int reg = 0;
#ifndef SQLITE_OMIT_SUBQUERY
if( pExpr->op==TK_SELECT ){
- reg = sqlite3CodeSubselect(pParse, pExpr, 0, 0);
+ reg = sqlite3CodeSubselect(pParse, pExpr);
}
#endif
return reg;
}else if( prRhsHasNull ){
*prRhsHasNull = rMayHaveNull = ++pParse->nMem;
}
- sqlite3CodeSubselect(pParse, pX, rMayHaveNull, eType==IN_INDEX_ROWID);
+ assert( pX->op==TK_IN );
+ sqlite3CodeRhsOfIN(pParse, pX, eType==IN_INDEX_ROWID);
+ if( rMayHaveNull ){
+ sqlite3SetHasNullFlag(v, pX->iTable, rMayHaveNull);
+ }
pParse->nQueryLoop = savedNQueryLoop;
}else{
pX->iTable = iTab;
}
}
+#ifndef SQLITE_OMIT_SUBQUERY
/*
-** Generate code for scalar subqueries used as a subquery expression, EXISTS,
-** or IN operators. Examples:
+** Generate code that will construct an ephemeral table containing all terms
+** in the RHS of an IN operator. The IN operator can be in either of two
+** forms:
**
-** (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 a multi-column SELECT, the result is stored in a contiguous
-** array of registers and the return value is the register of the left-most
-** result column. Return 0 for IN operators or if an error occurs.
+** The pExpr parameter is the IN operator.
+**
+** If parameter isRowid is non-zero, then LHS of the IN operator is guaranteed
+** to be a non-null integer. In this case, the ephemeral table can be an
+** table B-Tree that keyed by only integers. The more general cases uses
+** an index B-Tree which can have arbitrary keys, but is slower to both
+** read and write.
+**
+** If the LHS expression ("x" in the examples) 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.
*/
-#ifndef SQLITE_OMIT_SUBQUERY
-int sqlite3CodeSubselect(
+void sqlite3CodeRhsOfIN(
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 */
+ Expr *pExpr, /* The IN operator */
+ int isRowid /* If true, LHS 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;
+ int jmpIfDynamic = -1; /* One-time test address */
+ int addr; /* Address of OP_OpenEphemeral instruction */
+ Expr *pLeft; /* the LHS of the IN operator */
+ KeyInfo *pKeyInfo = 0; /* Key information */
+ int nVal; /* Size of vector pLeft */
+ Vdbe *v; /* The prepared statement under construction */
+
+ v = sqlite3GetVdbe(pParse);
+ assert( v!=0 );
- /* The evaluation of the IN/EXISTS/SELECT must be repeated every time it
+ /* The evaluation of the RHS of IN operator must be repeated every time it
** is encountered if any of the following is true:
**
** * The right-hand side is a correlated subquery
jmpIfDynamic = sqlite3VdbeAddOp0(v, OP_Once); VdbeCoverage(v);
}
- switch( pExpr->op ){
- case TK_IN: {
- int addr; /* Address of OP_OpenEphemeral instruction */
- Expr *pLeft = pExpr->pLeft; /* the LHS of the IN operator */
- KeyInfo *pKeyInfo = 0; /* Key information */
- int nVal; /* Size of vector pLeft */
-
- nVal = sqlite3ExprVectorSize(pLeft);
- assert( !isRowid || nVal==1 );
-
- /* 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 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?0:nVal));
- pKeyInfo = isRowid ? 0 : sqlite3KeyInfoAlloc(pParse->db, nVal, 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;
- ExprList *pEList = pSelect->pEList;
-
- ExplainQueryPlan((pParse, 1, "%sLIST SUBQUERY",
- jmpIfDynamic>=0?"":"CORRELATED "
- ));
- assert( !isRowid );
- /* If the LHS and RHS of the IN operator do not match, that
- ** error will have been caught long before we reach this point. */
- if( ALWAYS(pEList->nExpr==nVal) ){
- SelectDest dest;
- int i;
- sqlite3SelectDestInit(&dest, SRT_Set, pExpr->iTable);
- dest.zAffSdst = exprINAffinity(pParse, pExpr);
- pSelect->iLimit = 0;
- testcase( pSelect->selFlags & SF_Distinct );
- testcase( pKeyInfo==0 ); /* Caused by OOM in sqlite3KeyInfoAlloc() */
- if( sqlite3Select(pParse, pSelect, &dest) ){
- sqlite3DbFree(pParse->db, dest.zAffSdst);
- sqlite3KeyInfoUnref(pKeyInfo);
- return 0;
- }
- sqlite3DbFree(pParse->db, dest.zAffSdst);
- assert( pKeyInfo!=0 ); /* OOM will cause exit after sqlite3Select() */
- assert( pEList!=0 );
- assert( pEList->nExpr>0 );
- assert( sqlite3KeyInfoIsWriteable(pKeyInfo) );
- for(i=0; i<nVal; i++){
- Expr *p = sqlite3VectorFieldSubexpr(pLeft, i);
- pKeyInfo->aColl[i] = sqlite3BinaryCompareCollSeq(
- pParse, p, pEList->a[i].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.
