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+/*
+** 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"
+
+/* Forward declarations */
+static void exprCodeBetween(Parse*,Expr*,int,void(*)(Parse*,Expr*,int,int),int);
+static int exprCodeVector(Parse *pParse, Expr *p, int *piToFree);
+
+/*
+** Return the affinity character for a single column of a table.
+*/
+char sqlite3TableColumnAffinity(const Table *pTab, int iCol){
+ if( iCol<0 || NEVER(iCol>=pTab->nCol) ) return SQLITE_AFF_INTEGER;
+ return pTab->aCol[iCol].affinity;
+}
+
+/*
+** 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(const Expr *pExpr){
+ int op;
+ op = pExpr->op;
+ while( 1 /* exit-by-break */ ){
+ if( op==TK_COLUMN || (op==TK_AGG_COLUMN && pExpr->y.pTab!=0) ){
+ assert( ExprUseYTab(pExpr) );
+ assert( pExpr->y.pTab!=0 );
+ return sqlite3TableColumnAffinity(pExpr->y.pTab, pExpr->iColumn);
+ }
+ if( op==TK_SELECT ){
+ assert( ExprUseXSelect(pExpr) );
+ assert( pExpr->x.pSelect!=0 );
+ assert( pExpr->x.pSelect->pEList!=0 );
+ assert( pExpr->x.pSelect->pEList->a[0].pExpr!=0 );
+ 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_SELECT_COLUMN ){
+ assert( pExpr->pLeft!=0 && ExprUseXSelect(pExpr->pLeft) );
+ assert( pExpr->iColumn < pExpr->iTable );
+ assert( pExpr->iColumn >= 0 );
+ assert( pExpr->iTable==pExpr->pLeft->x.pSelect->pEList->nExpr );
+ return sqlite3ExprAffinity(
+ pExpr->pLeft->x.pSelect->pEList->a[pExpr->iColumn].pExpr
+ );
+ }
+ if( op==TK_VECTOR ){
+ assert( ExprUseXList(pExpr) );
+ return sqlite3ExprAffinity(pExpr->x.pList->a[0].pExpr);
+ }
+ if( ExprHasProperty(pExpr, EP_Skip|EP_IfNullRow) ){
+ assert( pExpr->op==TK_COLLATE
+ || pExpr->op==TK_IF_NULL_ROW
+ || (pExpr->op==TK_REGISTER && pExpr->op2==TK_IF_NULL_ROW) );
+ pExpr = pExpr->pLeft;
+ op = pExpr->op;
+ continue;
+ }
+ if( op!=TK_REGISTER || (op = pExpr->op2)==TK_REGISTER ) break;
+ }
+ return pExpr->affExpr;
+}
+
+/*
+** Make a guess at all the possible datatypes of the result that could
+** be returned by an expression. Return a bitmask indicating the answer:
+**
+** 0x01 Numeric
+** 0x02 Text
+** 0x04 Blob
+**
+** If the expression must return NULL, then 0x00 is returned.
+*/
+int sqlite3ExprDataType(const Expr *pExpr){
+ while( pExpr ){
+ switch( pExpr->op ){
+ case TK_COLLATE:
+ case TK_IF_NULL_ROW:
+ case TK_UPLUS: {
+ pExpr = pExpr->pLeft;
+ break;
+ }
+ case TK_NULL: {
+ pExpr = 0;
+ break;
+ }
+ case TK_STRING: {
+ return 0x02;
+ }
+ case TK_BLOB: {
+ return 0x04;
+ }
+ case TK_CONCAT: {
+ return 0x06;
+ }
+ case TK_VARIABLE:
+ case TK_AGG_FUNCTION:
+ case TK_FUNCTION: {
+ return 0x07;
+ }
+ case TK_COLUMN:
+ case TK_AGG_COLUMN:
+ case TK_SELECT:
+ case TK_CAST:
+ case TK_SELECT_COLUMN:
+ case TK_VECTOR: {
+ int aff = sqlite3ExprAffinity(pExpr);
+ if( aff>=SQLITE_AFF_NUMERIC ) return 0x05;
+ if( aff==SQLITE_AFF_TEXT ) return 0x06;
+ return 0x07;
+ }
+ case TK_CASE: {
+ int res = 0;
+ int ii;
+ ExprList *pList = pExpr->x.pList;
+ assert( ExprUseXList(pExpr) && pList!=0 );
+ assert( pList->nExpr > 0);
+ for(ii=1; ii<pList->nExpr; ii+=2){
+ res |= sqlite3ExprDataType(pList->a[ii].pExpr);
+ }
+ if( pList->nExpr % 2 ){
+ res |= sqlite3ExprDataType(pList->a[pList->nExpr-1].pExpr);
+ }
+ return res;
+ }
+ default: {
+ return 0x01;
+ }
+ } /* End of switch(op) */
+ } /* End of while(pExpr) */
+ return 0x00;
+}
+
+/*
+** 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(
+ const 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(
+ const Parse *pParse, /* Parsing context */
+ Expr *pExpr, /* Add the "COLLATE" clause to this expression */
+ const char *zC /* The collating sequence name */
+){
+ Token s;
+ assert( zC!=0 );
+ sqlite3TokenInit(&s, (char*)zC);
+ return sqlite3ExprAddCollateToken(pParse, pExpr, &s, 0);
+}
+
+/*
+** Skip over any TK_COLLATE operators.
