select object passed in has already been preprocessed and no
 | |
| ** errors have been found.
 | |
| */
 | |
| #ifndef SQLITE_OMIT_SUBQUERY
 | |
| static int isCandidateForInOpt(Select *p){
 | |
|   SrcList *pSrc;
 | |
|   ExprList *pEList;
 | |
|   Table *pTab;
 | |
|   if( p==0 ) return 0;                   /* right-hand side of IN is SELECT */
 | |
|   if( p->pPrior ) return 0;              /* Not a compound SELECT */
 | |
|   if( p->selFlags & (SF_Distinct|SF_Aggregate) ){
 | |
|     testcase( (p->selFlags & (SF_Distinct|SF_Aggregate))==SF_Distinct );
 | |
|     testcase( (p->selFlags & (SF_Distinct|SF_Aggregate))==SF_Aggregate );
 | |
|     return 0; /* No DISTINCT keyword and no aggregate functions */
 | |
|   }
 | |
|   assert( p->pGroupBy==0 );              /* Has no GROUP BY clause */
 | |
|   if( p->pLimit ) return 0;              /* Has no LIMIT clause */
 | |
|   assert( p->pOffset==0 );               /* No LIMIT means no OFFSET */
 | |
|   if( p->pWhere ) return 0;              /* Has no WHERE clause */
 | |
|   pSrc = p->pSrc;
 | |
|   assert( pSrc!=0 );
 | |
|   if( pSrc->nSrc!=1 ) return 0;          /* Single term in FROM clause */
 | |
|   if( pSrc->a[0].pSelect ) return 0;     /* FROM is not a subquery or view */
 | |
|   pTab = pSrc->a[0].pTab;
 | |
|   if( NEVER(pTab==0) ) return 0;
 | |
|   assert( pTab->pSelect==0 );            /* FROM clause is not a view */
 | |
|   if( IsVirtual(pTab) ) return 0;        /* FROM clause not a virtual table */
 | |
|   pEList = p->pEList;
 | |
|   if( pEList->nExpr!=1 ) return 0;       /* One column in the result set */
 | |
|   if( pEList->a[0].pExpr->op!=TK_COLUMN ) return 0; /* Result is a column */
 | |
|   return 1;
 | |
| }
 | |
| #endif /* SQLITE_OMIT_SUBQUERY */
 | |
| 
 | |
| /*
 | |
| ** Code an OP_Once instruction and allocate space for its flag. Return the 
 | |
| ** address of the new instruction.
 | |
| */
 | |
| int sqlite3CodeOnce(Parse *pParse){
 | |
|   Vdbe *v = sqlite3GetVdbe(pParse);      /* Virtual machine being coded */
 | |
|   return sqlite3VdbeAddOp1(v, OP_Once, pParse->nOnce++);
 | |
| }
 | |
| 
 | |
| /*
 | |
| ** Generate code that checks the left-most column of index table iCur to see if
 | |
| ** it contains any NULL entries.  Cause the register at regHasNull to be set
 | |
| ** to a non-NULL value if iCur contains no NULLs.  Cause register regHasNull
 | |
| ** to be set to NULL if iCur contains one or more NULL values.
 | |
| */
 | |
| static void sqlite3SetHasNullFlag(Vdbe *v, int iCur, int regHasNull){
 | |
|   int addr1;
 | |
|   sqlite3VdbeAddOp2(v, OP_Integer, 0, regHasNull);
 | |
|   addr1 = sqlite3VdbeAddOp1(v, OP_Rewind, iCur); VdbeCoverage(v);
 | |
|   sqlite3VdbeAddOp3(v, OP_Column, iCur, 0, regHasNull);
 | |
|   sqlite3VdbeChangeP5(v, OPFLAG_TYPEOFARG);
 | |
|   VdbeComment((v, "first_entry_in(%d)", iCur));
 | |
|   sqlite3VdbeJumpHere(v, addr1);
 | |
| }
 | |
| 
 | |
| 
 | |
| #ifndef SQLITE_OMIT_SUBQUERY
 | |
| /*
 | |
| ** The argument is an IN operator with a list (not a subquery) on the 
 | |
| ** right-hand side.  Return TRUE if that list is constant.
 | |
| */
 | |
| static int sqlite3InRhsIsConstant(Expr *pIn){
 | |
|   Expr *pLHS;
 | |
|   int res;
 | |
|   assert( !ExprHasProperty(pIn, EP_xIsSelect) );
 | |
|   pLHS = pIn->pLeft;
 | |
|   pIn->pLeft = 0;
 | |
|   res = sqlite3ExprIsConstant(pIn);
 | |
|   pIn->pLeft = pLHS;
 | |
|   return res;
 | |
| }
 | |
| #endif
 | |
| 
 | |
| /*
 | |
| ** This function is used by the implementation of the IN (...) operator.
 | |
| ** The pX parameter is the expression on the RHS of the IN operator, which
 | |
| ** might be either a list of expressions or a subquery.
 | |
| **
 | |
| ** The job of this routine is to find or create a b-tree object that can
 | |
| ** be used either to test for membership in the RHS set or to iterate through
 | |
| ** all members of the RHS set, skipping duplicates.
 | |
| **
 | |
| ** A cursor is opened on the b-tree object that is the RHS of the IN operator
 | |
| ** and pX->iTable is set to the index of that cursor.
 | |
| **
 | |
| ** The returned value of this function indicates the b-tree type, as follows:
 | |
| **
 | |
| **   IN_INDEX_ROWID      - The cursor was opened on a database table.
 | |
| **   IN_INDEX_INDEX_ASC  - The cursor was opened on an ascending index.
 | |
| **   IN_INDEX_INDEX_DESC - The cursor was opened on a descending index.
 | |
| **   IN_INDEX_EPH        - The cursor was opened on a specially created and
 | |
| **                         populated epheremal table.
 | |
| **   IN_INDEX_NOOP       - No cursor was allocated.  The IN operator must be
 | |
| **                         implemented as a sequence of comparisons.
 | |
| **
 | |
| ** An existing b-tree might be used if the RHS expression pX is a simple
 | |
| ** subquery such as:
 | |
| **
 | |
| **     SELECT <column> FROM <table>
 | |
| **
 | |
| ** If the RHS of the IN operator is a list or a more complex subquery, then
 | |
| ** an ephemeral table might need to be generated from the RHS and then
 | |
| ** pX->iTable made to point to the ephemeral table instead of an
 | |
| ** existing table.
 | |
| **
 | |
| ** The inFlags parameter must contain exactly one of the bits
 | |
| ** IN_INDEX_MEMBERSHIP or IN_INDEX_LOOP.  If inFlags contains
 | |
| ** IN_INDEX_MEMBERSHIP, then the generated table will be used for a
 | |
| ** fast membership test.  When the IN_INDEX_LOOP bit is set, the
 | |
| ** IN index will be used to loop over all values of the RHS of the
 | |
| ** IN operator.
 | |
| **
 | |
| ** When IN_INDEX_LOOP is used (and the b-tree will be used to iterate
 | |
| ** through the set members) then the b-tree must not contain duplicates.
 | |
| ** An epheremal table must be used unless the selected <column> is guaranteed
 | |
| ** to be unique - either because it is an INTEGER PRIMARY KEY or it
 | |
| ** has a UNIQUE constraint or UNIQUE index.
 | |
| **
 | |
| ** When IN_INDEX_MEMBERSHIP is used (and the b-tree will be used 
 | |
| ** for fast set membership tests) then an epheremal table must 
 | |
| ** be used unless <column> is an INTEGER PRIMARY KEY or an index can 
 | |
| ** be found with <column> as its left-most column.
 | |
| **
 | |
| ** If the IN_INDEX_NOOP_OK and IN_INDEX_MEMBERSHIP are both set and
 | |
| ** if the RHS of the IN operator is a list (not a subquery) then this
 | |
| ** routine might decide that creating an ephemeral b-tree for membership
 | |
| ** testing is too expensive and return IN_INDEX_NOOP.  In that case, the
 | |
| ** calling routine should implement the IN operator using a sequence
 | |
| ** of Eq or Ne comparison operations.
 | |
| **
 | |
| ** When the b-tree is being used for membership tests, the calling function
 | |
| ** might need to know whether or not the RHS side of the IN operator
 | |
| ** contains a NULL.  If prRhsHasNull is not a NULL pointer and 
 | |
| ** if there is any chance that the (...) might contain a NULL value at
 | |
| ** runtime, then a register is allocated and the register number written
 | |
| ** to *prRhsHasNull. If there is no chance that the (...) contains a
 | |
| ** NULL value, then *prRhsHasNull is left unchanged.
 | |
| **
 | |
| ** If a register is allocated and its location stored in *prRhsHasNull, then
 | |
| ** the value in that register will be NULL if the b-tree contains one or more
 | |
| ** NULL values, and it will be some non-NULL value if the b-tree contains no
 | |
| ** NULL values.
 | |
| */
 | |
| #ifndef SQLITE_OMIT_SUBQUERY
 | |
| int sqlite3FindInIndex(Parse *pParse, Expr *pX, u32 inFlags, int *prRhsHasNull){
 | |
|   Select *p;                            /* SELECT to the right of IN operator */
 | |
|   int eType = 0;                        /* Type of RHS table. IN_INDEX_* */
 | |
|   int iTab = pParse->nTab++;            /* Cursor of the RHS table */
 | |
|   int mustBeUnique;                     /* True if RHS must be unique */
 | |
|   Vdbe *v = sqlite3GetVdbe(pParse);     /* Virtual machine being coded */
 | |
| 
 | |
|   assert( pX->op==TK_IN );
 | |
|   mustBeUnique = (inFlags & IN_INDEX_LOOP)!=0;
 | |
| 
 | |
|   /* Check to see if an existing table or index can be used to
 | |
|   ** satisfy the query.  This is preferable to generating a new 
 | |
|   ** ephemeral table.
 | |
|   */
 | |
|   p = (ExprHasProperty(pX, EP_xIsSelect) ? pX->x.pSelect : 0);
 | |
|   if( pParse->nErr==0 && isCandidateForInOpt(p) ){
 | |
|     sqlite3 *db = pParse->db;              /* Database connection */
 | |
|     Table *pTab;                           /* Table <table>. */
 | |
|     Expr *pExpr;                           /* Expression <column> */
 | |
|     i16 iCol;                              /* Index of column <column> */
 | |
|     i16 iDb;                               /* Database idx for pTab */
 | |
| 
 | |
|     assert( p );                        /* Because of isCandidateForInOpt(p) */
 | |
|     assert( p->pEList!=0 );             /* Because of isCandidateForInOpt(p) */
 | |
|     assert( p->pEList->a[0].pExpr!=0 ); /* Because of isCandidateForInOpt(p) */
 | |
|     assert( p->pSrc!=0 );               /* Because of isCandidateForInOpt(p) */
 | |
|     pTab = p->pSrc->a[0].pTab;
 | |
|     pExpr = p->pEList->a[0].pExpr;
 | |
|     iCol = (i16)pExpr->iColumn;
 | |
|    
 | |
|     /* Code an OP_Transaction and OP_TableLock for <table>. */
 | |
|     iDb = sqlite3SchemaToIndex(db, pTab->pSchema);
 | |
|     sqlite3CodeVerifySchema(pParse, iDb);
 | |
|     sqlite3TableLock(pParse, iDb, pTab->tnum, 0, pTab->zName);
 | |
| 
 | |
|     /* This function is only called from two places. In both cases the vdbe
 | |
|     ** has already been allocated. So assume sqlite3GetVdbe() is always
 | |
|     ** successful here.
 | |
|     */
 | |
|     assert(v);
 | |
|     if( iCol<0 ){
 | |
|       int iAddr = sqlite3CodeOnce(pParse);
 | |
|       VdbeCoverage(v);
 | |
| 
 | |
|       sqlite3OpenTable(pParse, iTab, iDb, pTab, OP_OpenRead);
 | |
|       eType = IN_INDEX_ROWID;
 | |
| 
 | |
|       sqlite3VdbeJumpHere(v, iAddr);
 | |
|     }else{
 | |
|       Index *pIdx;                         /* Iterator variable */
 | |
| 
 | |
|       /* The collation sequence used by the comparison. If an index is to
 | |
|       ** be used in place of a temp-table, it must be ordered according
 | |
|       ** to this collation sequence.  */
 | |
|       CollSeq *pReq = sqlite3BinaryCompareCollSeq(pParse, pX->pLeft, pExpr);
 | |
| 
 | |
|       /* Check that the affinity that will be used to perform the 
 | |
|       ** comparison is the same as the affinity of the column. If
 | |
|       ** it is not, it is not possible to use any index.
 | |
|       */
 | |
|       int affinity_ok = sqlite3IndexAffinityOk(pX, pTab->aCol[iCol].affinity);
 | |
| 
 | |
|       for(pIdx=pTab->pIndex; pIdx && eType==0 && affinity_ok; pIdx=pIdx->pNext){
 | |
|         if( (pIdx->aiColumn[0]==iCol)
 | |
|          && sqlite3FindCollSeq(db, ENC(db), pIdx->azColl[0], 0)==pReq
 | |
|          && (!mustBeUnique || (pIdx->nKeyCol==1 && IsUniqueIndex(pIdx)))
 | |
|         ){
 | |
|           int iAddr = sqlite3CodeOnce(pParse); VdbeCoverage(v);
 | |
|           sqlite3VdbeAddOp3(v, OP_OpenRead, iTab, pIdx->tnum, iDb);
 | |
|           sqlite3VdbeSetP4KeyInfo(pParse, pIdx);
 | |
|           VdbeComment((v, "%s", pIdx->zName));
 | |
|           assert( IN_INDEX_INDEX_DESC == IN_INDEX_INDEX_ASC+1 );
 | |
|           eType = IN_INDEX_INDEX_ASC + pIdx->aSortOrder[0];
 | |
| 
 | |
|           if( prRhsHasNull && !pTab->aCol[iCol].notNull ){
 | |
|             *prRhsHasNull = ++pParse->nMem;
 | |
|             sqlite3SetHasNullFlag(v, iTab, *prRhsHasNull);
 | |
|           }
 | |
|           sqlite3VdbeJumpHere(v, iAddr);
 | |
|         }
 | |
|       }
 | |
|     }
 | |
|   }
 | |
| 
 | |
|   /* If no preexisting index is available for the IN clause
 | |
|   ** and IN_INDEX_NOOP is an allowed reply
 | |
|   ** and the RHS of the IN operator is a list, not a subquery
 | |
|   ** and the RHS is not contant or has two or fewer terms,
 | |
|   ** then it is not worth creating an ephemeral table to evaluate
 | |
|   ** the IN operator so return IN_INDEX_NOOP.
 | |
|   */
 | |
|   if( eType==0
 | |
|    && (inFlags & IN_INDEX_NOOP_OK)
 | |
|    && !ExprHasProperty(pX, EP_xIsSelect)
 | |
|    && (!sqlite3InRhsIsConstant(pX) || pX->x.pList->nExpr<=2)
 | |
|   ){
 | |
|     eType = IN_INDEX_NOOP;
 | |
|   }
 | |
|      
 | |
| 
 | |
|   if( eType==0 ){
 | |
|     /* Could not find an existing table or index to use as the RHS b-tree.
 | |
|     ** We will have to generate an ephemeral table to do the job.
 | |
|     */
 | |
|     u32 savedNQueryLoop = pParse->nQueryLoop;
 | |
|     int rMayHaveNull = 0;
 | |
|     eType = IN_INDEX_EPH;
 | |
|     if( inFlags & IN_INDEX_LOOP ){
 | |
|       pParse->nQueryLoop = 0;
 | |
|       if( pX->pLeft->iColumn<0 && !ExprHasProperty(pX, EP_xIsSelect) ){
 | |
|         eType = IN_INDEX_ROWID;
 | |
|       }
 | |
|     }else if( prRhsHasNull ){
 | |
|       *prRhsHasNull = rMayHaveNull = ++pParse->nMem;
 | |
|     }
 | |
|     sqlite3CodeSubselect(pParse, pX, rMayHaveNull, eType==IN_INDEX_ROWID);
 | |
|     pParse->nQueryLoop = savedNQueryLoop;
 | |
|   }else{
 | |
|     pX->iTable = iTab;
 | |
|   }
 | |
|   return eType;
 | |
| }
 | |
| #endif
 | |
| 
 | |
| /*
 | |
| ** Generate code for scalar subqueries used as a subquery expression, EXISTS,
 | |
| ** or IN operators.  Examples:
 | |
| **
 | |
| **     (SELECT a FROM b)          -- subquery
 | |
| **     EXISTS (SELECT a FROM b)   -- EXISTS subquery
 | |
| **     x IN (4,5,11)              -- IN operator with list on right-hand side
 | |
| **     x IN (SELECT a FROM b)     -- IN operator with subquery on the right
 | |
| **
 | |
| ** The pExpr parameter describes the expression that contains the IN
 | |
| ** operator or subquery.
 | |
| **
 | |
| ** If parameter isRowid is non-zero, then expression pExpr is guaranteed
 | |
| ** to be of the form "<rowid> IN (?, ?, ?)", where <rowid> is a reference
 | |
| ** to some integer key column of a table B-Tree. In this case, use an
 | |
| ** intkey B-Tree to store the set of IN(...) values instead of the usual
 | |
| ** (slower) variable length keys B-Tree.
 | |
| **
 | |
| ** If rMayHaveNull is non-zero, that means that the operation is an IN
 | |
| ** (not a SELECT or EXISTS) and that the RHS might contains NULLs.
 | |
| ** All this routine does is initialize the register given by rMayHaveNull
 | |
| ** to NULL.  Calling routines will take care of changing this register
 | |
| ** value to non-NULL if the RHS is NULL-free.
 | |
| **
 | |
| ** For a SELECT or EXISTS operator, return the register that holds the
 | |
| ** result.  For IN operators or if an error occurs, the return value is 0.
 | |
| */
 | |
| #ifndef SQLITE_OMIT_SUBQUERY
 | |
| int sqlite3CodeSubselect(
 | |
|   Parse *pParse,          /* Parsing context */
 | |
|   Expr *pExpr,            /* The IN, SELECT, or EXISTS operator */
 | |
|   int rHasNullFlag,       /* Register that records whether NULLs exist in RHS */
 | |
|   int isRowid             /* If true, LHS of IN operator is a rowid */
 | |
| ){
 | |
|   int jmpIfDynamic = -1;                      /* One-time test address */
 | |
|   int rReg = 0;                           /* Register storing resulting */
 | |
|   Vdbe *v = sqlite3GetVdbe(pParse);
 | |
|   if( NEVER(v==0) ) return 0;
 | |
|   sqlite3ExprCachePush(pParse);
 | |
| 
 | |
|   /* This code must be run in its entirety every time it is encountered
 | |
|   ** if any of the following is true:
 | |
|   **
 | |
|   **    *  The right-hand side is a correlated subquery
 | |
|   **    *  The right-hand side is an expression list containing variables
 | |
|   **    *  We are inside a trigger
 | |
|   **
 | |
|   ** If all of the above are false, then we can run this code just once
 | |
|   ** save the results, and reuse the same result on subsequent invocations.