- */
- char affinity; /* Affinity of the LHS of the IN */
- int i;
- ExprList *pList = pExpr->x.pList;
- struct ExprList_item *pItem;
- int r1, r2, r3;
- affinity = sqlite3ExprAffinity(pLeft);
- if( !affinity ){
- affinity = SQLITE_AFF_BLOB;
- }
- if( pKeyInfo ){
- assert( sqlite3KeyInfoIsWriteable(pKeyInfo) );
- pKeyInfo->aColl[0] = sqlite3ExprCollSeq(pParse, pExpr->pLeft);
- }
+ /* Check to see if this is a vector IN operator */
+ pLeft = pExpr->pLeft;
+ nVal = sqlite3ExprVectorSize(pLeft);
+ assert( !isRowid || nVal==1 );
- /* Loop through each expression in <exprlist>. */
- r1 = sqlite3GetTempReg(pParse);
- r2 = sqlite3GetTempReg(pParse);
- if( isRowid ) sqlite3VdbeAddOp4(v, OP_Blob, 0, r2, 0, "", P4_STATIC);
- 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;
- }
+ /* Construct the ephemeral table that will contain the content of
+ ** RHS of the IN operator.
+ */
+ pExpr->iTable = pParse->nTab++;
+ addr = sqlite3VdbeAddOp2(v, OP_OpenEphemeral,
+ pExpr->iTable, (isRowid?0:nVal));
+ pKeyInfo = isRowid ? 0 : sqlite3KeyInfoAlloc(pParse->db, nVal, 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);
- sqlite3VdbeAddOp4Int(v, OP_IdxInsert, pExpr->iTable, r2, r3, 1);
- }
- }
- }
- sqlite3ReleaseTempReg(pParse, r1);
- sqlite3ReleaseTempReg(pParse, r2);
+ 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;
+ ExprList *pEList = pSelect->pEList;
+
+ ExplainQueryPlan((pParse, 1, "%sLIST SUBQUERY",
+ jmpIfDynamic>=0?"":"CORRELATED "
+ ));
+ assert( !isRowid );
+ /* If the LHS and RHS of the IN operator do not match, that
+ ** error will have been caught long before we reach this point. */
+ if( ALWAYS(pEList->nExpr==nVal) ){
+ SelectDest dest;
+ int i;
+ sqlite3SelectDestInit(&dest, SRT_Set, pExpr->iTable);
+ dest.zAffSdst = exprINAffinity(pParse, pExpr);
+ pSelect->iLimit = 0;
+ testcase( pSelect->selFlags & SF_Distinct );
+ testcase( pKeyInfo==0 ); /* Caused by OOM in sqlite3KeyInfoAlloc() */
+ if( sqlite3Select(pParse, pSelect, &dest) ){
+ sqlite3DbFree(pParse->db, dest.zAffSdst);
+ sqlite3KeyInfoUnref(pKeyInfo);
+ return;
}
- if( pKeyInfo ){
- sqlite3VdbeChangeP4(v, addr, (void *)pKeyInfo, P4_KEYINFO);
+ sqlite3DbFree(pParse->db, dest.zAffSdst);
+ assert( pKeyInfo!=0 ); /* OOM will cause exit after sqlite3Select() */
+ assert( pEList!=0 );
+ assert( pEList->nExpr>0 );
+ assert( sqlite3KeyInfoIsWriteable(pKeyInfo) );
+ for(i=0; i<nVal; i++){
+ Expr *p = sqlite3VectorFieldSubexpr(pLeft, i);
+ pKeyInfo->aColl[i] = sqlite3BinaryCompareCollSeq(
+ pParse, p, pEList->a[i].pExpr
+ );
}
- break;
+ }
+ }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.