+*/
+Expr *sqlite3ExprSkipCollate(Expr *pExpr){
+ while( pExpr && ExprHasProperty(pExpr, EP_Skip) ){
+ assert( pExpr->op==TK_COLLATE );
+ pExpr = pExpr->pLeft;
+ }
+ return pExpr;
+}
+
+/*
+** Skip over any TK_COLLATE operators and/or any unlikely()
+** or likelihood() or likely() functions at the root of an
+** expression.
+*/
+Expr *sqlite3ExprSkipCollateAndLikely(Expr *pExpr){
+ while( pExpr && ExprHasProperty(pExpr, EP_Skip|EP_Unlikely) ){
+ if( ExprHasProperty(pExpr, EP_Unlikely) ){
+ assert( ExprUseXList(pExpr) );
+ 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.
+**
+** See also: sqlite3ExprNNCollSeq()
+**
+** The sqlite3ExprNNCollSeq() works the same exact that it returns the
+** default collation if pExpr has no defined collation.
+**
+** 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, const Expr *pExpr){
+ sqlite3 *db = pParse->db;
+ CollSeq *pColl = 0;
+ const Expr *p = pExpr;
+ while( p ){
+ int op = p->op;
+ if( op==TK_REGISTER ) op = p->op2;
+ if( (op==TK_AGG_COLUMN && p->y.pTab!=0)
+ || op==TK_COLUMN || op==TK_TRIGGER
+ ){
+ int j;
+ assert( ExprUseYTab(p) );
+ assert( p->y.pTab!=0 );
+ if( (j = p->iColumn)>=0 ){
+ const char *zColl = sqlite3ColumnColl(&p->y.pTab->aCol[j]);
+ pColl = sqlite3FindCollSeq(db, ENC(db), zColl, 0);
+ }
+ break;
+ }
+ if( op==TK_CAST || op==TK_UPLUS ){
+ p = p->pLeft;
+ continue;
+ }
+ if( op==TK_VECTOR ){
+ assert( ExprUseXList(p) );
+ p = p->x.pList->a[0].pExpr;
+ continue;
+ }
+ if( op==TK_COLLATE ){
+ assert( !ExprHasProperty(p, EP_IntValue) );
+ pColl = sqlite3GetCollSeq(pParse, ENC(db), 0, p->u.zToken);
+ 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( !ExprUseXList(p) || p->x.pList==0 || p->pRight==0 );
+ if( ExprUseXList(p) && p->x.pList!=0 && !db->mallocFailed ){
+ int i;
+ for(i=0; 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;
+}
+
+/*
+** Return the collation sequence for the expression pExpr. If
+** there is no defined collating sequence, return a pointer to the
+** default collation sequence.
+**
+** See also: sqlite3ExprCollSeq()
+**
+** The sqlite3ExprCollSeq() routine works the same except that it
+** returns NULL if there is no defined collation.
+*/
+CollSeq *sqlite3ExprNNCollSeq(Parse *pParse, const Expr *pExpr){
+ CollSeq *p = sqlite3ExprCollSeq(pParse, pExpr);
+ if( p==0 ) p = pParse->db->pDfltColl;
+ assert( p!=0 );
+ return p;
+}
+
+/*
+** Return TRUE if the two expressions have equivalent collating sequences.
+*/
+int sqlite3ExprCollSeqMatch(Parse *pParse, const Expr *pE1, const Expr *pE2){
+ CollSeq *pColl1 = sqlite3ExprNNCollSeq(pParse, pE1);
+ CollSeq *pColl2 = sqlite3ExprNNCollSeq(pParse, pE2);
+ return sqlite3StrICmp(pColl1->zName, pColl2->zName)==0;
+}
+
+/*
+** 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(const Expr *pExpr, char aff2){
+ char aff1 = sqlite3ExprAffinity(pExpr);
+ if( aff1>SQLITE_AFF_NONE && aff2>SQLITE_AFF_NONE ){
+ /* 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{
+ /* One side is a column, the other is not. Use the columns affinity. */
+ assert( aff1<=SQLITE_AFF_NONE || aff2<=SQLITE_AFF_NONE );
+ return (aff1<=SQLITE_AFF_NONE ? aff2 : aff1) | SQLITE_AFF_NONE;
+ }
+}
+
+/*
+** pExpr is a comparison operator. Return the type affinity that should
+** be applied to both operands prior to doing the comparison.
+*/
+static char comparisonAffinity(const 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( ExprUseXSelect(pExpr) ){
+ aff = sqlite3CompareAffinity(pExpr->x.pSelect->pEList->a[0].pExpr, aff);
+ }else if( aff==0 ){
+ 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(const Expr *pExpr, char idx_affinity){
+ char aff = comparisonAffinity(pExpr);
+ if( aff<SQLITE_AFF_TEXT ){
+ return 1;
+ }
+ if( aff==SQLITE_AFF_TEXT ){
+ return idx_affinity==SQLITE_AFF_TEXT;
+ }
+ 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(
+ const Expr *pExpr1, /* Left operand */
+ const Expr *pExpr2, /* Right operand */
+ int jumpIfNull /* Extra flags added to P5 */
+){
+ 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,
+ const Expr *pLeft,
+ const 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;
+}
+
+/* Expression p is a comparison operator. Return a collation sequence
+** appropriate for the comparison operator.
+**
+** This is normally just a wrapper around sqlite3BinaryCompareCollSeq().
+** However, if the OP_Commuted flag is set, then the order of the operands
+** is reversed in the sqlite3BinaryCompareCollSeq() call so that the
+** correct collating sequence is found.