 | |
|   */
 | |
|   if( !ExprHasProperty(pExpr, EP_VarSelect) ){
 | |
|     jmpIfDynamic = sqlite3CodeOnce(pParse); VdbeCoverage(v);
 | |
|   }
 | |
| 
 | |
| #ifndef SQLITE_OMIT_EXPLAIN
 | |
|   if( pParse->explain==2 ){
 | |
|     char *zMsg = sqlite3MPrintf(pParse->db, "EXECUTE %s%s SUBQUERY %d",
 | |
|         jmpIfDynamic>=0?"":"CORRELATED ",
 | |
|         pExpr->op==TK_IN?"LIST":"SCALAR",
 | |
|         pParse->iNextSelectId
 | |
|     );
 | |
|     sqlite3VdbeAddOp4(v, OP_Explain, pParse->iSelectId, 0, 0, zMsg, P4_DYNAMIC);
 | |
|   }
 | |
| #endif
 | |
| 
 | |
|   switch( pExpr->op ){
 | |
|     case TK_IN: {
 | |
|       char affinity;              /* Affinity of the LHS of the IN */
 | |
|       int addr;                   /* Address of OP_OpenEphemeral instruction */
 | |
|       Expr *pLeft = pExpr->pLeft; /* the LHS of the IN operator */
 | |
|       KeyInfo *pKeyInfo = 0;      /* Key information */
 | |
| 
 | |
|       affinity = sqlite3ExprAffinity(pLeft);
 | |
| 
 | |
|       /* Whether this is an 'x IN(SELECT...)' or an 'x IN(<exprlist>)'
 | |
|       ** expression it is handled the same way.  An ephemeral table is 
 | |
|       ** filled with single-field index keys representing the results
 | |
|       ** from the SELECT or the <exprlist>.
 | |
|       **
 | |
|       ** If the 'x' expression is a column value, or the SELECT...
 | |
|       ** statement returns a column value, then the affinity of that
 | |
|       ** column is used to build the index keys. If both 'x' and the
 | |
|       ** SELECT... statement are columns, then numeric affinity is used
 | |
|       ** if either column has NUMERIC or INTEGER affinity. If neither
 | |
|       ** 'x' nor the SELECT... statement are columns, then numeric affinity
 | |
|       ** is used.
 | |
|       */
 | |
|       pExpr->iTable = pParse->nTab++;
 | |
|       addr = sqlite3VdbeAddOp2(v, OP_OpenEphemeral, pExpr->iTable, !isRowid);
 | |
|       pKeyInfo = isRowid ? 0 : sqlite3KeyInfoAlloc(pParse->db, 1, 1);
 | |
| 
 | |
|       if( ExprHasProperty(pExpr, EP_xIsSelect) ){
 | |
|         /* Case 1:     expr IN (SELECT ...)
 | |
|         **
 | |
|         ** Generate code to write the results of the select into the temporary
 | |
|         ** table allocated and opened above.
 | |
|         */
 | |
|         Select *pSelect = pExpr->x.pSelect;
 | |
|         SelectDest dest;
 | |
|         ExprList *pEList;
 | |
| 
 | |
|         assert( !isRowid );
 | |
|         sqlite3SelectDestInit(&dest, SRT_Set, pExpr->iTable);
 | |
|         dest.affSdst = (u8)affinity;
 | |
|         assert( (pExpr->iTable&0x0000FFFF)==pExpr->iTable );
 | |
|         pSelect->iLimit = 0;
 | |
|         testcase( pSelect->selFlags & SF_Distinct );
 | |
|         testcase( pKeyInfo==0 ); /* Caused by OOM in sqlite3KeyInfoAlloc() */
 | |
|         if( sqlite3Select(pParse, pSelect, &dest) ){
 | |
|           sqlite3KeyInfoUnref(pKeyInfo);
 | |
|           return 0;
 | |
|         }
 | |
|         pEList = pSelect->pEList;
 | |
|         assert( pKeyInfo!=0 ); /* OOM will cause exit after sqlite3Select() */
 | |
|         assert( pEList!=0 );
 | |
|         assert( pEList->nExpr>0 );
 | |
|         assert( sqlite3KeyInfoIsWriteable(pKeyInfo) );
 | |
|         pKeyInfo->aColl[0] = sqlite3BinaryCompareCollSeq(pParse, pExpr->pLeft,
 | |
|                                                          pEList->a[0].pExpr);
 | |
|       }else if( ALWAYS(pExpr->x.pList!=0) ){
 | |
|         /* Case 2:     expr IN (exprlist)
 | |
|         **
 | |
|         ** For each expression, build an index key from the evaluation and
 | |
|         ** store it in the temporary table. If <expr> is a column, then use
 | |
|         ** that columns affinity when building index keys. If <expr> is not
 | |
|         ** a column, use numeric affinity.
 | |
|         */
 | |
|         int i;
 | |
|         ExprList *pList = pExpr->x.pList;
 | |
|         struct ExprList_item *pItem;
 | |
|         int r1, r2, r3;
 | |
| 
 | |
|         if( !affinity ){
 | |
|           affinity = SQLITE_AFF_BLOB;
 | |
|         }
 | |
|         if( pKeyInfo ){
 | |
|           assert( sqlite3KeyInfoIsWriteable(pKeyInfo) );
 | |
|           pKeyInfo->aColl[0] = sqlite3ExprCollSeq(pParse, pExpr->pLeft);
 | |
|         }
 | |
| 
 | |
|         /* Loop through each expression in <exprlist>. */
 | |
|         r1 = sqlite3GetTempReg(pParse);
 | |
|         r2 = sqlite3GetTempReg(pParse);
 | |
|         if( isRowid ) sqlite3VdbeAddOp2(v, OP_Null, 0, r2);
 | |
|         for(i=pList->nExpr, pItem=pList->a; i>0; i--, pItem++){
 | |
|           Expr *pE2 = pItem->pExpr;
 | |
|           int iValToIns;
 | |
| 
 | |
|           /* If the expression is not constant then we will need to
 | |
|           ** disable the test that was generated above that makes sure
 | |
|           ** this code only executes once.  Because for a non-constant
 | |
|           ** expression we need to rerun this code each time.
 | |
|           */
 | |
|           if( jmpIfDynamic>=0 && !sqlite3ExprIsConstant(pE2) ){
 | |
|             sqlite3VdbeChangeToNoop(v, jmpIfDynamic);
 | |
|             jmpIfDynamic = -1;
 | |
|           }
 | |
| 
 | |
|           /* Evaluate the expression and insert it into the temp table */
 | |
|           if( isRowid && sqlite3ExprIsInteger(pE2, &iValToIns) ){
 | |
|             sqlite3VdbeAddOp3(v, OP_InsertInt, pExpr->iTable, r2, iValToIns);
 | |
|           }else{
 | |
|             r3 = sqlite3ExprCodeTarget(pParse, pE2, r1);
 | |
|             if( isRowid ){
 | |
|               sqlite3VdbeAddOp2(v, OP_MustBeInt, r3,
 | |
|                                 sqlite3VdbeCurrentAddr(v)+2);
 | |
|               VdbeCoverage(v);
 | |
|               sqlite3VdbeAddOp3(v, OP_Insert, pExpr->iTable, r2, r3);
 | |
|             }else{
 | |
|               sqlite3VdbeAddOp4(v, OP_MakeRecord, r3, 1, r2, &affinity, 1);
 | |
|               sqlite3ExprCacheAffinityChange(pParse, r3, 1);
 | |
|               sqlite3VdbeAddOp2(v, OP_IdxInsert, pExpr->iTable, r2);
 | |
|             }
 | |
|           }
 | |
|         }
 | |
|         sqlite3ReleaseTempReg(pParse, r1);
 | |
|         sqlite3ReleaseTempReg(pParse, r2);
 | |
|       }
 | |
|       if( pKeyInfo ){
 | |
|         sqlite3VdbeChangeP4(v, addr, (void *)pKeyInfo, P4_KEYINFO);
 | |
|       }
 | |
|       break;
 | |
|     }
 | |
| 
 | |
|     case TK_EXISTS:
 | |
|     case TK_SELECT:
 | |
|     default: {
 | |
|       /* If 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.  If this is an EXISTS, write
 | |
|       ** an integer 0 (not exists) or 1 (exists) into a memory cell
 | |
|       ** and record that memory cell in iColumn.
 | |
|       */
 | |
|       Select *pSel;                         /* SELECT statement to encode */
 | |
|       SelectDest dest;                      /* How to deal with SELECt result */
 | |
| 
 | |
|       testcase( pExpr->op==TK_EXISTS );
 | |
|       testcase( pExpr->op==TK_SELECT );
 | |
|       assert( pExpr->op==TK_EXISTS || pExpr->op==TK_SELECT );
 | |
| 
 | |
|       assert( ExprHasProperty(pExpr, EP_xIsSelect) );
 | |
|       pSel = pExpr->x.pSelect;
 | |
|       sqlite3SelectDestInit(&dest, 0, ++pParse->nMem);
 | |
|       if( pExpr->op==TK_SELECT ){
 | |
|         dest.eDest = SRT_Mem;
 | |
|         dest.iSdst = dest.iSDParm;
 | |
|         sqlite3VdbeAddOp2(v, OP_Null, 0, dest.iSDParm);
 | |
|         VdbeComment((v, "Init subquery result"));
 | |
|       }else{
 | |
|         dest.eDest = SRT_Exists;
 | |
|         sqlite3VdbeAddOp2(v, OP_Integer, 0, dest.iSDParm);
 | |
|         VdbeComment((v, "Init EXISTS result"));
 | |
|       }
 | |
|       sqlite3ExprDelete(pParse->db, pSel->pLimit);
 | |
|       pSel->pLimit = sqlite3PExpr(pParse, TK_INTEGER, 0, 0,
 | |
|                                   &sqlite3IntTokens[1]);
 | |
|       pSel->iLimit = 0;
 | |
|       pSel->selFlags &= ~SF_MultiValue;
 | |
|       if( sqlite3Select(pParse, pSel, &dest) ){
 | |
|         return 0;
 | |
|       }
 | |
|       rReg = dest.iSDParm;
 | |
|       ExprSetVVAProperty(pExpr, EP_NoReduce);
 | |
|       break;
 | |
|     }
 | |
|   }
 | |
| 
 | |
|   if( rHasNullFlag ){
 | |
|     sqlite3SetHasNullFlag(v, pExpr->iTable, rHasNullFlag);
 | |
|   }
 | |
| 
 | |
|   if( jmpIfDynamic>=0 ){
 | |
|     sqlite3VdbeJumpHere(v, jmpIfDynamic);
 | |
|   }
 | |
|   sqlite3ExprCachePop(pParse);
 | |
| 
 | |
|   return rReg;
 | |
| }
 | |
| #endif /* SQLITE_OMIT_SUBQUERY */
 | |
| 
 | |
| #ifndef SQLITE_OMIT_SUBQUERY
 | |
| /*
 | |
| ** Generate code for an IN expression.
 | |
| **
 | |
| **      x IN (SELECT ...)
 | |
| **      x IN (value, value, ...)
 | |
| **
 | |
| ** The left-hand side (LHS) is a scalar expression.  The right-hand side (RHS)
 | |
| ** is an array of zero or more values.  The expression is true if the LHS is
 | |
| ** contained within the RHS.  The value of the expression is unknown (NULL)
 | |
| ** if the LHS is NULL or if the LHS is not contained within the RHS and the
 | |
| ** RHS contains one or more NULL values.
 | |
| **
 | |
| ** This routine generates code that jumps to destIfFalse if the LHS is not 
 | |
| ** contained within the RHS.  If due to NULLs we cannot determine if the LHS
 | |
| ** is contained in the RHS then jump to destIfNull.  If the LHS is contained
 | |
| ** within the RHS then fall through.
 | |
| */
 | |
| static void sqlite3ExprCodeIN(
 | |
|   Parse *pParse,        /* Parsing and code generating context */
 | |
|   Expr *pExpr,          /* The IN expression */
 | |
|   int destIfFalse,      /* Jump here if LHS is not contained in the RHS */
 | |
|   int destIfNull        /* Jump here if the results are unknown due to NULLs */
 | |
| ){
 | |
|   int rRhsHasNull = 0;  /* Register that is true if RHS contains NULL values */
 | |
|   char affinity;        /* Comparison affinity to use */
 | |
|   int eType;            /* Type of the RHS */
 | |
|   int r1;               /* Temporary use register */
 | |
|   Vdbe *v;              /* Statement under construction */
 | |
| 
 | |
|   /* Compute the RHS.   After this step, the table with cursor
 | |
|   ** pExpr->iTable will contains the values that make up the RHS.
 | |
|   */
 | |
|   v = pParse->pVdbe;
 | |
|   assert( v!=0 );       /* OOM detected prior to this routine */
 | |
|   VdbeNoopComment((v, "begin IN expr"));
 | |
|   eType = sqlite3FindInIndex(pParse, pExpr,
 | |
|                              IN_INDEX_MEMBERSHIP | IN_INDEX_NOOP_OK,
 | |
|                              destIfFalse==destIfNull ? 0 : &rRhsHasNull);
 | |
| 
 | |
|   /* Figure out the affinity to use to create a key from the results
 | |
|   ** of the expression. affinityStr stores a static string suitable for
 | |
|   ** P4 of OP_MakeRecord.
 | |
|   */
 | |
|   affinity = comparisonAffinity(pExpr);
 | |
| 
 | |
|   /* Code the LHS, the <expr> from "<expr> IN (...)".
 | |
|   */
 | |
|   sqlite3ExprCachePush(pParse);
 | |
|   r1 = sqlite3GetTempReg(pParse);
 | |
|   sqlite3ExprCode(pParse, pExpr->pLeft, r1);
 | |
| 
 | |
|   /* If sqlite3FindInIndex() did not find or create an index that is
 | |
|   ** suitable for evaluating the IN operator, then evaluate using a
 | |
|   ** sequence of comparisons.
 | |
|   */
 | |
|   if( eType==IN_INDEX_NOOP ){
 | |
|     ExprList *pList = pExpr->x.pList;
 | |
|     CollSeq *pColl = sqlite3ExprCollSeq(pParse, pExpr->pLeft);
 | |
|     int labelOk = sqlite3VdbeMakeLabel(v);
 | |
|     int r2, regToFree;
 | |
|     int regCkNull = 0;
 | |
|     int ii;
 | |
|     assert( !ExprHasProperty(pExpr, EP_xIsSelect) );
 | |
|     if( destIfNull!=destIfFalse ){
 | |
|       regCkNull = sqlite3GetTempReg(pParse);
 | |
|       sqlite3VdbeAddOp3(v, OP_BitAnd, r1, r1, regCkNull);
 | |
|     }
 | |
|     for(ii=0; ii<pList->nExpr; ii++){
 | |
|       r2 = sqlite3ExprCodeTemp(pParse, pList->a[ii].pExpr, ®ToFree);
 | |
|       if( regCkNull && sqlite3ExprCanBeNull(pList->a[ii].pExpr) ){
 | |
|         sqlite3VdbeAddOp3(v, OP_BitAnd, regCkNull, r2, regCkNull);
 | |
|       }
 | |
|       if( ii<pList->nExpr-1 || destIfNull!=destIfFalse ){
 | |
|         sqlite3VdbeAddOp4(v, OP_Eq, r1, labelOk, r2,
 | |
|                           (void*)pColl, P4_COLLSEQ);
 | |
|         VdbeCoverageIf(v, ii<pList->nExpr-1);
 | |
|         VdbeCoverageIf(v, ii==pList->nExpr-1);
 | |
|         sqlite3VdbeChangeP5(v, affinity);
 | |
|       }else{
 | |
|         assert( destIfNull==destIfFalse );
 | |
|         sqlite3VdbeAddOp4(v, OP_Ne, r1, destIfFalse, r2,
 | |
|                           (void*)pColl, P4_COLLSEQ); VdbeCoverage(v);
 | |
|         sqlite3VdbeChangeP5(v, affinity | SQLITE_JUMPIFNULL);
 | |
|       }
 | |
|       sqlite3ReleaseTempReg(pParse, regToFree);
 | |
|     }
 | |
|     if( regCkNull ){
 | |
|       sqlite3VdbeAddOp2(v, OP_IsNull, regCkNull, destIfNull); VdbeCoverage(v);
 | |
|       sqlite3VdbeGoto(v, destIfFalse);
 | |
|     }
 | |
|     sqlite3VdbeResolveLabel(v, labelOk);
 | |
|     sqlite3ReleaseTempReg(pParse, regCkNull);
 | |
|   }else{
 | |
|   
 | |
|     /* If the LHS is NULL, then the result is either false or NULL depending
 | |
|     ** on whether the RHS is empty or not, respectively.
 | |
|     */
 | |
|     if( sqlite3ExprCanBeNull(pExpr->pLeft) ){
 | |
|       if( destIfNull==destIfFalse ){
 | |
|         /* Shortcut for the common case where the false and NULL outcomes are
 | |
|         ** the same. */
 | |
|         sqlite3VdbeAddOp2(v, OP_IsNull, r1, destIfNull); VdbeCoverage(v);
 | |
|       }else{
 | |
|         int addr1 = sqlite3VdbeAddOp1(v, OP_NotNull, r1); VdbeCoverage(v);
 | |
|         sqlite3VdbeAddOp2(v, OP_Rewind, pExpr->iTable, destIfFalse);
 | |
|         VdbeCoverage(v);
 | |
|         sqlite3VdbeGoto(v, destIfNull);
 | |
|         sqlite3VdbeJumpHere(v, addr1);
 | |
|       }
 | |
|     }
 | |
|   
 | |
|     if( eType==IN_INDEX_ROWID ){
 | |
|       /* In this case, the RHS is the ROWID of table b-tree
 | |
|       */
 | |
|       sqlite3VdbeAddOp2(v, OP_MustBeInt, r1, destIfFalse); VdbeCoverage(v);
 | |
|       sqlite3VdbeAddOp3(v, OP_NotExists, pExpr->iTable, destIfFalse, r1);
 | |
|       VdbeCoverage(v);
 | |
|     }else{
 | |
|       /* In this case, the RHS is an index b-tree.