+ */
+ char affinity; /* Affinity of the LHS of the IN */
+ int i;
+ ExprList *pList = pExpr->x.pList;
+ struct ExprList_item *pItem;
+ int r1, r2, r3;
+ affinity = sqlite3ExprAffinity(pLeft);
+ if( !affinity ){
+ affinity = SQLITE_AFF_BLOB;
+ }
+ if( pKeyInfo ){
+ assert( sqlite3KeyInfoIsWriteable(pKeyInfo) );
+ pKeyInfo->aColl[0] = sqlite3ExprCollSeq(pParse, pExpr->pLeft);
}
- case TK_EXISTS:
- case TK_SELECT:
- default: {
- /* Case 3: (SELECT ... FROM ...)
- ** or: EXISTS(SELECT ... FROM ...)
- **
- ** For a SELECT, generate code to put the values for all columns of
- ** the first row into an array of registers and return the index of
- ** the first register.
- **
- ** If this is an EXISTS, write an integer 0 (not exists) or 1 (exists)
- ** into a register and return that register number.
- **
- ** In both cases, the query is augmented with "LIMIT 1". Any
- ** preexisting limit is discarded in place of the new LIMIT 1.
+ /* Loop through each expression in <exprlist>. */
+ r1 = sqlite3GetTempReg(pParse);
+ r2 = sqlite3GetTempReg(pParse);
+ if( isRowid ) sqlite3VdbeAddOp4(v, OP_Blob, 0, r2, 0, "", P4_STATIC);
+ 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.
*/
- Select *pSel; /* SELECT statement to encode */
- SelectDest dest; /* How to deal with SELECT result */
- int nReg; /* Registers to allocate */
- Expr *pLimit; /* New limit expression */
-
- 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;
- ExplainQueryPlan((pParse, 1, "%sSCALAR SUBQUERY",
- jmpIfDynamic>=0?"":"CORRELATED "));
- nReg = pExpr->op==TK_SELECT ? pSel->pEList->nExpr : 1;
- sqlite3SelectDestInit(&dest, 0, pParse->nMem+1);
- pParse->nMem += nReg;
- if( pExpr->op==TK_SELECT ){
- dest.eDest = SRT_Mem;
- dest.iSdst = dest.iSDParm;
- dest.nSdst = nReg;
- sqlite3VdbeAddOp3(v, OP_Null, 0, dest.iSDParm, dest.iSDParm+nReg-1);
- VdbeComment((v, "Init subquery result"));
- }else{
- dest.eDest = SRT_Exists;
- sqlite3VdbeAddOp2(v, OP_Integer, 0, dest.iSDParm);
- VdbeComment((v, "Init EXISTS result"));
+ if( jmpIfDynamic>=0 && !sqlite3ExprIsConstant(pE2) ){
+ sqlite3VdbeChangeToNoop(v, jmpIfDynamic);
+ jmpIfDynamic = -1;
}
- pLimit = sqlite3ExprAlloc(pParse->db, TK_INTEGER,&sqlite3IntTokens[1], 0);
- if( pSel->pLimit ){
- sqlite3ExprDelete(pParse->db, pSel->pLimit->pLeft);
- pSel->pLimit->pLeft = pLimit;
+
+ /* Evaluate the expression and insert it into the temp table */
+ if( isRowid && sqlite3ExprIsInteger(pE2, &iValToIns) ){
+ sqlite3VdbeAddOp3(v, OP_InsertInt, pExpr->iTable, r2, iValToIns);
}else{
- pSel->pLimit = sqlite3PExpr(pParse, TK_LIMIT, pLimit, 0);
- }
- pSel->iLimit = 0;
- if( sqlite3Select(pParse, pSel, &dest) ){
- return 0;
+ 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);
+ sqlite3VdbeAddOp4Int(v, OP_IdxInsert, pExpr->iTable, r2, r3, 1);
+ }
}
- rReg = dest.iSDParm;
- ExprSetVVAProperty(pExpr, EP_NoReduce);
- break;
}
+ sqlite3ReleaseTempReg(pParse, r1);
+ sqlite3ReleaseTempReg(pParse, r2);
+ }
+ if( pKeyInfo ){
+ sqlite3VdbeChangeP4(v, addr, (void *)pKeyInfo, P4_KEYINFO);
+ }
+ if( jmpIfDynamic>=0 ){
+ sqlite3VdbeJumpHere(v, jmpIfDynamic);
}
+}
+#endif /* SQLITE_OMIT_SUBQUERY */
- if( rHasNullFlag ){
- sqlite3SetHasNullFlag(v, pExpr->iTable, rHasNullFlag);
+/*
+** Generate code for scalar subqueries used as a subquery expression
+** or EXISTS operator:
+**
+** (SELECT a FROM b) -- subquery
+** EXISTS (SELECT a FROM b) -- EXISTS subquery
+**
+** The pExpr parameter is the SELECT or EXISTS operator to be coded.