+*/
+CollSeq *sqlite3ExprCompareCollSeq(Parse *pParse, const Expr *p){
+ if( ExprHasProperty(p, EP_Commuted) ){
+ return sqlite3BinaryCompareCollSeq(pParse, p->pRight, p->pLeft);
+ }else{
+ return sqlite3BinaryCompareCollSeq(pParse, p->pLeft, p->pRight);
+ }
+}
+
+/*
+** 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 isCommuted /* The comparison has been commuted */
+){
+ int p5;
+ int addr;
+ CollSeq *p4;
+
+ if( pParse->nErr ) return 0;
+ if( isCommuted ){
+ p4 = sqlite3BinaryCompareCollSeq(pParse, pRight, pLeft);
+ }else{
+ 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;
+}
+
+/*
+** Return true if expression pExpr is a vector, or false otherwise.
+**
+** A vector is defined as any expression that results in two or more
+** columns of result. Every TK_VECTOR node is an vector because the
+** parser will not generate a TK_VECTOR with fewer than two entries.
+** But a TK_SELECT might be either a vector or a scalar. It is only
+** considered a vector if it has two or more result columns.
+*/
+int sqlite3ExprIsVector(const Expr *pExpr){
+ return sqlite3ExprVectorSize(pExpr)>1;
+}
+
+/*
+** If the expression passed as the only argument is of type TK_VECTOR
+** return the number of expressions in the vector. Or, if the expression
+** is a sub-select, return the number of columns in the sub-select. For
+** any other type of expression, return 1.
+*/
+int sqlite3ExprVectorSize(const Expr *pExpr){
+ u8 op = pExpr->op;
+ if( op==TK_REGISTER ) op = pExpr->op2;
+ if( op==TK_VECTOR ){
+ assert( ExprUseXList(pExpr) );
+ return pExpr->x.pList->nExpr;
+ }else if( op==TK_SELECT ){
+ assert( ExprUseXSelect(pExpr) );
+ return pExpr->x.pSelect->pEList->nExpr;
+ }else{
+ return 1;
+ }
+}
+
+/*
+** Return a pointer to a subexpression of pVector that is the i-th
+** column of the vector (numbered starting with 0). The caller must
+** ensure that i is within range.
+**
+** If pVector is really a scalar (and "scalar" here includes subqueries
+** that return a single column!) then return pVector unmodified.
+**
+** pVector retains ownership of the returned subexpression.
+**
+** If the vector is a (SELECT ...) then the expression returned is
+** just the expression for the i-th term of the result set, and may
+** not be ready for evaluation because the table cursor has not yet
+** been positioned.
+*/
+Expr *sqlite3VectorFieldSubexpr(Expr *pVector, int i){
+ assert( i<sqlite3ExprVectorSize(pVector) || pVector->op==TK_ERROR );
+ if( sqlite3ExprIsVector(pVector) ){
+ assert( pVector->op2==0 || pVector->op==TK_REGISTER );
+ if( pVector->op==TK_SELECT || pVector->op2==TK_SELECT ){
+ assert( ExprUseXSelect(pVector) );
+ return pVector->x.pSelect->pEList->a[i].pExpr;
+ }else{
+ assert( ExprUseXList(pVector) );
+ return pVector->x.pList->a[i].pExpr;
+ }
+ }
+ return pVector;
+}
+
+/*
+** Compute and return a new Expr object which when passed to
+** sqlite3ExprCode() will generate all necessary code to compute
+** the iField-th column of the vector expression pVector.
+**
+** It is ok for pVector to be a scalar (as long as iField==0).
+** In that case, this routine works like sqlite3ExprDup().
+**
+** The caller owns the returned Expr object and is responsible for
+** ensuring that the returned value eventually gets freed.
+**
+** The caller retains ownership of pVector. If pVector is a TK_SELECT,
+** then the returned object will reference pVector and so pVector must remain
+** valid for the life of the returned object. If pVector is a TK_VECTOR
+** or a scalar expression, then it can be deleted as soon as this routine
+** returns.
+**
+** A trick to cause a TK_SELECT pVector to be deleted together with
+** the returned Expr object is to attach the pVector to the pRight field
+** of the returned TK_SELECT_COLUMN Expr object.
+*/
+Expr *sqlite3ExprForVectorField(
+ Parse *pParse, /* Parsing context */
+ Expr *pVector, /* The vector. List of expressions or a sub-SELECT */
+ int iField, /* Which column of the vector to return */
+ int nField /* Total number of columns in the vector */
+){
+ Expr *pRet;
+ if( pVector->op==TK_SELECT ){
+ assert( ExprUseXSelect(pVector) );
+ /* The TK_SELECT_COLUMN Expr node:
+ **
+ ** pLeft: pVector containing TK_SELECT. Not deleted.
+ ** pRight: not used. But recursively deleted.
+ ** iColumn: Index of a column in pVector
+ ** iTable: 0 or the number of columns on the LHS of an assignment
+ ** pLeft->iTable: First in an array of register holding result, or 0
+ ** if the result is not yet computed.
+ **
+ ** sqlite3ExprDelete() specifically skips the recursive delete of
+ ** pLeft on TK_SELECT_COLUMN nodes. But pRight is followed, so pVector
+ ** can be attached to pRight to cause this node to take ownership of
+ ** pVector. Typically there will be multiple TK_SELECT_COLUMN nodes
+ ** with the same pLeft pointer to the pVector, but only one of them
+ ** will own the pVector.