 | |
|       */
 | |
|       sqlite3VdbeAddOp4(v, OP_Affinity, r1, 1, 0, &affinity, 1);
 | |
|   
 | |
|       /* If the set membership test fails, then the result of the 
 | |
|       ** "x IN (...)" expression must be either 0 or NULL. If the set
 | |
|       ** contains no NULL values, then the result is 0. If the set 
 | |
|       ** contains one or more NULL values, then the result of the
 | |
|       ** expression is also NULL.
 | |
|       */
 | |
|       assert( destIfFalse!=destIfNull || rRhsHasNull==0 );
 | |
|       if( rRhsHasNull==0 ){
 | |
|         /* This branch runs if it is known at compile time that the RHS
 | |
|         ** cannot contain NULL values. This happens as the result
 | |
|         ** of a "NOT NULL" constraint in the database schema.
 | |
|         **
 | |
|         ** Also run this branch if NULL is equivalent to FALSE
 | |
|         ** for this particular IN operator.
 | |
|         */
 | |
|         sqlite3VdbeAddOp4Int(v, OP_NotFound, pExpr->iTable, destIfFalse, r1, 1);
 | |
|         VdbeCoverage(v);
 | |
|       }else{
 | |
|         /* In this branch, the RHS of the IN might contain a NULL and
 | |
|         ** the presence of a NULL on the RHS makes a difference in the
 | |
|         ** outcome.
 | |
|         */
 | |
|         int addr1;
 | |
|   
 | |
|         /* First check to see if the LHS is contained in the RHS.  If so,
 | |
|         ** then the answer is TRUE the presence of NULLs in the RHS does
 | |
|         ** not matter.  If the LHS is not contained in the RHS, then the
 | |
|         ** answer is NULL if the RHS contains NULLs and the answer is
 | |
|         ** FALSE if the RHS is NULL-free.
 | |
|         */
 | |
|         addr1 = sqlite3VdbeAddOp4Int(v, OP_Found, pExpr->iTable, 0, r1, 1);
 | |
|         VdbeCoverage(v);
 | |
|         sqlite3VdbeAddOp2(v, OP_IsNull, rRhsHasNull, destIfNull);
 | |
|         VdbeCoverage(v);
 | |
|         sqlite3VdbeGoto(v, destIfFalse);
 | |
|         sqlite3VdbeJumpHere(v, addr1);
 | |
|       }
 | |
|     }
 | |
|   }
 | |
|   sqlite3ReleaseTempReg(pParse, r1);
 | |
|   sqlite3ExprCachePop(pParse);
 | |
|   VdbeComment((v, "end IN expr"));
 | |
| }
 | |
| #endif /* SQLITE_OMIT_SUBQUERY */
 | |
| 
 | |
| #ifndef SQLITE_OMIT_FLOATING_POINT
 | |
| /*
 | |
| ** Generate an instruction that will put the floating point
 | |
| ** value described by z[0..n-1] into register iMem.
 | |
| **
 | |
| ** The z[] string will probably not be zero-terminated.  But the 
 | |
| ** z[n] character is guaranteed to be something that does not look
 | |
| ** like the continuation of the number.
 | |
| */
 | |
| static void codeReal(Vdbe *v, const char *z, int negateFlag, int iMem){
 | |
|   if( ALWAYS(z!=0) ){
 | |
|     double value;
 | |
|     sqlite3AtoF(z, &value, sqlite3Strlen30(z), SQLITE_UTF8);
 | |
|     assert( !sqlite3IsNaN(value) ); /* The new AtoF never returns NaN */
 | |
|     if( negateFlag ) value = -value;
 | |
|     sqlite3VdbeAddOp4Dup8(v, OP_Real, 0, iMem, 0, (u8*)&value, P4_REAL);
 | |
|   }
 | |
| }
 | |
| #endif
 | |
| 
 | |
| 
 | |
| /*
 | |
| ** Generate an instruction that will put the integer describe by
 | |
| ** text z[0..n-1] into register iMem.
 | |
| **
 | |
| ** Expr.u.zToken is always UTF8 and zero-terminated.
 | |
| */
 | |
| static void codeInteger(Parse *pParse, Expr *pExpr, int negFlag, int iMem){
 | |
|   Vdbe *v = pParse->pVdbe;
 | |
|   if( pExpr->flags & EP_IntValue ){
 | |
|     int i = pExpr->u.iValue;
 | |
|     assert( i>=0 );
 | |
|     if( negFlag ) i = -i;
 | |
|     sqlite3VdbeAddOp2(v, OP_Integer, i, iMem);
 | |
|   }else{
 | |
|     int c;
 | |
|     i64 value;
 | |
|     const char *z = pExpr->u.zToken;
 | |
|     assert( z!=0 );
 | |
|     c = sqlite3DecOrHexToI64(z, &value);
 | |
|     if( c==0 || (c==2 && negFlag) ){
 | |
|       if( negFlag ){ value = c==2 ? SMALLEST_INT64 : -value; }
 | |
|       sqlite3VdbeAddOp4Dup8(v, OP_Int64, 0, iMem, 0, (u8*)&value, P4_INT64);
 | |
|     }else{
 | |
| #ifdef SQLITE_OMIT_FLOATING_POINT
 | |
|       sqlite3ErrorMsg(pParse, "oversized integer: %s%s", negFlag ? "-" : "", z);
 | |
| #else
 | |
| #ifndef SQLITE_OMIT_HEX_INTEGER
 | |
|       if( sqlite3_strnicmp(z,"0x",2)==0 ){
 | |
|         sqlite3ErrorMsg(pParse, "hex literal too big: %s", z);
 | |
|       }else
 | |
| #endif
 | |
|       {
 | |
|         codeReal(v, z, negFlag, iMem);
 | |
|       }
 | |
| #endif
 | |
|     }
 | |
|   }
 | |
| }
 | |
| 
 | |
| /*
 | |
| ** Clear a cache entry.
 | |
| */
 | |
| static void cacheEntryClear(Parse *pParse, struct yColCache *p){
 | |
|   if( p->tempReg ){
 | |
|     if( pParse->nTempReg<ArraySize(pParse->aTempReg) ){
 | |
|       pParse->aTempReg[pParse->nTempReg++] = p->iReg;
 | |
|     }
 | |
|     p->tempReg = 0;
 | |
|   }
 | |
| }
 | |
| 
 | |
| 
 | |
| /*
 | |
| ** Record in the column cache that a particular column from a
 | |
| ** particular table is stored in a particular register.
 | |
| */
 | |
| void sqlite3ExprCacheStore(Parse *pParse, int iTab, int iCol, int iReg){
 | |
|   int i;
 | |
|   int minLru;
 | |
|   int idxLru;
 | |
|   struct yColCache *p;
 | |
| 
 | |
|   /* Unless an error has occurred, register numbers are always positive. */
 | |
|   assert( iReg>0 || pParse->nErr || pParse->db->mallocFailed );
 | |
|   assert( iCol>=-1 && iCol<32768 );  /* Finite column numbers */
 | |
| 
 | |
|   /* The SQLITE_ColumnCache flag disables the column cache.  This is used
 | |
|   ** for testing only - to verify that SQLite always gets the same answer
 | |
|   ** with and without the column cache.
 | |
|   */
 | |
|   if( OptimizationDisabled(pParse->db, SQLITE_ColumnCache) ) return;
 | |
| 
 | |
|   /* First replace any existing entry.
 | |
|   **
 | |
|   ** Actually, the way the column cache is currently used, we are guaranteed
 | |
|   ** that the object will never already be in cache.  Verify this guarantee.
 | |
|   */
 | |
| #ifndef NDEBUG
 | |
|   for(i=0, p=pParse->aColCache; i<SQLITE_N_COLCACHE; i++, p++){
 | |
|     assert( p->iReg==0 || p->iTable!=iTab || p->iColumn!=iCol );
 | |
|   }
 | |
| #endif
 | |
| 
 | |
|   /* Find an empty slot and replace it */
 | |
|   for(i=0, p=pParse->aColCache; i<SQLITE_N_COLCACHE; i++, p++){
 | |
|     if( p->iReg==0 ){
 | |
|       p->iLevel = pParse->iCacheLevel;
 | |
|       p->iTable = iTab;
 | |
|       p->iColumn = iCol;
 | |
|       p->iReg = iReg;
 | |
|       p->tempReg = 0;
 | |
|       p->lru = pParse->iCacheCnt++;
 | |
|       return;
 | |
|     }
 | |
|   }
 | |
| 
 | |
|   /* Replace the last recently used */
 | |
|   minLru = 0x7fffffff;
 | |
|   idxLru = -1;
 | |
|   for(i=0, p=pParse->aColCache; i<SQLITE_N_COLCACHE; i++, p++){
 | |
|     if( p->lru<minLru ){
 | |
|       idxLru = i;
 | |
|       minLru = p->lru;
 | |
|     }
 | |
|   }
 | |
|   if( ALWAYS(idxLru>=0) ){
 | |
|     p = &pParse->aColCache[idxLru];
 | |
|     p->iLevel = pParse->iCacheLevel;
 | |
|     p->iTable = iTab;
 | |
|     p->iColumn = iCol;
 | |
|     p->iReg = iReg;
 | |
|     p->tempReg = 0;
 | |
|     p->lru = pParse->iCacheCnt++;
 | |
|     return;
 | |
|   }
 | |
| }
 | |
| 
 | |
| /*
 | |
| ** Indicate that registers between iReg..iReg+nReg-1 are being overwritten.
 | |
| ** Purge the range of registers from the column cache.
 | |
| */
 | |
| void sqlite3ExprCacheRemove(Parse *pParse, int iReg, int nReg){
 | |
|   int i;
 | |
|   int iLast = iReg + nReg - 1;
 | |
|   struct yColCache *p;
 | |
|   for(i=0, p=pParse->aColCache; i<SQLITE_N_COLCACHE; i++, p++){
 | |
|     int r = p->iReg;
 | |
|     if( r>=iReg && r<=iLast ){
 | |
|       cacheEntryClear(pParse, p);
 | |
|       p->iReg = 0;
 | |
|     }
 | |
|   }
 | |
| }
 | |
| 
 | |
| /*
 | |
| ** Remember the current column cache context.  Any new entries added
 | |
| ** added to the column cache after this call are removed when the
 | |
| ** corresponding pop occurs.
 | |
| */
 | |
| void sqlite3ExprCachePush(Parse *pParse){
 | |
|   pParse->iCacheLevel++;
 | |
| #ifdef SQLITE_DEBUG
 | |
|   if( pParse->db->flags & SQLITE_VdbeAddopTrace ){
 | |
|     printf("PUSH to %d\n", pParse->iCacheLevel);
 | |
|   }
 | |
| #endif
 | |
| }
 | |
| 
 | |
| /*
 | |
| ** Remove from the column cache any entries that were added since the
 | |
| ** the previous sqlite3ExprCachePush operation.  In other words, restore
 | |
| ** the cache to the state it was in prior the most recent Push.
 | |
| */
 | |
| void sqlite3ExprCachePop(Parse *pParse){
 | |
|   int i;
 | |
|   struct yColCache *p;
 | |
|   assert( pParse->iCacheLevel>=1 );
 | |
|   pParse->iCacheLevel--;
 | |
| #ifdef SQLITE_DEBUG
 | |
|   if( pParse->db->flags & SQLITE_VdbeAddopTrace ){
 | |
|     printf("POP  to %d\n", pParse->iCacheLevel);
 | |
|   }
 | |
| #endif
 | |
|   for(i=0, p=pParse->aColCache; i<SQLITE_N_COLCACHE; i++, p++){
 | |
|     if( p->iReg && p->iLevel>pParse->iCacheLevel ){
 | |
|       cacheEntryClear(pParse, p);
 | |
|       p->iReg = 0;
 | |
|     }
 | |
|   }
 | |
| }
 | |
| 
 | |
| /*
 | |
| ** When a cached column is reused, make sure that its register is
 | |
| ** no longer available as a temp register.  ticket #3879:  that same
 | |
| ** register might be in the cache in multiple places, so be sure to
 | |
| ** get them all.
 | |
| */
 | |
| static void sqlite3ExprCachePinRegister(Parse *pParse, int iReg){
 | |
|   int i;
 | |
|   struct yColCache *p;
 | |
|   for(i=0, p=pParse->aColCache; i<SQLITE_N_COLCACHE; i++, p++){
 | |
|     if( p->iReg==iReg ){
 | |
|       p->tempReg = 0;
 | |
|     }
 | |
|   }
 | |
| }
 | |
| 
 | |
| /* Generate code that will load into register regOut a value that is
 | |
| ** appropriate for the iIdxCol-th column of index pIdx.
 | |
| */
 | |
| void sqlite3ExprCodeLoadIndexColumn(
 | |
|   Parse *pParse,  /* The parsing context */
 | |
|   Index *pIdx,    /* The index whose column is to be loaded */
 | |
|   int iTabCur,    /* Cursor pointing to a table row */
 | |
|   int iIdxCol,    /* The column of the index to be loaded */
 | |
|   int regOut      /* Store the index column value in this register */
 | |
| ){
 | |
|   i16 iTabCol = pIdx->aiColumn[iIdxCol];
 | |
|   if( iTabCol==XN_EXPR ){
 | |
|     assert( pIdx->aColExpr );
 | |
|     assert( pIdx->aColExpr->nExpr>iIdxCol );
 | |
|     pParse->iSelfTab = iTabCur;
 | |
|     sqlite3ExprCodeCopy(pParse, pIdx->aColExpr->a[iIdxCol].pExpr, regOut);
 | |
|   }else{
 | |
|     sqlite3ExprCodeGetColumnOfTable(pParse->pVdbe, pIdx->pTable, iTabCur,
 | |
|                                     iTabCol, regOut);
 | |
|   }
 | |
| }
 | |
| 
 | |
| /*
 | |
| ** Generate code to extract the value of the iCol-th column of a table.
 | |
| */
 | |
| void sqlite3ExprCodeGetColumnOfTable(
 | |
|   Vdbe *v,        /* The VDBE under construction */
 | |
|   Table *pTab,    /* The table containing the value */
 | |
|   int iTabCur,    /* The table cursor.  Or the PK cursor for WITHOUT ROWID */
 | |
|   int iCol,       /* Index of the column to extract */
 | |
|   int regOut      /* Extract the value into this register */
 | |
| ){
 | |
|   if( iCol<0 || iCol==pTab->iPKey ){
 | |
|     sqlite3VdbeAddOp2(v, OP_Rowid, iTabCur, regOut);
 | |
|   }else{
 | |
|     int op = IsVirtual(pTab) ? OP_VColumn : OP_Column;
 | |
|     int x = iCol;
 | |
|     if( !HasRowid(pTab) ){
 | |
|       x = sqlite3ColumnOfIndex(sqlite3PrimaryKeyIndex(pTab), iCol);
 | |
|     }
 | |
|     sqlite3VdbeAddOp3(v, op, iTabCur, x, regOut);
 | |
|   }
 | |
|   if( iCol>=0 ){
 | |
|     sqlite3ColumnDefault(v, pTab, iCol, regOut);
 | |
|   }
 | |
| }
 | |
| 
 | |
| /*
 | |
| ** Generate code that will extract the iColumn-th column from
 | |
| ** table pTab and store the column value in a register. 
 | |
| **
 | |
| ** An effort is made to store the column value in register iReg.  This
 | |
| ** is not garanteeed for GetColumn() - the result can be stored in
 | |
| ** any register.  But the result is guaranteed to land in register iReg
 | |
| ** for GetColumnToReg().
 | |
| **
 | |
| ** There must be an open cursor to pTab in iTable when this routine
 | |
| ** is called.  If iColumn<0 then code is generated that extracts the rowid.
 | |
| */
 | |
| int sqlite3ExprCodeGetColumn(
 | |
|   Parse *pParse,   /* Parsing and code generating context */
 | |
|   Table *pTab,     /* Description of the table we are reading from */
 | |
|   int iColumn,     /* Index of the table column */
 | |
|   int iTable,      /* The cursor pointing to the table */
 | |
|   int iReg,        /* Store results here */
 | |
|   u8 p5            /* P5 value for OP_Column + FLAGS */
 | |
| ){
 | |
|   Vdbe *v = pParse->pVdbe;
 | |
|   int i;
 | |
|   struct yColCache *p;
 | |
| 
 | |
|   for(i=0, p=pParse->aColCache; i<SQLITE_N_COLCACHE; i++, p++){
 | |
|     if( p->iReg>0 && p->iTable==iTable && p->iColumn==iColumn ){
 | |
|       p->lru = pParse->iCacheCnt++;
 | |
|       sqlite3ExprCachePinRegister(pParse, p->iReg);
 | |
|       return p->iReg;
 | |
|     }
 | |
|   }  
 | |
|   assert( v!=0 );
 | |
|   sqlite3ExprCodeGetColumnOfTable(v, pTab, iTable, iColumn, iReg);
 | |
|   if( p5 ){
 | |
|     sqlite3VdbeChangeP5(v, p5);
 | |
|   }else{   
 | |
|     sqlite3ExprCacheStore(pParse, iTable, iColumn, iReg);
 | |
|   }
 | |
|   return iReg;
 | |
| }
 | |
| void sqlite3ExprCodeGetColumnToReg(
 | |
|   Parse *pParse,   /* Parsing and code generating context */
 | |
|   Table *pTab,     /* Description of the table we are reading from */
 | |
|   int iColumn,     /* Index of the table column */
 | |
|   int iTable,      /* The cursor pointing to the table */
 | |
|   int iReg         /* Store results here */
 | |
| ){
 | |
|   int r1 = sqlite3ExprCodeGetColumn(pParse, pTab, iColumn, iTable, iReg, 0);
 | |
|   if( r1!=iReg ) sqlite3VdbeAddOp2(pParse->pVdbe, OP_SCopy, r1, iReg);
 | |
| }
 | |
| 
 | |
| 
 | |
| /*
 | |
| ** Clear all column cache entries.
 | |
| */
 | |
| void sqlite3ExprCacheClear(Parse *pParse){
 | |
|   int i;
 | |
|   struct yColCache *p;
 | |
| 
 | |
| #if SQLITE_DEBUG
 | |
|   if( pParse->db->flags & SQLITE_VdbeAddopTrace ){
 | |
|     printf("CLEAR\n");
 | |
|   }
 | |
| #endif
 | |
|   for(i=0, p=pParse->aColCache; i<SQLITE_N_COLCACHE; i++, p++){
 | |
|     if( p->iReg ){
 | |
|       cacheEntryClear(pParse, p);
 | |
|       p->iReg = 0;
 | |
|     }
 | |
|   }
 | |
| }
 | |
| 
 | |
| /*
 | |
| ** Record the fact that an affinity change has occurred on iCount
 | |
| ** registers starting with iStart.