+**
+** The register that holds the result. For a multi-column SELECT,
+** the result is stored in a contiguous array of registers and the
+** return value is the register of the left-most result column.
+** Return 0 if an error occurs.
+*/
+#ifndef SQLITE_OMIT_SUBQUERY
+int sqlite3CodeSubselect(Parse *pParse, Expr *pExpr){
+ int jmpIfDynamic = -1; /* One-time test address */
+ int rReg = 0; /* Register storing resulting */
+ Select *pSel; /* SELECT statement to encode */
+ SelectDest dest; /* How to deal with SELECT result */
+ int nReg; /* Registers to allocate */
+ Expr *pLimit; /* New limit expression */
+ Vdbe *v = sqlite3GetVdbe(pParse);
+ assert( v!=0 );
+
+ /* The evaluation of the EXISTS/SELECT must be repeated 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 = sqlite3VdbeAddOp0(v, OP_Once); VdbeCoverage(v);
+ }
+
+ /* For a SELECT, generate code to put the values for all columns of
+ ** the first row into an array of registers and return the index of
+ ** the first register.
+ **
+ ** If this is an EXISTS, write an integer 0 (not exists) or 1 (exists)
+ ** into a register and return that register number.
+ **
+ ** In both cases, the query is augmented with "LIMIT 1". Any
+ ** preexisting limit is discarded in place of the new LIMIT 1.
+ */
+ 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;
+ ExplainQueryPlan((pParse, 1, "%sSCALAR SUBQUERY",
+ jmpIfDynamic>=0?"":"CORRELATED "));
+ nReg = pExpr->op==TK_SELECT ? pSel->pEList->nExpr : 1;
+ sqlite3SelectDestInit(&dest, 0, pParse->nMem+1);
+ pParse->nMem += nReg;
+ if( pExpr->op==TK_SELECT ){
+ dest.eDest = SRT_Mem;
+ dest.iSdst = dest.iSDParm;
+ dest.nSdst = nReg;
+ sqlite3VdbeAddOp3(v, OP_Null, 0, dest.iSDParm, dest.iSDParm+nReg-1);
+ VdbeComment((v, "Init subquery result"));
+ }else{
+ dest.eDest = SRT_Exists;
+ sqlite3VdbeAddOp2(v, OP_Integer, 0, dest.iSDParm);
+ VdbeComment((v, "Init EXISTS result"));
+ }
+ pLimit = sqlite3ExprAlloc(pParse->db, TK_INTEGER,&sqlite3IntTokens[1], 0);
+ if( pSel->pLimit ){
+ sqlite3ExprDelete(pParse->db, pSel->pLimit->pLeft);
+ pSel->pLimit->pLeft = pLimit;
+ }else{
+ pSel->pLimit = sqlite3PExpr(pParse, TK_LIMIT, pLimit, 0);
+ }
+ pSel->iLimit = 0;
+ if( sqlite3Select(pParse, pSel, &dest) ){
+ return 0;
}
+ rReg = dest.iSDParm;
+ ExprSetVVAProperty(pExpr, EP_NoReduce);
if( jmpIfDynamic>=0 ){
sqlite3VdbeJumpHere(v, jmpIfDynamic);
#if SQLITE_OMIT_SUBQUERY
iResult = 0;
#else
- iResult = sqlite3CodeSubselect(pParse, p, 0, 0);
+ iResult = sqlite3CodeSubselect(pParse, p);
#endif
}else{
int i;
if( op==TK_SELECT && (nCol = pExpr->x.pSelect->pEList->nExpr)!=1 ){
sqlite3SubselectError(pParse, nCol, 1);
}else{
- return sqlite3CodeSubselect(pParse, pExpr, 0, 0);
+ return sqlite3CodeSubselect(pParse, pExpr);
}
break;
}
case TK_SELECT_COLUMN: {
int n;
if( pExpr->pLeft->iTable==0 ){
- pExpr->pLeft->iTable = sqlite3CodeSubselect(pParse, pExpr->pLeft, 0, 0);
+ pExpr->pLeft->iTable = sqlite3CodeSubselect(pParse, pExpr->pLeft);
}
assert( pExpr->iTable==0 || pExpr->pLeft->op==TK_SELECT );
if( pExpr->iTable
projects / thirdparty / sqlite.git / commitdiff