+ */
+ pRet = sqlite3PExpr(pParse, TK_SELECT_COLUMN, 0, 0);
+ if( pRet ){
+ ExprSetProperty(pRet, EP_FullSize);
+ pRet->iTable = nField;
+ pRet->iColumn = iField;
+ pRet->pLeft = pVector;
+ }
+ }else{
+ if( pVector->op==TK_VECTOR ){
+ Expr **ppVector;
+ assert( ExprUseXList(pVector) );
+ ppVector = &pVector->x.pList->a[iField].pExpr;
+ pVector = *ppVector;
+ if( IN_RENAME_OBJECT ){
+ /* This must be a vector UPDATE inside a trigger */
+ *ppVector = 0;
+ return pVector;
+ }
+ }
+ pRet = sqlite3ExprDup(pParse->db, pVector, 0);
+ }
+ return pRet;
+}
+
+/*
+** If expression pExpr is of type TK_SELECT, generate code to evaluate
+** it. Return the register in which the result is stored (or, if the
+** sub-select returns more than one column, the first in an array
+** of registers in which the result is stored).
+**
+** If pExpr is not a TK_SELECT expression, return 0.
+*/
+static int exprCodeSubselect(Parse *pParse, Expr *pExpr){
+ int reg = 0;
+#ifndef SQLITE_OMIT_SUBQUERY
+ if( pExpr->op==TK_SELECT ){
+ reg = sqlite3CodeSubselect(pParse, pExpr);
+ }
+#endif
+ return reg;
+}
+
+/*
+** Argument pVector points to a vector expression - either a TK_VECTOR
+** or TK_SELECT that returns more than one column. This function returns
+** the register number of a register that contains the value of
+** element iField of the vector.
+**
+** If pVector is a TK_SELECT expression, then code for it must have
+** already been generated using the exprCodeSubselect() routine. In this
+** case parameter regSelect should be the first in an array of registers
+** containing the results of the sub-select.
+**
+** If pVector is of type TK_VECTOR, then code for the requested field
+** is generated. In this case (*pRegFree) may be set to the number of
+** a temporary register to be freed by the caller before returning.
+**
+** Before returning, output parameter (*ppExpr) is set to point to the
+** Expr object corresponding to element iElem of the vector.
+*/
+static int exprVectorRegister(
+ Parse *pParse, /* Parse context */
+ Expr *pVector, /* Vector to extract element from */
+ int iField, /* Field to extract from pVector */
+ int regSelect, /* First in array of registers */
+ Expr **ppExpr, /* OUT: Expression element */
+ int *pRegFree /* OUT: Temp register to free */
+){
+ u8 op = pVector->op;
+ assert( op==TK_VECTOR || op==TK_REGISTER || op==TK_SELECT || op==TK_ERROR );
+ if( op==TK_REGISTER ){
+ *ppExpr = sqlite3VectorFieldSubexpr(pVector, iField);
+ return pVector->iTable+iField;
+ }
+ if( op==TK_SELECT ){
+ assert( ExprUseXSelect(pVector) );
+ *ppExpr = pVector->x.pSelect->pEList->a[iField].pExpr;
+ return regSelect+iField;
+ }
+ if( op==TK_VECTOR ){
+ assert( ExprUseXList(pVector) );
+ *ppExpr = pVector->x.pList->a[iField].pExpr;
+ return sqlite3ExprCodeTemp(pParse, *ppExpr, pRegFree);
+ }
+ return 0;
+}
+
+/*
+** Expression pExpr is a comparison between two vector values. Compute
+** the result of the comparison (1, 0, or NULL) and write that
+** result into register dest.
+**
+** The caller must satisfy the following preconditions:
+**
+** if pExpr->op==TK_IS: op==TK_EQ and p5==SQLITE_NULLEQ
+** if pExpr->op==TK_ISNOT: op==TK_NE and p5==SQLITE_NULLEQ
+** otherwise: op==pExpr->op and p5==0
+*/
+static void codeVectorCompare(
+ Parse *pParse, /* Code generator context */
+ Expr *pExpr, /* The comparison operation */
+ int dest, /* Write results into this register */
+ u8 op, /* Comparison operator */
+ u8 p5 /* SQLITE_NULLEQ or zero */
+){
+ Vdbe *v = pParse->pVdbe;
+ Expr *pLeft = pExpr->pLeft;
+ Expr *pRight = pExpr->pRight;
+ int nLeft = sqlite3ExprVectorSize(pLeft);
+ int i;
+ int regLeft = 0;
+ int regRight = 0;
+ u8 opx = op;
+ int addrCmp = 0;
+ int addrDone = sqlite3VdbeMakeLabel(pParse);