 | |
| */
 | |
| void sqlite3ExprCacheAffinityChange(Parse *pParse, int iStart, int iCount){
 | |
|   sqlite3ExprCacheRemove(pParse, iStart, iCount);
 | |
| }
 | |
| 
 | |
| /*
 | |
| ** Generate code to move content from registers iFrom...iFrom+nReg-1
 | |
| ** over to iTo..iTo+nReg-1. Keep the column cache up-to-date.
 | |
| */
 | |
| void sqlite3ExprCodeMove(Parse *pParse, int iFrom, int iTo, int nReg){
 | |
|   assert( iFrom>=iTo+nReg || iFrom+nReg<=iTo );
 | |
|   sqlite3VdbeAddOp3(pParse->pVdbe, OP_Move, iFrom, iTo, nReg);
 | |
|   sqlite3ExprCacheRemove(pParse, iFrom, nReg);
 | |
| }
 | |
| 
 | |
| #if defined(SQLITE_DEBUG) || defined(SQLITE_COVERAGE_TEST)
 | |
| /*
 | |
| ** Return true if any register in the range iFrom..iTo (inclusive)
 | |
| ** is used as part of the column cache.
 | |
| **
 | |
| ** This routine is used within assert() and testcase() macros only
 | |
| ** and does not appear in a normal build.
 | |
| */
 | |
| static int usedAsColumnCache(Parse *pParse, int iFrom, int iTo){
 | |
|   int i;
 | |
|   struct yColCache *p;
 | |
|   for(i=0, p=pParse->aColCache; i<SQLITE_N_COLCACHE; i++, p++){
 | |
|     int r = p->iReg;
 | |
|     if( r>=iFrom && r<=iTo ) return 1;    /*NO_TEST*/
 | |
|   }
 | |
|   return 0;
 | |
| }
 | |
| #endif /* SQLITE_DEBUG || SQLITE_COVERAGE_TEST */
 | |
| 
 | |
| /*
 | |
| ** Convert an expression node to a TK_REGISTER
 | |
| */
 | |
| static void exprToRegister(Expr *p, int iReg){
 | |
|   p->op2 = p->op;
 | |
|   p->op = TK_REGISTER;
 | |
|   p->iTable = iReg;
 | |
|   ExprClearProperty(p, EP_Skip);
 | |
| }
 | |
| 
 | |
| /*
 | |
| ** Generate code into the current Vdbe to evaluate the given
 | |
| ** expression.  Attempt to store the results in register "target".
 | |
| ** Return the register where results are stored.
 | |
| **
 | |
| ** With this routine, there is no guarantee that results will
 | |
| ** be stored in target.  The result might be stored in some other
 | |
| ** register if it is convenient to do so.  The calling function
 | |
| ** must check the return code and move the results to the desired
 | |
| ** register.
 | |
| */
 | |
| int sqlite3ExprCodeTarget(Parse *pParse, Expr *pExpr, int target){
 | |
|   Vdbe *v = pParse->pVdbe;  /* The VM under construction */
 | |
|   int op;                   /* The opcode being coded */
 | |
|   int inReg = target;       /* Results stored in register inReg */
 | |
|   int regFree1 = 0;         /* If non-zero free this temporary register */
 | |
|   int regFree2 = 0;         /* If non-zero free this temporary register */
 | |
|   int r1, r2, r3, r4;       /* Various register numbers */
 | |
|   sqlite3 *db = pParse->db; /* The database connection */
 | |
|   Expr tempX;               /* Temporary expression node */
 | |
| 
 | |
|   assert( target>0 && target<=pParse->nMem );
 | |
|   if( v==0 ){
 | |
|     assert( pParse->db->mallocFailed );
 | |
|     return 0;
 | |
|   }
 | |
| 
 | |
|   if( pExpr==0 ){
 | |
|     op = TK_NULL;
 | |
|   }else{
 | |
|     op = pExpr->op;
 | |
|   }
 | |
|   switch( op ){
 | |
|     case TK_AGG_COLUMN: {
 | |
|       AggInfo *pAggInfo = pExpr->pAggInfo;
 | |
|       struct AggInfo_col *pCol = &pAggInfo->aCol[pExpr->iAgg];
 | |
|       if( !pAggInfo->directMode ){
 | |
|         assert( pCol->iMem>0 );
 | |
|         inReg = pCol->iMem;
 | |
|         break;
 | |
|       }else if( pAggInfo->useSortingIdx ){
 | |
|         sqlite3VdbeAddOp3(v, OP_Column, pAggInfo->sortingIdxPTab,
 | |
|                               pCol->iSorterColumn, target);
 | |
|         break;
 | |
|       }
 | |
|       /* Otherwise, fall thru into the TK_COLUMN case */
 | |
|     }
 | |
|     case TK_COLUMN: {
 | |
|       int iTab = pExpr->iTable;
 | |
|       if( iTab<0 ){
 | |
|         if( pParse->ckBase>0 ){
 | |
|           /* Generating CHECK constraints or inserting into partial index */
 | |
|           inReg = pExpr->iColumn + pParse->ckBase;
 | |
|           break;
 | |
|         }else{
 | |
|           /* Coding an expression that is part of an index where column names
 | |
|           ** in the index refer to the table to which the index belongs */
 | |
|           iTab = pParse->iSelfTab;
 | |
|         }
 | |
|       }
 | |
|       inReg = sqlite3ExprCodeGetColumn(pParse, pExpr->pTab,
 | |
|                                pExpr->iColumn, iTab, target,
 | |
|                                pExpr->op2);
 | |
|       break;
 | |
|     }
 | |
|     case TK_INTEGER: {
 | |
|       codeInteger(pParse, pExpr, 0, target);
 | |
|       break;
 | |
|     }
 | |
| #ifndef SQLITE_OMIT_FLOATING_POINT
 | |
|     case TK_FLOAT: {
 | |
|       assert( !ExprHasProperty(pExpr, EP_IntValue) );
 | |
|       codeReal(v, pExpr->u.zToken, 0, target);
 | |
|       break;
 | |
|     }
 | |
| #endif
 | |
|     case TK_STRING: {
 | |
|       assert( !ExprHasProperty(pExpr, EP_IntValue) );
 | |
|       sqlite3VdbeLoadString(v, target, pExpr->u.zToken);
 | |
|       break;
 | |
|     }
 | |
|     case TK_NULL: {
 | |
|       sqlite3VdbeAddOp2(v, OP_Null, 0, target);
 | |
|       break;
 | |
|     }
 | |
| #ifndef SQLITE_OMIT_BLOB_LITERAL
 | |
|     case TK_BLOB: {
 | |
|       int n;
 | |
|       const char *z;
 | |
|       char *zBlob;
 | |
|       assert( !ExprHasProperty(pExpr, EP_IntValue) );
 | |
|       assert( pExpr->u.zToken[0]=='x' || pExpr->u.zToken[0]=='X' );
 | |
|       assert( pExpr->u.zToken[1]=='\'' );
 | |
|       z = &pExpr->u.zToken[2];
 | |
|       n = sqlite3Strlen30(z) - 1;
 | |
|       assert( z[n]=='\'' );
 | |
|       zBlob = sqlite3HexToBlob(sqlite3VdbeDb(v), z, n);
 | |
|       sqlite3VdbeAddOp4(v, OP_Blob, n/2, target, 0, zBlob, P4_DYNAMIC);
 | |
|       break;
 | |
|     }
 | |
| #endif
 | |
|     case TK_VARIABLE: {
 | |
|       assert( !ExprHasProperty(pExpr, EP_IntValue) );
 | |
|       assert( pExpr->u.zToken!=0 );
 | |
|       assert( pExpr->u.zToken[0]!=0 );
 | |
|       sqlite3VdbeAddOp2(v, OP_Variable, pExpr->iColumn, target);
 | |
|       if( pExpr->u.zToken[1]!=0 ){
 | |
|         assert( pExpr->u.zToken[0]=='?' 
 | |
|              || strcmp(pExpr->u.zToken, pParse->azVar[pExpr->iColumn-1])==0 );
 | |
|         sqlite3VdbeChangeP4(v, -1, pParse->azVar[pExpr->iColumn-1], P4_STATIC);
 | |
|       }
 | |
|       break;
 | |
|     }
 | |
|     case TK_REGISTER: {
 | |
|       inReg = pExpr->iTable;
 | |
|       break;
 | |
|     }
 | |
| #ifndef SQLITE_OMIT_CAST
 | |
|     case TK_CAST: {
 | |
|       /* Expressions of the form:   CAST(pLeft AS token) */
 | |
|       inReg = sqlite3ExprCodeTarget(pParse, pExpr->pLeft, target);
 | |
|       if( inReg!=target ){
 | |
|         sqlite3VdbeAddOp2(v, OP_SCopy, inReg, target);
 | |
|         inReg = target;
 | |
|       }
 | |
|       sqlite3VdbeAddOp2(v, OP_Cast, target,
 | |
|                         sqlite3AffinityType(pExpr->u.zToken, 0));
 | |
|       testcase( usedAsColumnCache(pParse, inReg, inReg) );
 | |
|       sqlite3ExprCacheAffinityChange(pParse, inReg, 1);
 | |
|       break;
 | |
|     }
 | |
| #endif /* SQLITE_OMIT_CAST */
 | |
|     case TK_LT:
 | |
|     case TK_LE:
 | |
|     case TK_GT:
 | |
|     case TK_GE:
 | |
|     case TK_NE:
 | |
|     case TK_EQ: {
 | |
|       r1 = sqlite3ExprCodeTemp(pParse, pExpr->pLeft, ®Free1);
 | |
|       r2 = sqlite3ExprCodeTemp(pParse, pExpr->pRight, ®Free2);
 | |
|       codeCompare(pParse, pExpr->pLeft, pExpr->pRight, op,
 | |
|                   r1, r2, inReg, SQLITE_STOREP2);
 | |
|       assert(TK_LT==OP_Lt); testcase(op==OP_Lt); VdbeCoverageIf(v,op==OP_Lt);
 | |
|       assert(TK_LE==OP_Le); testcase(op==OP_Le); VdbeCoverageIf(v,op==OP_Le);
 | |
|       assert(TK_GT==OP_Gt); testcase(op==OP_Gt); VdbeCoverageIf(v,op==OP_Gt);
 | |
|       assert(TK_GE==OP_Ge); testcase(op==OP_Ge); VdbeCoverageIf(v,op==OP_Ge);
 | |
|       assert(TK_EQ==OP_Eq); testcase(op==OP_Eq); VdbeCoverageIf(v,op==OP_Eq);
 | |
|       assert(TK_NE==OP_Ne); testcase(op==OP_Ne); VdbeCoverageIf(v,op==OP_Ne);
 | |
|       testcase( regFree1==0 );
 | |
|       testcase( regFree2==0 );
 | |
|       break;
 | |
|     }
 | |
|     case TK_IS:
 | |
|     case TK_ISNOT: {
 | |
|       testcase( op==TK_IS );
 | |
|       testcase( op==TK_ISNOT );
 | |
|       r1 = sqlite3ExprCodeTemp(pParse, pExpr->pLeft, ®Free1);
 | |
|       r2 = sqlite3ExprCodeTemp(pParse, pExpr->pRight, ®Free2);
 | |
|       op = (op==TK_IS) ? TK_EQ : TK_NE;
 | |
|       codeCompare(pParse, pExpr->pLeft, pExpr->pRight, op,
 | |
|                   r1, r2, inReg, SQLITE_STOREP2 | SQLITE_NULLEQ);
 | |
|       VdbeCoverageIf(v, op==TK_EQ);
 | |
|       VdbeCoverageIf(v, op==TK_NE);
 | |
|       testcase( regFree1==0 );
 | |
|       testcase( regFree2==0 );
 | |
|       break;
 | |
|     }
 | |
|     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:
 | |
|     case TK_LSHIFT:
 | |
|     case TK_RSHIFT: 
 | |
|     case TK_CONCAT: {
 | |
|       assert( TK_AND==OP_And );            testcase( op==TK_AND );
 | |
|       assert( TK_OR==OP_Or );              testcase( op==TK_OR );
 | |
|       assert( TK_PLUS==OP_Add );           testcase( op==TK_PLUS );
 | |
|       assert( TK_MINUS==OP_Subtract );     testcase( op==TK_MINUS );
 | |
|       assert( TK_REM==OP_Remainder );      testcase( op==TK_REM );
 | |
|       assert( TK_BITAND==OP_BitAnd );      testcase( op==TK_BITAND );
 | |
|       assert( TK_BITOR==OP_BitOr );        testcase( op==TK_BITOR );
 | |
|       assert( TK_SLASH==OP_Divide );       testcase( op==TK_SLASH );
 | |
|       assert( TK_LSHIFT==OP_ShiftLeft );   testcase( op==TK_LSHIFT );
 | |
|       assert( TK_RSHIFT==OP_ShiftRight );  testcase( op==TK_RSHIFT );
 | |
|       assert( TK_CONCAT==OP_Concat );      testcase( op==TK_CONCAT );
 | |
|       r1 = sqlite3ExprCodeTemp(pParse, pExpr->pLeft, ®Free1);
 | |
|       r2 = sqlite3ExprCodeTemp(pParse, pExpr->pRight, ®Free2);
 | |
|       sqlite3VdbeAddOp3(v, op, r2, r1, target);
 | |
|       testcase( regFree1==0 );
 | |
|       testcase( regFree2==0 );
 | |
|       break;
 | |
|     }
 | |
|     case TK_UMINUS: {
 | |
|       Expr *pLeft = pExpr->pLeft;
 | |
|       assert( pLeft );
 | |
|       if( pLeft->op==TK_INTEGER ){
 | |
|         codeInteger(pParse, pLeft, 1, target);
 | |
| #ifndef SQLITE_OMIT_FLOATING_POINT
 | |
|       }else if( pLeft->op==TK_FLOAT ){
 | |
|         assert( !ExprHasProperty(pExpr, EP_IntValue) );
 | |
|         codeReal(v, pLeft->u.zToken, 1, target);
 | |
| #endif
 | |
|       }else{
 | |
|         tempX.op = TK_INTEGER;
 | |
|         tempX.flags = EP_IntValue|EP_TokenOnly;
 | |
|         tempX.u.iValue = 0;
 | |
|         r1 = sqlite3ExprCodeTemp(pParse, &tempX, ®Free1);
 | |
|         r2 = sqlite3ExprCodeTemp(pParse, pExpr->pLeft, ®Free2);
 | |
|         sqlite3VdbeAddOp3(v, OP_Subtract, r2, r1, target);
 | |
|         testcase( regFree2==0 );
 | |
|       }
 | |
|       inReg = target;
 | |
|       break;
 | |
|     }
 | |
|     case TK_BITNOT:
 | |
|     case TK_NOT: {
 | |
|       assert( TK_BITNOT==OP_BitNot );   testcase( op==TK_BITNOT );
 | |
|       assert( TK_NOT==OP_Not );         testcase( op==TK_NOT );
 | |
|       r1 = sqlite3ExprCodeTemp(pParse, pExpr->pLeft, ®Free1);
 | |
|       testcase( regFree1==0 );
 | |
|       inReg = target;
 | |
|       sqlite3VdbeAddOp2(v, op, r1, inReg);
 | |
|       break;
 | |
|     }
 | |
|     case TK_ISNULL:
 | |
|     case TK_NOTNULL: {
 | |
|       int addr;
 | |
|       assert( TK_ISNULL==OP_IsNull );   testcase( op==TK_ISNULL );
 | |
|       assert( TK_NOTNULL==OP_NotNull ); testcase( op==TK_NOTNULL );
 | |
|       sqlite3VdbeAddOp2(v, OP_Integer, 1, target);
 | |
|       r1 = sqlite3ExprCodeTemp(pParse, pExpr->pLeft, ®Free1);
 | |
|       testcase( regFree1==0 );
 | |
|       addr = sqlite3VdbeAddOp1(v, op, r1);
 | |
|       VdbeCoverageIf(v, op==TK_ISNULL);
 | |
|       VdbeCoverageIf(v, op==TK_NOTNULL);
 | |
|       sqlite3VdbeAddOp2(v, OP_Integer, 0, target);
 | |
|       sqlite3VdbeJumpHere(v, addr);
 | |
|       break;
 | |
|     }
 | |
|     case TK_AGG_FUNCTION: {
 | |
|       AggInfo *pInfo = pExpr->pAggInfo;
 | |
|       if( pInfo==0 ){
 | |
|         assert( !ExprHasProperty(pExpr, EP_IntValue) );
 | |
|         sqlite3ErrorMsg(pParse, "misuse of aggregate: %s()", pExpr->u.zToken);
 | |
|       }else{
 | |
|         inReg = pInfo->aFunc[pExpr->iAgg].iMem;
 | |
|       }
 | |
|       break;
 | |
|     }
 | |
|     case TK_FUNCTION: {
 | |
|       ExprList *pFarg;       /* List of function arguments */
 | |
|       int nFarg;             /* Number of function arguments */
 | |
|       FuncDef *pDef;         /* The function definition object */
 | |
|       int nId;               /* Length of the function name in bytes */
 | |
|       const char *zId;       /* The function name */
 | |
|       u32 constMask = 0;     /* Mask of function arguments that are constant */
 | |
|       int i;                 /* Loop counter */
 | |
|       u8 enc = ENC(db);      /* The text encoding used by this database */
 | |
|       CollSeq *pColl = 0;    /* A collating sequence */
 | |
| 
 | |
|       assert( !ExprHasProperty(pExpr, EP_xIsSelect) );
 | |
|       if( ExprHasProperty(pExpr, EP_TokenOnly) ){
 | |
|         pFarg = 0;
 | |
|       }else{
 | |
|         pFarg = pExpr->x.pList;
 | |
|       }
 | |
|       nFarg = pFarg ? pFarg->nExpr : 0;
 | |
|       assert( !ExprHasProperty(pExpr, EP_IntValue) );
 | |
|       zId = pExpr->u.zToken;
 | |
|       nId = sqlite3Strlen30(zId);
 | |
|       pDef = sqlite3FindFunction(db, zId, nId, nFarg, enc, 0);
 | |
|       if( pDef==0 || pDef->xFinalize!=0 ){
 | |
|         sqlite3ErrorMsg(pParse, "unknown function: %.*s()", nId, zId);
 | |
|         break;
 | |
|       }
 | |
| 
 | |
|       /* Attempt a direct implementation of the built-in COALESCE() and
 | |
|       ** IFNULL() functions.  This avoids unnecessary evaluation of
 | |
|       ** arguments past the first non-NULL argument.
 | |
|       */
 | |
|       if( pDef->funcFlags & SQLITE_FUNC_COALESCE ){
 | |
|         int endCoalesce = sqlite3VdbeMakeLabel(v);
 | |
|         assert( nFarg>=2 );
 | |
|         sqlite3ExprCode(pParse, pFarg->a[0].pExpr, target);
 | |
|         for(i=1; i<nFarg; i++){
 | |
|           sqlite3VdbeAddOp2(v, OP_NotNull, target, endCoalesce);
 | |
|           VdbeCoverage(v);
 | |
|           sqlite3ExprCacheRemove(pParse, target, 1);
 | |
|           sqlite3ExprCachePush(pParse);
 | |
|           sqlite3ExprCode(pParse, pFarg->a[i].pExpr, target);
 | |
|           sqlite3ExprCachePop(pParse);
 | |
|         }
 | |
|         sqlite3VdbeResolveLabel(v, endCoalesce);
 | |
|         break;
 | |
|       }
 | |
| 
 | |
|       /* The UNLIKELY() function is a no-op.  The result is the value
 | |
|       ** of the first argument.
 | |
|       */
 | |
|       if( pDef->funcFlags & SQLITE_FUNC_UNLIKELY ){
 | |
|         assert( nFarg>=1 );
 | |
|         inReg = sqlite3ExprCodeTarget(pParse, pFarg->a[0].pExpr, target);
 | |
|         break;
 | |
|       }
 | |
| 
 | |
|       for(i=0; i<nFarg; i++){
 | |
|         if( i<32 && sqlite3ExprIsConstant(pFarg->a[i].pExpr) ){
 | |
|           testcase( i==31 );
 | |
|           constMask |= MASKBIT32(i);
 | |
|         }
 | |
|         if( (pDef->funcFlags & SQLITE_FUNC_NEEDCOLL)!=0 && !pColl ){
 | |
|           pColl = sqlite3ExprCollSeq(pParse, pFarg->a[i].pExpr);
 | |
|         }
 | |
|       }
 | |
|       if( pFarg ){
 | |
|         if( constMask ){
 | |
|           r1 = pParse->nMem+1;
 | |
|           pParse->nMem += nFarg;
 | |
|         }else{
 | |
|           r1 = sqlite3GetTempRange(pParse, nFarg);
 | |
|         }
 | |
| 
 | |
|         /* For length() and typeof() functions with a column argument,
 | |
|         ** set the P5 parameter to the OP_Column opcode to OPFLAG_LENGTHARG
 | |
|         ** or OPFLAG_TYPEOFARG respectively, to avoid unnecessary data
 | |
|         ** loading.
 | |
|         */
 | |
|         if( (pDef->funcFlags & (SQLITE_FUNC_LENGTH|SQLITE_FUNC_TYPEOF))!=0 ){
 | |
|           u8 exprOp;
 | |
|           assert( nFarg==1 );
 | |
|           assert( pFarg->a[0].pExpr!=0 );
 | |
|           exprOp = pFarg->a[0].pExpr->op;
 | |
|           if( exprOp==TK_COLUMN || exprOp==TK_AGG_COLUMN ){
 | |
|             assert( SQLITE_FUNC_LENGTH==OPFLAG_LENGTHARG );
 | |
|             assert( SQLITE_FUNC_TYPEOF==OPFLAG_TYPEOFARG );
 | |
|             testcase( pDef->funcFlags & OPFLAG_LENGTHARG );
 | |
|             pFarg->a[0].pExpr->op2 = 
 | |
|                   pDef->funcFlags & (OPFLAG_LENGTHARG|OPFLAG_TYPEOFARG);
 | |
|           }
 | |
|         }
 | |
| 
 | |
|         sqlite3ExprCachePush(pParse);     /* Ticket 2ea2425d34be */
 | |
|         sqlite3ExprCodeExprList(pParse, pFarg, r1, 0,
 | |
|                                 SQLITE_ECEL_DUP|SQLITE_ECEL_FACTOR);
 | |
|         sqlite3ExprCachePop(pParse);      /* Ticket 2ea2425d34be */
 | |
|       }else{
 | |
|         r1 = 0;
 | |
|       }
 | |
| #ifndef SQLITE_OMIT_VIRTUALTABLE
 | |
|       /* Possibly overload the function if the first argument is
 | |
|       ** a virtual table column.
 | |
|       **
 | |
|       ** For infix functions (LIKE, GLOB, REGEXP, and MATCH) use the
 | |
|       ** second argument, not the first, as the argument to test to
 | |
|       ** see if it is a column in a virtual table.  This is done because
 | |
|       ** the left operand of infix functions (the operand we want to
 | |
|       ** control overloading) ends up as the second argument to the
 | |
|       ** function.  The expression "A glob B" is equivalent to 
 | |
|       ** "glob(B,A).  We want to use the A in "A glob B" to test
 | |
|       ** for function overloading.  But we use the B term in "glob(B,A)".
 | |
|       */
 | |
|       if( nFarg>=2 && (pExpr->flags & EP_InfixFunc) ){
 | |
|         pDef = sqlite3VtabOverloadFunction(db, pDef, nFarg, pFarg->a[1].pExpr);
 | |
|       }else if( nFarg>0 ){
 | |
|         pDef = sqlite3VtabOverloadFunction(db, pDef, nFarg, pFarg->a[0].pExpr);
 | |
|       }
 | |
| #endif
 | |
|       if( pDef->funcFlags & SQLITE_FUNC_NEEDCOLL ){
 | |
|         if( !pColl ) pColl = db->pDfltColl; 
 | |
|         sqlite3VdbeAddOp4(v, OP_CollSeq, 0, 0, 0, (char *)pColl, P4_COLLSEQ);
 | |
|       }
 | |
|       sqlite3VdbeAddOp4(v, OP_Function0, constMask, r1, target,
 | |
|                         (char*)pDef, P4_FUNCDEF);
 | |
|       sqlite3VdbeChangeP5(v, (u8)nFarg);
 | |
|       if( nFarg && constMask==0 ){
 | |
|         sqlite3ReleaseTempRange(pParse, r1, nFarg);
 | |
|       }
 | |
|       break;
 | |
|     }
 | |
| #ifndef SQLITE_OMIT_SUBQUERY
 | |
|     case TK_EXISTS:
 | |
|     case TK_SELECT: {
 | |
|       testcase( op==TK_EXISTS );
 | |
|       testcase( op==TK_SELECT );
 | |
|       inReg = sqlite3CodeSubselect(pParse, pExpr, 0, 0);
 | |
|       break;
 | |
|     }
 | |
|     case TK_IN: {
 | |
|       int destIfFalse = sqlite3VdbeMakeLabel(v);
 | |
|       int destIfNull = sqlite3VdbeMakeLabel(v);
 | |
|       sqlite3VdbeAddOp2(v, OP_Null, 0, target);
 | |
|       sqlite3ExprCodeIN(pParse, pExpr, destIfFalse, destIfNull);
 | |
|       sqlite3VdbeAddOp2(v, OP_Integer, 1, target);
 | |
|       sqlite3VdbeResolveLabel(v, destIfFalse);
 | |
|       sqlite3VdbeAddOp2(v, OP_AddImm, target, 0);
 | |
|       sqlite3VdbeResolveLabel(v, destIfNull);
 | |
|       break;
 | |
|     }
 | |
| #endif /* SQLITE_OMIT_SUBQUERY */
 | |
| 
 | |
| 
 | |
|     /*
 | |
|     **    x BETWEEN y AND z
 | |
|     **
 | |
|     ** This is equivalent to
 | |
|     **
 | |
|     **    x>=y AND x<=z
 | |
|     **
 | |
|     ** X is stored in pExpr->pLeft.
 | |
|     ** Y is stored in pExpr->pList->a[0].pExpr.
 | |
|     ** Z is stored in pExpr->pList->a[1].pExpr.
 | |
|     */
 | |
|     case TK_BETWEEN: {
 | |
|       Expr *pLeft = pExpr->pLeft;
 | |
|       struct ExprList_item *pLItem = pExpr->x.pList->a;
 | |
|       Expr *pRight = pLItem->pExpr;
 | |
| 
 | |
|       r1 = sqlite3ExprCodeTemp(pParse, pLeft, ®Free1);
 | |
|       r2 = sqlite3ExprCodeTemp(pParse, pRight, ®Free2);
 | |
|       testcase( regFree1==0 );
 | |
|       testcase( regFree2==0 );
 | |
|       r3 = sqlite3GetTempReg(pParse);
 | |
|       r4 = sqlite3GetTempReg(pParse);
 | |
|       codeCompare(pParse, pLeft, pRight, OP_Ge,
 | |
|                   r1, r2, r3, SQLITE_STOREP2);  VdbeCoverage(v);
 | |
|       pLItem++;
 | |
|       pRight = pLItem->pExpr;
 | |
|       sqlite3ReleaseTempReg(pParse, regFree2);
 | |
|       r2 = sqlite3ExprCodeTemp(pParse, pRight, ®Free2);
 | |
|       testcase( regFree2==0 );
 | |
|       codeCompare(pParse, pLeft, pRight, OP_Le, r1, r2, r4, SQLITE_STOREP2);
 | |
|       VdbeCoverage(v);
 | |
|       sqlite3VdbeAddOp3(v, OP_And, r3, r4, target);
 | |
|       sqlite3ReleaseTempReg(pParse, r3);
 | |
|       sqlite3ReleaseTempReg(pParse, r4);
 | |
|       break;
 | |
|     }
 | |
|     case TK_COLLATE: 
 | |
|     case TK_UPLUS: {
 | |
|       inReg = sqlite3ExprCodeTarget(pParse, pExpr->pLeft, target);
 | |
|       break;
 | |
|     }
 | |
| 
 | |
|     case TK_TRIGGER: {
 | |
|       /* If the opcode is TK_TRIGGER, then the expression is a reference
 | |
|       ** to a column in the new.* or old.* pseudo-tables available to
 | |
|       ** trigger programs. In this case Expr.iTable is set to 1 for the
 | |
|       ** new.* pseudo-table, or 0 for the old.* pseudo-table. Expr.iColumn
 | |
|       ** is set to the column of the pseudo-table to read, or to -1 to
 | |
|       ** read the rowid field.
 | |
|       **
 | |
|       ** The expression is implemented using an OP_Param opcode. The p1
 | |
|       ** parameter is set to 0 for an old.rowid reference, or to (i+1)
 | |
|       ** to reference another column of the old.* pseudo-table, where 
 | |
|       ** i is the index of the column. For a new.rowid reference, p1 is
 | |
|       ** set to (n+1), where n is the number of columns in each pseudo-table.
 | |
|       ** For a reference to any other column in the new.* pseudo-table, p1
 | |
|       ** is set to (n+2+i), where n and i are as defined previously. For
 | |
|       ** example, if the table on which triggers are being fired is
 | |
|       ** declared as:
 | |
|       **
 | |
|       **   CREATE TABLE t1(a, b);
 | |
|       **
 | |
|       ** Then p1 is interpreted as follows:
 | |
|       **
 | |
|       **   p1==0   ->    old.rowid     p1==3   ->    new.rowid
 | |
|       **   p1==1   ->    old.a         p1==4   ->    new.a
 | |
|       **   p1==2   ->    old.b         p1==5   ->    new.b       
 | |
|       */
 | |
|       Table *pTab = pExpr->pTab;
 | |
|       int p1 = pExpr->iTable * (pTab->nCol+1) + 1 + pExpr->iColumn;
 | |
| 
 | |
|       assert( pExpr->iTable==0 || pExpr->iTable==1 );
 | |
|       assert( pExpr->iColumn>=-1 && pExpr->iColumn<pTab->nCol );
 | |
|       assert( pTab->iPKey<0 || pExpr->iColumn!=pTab->iPKey );
 | |
|       assert( p1>=0 && p1<(pTab->nCol*2+2) );
 | |
| 
 | |
|       sqlite3VdbeAddOp2(v, OP_Param, p1, target);
 | |
|       VdbeComment((v, "%s.%s -> $%d",
 | |
|         (pExpr->iTable ? "new" : "old"),
 | |
|         (pExpr->iColumn<0 ? "rowid" : pExpr->pTab->aCol[pExpr->iColumn].zName),
 | |
|         target
 | |
|       ));
 | |
| 
 | |
| #ifndef SQLITE_OMIT_FLOATING_POINT
 | |
|       /* If the column has REAL affinity, it may currently be stored as an
 | |
|       ** integer. Use OP_RealAffinity to make sure it is really real.
 | |
|       **
 | |
|       ** EVIDENCE-OF: R-60985-57662 SQLite will convert the value back to
 | |
|       ** floating point when extracting it from the record.  */
 | |
|       if( pExpr->iColumn>=0 
 | |
|        && pTab->aCol[pExpr->iColumn].affinity==SQLITE_AFF_REAL
 | |
|       ){
 | |
|         sqlite3VdbeAddOp1(v, OP_RealAffinity, target);
 | |
|       }
 | |
| #endif
 | |
|       break;
 | |
|     }
 | |
| 
 | |
| 
 | |
|     /*
 | |
|     ** Form A:
 | |
|     **   CASE x WHEN e1 THEN r1 WHEN e2 THEN r2 ... WHEN eN THEN rN ELSE y END
 | |
|     **
 | |
|     ** Form B:
 | |
|     **   CASE WHEN e1 THEN r1 WHEN e2 THEN r2 ... WHEN eN THEN rN ELSE y END
 | |
|     **
 | |
|     ** Form A is can be transformed into the equivalent form B as follows:
 | |
|     **   CASE WHEN x=e1 THEN r1 WHEN x=e2 THEN r2 ...
 | |
|     **        WHEN x=eN THEN rN ELSE y END
 | |
|     **
 | |
|     ** X (if it exists) is in pExpr->pLeft.
 | |
|     ** Y is in the last element of pExpr->x.pList if pExpr->x.pList->nExpr is
 | |
|     ** odd.  The Y is also optional.  If the number of elements in x.pList
 | |
|     ** is even, then Y is omitted and the "otherwise" result is NULL.
 | |
|     ** Ei is in pExpr->pList->a[i*2] and Ri is pExpr->pList->a[i*2+1].
 | |
|     **
 | |
|     ** The result of the expression is the Ri for the first matching Ei,
 | |
|     ** or if there is no matching Ei, the ELSE term Y, or if there is
 | |
|     ** no ELSE term, NULL.
 | |
|     */
 | |
|     default: assert( op==TK_CASE ); {
 | |
|       int endLabel;                     /* GOTO label for end of CASE stmt */
 | |
|       int nextCase;                     /* GOTO label for next WHEN clause */
 | |
|       int nExpr;                        /* 2x number of WHEN terms */
 | |
|       int i;                            /* Loop counter */
 | |
|       ExprList *pEList;                 /* List of WHEN terms */
 | |
|       struct ExprList_item *aListelem;  /* Array of WHEN terms */
 | |
|       Expr opCompare;                   /* The X==Ei expression */
 | |
|       Expr *pX;                         /* The X expression */
 | |
|       Expr *pTest = 0;                  /* X==Ei (form A) or just Ei (form B) */
 | |
|       VVA_ONLY( int iCacheLevel = pParse->iCacheLevel; )
 | |
| 
 | |
|       assert( !ExprHasProperty(pExpr, EP_xIsSelect) && pExpr->x.pList );
 | |
|       assert(pExpr->x.pList->nExpr > 0);
 | |
|       pEList = pExpr->x.pList;
 | |
|       aListelem = pEList->a;
 | |
|       nExpr = pEList->nExpr;
 | |
|       endLabel = sqlite3VdbeMakeLabel(v);
 | |
|       if( (pX = pExpr->pLeft)!=0 ){
 | |
|         tempX = *pX;
 | |
|         testcase( pX->op==TK_COLUMN );
 | |
|         exprToRegister(&tempX, sqlite3ExprCodeTemp(pParse, pX, ®Free1));
 | |
|         testcase( regFree1==0 );
 | |
|         opCompare.op = TK_EQ;
 | |
|         opCompare.pLeft = &tempX;
 | |
|         pTest = &opCompare;
 | |
|         /* Ticket b351d95f9cd5ef17e9d9dbae18f5ca8611190001:
 | |
|         ** The value in regFree1 might get SCopy-ed into the file result.
 | |
|         ** So make sure that the regFree1 register is not reused for other
 | |
|         ** purposes and possibly overwritten.  */
 | |
|         regFree1 = 0;
 | |
|       }
 | |
|       for(i=0; i<nExpr-1; i=i+2){
 | |
|         sqlite3ExprCachePush(pParse);
 | |
|         if( pX ){
 | |
|           assert( pTest!=0 );
 | |
|           opCompare.pRight = aListelem[i].pExpr;
 | |
|         }else{
 | |
|           pTest = aListelem[i].pExpr;
 | |
|         }
 | |
|         nextCase = sqlite3VdbeMakeLabel(v);
 | |
|         testcase( pTest->op==TK_COLUMN );
 | |
|         sqlite3ExprIfFalse(pParse, pTest, nextCase, SQLITE_JUMPIFNULL);
 | |
|         testcase( aListelem[i+1].pExpr->op==TK_COLUMN );
 | |
|         sqlite3ExprCode(pParse, aListelem[i+1].pExpr, target);
 | |
|         sqlite3VdbeGoto(v, endLabel);
 | |
|         sqlite3ExprCachePop(pParse);
 | |
|         sqlite3VdbeResolveLabel(v, nextCase);
 | |
|       }
 | |
|       if( (nExpr&1)!=0 ){
 | |
|         sqlite3ExprCachePush(pParse);
 | |
|         sqlite3ExprCode(pParse, pEList->a[nExpr-1].pExpr, target);
 | |
|         sqlite3ExprCachePop(pParse);
 | |
|       }else{
 | |
|         sqlite3VdbeAddOp2(v, OP_Null, 0, target);
 | |
|       }
 | |
|       assert( db->mallocFailed || pParse->nErr>0 
 | |
|            || pParse->iCacheLevel==iCacheLevel );
 | |
|       sqlite3VdbeResolveLabel(v, endLabel);
 | |
|       break;
 | |
|     }
 | |
| #ifndef SQLITE_OMIT_TRIGGER
 | |
|     case TK_RAISE: {
 | |
|       assert( pExpr->affinity==OE_Rollback 
 | |
|            || pExpr->affinity==OE_Abort
 | |
|            || pExpr->affinity==OE_Fail
 | |
|            || pExpr->affinity==OE_Ignore
 | |
|       );
 | |
|       if( !pParse->pTriggerTab ){
 | |
|         sqlite3ErrorMsg(pParse,
 | |
|                        "RAISE() may only be used within a trigger-program");
 | |
|         return 0;
 | |
|       }
 | |
|       if( pExpr->affinity==OE_Abort ){
 | |
|         sqlite3MayAbort(pParse);
 | |
|       }
 | |
|       assert( !ExprHasProperty(pExpr, EP_IntValue) );
 | |
|       if( pExpr->affinity==OE_Ignore ){
 | |
|         sqlite3VdbeAddOp4(
 | |
|             v, OP_Halt, SQLITE_OK, OE_Ignore, 0, pExpr->u.zToken,0);
 | |
|         VdbeCoverage(v);
 | |
|       }else{
 | |
|         sqlite3HaltConstraint(pParse, SQLITE_CONSTRAINT_TRIGGER,
 | |
|                               pExpr->affinity, pExpr->u.zToken, 0, 0);
 | |
|       }
 | |
| 
 | |
|       break;
 | |
|     }
 | |
| #endif
 | |
|   }
 | |
|   sqlite3ReleaseTempReg(pParse, regFree1);
 | |
|   sqlite3ReleaseTempReg(pParse, regFree2);
 | |
|   return inReg;
 | |
| }
 | |
| 
 | |
| /*
 | |
| ** Factor out the code of the given expression to initialization time.