+ int isCommuted = ExprHasProperty(pExpr,EP_Commuted);
+
+ assert( !ExprHasVVAProperty(pExpr,EP_Immutable) );
+ if( pParse->nErr ) return;
+ if( nLeft!=sqlite3ExprVectorSize(pRight) ){
+ sqlite3ErrorMsg(pParse, "row value misused");
+ return;
+ }
+ assert( pExpr->op==TK_EQ || pExpr->op==TK_NE
+ || pExpr->op==TK_IS || pExpr->op==TK_ISNOT
+ || pExpr->op==TK_LT || pExpr->op==TK_GT
+ || pExpr->op==TK_LE || pExpr->op==TK_GE
+ );
+ assert( pExpr->op==op || (pExpr->op==TK_IS && op==TK_EQ)
+ || (pExpr->op==TK_ISNOT && op==TK_NE) );
+ assert( p5==0 || pExpr->op!=op );
+ assert( p5==SQLITE_NULLEQ || pExpr->op==op );
+
+ if( op==TK_LE ) opx = TK_LT;
+ if( op==TK_GE ) opx = TK_GT;
+ if( op==TK_NE ) opx = TK_EQ;
+
+ regLeft = exprCodeSubselect(pParse, pLeft);
+ regRight = exprCodeSubselect(pParse, pRight);
+
+ sqlite3VdbeAddOp2(v, OP_Integer, 1, dest);
+ for(i=0; 1 /*Loop exits by "break"*/; i++){
+ int regFree1 = 0, regFree2 = 0;
+ Expr *pL = 0, *pR = 0;
+ int r1, r2;
+ assert( i>=0 && i<nLeft );
+ if( addrCmp ) sqlite3VdbeJumpHere(v, addrCmp);
+ r1 = exprVectorRegister(pParse, pLeft, i, regLeft, &pL, &regFree1);
+ r2 = exprVectorRegister(pParse, pRight, i, regRight, &pR, &regFree2);
+ addrCmp = sqlite3VdbeCurrentAddr(v);
+ codeCompare(pParse, pL, pR, opx, r1, r2, addrDone, p5, isCommuted);
+ testcase(op==OP_Lt); VdbeCoverageIf(v,op==OP_Lt);
+ testcase(op==OP_Le); VdbeCoverageIf(v,op==OP_Le);
+ testcase(op==OP_Gt); VdbeCoverageIf(v,op==OP_Gt);
+ testcase(op==OP_Ge); VdbeCoverageIf(v,op==OP_Ge);
+ testcase(op==OP_Eq); VdbeCoverageIf(v,op==OP_Eq);
+ testcase(op==OP_Ne); VdbeCoverageIf(v,op==OP_Ne);
+ sqlite3ReleaseTempReg(pParse, regFree1);
+ sqlite3ReleaseTempReg(pParse, regFree2);
+ if( (opx==TK_LT || opx==TK_GT) && i<nLeft-1 ){
+ addrCmp = sqlite3VdbeAddOp0(v, OP_ElseEq);
+ testcase(opx==TK_LT); VdbeCoverageIf(v,opx==TK_LT);
+ testcase(opx==TK_GT); VdbeCoverageIf(v,opx==TK_GT);
+ }
+ if( p5==SQLITE_NULLEQ ){
+ sqlite3VdbeAddOp2(v, OP_Integer, 0, dest);
+ }else{
+ sqlite3VdbeAddOp3(v, OP_ZeroOrNull, r1, dest, r2);
+ }
+ if( i==nLeft-1 ){
+ break;
+ }
+ if( opx==TK_EQ ){
+ sqlite3VdbeAddOp2(v, OP_NotNull, dest, addrDone); VdbeCoverage(v);
+ }else{
+ assert( op==TK_LT || op==TK_GT || op==TK_LE || op==TK_GE );
+ sqlite3VdbeAddOp2(v, OP_Goto, 0, addrDone);
+ if( i==nLeft-2 ) opx = op;
+ }
+ }
+ sqlite3VdbeJumpHere(v, addrCmp);
+ sqlite3VdbeResolveLabel(v, addrDone);
+ if( op==TK_NE ){
+ sqlite3VdbeAddOp2(v, OP_Not, dest, dest);
+ }
+}
+
+#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(const Expr *p, int *pnHeight){
+ if( p ){
+ if( p->nHeight>*pnHeight ){
+ *pnHeight = p->nHeight;
+ }
+ }
+}
+static void heightOfExprList(const ExprList *p, int *pnHeight){
+ if( p ){
+ int i;
+ for(i=0; i<p->nExpr; i++){
+ heightOfExpr(p->a[i].pExpr, pnHeight);
+ }
+ }
+}
+static void heightOfSelect(const Select *pSelect, int *pnHeight){
+ const Select *p;
+ for(p=pSelect; p; p=p->pPrior){
+ heightOfExpr(p->pWhere, pnHeight);
+ heightOfExpr(p->pHaving, pnHeight);
+ heightOfExpr(p->pLimit, pnHeight);
+ heightOfExprList(p->pEList, pnHeight);
+ heightOfExprList(p->pGroupBy, pnHeight);
+ heightOfExprList(p->pOrderBy, 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 = p->pLeft ? p->pLeft->nHeight : 0;
+ if( NEVER(p->pRight) && p->pRight->nHeight>nHeight ){
+ nHeight = p->pRight->nHeight;
+ }
+ if( ExprUseXSelect(p) ){
+ 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(const 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( pParse->nErr ) return;
+ if( p && ExprUseXList(p) && p->x.pList ){
+ p->flags |= EP_Propagate & sqlite3ExprListFlags(p->x.pList);
+ }
+}
+#define exprSetHeight(y)
+#endif /* SQLITE_MAX_EXPR_DEPTH>0 */
+
+/*
+** Set the error offset for an Expr node, if possible.
+*/
+void sqlite3ExprSetErrorOffset(Expr *pExpr, int iOfst){
+ if( pExpr==0 ) return;
+ if( NEVER(ExprUseWJoin(pExpr)) ) return;
+ pExpr->w.iOfst = iOfst;
+}
+
+/*
+** 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 sqlite3DbMallocRawNN() */
+ 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|EP_Leaf|(iValue?EP_IsTrue:EP_IsFalse);
+ pNew->u.iValue = iValue;
+ }else{
+ 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 && sqlite3Isquote(pNew->u.zToken[0]) ){
+ sqlite3DequoteExpr(pNew);
+ }
+ }
+ }
+#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 = sqlite3Strlen30(zToken);
+ 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{
+ assert( ExprUseXList(pRoot) );
+ assert( pRoot->x.pSelect==0 );
+ if( pRight ){
+ pRoot->pRight = pRight;
+ pRoot->flags |= EP_Propagate & pRight->flags;
+#if SQLITE_MAX_EXPR_DEPTH>0
+ pRoot->nHeight = pRight->nHeight+1;
+ }else{
+ pRoot->nHeight = 1;
+#endif
+ }
+ if( pLeft ){
+ pRoot->pLeft = pLeft;
+ pRoot->flags |= EP_Propagate & pLeft->flags;
+#if SQLITE_MAX_EXPR_DEPTH>0
+ if( pLeft->nHeight>=pRoot->nHeight ){
+ pRoot->nHeight = pLeft->nHeight+1;
+ }
+#endif
+ }
+ }
+}
+
+/*
+** 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 */
+){
+ Expr *p;
+ p = sqlite3DbMallocRawNN(pParse->db, sizeof(Expr));
+ if( p ){
+ memset(p, 0, sizeof(Expr));
+ p->op = op & 0xff;
+ p->iAgg = -1;
+ sqlite3ExprAttachSubtrees(pParse->db, p, pLeft, pRight);
+ sqlite3ExprCheckHeight(pParse, p->nHeight);
+ }else{
+ sqlite3ExprDelete(pParse->db, pLeft);
+ sqlite3ExprDelete(pParse->db, pRight);
+ }
+ return p;
+}
+
+/*
+** Add pSelect to the Expr.x.pSelect field. Or, if pExpr is NULL (due
+** do a memory allocation failure) then delete the pSelect object.
+*/
+void sqlite3PExprAddSelect(Parse *pParse, Expr *pExpr, Select *pSelect){
+ if( pExpr ){
+ pExpr->x.pSelect = pSelect;
+ ExprSetProperty(pExpr, EP_xIsSelect|EP_Subquery);
+ sqlite3ExprSetHeightAndFlags(pParse, pExpr);
+ }else{
+ assert( pParse->db->mallocFailed );
+ sqlite3SelectDelete(pParse->db, pSelect);
+ }
+}
+
+/*
+** Expression list pEList is a list of vector values. This function
+** converts the contents of pEList to a VALUES(...) Select statement
+** returning 1 row for each element of the list. For example, the
+** expression list:
+**
+** ( (1,2), (3,4) (5,6) )
+**
+** is translated to the equivalent of:
+**
+** VALUES(1,2), (3,4), (5,6)
+**
+** Each of the vector values in pEList must contain exactly nElem terms.
+** If a list element that is not a vector or does not contain nElem terms,
+** an error message is left in pParse.
+**
+** This is used as part of processing IN(...) expressions with a list
+** of vectors on the RHS. e.g. "... IN ((1,2), (3,4), (5,6))".
+*/
+Select *sqlite3ExprListToValues(Parse *pParse, int nElem, ExprList *pEList){
+ int ii;
+ Select *pRet = 0;
+ assert( nElem>1 );
+ for(ii=0; ii<pEList->nExpr; ii++){
+ Select *pSel;
+ Expr *pExpr = pEList->a[ii].pExpr;
+ int nExprElem;
+ if( pExpr->op==TK_VECTOR ){
+ assert( ExprUseXList(pExpr) );
+ nExprElem = pExpr->x.pList->nExpr;
+ }else{
+ nExprElem = 1;
+ }
+ if( nExprElem!=nElem ){
+ sqlite3ErrorMsg(pParse, "IN(...) element has %d term%s - expected %d",
+ nExprElem, nExprElem>1?"s":"", nElem
+ );
+ break;
+ }
+ assert( ExprUseXList(pExpr) );
+ pSel = sqlite3SelectNew(pParse, pExpr->x.pList, 0, 0, 0, 0, 0, SF_Values,0);
+ pExpr->x.pList = 0;
+ if( pSel ){
+ if( pRet ){
+ pSel->op = TK_ALL;
+ pSel->pPrior = pRet;
+ }
+ pRet = pSel;
+ }
+ }
+
+ if( pRet && pRet->pPrior ){
+ pRet->selFlags |= SF_MultiValue;
+ }
+ sqlite3ExprListDelete(pParse->db, pEList);
+ return pRet;
+}
+
+/*
+** 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, and neither side
+** is part of an ON clause, then instead of returning an AND expression,
+** just return a constant expression with a value of false.
+*/
+Expr *sqlite3ExprAnd(Parse *pParse, Expr *pLeft, Expr *pRight){
+ sqlite3 *db = pParse->db;
+ if( pLeft==0 ){
+ return pRight;
+ }else if( pRight==0 ){
+ return pLeft;
+ }else{
+ u32 f = pLeft->flags | pRight->flags;
+ if( (f&(EP_OuterON|EP_InnerON|EP_IsFalse))==EP_IsFalse
+ && !IN_RENAME_OBJECT
+ ){
+ sqlite3ExprDeferredDelete(pParse, pLeft);
+ sqlite3ExprDeferredDelete(pParse, pRight);
+ return sqlite3Expr(db, TK_INTEGER, "0");
+ }else{
+ return sqlite3PExpr(pParse, TK_AND, pLeft, pRight);
+ }
+ }
+}
+
+/*
+** Construct a new expression node for a function with multiple
+** arguments.