 | |
| */
 | |
| void sqlite3ExprCodeAtInit(
 | |
|   Parse *pParse,    /* Parsing context */
 | |
|   Expr *pExpr,      /* The expression to code when the VDBE initializes */
 | |
|   int regDest,      /* Store the value in this register */
 | |
|   u8 reusable       /* True if this expression is reusable */
 | |
| ){
 | |
|   ExprList *p;
 | |
|   assert( ConstFactorOk(pParse) );
 | |
|   p = pParse->pConstExpr;
 | |
|   pExpr = sqlite3ExprDup(pParse->db, pExpr, 0);
 | |
|   p = sqlite3ExprListAppend(pParse, p, pExpr);
 | |
|   if( p ){
 | |
|      struct ExprList_item *pItem = &p->a[p->nExpr-1];
 | |
|      pItem->u.iConstExprReg = regDest;
 | |
|      pItem->reusable = reusable;
 | |
|   }
 | |
|   pParse->pConstExpr = p;
 | |
| }
 | |
| 
 | |
| /*
 | |
| ** Generate code to evaluate an expression and store the results
 | |
| ** into a register.  Return the register number where the results
 | |
| ** are stored.
 | |
| **
 | |
| ** If the register is a temporary register that can be deallocated,
 | |
| ** then write its number into *pReg.  If the result register is not
 | |
| ** a temporary, then set *pReg to zero.
 | |
| **
 | |
| ** If pExpr is a constant, then this routine might generate this
 | |
| ** code to fill the register in the initialization section of the
 | |
| ** VDBE program, in order to factor it out of the evaluation loop.
 | |
| */
 | |
| int sqlite3ExprCodeTemp(Parse *pParse, Expr *pExpr, int *pReg){
 | |
|   int r2;
 | |
|   pExpr = sqlite3ExprSkipCollate(pExpr);
 | |
|   if( ConstFactorOk(pParse)
 | |
|    && pExpr->op!=TK_REGISTER
 | |
|    && sqlite3ExprIsConstantNotJoin(pExpr)
 | |
|   ){
 | |
|     ExprList *p = pParse->pConstExpr;
 | |
|     int i;
 | |
|     *pReg  = 0;
 | |
|     if( p ){
 | |
|       struct ExprList_item *pItem;
 | |
|       for(pItem=p->a, i=p->nExpr; i>0; pItem++, i--){
 | |
|         if( pItem->reusable && sqlite3ExprCompare(pItem->pExpr,pExpr,-1)==0 ){
 | |
|           return pItem->u.iConstExprReg;
 | |
|         }
 | |
|       }
 | |
|     }
 | |
|     r2 = ++pParse->nMem;
 | |
|     sqlite3ExprCodeAtInit(pParse, pExpr, r2, 1);
 | |
|   }else{
 | |
|     int r1 = sqlite3GetTempReg(pParse);
 | |
|     r2 = sqlite3ExprCodeTarget(pParse, pExpr, r1);
 | |
|     if( r2==r1 ){
 | |
|       *pReg = r1;
 | |
|     }else{
 | |
|       sqlite3ReleaseTempReg(pParse, r1);
 | |
|       *pReg = 0;
 | |
|     }
 | |
|   }
 | |
|   return r2;
 | |
| }
 | |
| 
 | |
| /*
 | |
| ** Generate code that will evaluate expression pExpr and store the
 | |
| ** results in register target.  The results are guaranteed to appear
 | |
| ** in register target.
 | |
| */
 | |
| void sqlite3ExprCode(Parse *pParse, Expr *pExpr, int target){
 | |
|   int inReg;
 | |
| 
 | |
|   assert( target>0 && target<=pParse->nMem );
 | |
|   if( pExpr && pExpr->op==TK_REGISTER ){
 | |
|     sqlite3VdbeAddOp2(pParse->pVdbe, OP_Copy, pExpr->iTable, target);
 | |
|   }else{
 | |
|     inReg = sqlite3ExprCodeTarget(pParse, pExpr, target);
 | |
|     assert( pParse->pVdbe!=0 || pParse->db->mallocFailed );
 | |
|     if( inReg!=target && pParse->pVdbe ){
 | |
|       sqlite3VdbeAddOp2(pParse->pVdbe, OP_SCopy, inReg, target);
 | |
|     }
 | |
|   }
 | |
| }
 | |
| 
 | |
| /*
 | |
| ** Make a transient copy of expression pExpr and then code it using
 | |
| ** sqlite3ExprCode().  This routine works just like sqlite3ExprCode()
 | |
| ** except that the input expression is guaranteed to be unchanged.
 | |
| */
 | |
| void sqlite3ExprCodeCopy(Parse *pParse, Expr *pExpr, int target){
 | |
|   sqlite3 *db = pParse->db;
 | |
|   pExpr = sqlite3ExprDup(db, pExpr, 0);
 | |
|   if( !db->mallocFailed ) sqlite3ExprCode(pParse, pExpr, target);
 | |
|   sqlite3ExprDelete(db, pExpr);
 | |
| }
 | |
| 
 | |
| /*
 | |
| ** Generate code that will evaluate expression pExpr and store the
 | |
| ** results in register target.  The results are guaranteed to appear
 | |
| ** in register target.  If the expression is constant, then this routine
 | |
| ** might choose to code the expression at initialization time.
 | |
| */
 | |
| void sqlite3ExprCodeFactorable(Parse *pParse, Expr *pExpr, int target){
 | |
|   if( pParse->okConstFactor && sqlite3ExprIsConstant(pExpr) ){
 | |
|     sqlite3ExprCodeAtInit(pParse, pExpr, target, 0);
 | |
|   }else{
 | |
|     sqlite3ExprCode(pParse, pExpr, target);
 | |
|   }
 | |
| }
 | |
| 
 | |
| /*
 | |
| ** Generate code that evaluates the given expression and puts the result
 | |
| ** in register target.
 | |
| **
 | |
| ** Also make a copy of the expression results into another "cache" register
 | |
| ** and modify the expression so that the next time it is evaluated,
 | |
| ** the result is a copy of the cache register.
 | |
| **
 | |
| ** This routine is used for expressions that are used multiple 
 | |
| ** times.  They are evaluated once and the results of the expression
 | |
| ** are reused.
 | |
| */
 | |
| void sqlite3ExprCodeAndCache(Parse *pParse, Expr *pExpr, int target){
 | |
|   Vdbe *v = pParse->pVdbe;
 | |
|   int iMem;
 | |
| 
 | |
|   assert( target>0 );
 | |
|   assert( pExpr->op!=TK_REGISTER );
 | |
|   sqlite3ExprCode(pParse, pExpr, target);
 | |
|   iMem = ++pParse->nMem;
 | |
|   sqlite3VdbeAddOp2(v, OP_Copy, target, iMem);
 | |
|   exprToRegister(pExpr, iMem);
 | |
| }
 | |
| 
 | |
| /*
 | |
| ** Generate code that pushes the value of every element of the given
 | |
| ** expression list into a sequence of registers beginning at target.
 | |
| **
 | |
| ** Return the number of elements evaluated.
 | |
| **
 | |
| ** The SQLITE_ECEL_DUP flag prevents the arguments from being
 | |
| ** filled using OP_SCopy.  OP_Copy must be used instead.
 | |
| **
 | |
| ** The SQLITE_ECEL_FACTOR argument allows constant arguments to be
 | |
| ** factored out into initialization code.
 | |
| **
 | |
| ** The SQLITE_ECEL_REF flag means that expressions in the list with
 | |
| ** ExprList.a[].u.x.iOrderByCol>0 have already been evaluated and stored
 | |
| ** in registers at srcReg, and so the value can be copied from there.
 | |
| */
 | |
| int sqlite3ExprCodeExprList(
 | |
|   Parse *pParse,     /* Parsing context */
 | |
|   ExprList *pList,   /* The expression list to be coded */
 | |
|   int target,        /* Where to write results */
 | |
|   int srcReg,        /* Source registers if SQLITE_ECEL_REF */
 | |
|   u8 flags           /* SQLITE_ECEL_* flags */
 | |
| ){
 | |
|   struct ExprList_item *pItem;
 | |
|   int i, j, n;
 | |
|   u8 copyOp = (flags & SQLITE_ECEL_DUP) ? OP_Copy : OP_SCopy;
 | |
|   Vdbe *v = pParse->pVdbe;
 | |
|   assert( pList!=0 );
 | |
|   assert( target>0 );
 | |
|   assert( pParse->pVdbe!=0 );  /* Never gets this far otherwise */
 | |
|   n = pList->nExpr;
 | |
|   if( !ConstFactorOk(pParse) ) flags &= ~SQLITE_ECEL_FACTOR;
 | |
|   for(pItem=pList->a, i=0; i<n; i++, pItem++){
 | |
|     Expr *pExpr = pItem->pExpr;
 | |
|     if( (flags & SQLITE_ECEL_REF)!=0 && (j = pList->a[i].u.x.iOrderByCol)>0 ){
 | |
|       sqlite3VdbeAddOp2(v, copyOp, j+srcReg-1, target+i);
 | |
|     }else if( (flags & SQLITE_ECEL_FACTOR)!=0 && sqlite3ExprIsConstant(pExpr) ){
 | |
|       sqlite3ExprCodeAtInit(pParse, pExpr, target+i, 0);
 | |
|     }else{
 | |
|       int inReg = sqlite3ExprCodeTarget(pParse, pExpr, target+i);
 | |
|       if( inReg!=target+i ){
 | |
|         VdbeOp *pOp;
 | |
|         if( copyOp==OP_Copy
 | |
|          && (pOp=sqlite3VdbeGetOp(v, -1))->opcode==OP_Copy
 | |
|          && pOp->p1+pOp->p3+1==inReg
 | |
|          && pOp->p2+pOp->p3+1==target+i
 | |
|         ){
 | |
|           pOp->p3++;
 | |
|         }else{
 | |
|           sqlite3VdbeAddOp2(v, copyOp, inReg, target+i);
 | |
|         }
 | |
|       }
 | |
|     }
 | |
|   }
 | |
|   return n;
 | |
| }
 | |
| 
 | |
| /*
 | |
| ** Generate code for a BETWEEN operator.
 | |
| **
 | |
| **    x BETWEEN y AND z
 | |
| **
 | |
| ** The above is equivalent to 
 | |
| **
 | |
| **    x>=y AND x<=z
 | |
| **
 | |
| ** Code it as such, taking care to do the common subexpression
 | |
| ** elimination of x.
 | |
| */
 | |
| static void exprCodeBetween(
 | |
|   Parse *pParse,    /* Parsing and code generating context */
 | |
|   Expr *pExpr,      /* The BETWEEN expression */
 | |
|   int dest,         /* Jump here if the jump is taken */
 | |
|   int jumpIfTrue,   /* Take the jump if the BETWEEN is true */
 | |
|   int jumpIfNull    /* Take the jump if the BETWEEN is NULL */
 | |
| ){
 | |
|   Expr exprAnd;     /* The AND operator in  x>=y AND x<=z  */
 | |
|   Expr compLeft;    /* The  x>=y  term */
 | |
|   Expr compRight;   /* The  x<=z  term */
 | |
|   Expr exprX;       /* The  x  subexpression */
 | |
|   int regFree1 = 0; /* Temporary use register */
 | |
| 
 | |
|   assert( !ExprHasProperty(pExpr, EP_xIsSelect) );
 | |
|   exprX = *pExpr->pLeft;
 | |
|   exprAnd.op = TK_AND;
 | |
|   exprAnd.pLeft = &compLeft;
 | |
|   exprAnd.pRight = &compRight;
 | |
|   compLeft.op = TK_GE;
 | |
|   compLeft.pLeft = &exprX;
 | |
|   compLeft.pRight = pExpr->x.pList->a[0].pExpr;
 | |
|   compRight.op = TK_LE;
 | |
|   compRight.pLeft = &exprX;
 | |
|   compRight.pRight = pExpr->x.pList->a[1].pExpr;
 | |
|   exprToRegister(&exprX, sqlite3ExprCodeTemp(pParse, &exprX, ®Free1));
 | |
|   if( jumpIfTrue ){
 | |
|     sqlite3ExprIfTrue(pParse, &exprAnd, dest, jumpIfNull);
 | |
|   }else{
 | |
|     sqlite3ExprIfFalse(pParse, &exprAnd, dest, jumpIfNull);
 | |
|   }
 | |
|   sqlite3ReleaseTempReg(pParse, regFree1);
 | |
| 
 | |
|   /* Ensure adequate test coverage */
 | |
|   testcase( jumpIfTrue==0 && jumpIfNull==0 && regFree1==0 );
 | |
|   testcase( jumpIfTrue==0 && jumpIfNull==0 && regFree1!=0 );
 | |
|   testcase( jumpIfTrue==0 && jumpIfNull!=0 && regFree1==0 );
 | |
|   testcase( jumpIfTrue==0 && jumpIfNull!=0 && regFree1!=0 );
 | |
|   testcase( jumpIfTrue!=0 && jumpIfNull==0 && regFree1==0 );
 | |
|   testcase( jumpIfTrue!=0 && jumpIfNull==0 && regFree1!=0 );
 | |
|   testcase( jumpIfTrue!=0 && jumpIfNull!=0 && regFree1==0 );
 | |
|   testcase( jumpIfTrue!=0 && jumpIfNull!=0 && regFree1!=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 SQLITE_JUMPIFNULL.
 | |
| **
 | |
| ** This code depends on the fact that certain token values (ex: TK_EQ)
 | |
| ** are the same as opcode values (ex: OP_Eq) that implement the corresponding
 | |
| ** operation.  Special comments in vdbe.c and the mkopcodeh.awk script in
 | |
| ** the make process cause these values to align.  Assert()s in the code
 | |
| ** below verify that the numbers are aligned correctly.