+*/
+Expr *sqlite3ExprFunction(
+ Parse *pParse, /* Parsing context */
+ ExprList *pList, /* Argument list */
+ const Token *pToken, /* Name of the function */
+ int eDistinct /* SF_Distinct or SF_ALL or 0 */
+){
+ 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;
+ }
+ assert( !ExprHasProperty(pNew, EP_InnerON|EP_OuterON) );
+ pNew->w.iOfst = (int)(pToken->z - pParse->zTail);
+ if( pList
+ && pList->nExpr > pParse->db->aLimit[SQLITE_LIMIT_FUNCTION_ARG]
+ && !pParse->nested
+ ){
+ sqlite3ErrorMsg(pParse, "too many arguments on function %T", pToken);
+ }
+ pNew->x.pList = pList;
+ ExprSetProperty(pNew, EP_HasFunc);
+ assert( ExprUseXList(pNew) );
+ sqlite3ExprSetHeightAndFlags(pParse, pNew);
+ if( eDistinct==SF_Distinct ) ExprSetProperty(pNew, EP_Distinct);
+ return pNew;
+}
+
+/*
+** Report an error when attempting to use an ORDER BY clause within
+** the arguments of a non-aggregate function.
+*/
+void sqlite3ExprOrderByAggregateError(Parse *pParse, Expr *p){
+ sqlite3ErrorMsg(pParse,
+ "ORDER BY may not be used with non-aggregate %#T()", p
+ );
+}
+
+/*
+** Attach an ORDER BY clause to a function call.
+**
+** functionname( arguments ORDER BY sortlist )
+** \_____________________/ \______/
+** pExpr pOrderBy
+**
+** The ORDER BY clause is inserted into a new Expr node of type TK_ORDER
+** and added to the Expr.pLeft field of the parent TK_FUNCTION node.
+*/
+void sqlite3ExprAddFunctionOrderBy(
+ Parse *pParse, /* Parsing context */
+ Expr *pExpr, /* The function call to which ORDER BY is to be added */
+ ExprList *pOrderBy /* The ORDER BY clause to add */
+){
+ Expr *pOB;
+ sqlite3 *db = pParse->db;
+ if( NEVER(pOrderBy==0) ){
+ assert( db->mallocFailed );
+ return;
+ }
+ if( pExpr==0 ){
+ assert( db->mallocFailed );
+ sqlite3ExprListDelete(db, pOrderBy);
+ return;
+ }
+ assert( pExpr->op==TK_FUNCTION );
+ assert( pExpr->pLeft==0 );
+ assert( ExprUseXList(pExpr) );
+ if( pExpr->x.pList==0 || NEVER(pExpr->x.pList->nExpr==0) ){
+ /* Ignore ORDER BY on zero-argument aggregates */
+ sqlite3ParserAddCleanup(pParse, sqlite3ExprListDeleteGeneric, pOrderBy);
+ return;
+ }
+ if( IsWindowFunc(pExpr) ){
+ sqlite3ExprOrderByAggregateError(pParse, pExpr);
+ sqlite3ExprListDelete(db, pOrderBy);
+ return;
+ }
+
+ pOB = sqlite3ExprAlloc(db, TK_ORDER, 0, 0);
+ if( pOB==0 ){
+ sqlite3ExprListDelete(db, pOrderBy);
+ return;
+ }
+ pOB->x.pList = pOrderBy;
+ assert( ExprUseXList(pOB) );
+ pExpr->pLeft = pOB;
+ ExprSetProperty(pOB, EP_FullSize);
+}
+
+/*
+** Check to see if a function is usable according to current access
+** rules:
+**
+** SQLITE_FUNC_DIRECT - Only usable from top-level SQL
+**
+** SQLITE_FUNC_UNSAFE - Usable if TRUSTED_SCHEMA or from
+** top-level SQL
+**
+** If the function is not usable, create an error.
+*/
+void sqlite3ExprFunctionUsable(
+ Parse *pParse, /* Parsing and code generating context */
+ const Expr *pExpr, /* The function invocation */
+ const FuncDef *pDef /* The function being invoked */
+){
+ assert( !IN_RENAME_OBJECT );
+ assert( (pDef->funcFlags & (SQLITE_FUNC_DIRECT|SQLITE_FUNC_UNSAFE))!=0 );
+ if( ExprHasProperty(pExpr, EP_FromDDL) ){
+ if( (pDef->funcFlags & SQLITE_FUNC_DIRECT)!=0
+ || (pParse->db->flags & SQLITE_TrustedSchema)==0
+ ){
+ /* Functions prohibited in triggers and views if:
+ ** (1) tagged with SQLITE_DIRECTONLY
+ ** (2) not tagged with SQLITE_INNOCUOUS (which means it
+ ** is tagged with SQLITE_FUNC_UNSAFE) and
+ ** SQLITE_DBCONFIG_TRUSTED_SCHEMA is off (meaning
+ ** that the schema is possibly tainted).
+ */
+ sqlite3ErrorMsg(pParse, "unsafe use of %#T()", pExpr);
+ }
+ }
+}
+
+/*
+** 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 big to avoid a denial of service attack when
+** the SQL statement comes from an external source.
+**
+** Wildcards of the form ":aaa", "@aaa", or "$aaa" are assigned the same number
+** as the previous instance of the same wildcard. Or if this is the first
+** instance of the wildcard, the next sequential variable number is
+** assigned.