 | |
| */
 | |
| void sqlite3ExprIfTrue(Parse *pParse, Expr *pExpr, int dest, int jumpIfNull){
 | |
|   Vdbe *v = pParse->pVdbe;
 | |
|   int op = 0;
 | |
|   int regFree1 = 0;
 | |
|   int regFree2 = 0;
 | |
|   int r1, r2;
 | |
| 
 | |
|   assert( jumpIfNull==SQLITE_JUMPIFNULL || jumpIfNull==0 );
 | |
|   if( NEVER(v==0) )     return;  /* Existence of VDBE checked by caller */
 | |
|   if( NEVER(pExpr==0) ) return;  /* No way this can happen */
 | |
|   op = pExpr->op;
 | |
|   switch( op ){
 | |
|     case TK_AND: {
 | |
|       int d2 = sqlite3VdbeMakeLabel(v);
 | |
|       testcase( jumpIfNull==0 );
 | |
|       sqlite3ExprIfFalse(pParse, pExpr->pLeft, d2,jumpIfNull^SQLITE_JUMPIFNULL);
 | |
|       sqlite3ExprCachePush(pParse);
 | |
|       sqlite3ExprIfTrue(pParse, pExpr->pRight, dest, jumpIfNull);
 | |
|       sqlite3VdbeResolveLabel(v, d2);
 | |
|       sqlite3ExprCachePop(pParse);
 | |
|       break;
 | |
|     }
 | |
|     case TK_OR: {
 | |
|       testcase( jumpIfNull==0 );
 | |
|       sqlite3ExprIfTrue(pParse, pExpr->pLeft, dest, jumpIfNull);
 | |
|       sqlite3ExprCachePush(pParse);
 | |
|       sqlite3ExprIfTrue(pParse, pExpr->pRight, dest, jumpIfNull);
 | |
|       sqlite3ExprCachePop(pParse);
 | |
|       break;
 | |
|     }
 | |
|     case TK_NOT: {
 | |
|       testcase( jumpIfNull==0 );
 | |
|       sqlite3ExprIfFalse(pParse, pExpr->pLeft, dest, jumpIfNull);
 | |
|       break;
 | |
|     }
 | |
|     case TK_LT:
 | |
|     case TK_LE:
 | |
|     case TK_GT:
 | |
|     case TK_GE:
 | |
|     case TK_NE:
 | |
|     case TK_EQ: {
 | |
|       testcase( jumpIfNull==0 );
 | |
|       r1 = sqlite3ExprCodeTemp(pParse, pExpr->pLeft, ®Free1);
 | |
|       r2 = sqlite3ExprCodeTemp(pParse, pExpr->pRight, ®Free2);
 | |
|       codeCompare(pParse, pExpr->pLeft, pExpr->pRight, op,
 | |
|                   r1, r2, dest, jumpIfNull);
 | |
|       assert(TK_LT==OP_Lt); testcase(op==OP_Lt); VdbeCoverageIf(v,op==OP_Lt);
 | |
|       assert(TK_LE==OP_Le); testcase(op==OP_Le); VdbeCoverageIf(v,op==OP_Le);
 | |
|       assert(TK_GT==OP_Gt); testcase(op==OP_Gt); VdbeCoverageIf(v,op==OP_Gt);
 | |
|       assert(TK_GE==OP_Ge); testcase(op==OP_Ge); VdbeCoverageIf(v,op==OP_Ge);
 | |
|       assert(TK_EQ==OP_Eq); testcase(op==OP_Eq); VdbeCoverageIf(v,op==OP_Eq);
 | |
|       assert(TK_NE==OP_Ne); testcase(op==OP_Ne); VdbeCoverageIf(v,op==OP_Ne);
 | |
|       testcase( regFree1==0 );
 | |
|       testcase( regFree2==0 );
 | |
|       break;
 | |
|     }
 | |
|     case TK_IS:
 | |
|     case TK_ISNOT: {
 | |
|       testcase( op==TK_IS );
 | |
|       testcase( op==TK_ISNOT );
 | |
|       r1 = sqlite3ExprCodeTemp(pParse, pExpr->pLeft, ®Free1);
 | |
|       r2 = sqlite3ExprCodeTemp(pParse, pExpr->pRight, ®Free2);
 | |
|       op = (op==TK_IS) ? TK_EQ : TK_NE;
 | |
|       codeCompare(pParse, pExpr->pLeft, pExpr->pRight, op,
 | |
|                   r1, r2, dest, SQLITE_NULLEQ);
 | |
|       VdbeCoverageIf(v, op==TK_EQ);
 | |
|       VdbeCoverageIf(v, op==TK_NE);
 | |
|       testcase( regFree1==0 );
 | |
|       testcase( regFree2==0 );
 | |
|       break;
 | |
|     }
 | |
|     case TK_ISNULL:
 | |
|     case TK_NOTNULL: {
 | |
|       assert( TK_ISNULL==OP_IsNull );   testcase( op==TK_ISNULL );
 | |
|       assert( TK_NOTNULL==OP_NotNull ); testcase( op==TK_NOTNULL );
 | |
|       r1 = sqlite3ExprCodeTemp(pParse, pExpr->pLeft, ®Free1);
 | |
|       sqlite3VdbeAddOp2(v, op, r1, dest);
 | |
|       VdbeCoverageIf(v, op==TK_ISNULL);
 | |
|       VdbeCoverageIf(v, op==TK_NOTNULL);
 | |
|       testcase( regFree1==0 );
 | |
|       break;
 | |
|     }
 | |
|     case TK_BETWEEN: {
 | |
|       testcase( jumpIfNull==0 );
 | |
|       exprCodeBetween(pParse, pExpr, dest, 1, jumpIfNull);
 | |
|       break;
 | |
|     }
 | |
| #ifndef SQLITE_OMIT_SUBQUERY
 | |
|     case TK_IN: {
 | |
|       int destIfFalse = sqlite3VdbeMakeLabel(v);
 | |
|       int destIfNull = jumpIfNull ? dest : destIfFalse;
 | |
|       sqlite3ExprCodeIN(pParse, pExpr, destIfFalse, destIfNull);
 | |
|       sqlite3VdbeGoto(v, dest);
 | |
|       sqlite3VdbeResolveLabel(v, destIfFalse);
 | |
|       break;
 | |
|     }
 | |
| #endif
 | |
|     default: {
 | |
|       if( exprAlwaysTrue(pExpr) ){
 | |
|         sqlite3VdbeGoto(v, dest);
 | |
|       }else if( exprAlwaysFalse(pExpr) ){
 | |
|         /* No-op */
 | |
|       }else{
 | |
|         r1 = sqlite3ExprCodeTemp(pParse, pExpr, ®Free1);
 | |
|         sqlite3VdbeAddOp3(v, OP_If, r1, dest, jumpIfNull!=0);
 | |
|         VdbeCoverage(v);
 | |
|         testcase( regFree1==0 );
 | |
|         testcase( jumpIfNull==0 );
 | |
|       }
 | |
|       break;
 | |
|     }
 | |
|   }
 | |
|   sqlite3ReleaseTempReg(pParse, regFree1);
 | |
|   sqlite3ReleaseTempReg(pParse, regFree2);  
 | |
| }
 | |
| 
 | |
| /*
 | |
| ** 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 SQLITE_JUMPIFNULL or fall through if jumpIfNull
 | |
| ** is 0.
 | |
| */
 | |
| void sqlite3ExprIfFalse(Parse *pParse, Expr *pExpr, int dest, int jumpIfNull){
 | |
|   Vdbe *v = pParse->pVdbe;
 | |
|   int op = 0;
 | |
|   int regFree1 = 0;
 | |
|   int regFree2 = 0;
 | |
|   int r1, r2;
 | |
| 
 | |
|   assert( jumpIfNull==SQLITE_JUMPIFNULL || jumpIfNull==0 );
 | |
|   if( NEVER(v==0) ) return; /* Existence of VDBE checked by caller */
 | |
|   if( pExpr==0 )    return;
 | |
| 
 | |
|   /* The value of pExpr->op and op are related as follows:
 | |
|   **
 | |
|   **       pExpr->op            op
 | |
|   **       ---------          ----------
 | |
|   **       TK_ISNULL          OP_NotNull
 | |
|   **       TK_NOTNULL         OP_IsNull
 | |
|   **       TK_NE              OP_Eq
 | |
|   **       TK_EQ              OP_Ne
 | |
|   **       TK_GT              OP_Le
 | |
|   **       TK_LE              OP_Gt
 | |
|   **       TK_GE              OP_Lt
 | |
|   **       TK_LT              OP_Ge
 | |
|   **
 | |
|   ** For other values of pExpr->op, op is undefined and unused.
 | |
|   ** The value of TK_ and OP_ constants are arranged such that we
 | |
|   ** can compute the mapping above using the following expression.
 | |
|   ** Assert()s verify that the computation is correct.
 | |
|   */
 | |
|   op = ((pExpr->op+(TK_ISNULL&1))^1)-(TK_ISNULL&1);
 | |
| 
 | |
|   /* Verify correct alignment of TK_ and OP_ constants
 | |
|   */
 | |
|   assert( pExpr->op!=TK_ISNULL || op==OP_NotNull );
 | |
|   assert( pExpr->op!=TK_NOTNULL || op==OP_IsNull );
 | |
|   assert( pExpr->op!=TK_NE || op==OP_Eq );
 | |
|   assert( pExpr->op!=TK_EQ || op==OP_Ne );
 | |
|   assert( pExpr->op!=TK_LT || op==OP_Ge );
 | |
|   assert( pExpr->op!=TK_LE || op==OP_Gt );
 | |
|   assert( pExpr->op!=TK_GT || op==OP_Le );
 | |
|   assert( pExpr->op!=TK_GE || op==OP_Lt );
 | |
| 
 | |
|   switch( pExpr->op ){
 | |
|     case TK_AND: {
 | |
|       testcase( jumpIfNull==0 );
 | |
|       sqlite3ExprIfFalse(pParse, pExpr->pLeft, dest, jumpIfNull);
 | |
|       sqlite3ExprCachePush(pParse);
 | |
|       sqlite3ExprIfFalse(pParse, pExpr->pRight, dest, jumpIfNull);
 | |
|       sqlite3ExprCachePop(pParse);
 | |
|       break;
 | |
|     }
 | |
|     case TK_OR: {
 | |
|       int d2 = sqlite3VdbeMakeLabel(v);
 | |
|       testcase( jumpIfNull==0 );
 | |
|       sqlite3ExprIfTrue(pParse, pExpr->pLeft, d2, jumpIfNull^SQLITE_JUMPIFNULL);
 | |
|       sqlite3ExprCachePush(pParse);
 | |
|       sqlite3ExprIfFalse(pParse, pExpr->pRight, dest, jumpIfNull);
 | |
|       sqlite3VdbeResolveLabel(v, d2);
 | |
|       sqlite3ExprCachePop(pParse);
 | |
|       break;
 | |
|     }
 | |
|     case TK_NOT: {
 | |
|       testcase( jumpIfNull==0 );
 | |
|       sqlite3ExprIfTrue(pParse, pExpr->pLeft, dest, jumpIfNull);
 | |
|       break;
 | |
|     }
 | |
|     case TK_LT:
 | |
|     case TK_LE:
 | |
|     case TK_GT:
 | |
|     case TK_GE:
 | |
|     case TK_NE:
 | |
|     case TK_EQ: {
 | |
|       testcase( jumpIfNull==0 );
 | |
|       r1 = sqlite3ExprCodeTemp(pParse, pExpr->pLeft, ®Free1);
 | |
|       r2 = sqlite3ExprCodeTemp(pParse, pExpr->pRight, ®Free2);
 | |
|       codeCompare(pParse, pExpr->pLeft, pExpr->pRight, op,
 | |
|                   r1, r2, dest, jumpIfNull);
 | |
|       assert(TK_LT==OP_Lt); testcase(op==OP_Lt); VdbeCoverageIf(v,op==OP_Lt);
 | |
|       assert(TK_LE==OP_Le); testcase(op==OP_Le); VdbeCoverageIf(v,op==OP_Le);
 | |
|       assert(TK_GT==OP_Gt); testcase(op==OP_Gt); VdbeCoverageIf(v,op==OP_Gt);
 | |
|       assert(TK_GE==OP_Ge); testcase(op==OP_Ge); VdbeCoverageIf(v,op==OP_Ge);
 | |
|       assert(TK_EQ==OP_Eq); testcase(op==OP_Eq); VdbeCoverageIf(v,op==OP_Eq);
 | |
|       assert(TK_NE==OP_Ne); testcase(op==OP_Ne); VdbeCoverageIf(v,op==OP_Ne);
 | |
|       testcase( regFree1==0 );
 | |
|       testcase( regFree2==0 );
 | |
|       break;
 | |
|     }
 | |
|     case TK_IS:
 | |
|     case TK_ISNOT: {
 | |
|       testcase( pExpr->op==TK_IS );
 | |
|       testcase( pExpr->op==TK_ISNOT );
 | |
|       r1 = sqlite3ExprCodeTemp(pParse, pExpr->pLeft, ®Free1);
 | |
|       r2 = sqlite3ExprCodeTemp(pParse, pExpr->pRight, ®Free2);
 | |
|       op = (pExpr->op==TK_IS) ? TK_NE : TK_EQ;
 | |
|       codeCompare(pParse, pExpr->pLeft, pExpr->pRight, op,
 | |
|                   r1, r2, dest, SQLITE_NULLEQ);
 | |
|       VdbeCoverageIf(v, op==TK_EQ);
 | |
|       VdbeCoverageIf(v, op==TK_NE);
 | |
|       testcase( regFree1==0 );
 | |
|       testcase( regFree2==0 );
 | |
|       break;
 | |
|     }
 | |
|     case TK_ISNULL:
 | |
|     case TK_NOTNULL: {
 | |
|       r1 = sqlite3ExprCodeTemp(pParse, pExpr->pLeft, ®Free1);
 | |
|       sqlite3VdbeAddOp2(v, op, r1, dest);
 | |
|       testcase( op==TK_ISNULL );   VdbeCoverageIf(v, op==TK_ISNULL);
 | |
|       testcase( op==TK_NOTNULL );  VdbeCoverageIf(v, op==TK_NOTNULL);
 | |
|       testcase( regFree1==0 );
 | |
|       break;
 | |
|     }
 | |
|     case TK_BETWEEN: {
 | |
|       testcase( jumpIfNull==0 );
 | |
|       exprCodeBetween(pParse, pExpr, dest, 0, jumpIfNull);
 | |
|       break;
 | |
|     }
 | |
| #ifndef SQLITE_OMIT_SUBQUERY
 | |
|     case TK_IN: {
 | |
|       if( jumpIfNull ){
 | |
|         sqlite3ExprCodeIN(pParse, pExpr, dest, dest);
 | |
|       }else{
 | |
|         int destIfNull = sqlite3VdbeMakeLabel(v);
 | |
|         sqlite3ExprCodeIN(pParse, pExpr, dest, destIfNull);
 | |
|         sqlite3VdbeResolveLabel(v, destIfNull);
 | |
|       }
 | |
|       break;
 | |
|     }
 | |
| #endif
 | |
|     default: {
 | |
|       if( exprAlwaysFalse(pExpr) ){
 | |
|         sqlite3VdbeGoto(v, dest);
 | |
|       }else if( exprAlwaysTrue(pExpr) ){
 | |
|         /* no-op */
 | |
|       }else{
 | |
|         r1 = sqlite3ExprCodeTemp(pParse, pExpr, ®Free1);
 | |
|         sqlite3VdbeAddOp3(v, OP_IfNot, r1, dest, jumpIfNull!=0);
 | |
|         VdbeCoverage(v);
 | |
|         testcase( regFree1==0 );
 | |
|         testcase( jumpIfNull==0 );
 | |
|       }
 | |
|       break;
 | |
|     }
 | |
|   }
 | |
|   sqlite3ReleaseTempReg(pParse, regFree1);
 | |
|   sqlite3ReleaseTempReg(pParse, regFree2);
 | |
| }
 | |
| 
 | |
| /*
 | |
| ** Like sqlite3ExprIfFalse() except that a copy is made of pExpr before
 | |
| ** code generation, and that copy is deleted after code generation. This
 | |
| ** ensures that the original pExpr is unchanged.
 | |
| */
 | |
| void sqlite3ExprIfFalseDup(Parse *pParse, Expr *pExpr, int dest,int jumpIfNull){
 | |
|   sqlite3 *db = pParse->db;
 | |
|   Expr *pCopy = sqlite3ExprDup(db, pExpr, 0);
 | |
|   if( db->mallocFailed==0 ){
 | |
|     sqlite3ExprIfFalse(pParse, pCopy, dest, jumpIfNull);
 | |
|   }
 | |
|   sqlite3ExprDelete(db, pCopy);
 | |
| }
 | |
| 
 | |
| 
 | |
| /*
 | |
| ** Do a deep comparison of two expression trees.  Return 0 if the two
 | |
| ** expressions are completely identical.  Return 1 if they differ only
 | |
| ** by a COLLATE operator at the top level.  Return 2 if there are differences
 | |
| ** other than the top-level COLLATE operator.
 | |
| **
 | |
| ** If any subelement of pB has Expr.iTable==(-1) then it is allowed
 | |
| ** to compare equal to an equivalent element in pA with Expr.iTable==iTab.
 | |
| **
 | |
| ** The pA side might be using TK_REGISTER.  If that is the case and pB is
 | |
| ** not using TK_REGISTER but is otherwise equivalent, then still return 0.
 | |
| **
 | |
| ** Sometimes this routine will return 2 even if the two expressions
 | |
| ** really are equivalent.  If we cannot prove that the expressions are
 | |
| ** identical, we return 2 just to be safe.  So if this routine
 | |
| ** returns 2, then you do not really know for certain if the two
 | |
| ** expressions are the same.  But if you get a 0 or 1 return, then you
 | |
| ** can be sure the expressions are the same.  In the places where
 | |
| ** this routine is used, it does not hurt to get an extra 2 - that
 | |
| ** just might result in some slightly slower code.  But returning
 | |
| ** an incorrect 0 or 1 could lead to a malfunction.
 | |
| */
 | |
| int sqlite3ExprCompare(Expr *pA, Expr *pB, int iTab){
 | |
|   u32 combinedFlags;
 | |
|   if( pA==0 || pB==0 ){
 | |
|     return pB==pA ? 0 : 2;
 | |
|   }
 | |
|   combinedFlags = pA->flags | pB->flags;
 | |
|   if( combinedFlags & EP_IntValue ){
 | |
|     if( (pA->flags&pB->flags&EP_IntValue)!=0 && pA->u.iValue==pB->u.iValue ){
 | |
|       return 0;
 | |
|     }
 | |
|     return 2;
 | |
|   }
 | |
|   if( pA->op!=pB->op ){
 | |
|     if( pA->op==TK_COLLATE && sqlite3ExprCompare(pA->pLeft, pB, iTab)<2 ){
 | |
|       return 1;
 | |
|     }
 | |
|     if( pB->op==TK_COLLATE && sqlite3ExprCompare(pA, pB->pLeft, iTab)<2 ){
 | |
|       return 1;
 | |
|     }
 | |
|     return 2;
 | |
|   }
 | |
|   if( pA->op!=TK_COLUMN && pA->op!=TK_AGG_COLUMN && pA->u.zToken ){
 | |
|     if( pA->op==TK_FUNCTION ){
 | |
|       if( sqlite3StrICmp(pA->u.zToken,pB->u.zToken)!=0 ) return 2;
 | |
|     }else if( strcmp(pA->u.zToken,pB->u.zToken)!=0 ){
 | |
|       return pA->op==TK_COLLATE ? 1 : 2;
 | |
|     }
 | |
|   }
 | |
|   if( (pA->flags & EP_Distinct)!=(pB->flags & EP_Distinct) ) return 2;
 | |
|   if( ALWAYS((combinedFlags & EP_TokenOnly)==0) ){
 | |
|     if( combinedFlags & EP_xIsSelect ) return 2;
 | |
|     if( sqlite3ExprCompare(pA->pLeft, pB->pLeft, iTab) ) return 2;
 | |
|     if( sqlite3ExprCompare(pA->pRight, pB->pRight, iTab) ) return 2;
 | |
|     if( sqlite3ExprListCompare(pA->x.pList, pB->x.pList, iTab) ) return 2;
 | |
|     if( ALWAYS((combinedFlags & EP_Reduced)==0) && pA->op!=TK_STRING ){
 | |
|       if( pA->iColumn!=pB->iColumn ) return 2;
 | |
|       if( pA->iTable!=pB->iTable 
 | |
|        && (pA->iTable!=iTab || NEVER(pB->iTable>=0)) ) return 2;
 | |
|     }
 | |
|   }
 | |
|   return 0;
 | |
| }
 | |
| 
 | |
| /*
 | |
| ** Compare two ExprList objects.  Return 0 if they are identical and 
 | |
| ** non-zero if they differ in any way.
 | |
| **
 | |
| ** If any subelement of pB has Expr.iTable==(-1) then it is allowed
 | |
| ** to compare equal to an equivalent element in pA with Expr.iTable==iTab.
 | |
| **
 | |
| ** This routine might return non-zero for equivalent ExprLists.  The
 | |
| ** only consequence will be disabled optimizations.  But this routine
 | |
| ** must never return 0 if the two ExprList objects are different, or
 | |
| ** a malfunction will result.
 | |
| **
 | |
| ** Two NULL pointers are considered to be the same.  But a NULL pointer
 | |
| ** always differs from a non-NULL pointer.
 | |
| */
 | |
| int sqlite3ExprListCompare(ExprList *pA, ExprList *pB, int iTab){
 | |
|   int i;
 | |
|   if( pA==0 && pB==0 ) return 0;
 | |
|   if( pA==0 || pB==0 ) return 1;
 | |
|   if( pA->nExpr!=pB->nExpr ) return 1;
 | |
|   for(i=0; i<pA->nExpr; i++){
 | |
|     Expr *pExprA = pA->a[i].pExpr;
 | |
|     Expr *pExprB = pB->a[i].pExpr;
 | |
|     if( pA->a[i].sortOrder!=pB->a[i].sortOrder ) return 1;
 | |
|     if( sqlite3ExprCompare(pExprA, pExprB, iTab) ) return 1;
 | |
|   }
 | |
|   return 0;
 | |
| }
 | |
| 
 | |
| /*
 | |
| ** Return true if we can prove the pE2 will always be true if pE1 is
 | |
| ** true.  Return false if we cannot complete the proof or if pE2 might
 | |
| ** be false.  Examples:
 | |
| **
 | |
| **     pE1: x==5       pE2: x==5             Result: true
 | |
| **     pE1: x>0        pE2: x==5             Result: false
 | |
| **     pE1: x=21       pE2: x=21 OR y=43     Result: true
 | |
| **     pE1: x!=123     pE2: x IS NOT NULL    Result: true
 | |
| **     pE1: x!=?1      pE2: x IS NOT NULL    Result: true
 | |
| **     pE1: x IS NULL  pE2: x IS NOT NULL    Result: false
 | |
| **     pE1: x IS ?2    pE2: x IS NOT NULL    Reuslt: false
 | |
| **
 | |
| ** When comparing TK_COLUMN nodes between pE1 and pE2, if pE2 has
 | |
| ** Expr.iTable<0 then assume a table number given by iTab.
 | |
| **
 | |
| ** When in doubt, return false.  Returning true might give a performance
 | |
| ** improvement.  Returning false might cause a performance reduction, but
 | |
| ** it will always give the correct answer and is hence always safe.
 | |
| */
 | |
| int sqlite3ExprImpliesExpr(Expr *pE1, Expr *pE2, int iTab){
 | |
|   if( sqlite3ExprCompare(pE1, pE2, iTab)==0 ){
 | |
|     return 1;
 | |
|   }
 | |
|   if( pE2->op==TK_OR
 | |
|    && (sqlite3ExprImpliesExpr(pE1, pE2->pLeft, iTab)
 | |
|              || sqlite3ExprImpliesExpr(pE1, pE2->pRight, iTab) )
 | |
|   ){
 | |
|     return 1;
 | |
|   }
 | |
|   if( pE2->op==TK_NOTNULL
 | |
|    && sqlite3ExprCompare(pE1->pLeft, pE2->pLeft, iTab)==0
 | |
|    && (pE1->op!=TK_ISNULL && pE1->op!=TK_IS)
 | |
|   ){
 | |
|     return 1;
 | |
|   }
 | |
|   return 0;
 | |
| }
 | |
| 
 | |
| /*
 | |
| ** An instance of the following structure is used by the tree walker
 | |
| ** to count references to table columns in the arguments of an 
 | |
| ** aggregate function, in order to implement the
 | |
| ** sqlite3FunctionThisSrc() routine.
 | |
| */
 | |
| struct SrcCount {
 | |
|   SrcList *pSrc;   /* One particular FROM clause in a nested query */
 | |
|   int nThis;       /* Number of references to columns in pSrcList */
 | |
|   int nOther;      /* Number of references to columns in other FROM clauses */
 | |
| };
 | |
| 
 | |
| /*
 | |
| ** Count the number of references to columns.
 | |
| */
 | |
| static int exprSrcCount(Walker *pWalker, Expr *pExpr){
 | |
|   /* The NEVER() on the second term is because sqlite3FunctionUsesThisSrc()
 | |
|   ** is always called before sqlite3ExprAnalyzeAggregates() and so the
 | |
|   ** TK_COLUMNs have not yet been converted into TK_AGG_COLUMN.  If
 | |
|   ** sqlite3FunctionUsesThisSrc() is used differently in the future, the
 | |
|   ** NEVER() will need to be removed. */
 | |
|   if( pExpr->op==TK_COLUMN || NEVER(pExpr->op==TK_AGG_COLUMN) ){
 | |
|     int i;
 | |
|     struct SrcCount *p = pWalker->u.pSrcCount;
 | |
|     SrcList *pSrc = p->pSrc;
 | |
|     int nSrc = pSrc ? pSrc->nSrc : 0;
 | |
|     for(i=0; i<nSrc; i++){
 | |
|       if( pExpr->iTable==pSrc->a[i].iCursor ) break;
 | |
|     }
 | |
|     if( i<nSrc ){
 | |
|       p->nThis++;
 | |
|     }else{
 | |
|       p->nOther++;
 | |
|     }
 | |
|   }
 | |
|   return WRC_Continue;
 | |
| }
 | |
| 
 | |
| /*
 | |
| ** Determine if any of the arguments to the pExpr Function reference
 | |
| ** pSrcList.  Return true if they do.  Also return true if the function
 | |
| ** has no arguments or has only constant arguments.  Return false if pExpr
 | |
| ** references columns but not columns of tables found in pSrcList.
 | |
| */
 | |
| int sqlite3FunctionUsesThisSrc(Expr *pExpr, SrcList *pSrcList){
 | |
|   Walker w;
 | |
|   struct SrcCount cnt;
 | |
|   assert( pExpr->op==TK_AGG_FUNCTION );
 | |
|   memset(&w, 0, sizeof(w));
 | |
|   w.xExprCallback = exprSrcCount;
 | |
|   w.u.pSrcCount = &cnt;
 | |
|   cnt.pSrc = pSrcList;
 | |
|   cnt.nThis = 0;
 | |
|   cnt.nOther = 0;
 | |
|   sqlite3WalkExprList(&w, pExpr->x.pList);
 | |
|   return cnt.nThis>0 || cnt.nOther==0;
 | |
| }
 | |
| 
 | |
| /*
 | |
| ** Add a new element to the pAggInfo->aCol[] array.  Return the index of
 | |
| ** the new element.  Return a negative number if malloc fails.
 | |
| */
 | |
| static int addAggInfoColumn(sqlite3 *db, AggInfo *pInfo){
 | |
|   int i;
 | |
|   pInfo->aCol = sqlite3ArrayAllocate(
 | |
|        db,
 | |
|        pInfo->aCol,
 | |
|        sizeof(pInfo->aCol[0]),
 | |
|        &pInfo->nColumn,
 | |
|        &i
 | |
|   );
 | |
|   return i;
 | |
| }    
 | |
| 
 | |
| /*
 | |
| ** Add a new element to the pAggInfo->aFunc[] array.  Return the index of
 | |
| ** the new element.  Return a negative number if malloc fails.
 | |
| */
 | |
| static int addAggInfoFunc(sqlite3 *db, AggInfo *pInfo){
 | |
|   int i;
 | |
|   pInfo->aFunc = sqlite3ArrayAllocate(
 | |
|        db, 
 | |
|        pInfo->aFunc,
 | |
|        sizeof(pInfo->aFunc[0]),
 | |
|        &pInfo->nFunc,
 | |
|        &i
 | |
|   );
 | |
|   return i;
 | |
| }    
 | |
| 
 | |
| /*
 | |
| ** This is the xExprCallback for a tree walker.  It is used to
 | |
| ** implement sqlite3ExprAnalyzeAggregates().  See sqlite3ExprAnalyzeAggregates
 | |
| ** for additional information.
 | |
| */
 | |
| static int analyzeAggregate(Walker *pWalker, Expr *pExpr){
 | |
|   int i;
 | |
|   NameContext *pNC = pWalker->u.pNC;
 | |
|   Parse *pParse = pNC->pParse;
 | |
|   SrcList *pSrcList = pNC->pSrcList;
 | |
|   AggInfo *pAggInfo = pNC->pAggInfo;
 | |
| 
 | |
|   switch( pExpr->op ){
 | |
|     case TK_AGG_COLUMN:
 | |
|     case TK_COLUMN: {
 | |
|       testcase( pExpr->op==TK_AGG_COLUMN );
 | |
|       testcase( pExpr->op==TK_COLUMN );
 | |
|       /* Check to see if the column is in one of the tables in the FROM
 | |
|       ** clause of the aggregate query */
 | |
|       if( ALWAYS(pSrcList!=0) ){
 | |
|         struct SrcList_item *pItem = pSrcList->a;
 | |
|         for(i=0; i<pSrcList->nSrc; i++, pItem++){
 | |
|           struct AggInfo_col *pCol;
 | |
|           assert( !ExprHasProperty(pExpr, EP_TokenOnly|EP_Reduced) );
 | |
|           if( pExpr->iTable==pItem->iCursor ){
 | |
|             /* If we reach this point, it means that pExpr refers to a table
 | |
|             ** that is in the FROM clause of the aggregate query.  
 | |
|             **
 | |
|             ** Make an entry for the column in pAggInfo->aCol[] if there
 | |
|             ** is not an entry there already.
 | |
|             */
 | |
|             int k;
 | |
|             pCol = pAggInfo->aCol;
 | |
|             for(k=0; k<pAggInfo->nColumn; k++, pCol++){
 | |
|               if( pCol->iTable==pExpr->iTable &&
 | |
|                   pCol->iColumn==pExpr->iColumn ){
 | |
|                 break;
 | |
|               }
 | |
|             }
 | |
|             if( (k>=pAggInfo->nColumn)
 | |
|              && (k = addAggInfoColumn(pParse->db, pAggInfo))>=0 
 | |
|             ){
 | |
|               pCol = &pAggInfo->aCol[k];
 | |
|               pCol->pTab = pExpr->pTab;
 | |
|               pCol->iTable = pExpr->iTable;
 | |
|               pCol->iColumn = pExpr->iColumn;
 | |
|               pCol->iMem = ++pParse->nMem;
 | |
|               pCol->iSorterColumn = -1;
 | |
|               pCol->pExpr = pExpr;
 | |
|               if( pAggInfo->pGroupBy ){
 | |
|                 int j, n;
 | |
|                 ExprList *pGB = pAggInfo->pGroupBy;
 | |
|                 struct ExprList_item *pTerm = pGB->a;
 | |
|                 n = pGB->nExpr;
 | |
|                 for(j=0; j<n; j++, pTerm++){
 | |
|                   Expr *pE = pTerm->pExpr;
 | |
|                   if( pE->op==TK_COLUMN && pE->iTable==pExpr->iTable &&
 | |
|                       pE->iColumn==pExpr->iColumn ){
 | |
|                     pCol->iSorterColumn = j;
 | |
|                     break;
 | |
|                   }
 | |
|                 }
 | |
|               }
 | |
|               if( pCol->iSorterColumn<0 ){
 | |
|                 pCol->iSorterColumn = pAggInfo->nSortingColumn++;
 | |
|               }
 | |
|             }
 | |
|             /* There is now an entry for pExpr in pAggInfo->aCol[] (either
 | |
|             ** because it was there before or because we just created it).
 | |
|             ** Convert the pExpr to be a TK_AGG_COLUMN referring to that
 | |
|             ** pAggInfo->aCol[] entry.
 | |
|             */
 | |
|             ExprSetVVAProperty(pExpr, EP_NoReduce);
 | |
|             pExpr->pAggInfo = pAggInfo;
 | |
|             pExpr->op = TK_AGG_COLUMN;
 | |
|             pExpr->iAgg = (i16)k;
 | |
|             break;
 | |
|           } /* endif pExpr->iTable==pItem->iCursor */
 | |
|         } /* end loop over pSrcList */
 | |
|       }
 | |
|       return WRC_Prune;
 | |
|     }
 | |
|     case TK_AGG_FUNCTION: {
 | |
|       if( (pNC->ncFlags & NC_InAggFunc)==0
 | |
|        && pWalker->walkerDepth==pExpr->op2
 | |
|       ){
 | |
|         /* Check to see if pExpr is a duplicate of another aggregate 
 | |
|         ** function that is already in the pAggInfo structure
 | |
|         */
 | |
|         struct AggInfo_func *pItem = pAggInfo->aFunc;
 | |
|         for(i=0; i<pAggInfo->nFunc; i++, pItem++){
 | |
|           if( sqlite3ExprCompare(pItem->pExpr, pExpr, -1)==0 ){
 | |
|             break;
 | |
|           }
 | |
|         }
 | |
|         if( i>=pAggInfo->nFunc ){
 | |
|           /* pExpr is original.  Make a new entry in pAggInfo->aFunc[]
 | |
|           */
 | |
|           u8 enc = ENC(pParse->db);
 | |
|           i = addAggInfoFunc(pParse->db, pAggInfo);
 | |
|           if( i>=0 ){
 | |
|             assert( !ExprHasProperty(pExpr, EP_xIsSelect) );
 | |
|             pItem = &pAggInfo->aFunc[i];
 | |
|             pItem->pExpr = pExpr;
 | |
|             pItem->iMem = ++pParse->nMem;
 | |
|             assert( !ExprHasProperty(pExpr, EP_IntValue) );
 | |
|             pItem->pFunc = sqlite3FindFunction(pParse->db,
 | |
|                    pExpr->u.zToken, sqlite3Strlen30(pExpr->u.zToken),
 | |
|                    pExpr->x.pList ? pExpr->x.pList->nExpr : 0, enc, 0);
 | |
|             if( pExpr->flags & EP_Distinct ){
 | |
|               pItem->iDistinct = pParse->nTab++;
 | |
|             }else{
 | |
|               pItem->iDistinct = -1;
 | |
|             }
 | |
|           }
 | |
|         }
 | |
|         /* Make pExpr point to the appropriate pAggInfo->aFunc[] entry
 | |
|         */
 | |
|         assert( !ExprHasProperty(pExpr, EP_TokenOnly|EP_Reduced) );
 | |
|         ExprSetVVAProperty(pExpr, EP_NoReduce);
 | |
|         pExpr->iAgg = (i16)i;
 | |
|         pExpr->pAggInfo = pAggInfo;
 | |
|         return WRC_Prune;
 | |
|       }else{
 | |
|         return WRC_Continue;
 | |
|       }
 | |
|     }
 | |
|   }
 | |
|   return WRC_Continue;
 | |
| }
 | |
| static int analyzeAggregatesInSelect(Walker *pWalker, Select *pSelect){
 | |
|   UNUSED_PARAMETER(pWalker);
 | |
|   UNUSED_PARAMETER(pSelect);
 | |
|   return WRC_Continue;
 | |
| }
 | |
| 
 | |
| /*
 | |
| ** Analyze the pExpr expression looking for aggregate functions and
 | |
| ** for variables that need to be added to AggInfo object that pNC->pAggInfo
 | |
| ** points to.  Additional entries are made on the AggInfo object as
 | |
| ** necessary.
 | |
| **
 | |
| ** This routine should only be called after the expression has been
 | |
| ** analyzed by sqlite3ResolveExprNames().
 | |
| */
 | |
| void sqlite3ExprAnalyzeAggregates(NameContext *pNC, Expr *pExpr){
 | |
|   Walker w;
 | |
|   memset(&w, 0, sizeof(w));
 | |
|   w.xExprCallback = analyzeAggregate;
 | |
|   w.xSelectCallback = analyzeAggregatesInSelect;
 | |
|   w.u.pNC = pNC;
 | |
|   assert( pNC->pSrcList!=0 );
 | |
|   sqlite3WalkExpr(&w, pExpr);
 | |
| }
 | |
| 
 | |
| /*
 | |
| ** Call sqlite3ExprAnalyzeAggregates() for every expression in an
 | |
| ** expression list.  Return the number of errors.
 | |
| **
 | |
| ** If an error is found, the analysis is cut short.
 | |
| */
 | |
| void sqlite3ExprAnalyzeAggList(NameContext *pNC, ExprList *pList){
 | |
|   struct ExprList_item *pItem;
 | |
|   int i;
 | |
|   if( pList ){
 | |
|     for(pItem=pList->a, i=0; i<pList->nExpr; i++, pItem++){
 | |
|       sqlite3ExprAnalyzeAggregates(pNC, pItem->pExpr);
 | |
|     }
 | |
|   }
 | |
| }
 | |
| 
 | |
| /*
 | |
| ** Allocate a single new register for use to hold some intermediate result.
 | |
| */
 | |
| int sqlite3GetTempReg(Parse *pParse){
 | |
|   if( pParse->nTempReg==0 ){
 | |
|     return ++pParse->nMem;
 | |
|   }
 | |
|   return pParse->aTempReg[--pParse->nTempReg];
 | |
| }
 | |
| 
 | |
| /*
 | |
| ** Deallocate a register, making available for reuse for some other
 | |
| ** purpose.
 | |
| **
 | |
| ** If a register is currently being used by the column cache, then
 | |
| ** the deallocation is deferred until the column cache line that uses
 | |
| ** the register becomes stale.
 | |
| */
 | |
| void sqlite3ReleaseTempReg(Parse *pParse, int iReg){
 | |
|   if( iReg && pParse->nTempReg<ArraySize(pParse->aTempReg) ){
 | |
|     int i;
 | |
|     struct yColCache *p;
 | |
|     for(i=0, p=pParse->aColCache; i<SQLITE_N_COLCACHE; i++, p++){
 | |
|       if( p->iReg==iReg ){
 | |
|         p->tempReg = 1;
 | |
|         return;
 | |
|       }
 | |
|     }
 | |
|     pParse->aTempReg[pParse->nTempReg++] = iReg;
 | |
|   }
 | |
| }
 | |
| 
 | |
| /*
 | |
| ** Allocate or deallocate a block of nReg consecutive registers
 | |
| */
 | |
| int sqlite3GetTempRange(Parse *pParse, int nReg){
 | |
|   int i, n;
 | |
|   i = pParse->iRangeReg;
 | |
|   n = pParse->nRangeReg;
 | |
|   if( nReg<=n ){
 | |
|     assert( !usedAsColumnCache(pParse, i, i+n-1) );
 | |
|     pParse->iRangeReg += nReg;
 | |
|     pParse->nRangeReg -= nReg;
 | |
|   }else{
 | |
|     i = pParse->nMem+1;
 | |
|     pParse->nMem += nReg;
 | |
|   }
 | |
|   return i;
 | |
| }
 | |
| void sqlite3ReleaseTempRange(Parse *pParse, int iReg, int nReg){
 | |
|   sqlite3ExprCacheRemove(pParse, iReg, nReg);
 | |
|   if( nReg>pParse->nRangeReg ){
 | |
|     pParse->nRangeReg = nReg;
 | |
|     pParse->iRangeReg = iReg;
 | |
|   }
 | |
| }
 | |
| 
 | |
| /*
 | |
| ** Mark all temporary registers as being unavailable for reuse.
 | |
| */
 | |
| void sqlite3ClearTempRegCache(Parse *pParse){
 | |
|   pParse->nTempReg = 0;
 | |
|   pParse->nRangeReg = 0;
 | |
| }
 | 