+*/
+void sqlite3ExprAssignVarNumber(Parse *pParse, Expr *pExpr, u32 n){
+ sqlite3 *db = pParse->db;
+ const char *z;
+ ynVar x;
+
+ if( pExpr==0 ) return;
+ assert( !ExprHasProperty(pExpr, EP_IntValue|EP_Reduced|EP_TokenOnly) );
+ z = pExpr->u.zToken;
+ assert( z!=0 );
+ assert( z[0]!=0 );
+ assert( n==(u32)sqlite3Strlen30(z) );
+ if( z[1]==0 ){
+ /* Wildcard of the form "?". Assign the next variable number */
+ assert( z[0]=='?' );
+ x = (ynVar)(++pParse->nVar);
+ }else{
+ int doAdd = 0;
+ if( z[0]=='?' ){
+ /* Wildcard of the form "?nnn". Convert "nnn" to an integer and
+ ** use it as the variable number */
+ i64 i;
+ int bOk;
+ if( n==2 ){ /*OPTIMIZATION-IF-TRUE*/
+ i = z[1]-'0'; /* The common case of ?N for a single digit N */
+ bOk = 1;
+ }else{
+ bOk = 0==sqlite3Atoi64(&z[1], &i, n-1, SQLITE_UTF8);
+ }
+ testcase( i==0 );
+ testcase( i==1 );
+ testcase( i==db->aLimit[SQLITE_LIMIT_VARIABLE_NUMBER]-1 );
+ testcase( i==db->aLimit[SQLITE_LIMIT_VARIABLE_NUMBER] );
+ if( bOk==0 || i<1 || i>db->aLimit[SQLITE_LIMIT_VARIABLE_NUMBER] ){
+ sqlite3ErrorMsg(pParse, "variable number must be between ?1 and ?%d",
+ db->aLimit[SQLITE_LIMIT_VARIABLE_NUMBER]);
+ sqlite3RecordErrorOffsetOfExpr(pParse->db, pExpr);
+ return;
+ }
+ x = (ynVar)i;
+ if( x>pParse->nVar ){
+ pParse->nVar = (int)x;
+ doAdd = 1;
+ }else if( sqlite3VListNumToName(pParse->pVList, x)==0 ){
+ doAdd = 1;
+ }
+ }else{
+ /* Wildcards like ":aaa", "$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
+ */
+ x = (ynVar)sqlite3VListNameToNum(pParse->pVList, z, n);
+ if( x==0 ){
+ x = (ynVar)(++pParse->nVar);
+ doAdd = 1;
+ }
+ }
+ if( doAdd ){
+ pParse->pVList = sqlite3VListAdd(db, pParse->pVList, z, n, x);
+ }
+ }
+ pExpr->iColumn = x;
+ if( x>db->aLimit[SQLITE_LIMIT_VARIABLE_NUMBER] ){
+ sqlite3ErrorMsg(pParse, "too many SQL variables");
+ sqlite3RecordErrorOffsetOfExpr(pParse->db, pExpr);
+ }
+}
+
+/*
+** Recursively delete an expression tree.
+*/
+static SQLITE_NOINLINE void sqlite3ExprDeleteNN(sqlite3 *db, Expr *p){
+ assert( p!=0 );
+ assert( db!=0 );
+ assert( !ExprUseUValue(p) || p->u.iValue>=0 );
+ assert( !ExprUseYWin(p) || !ExprUseYSub(p) );
+ assert( !ExprUseYWin(p) || p->y.pWin!=0 || db->mallocFailed );
+ assert( p->op!=TK_FUNCTION || !ExprUseYSub(p) );
+#ifdef SQLITE_DEBUG
+ if( ExprHasProperty(p, EP_Leaf) && !ExprHasProperty(p, EP_TokenOnly) ){
+ assert( p->pLeft==0 );
+ assert( p->pRight==0 );
+ assert( !ExprUseXSelect(p) || p->x.pSelect==0 );
+ assert( !ExprUseXList(p) || p->x.pList==0 );
+ }
+#endif
+ if( !ExprHasProperty(p, (EP_TokenOnly|EP_Leaf)) ){
+ /* The Expr.x union is never used at the same time as Expr.pRight */
+ assert( (ExprUseXList(p) && p->x.pList==0) || p->pRight==0 );
+ if( p->pLeft && p->op!=TK_SELECT_COLUMN ) sqlite3ExprDeleteNN(db, p->pLeft);
+ if( p->pRight ){
+ assert( !ExprHasProperty(p, EP_WinFunc) );
+ sqlite3ExprDeleteNN(db, p->pRight);
+ }else if( ExprUseXSelect(p) ){
+ assert( !ExprHasProperty(p, EP_WinFunc) );
+ sqlite3SelectDelete(db, p->x.pSelect);
+ }else{
+ sqlite3ExprListDelete(db, p->x.pList);
+#ifndef SQLITE_OMIT_WINDOWFUNC
+ if( ExprHasProperty(p, EP_WinFunc) ){
+ sqlite3WindowDelete(db, p->y.pWin);
+ }
+#endif
+ }
+ }
+ if( !ExprHasProperty(p, EP_Static) ){
+ sqlite3DbNNFreeNN(db, p);
+ }
+}
+void sqlite3ExprDelete(sqlite3 *db, Expr *p){
+ if( p ) sqlite3ExprDeleteNN(db, p);
+}
+void sqlite3ExprDeleteGeneric(sqlite3 *db, void *p){
+ if( ALWAYS(p) ) sqlite3ExprDeleteNN(db, (Expr*)p);
+}
+
+/*
+** Clear both elements of an OnOrUsing object
+*/
+void sqlite3ClearOnOrUsing(sqlite3 *db, OnOrUsing *p){
+ if( p==0 ){
+ /* Nothing to clear */
+ }else if( p->pOn ){
+ sqlite3ExprDeleteNN(db, p->pOn);
+ }else if( p->pUsing ){
+ sqlite3IdListDelete(db, p->pUsing);
+ }
+}
+
+/*
+** Arrange to cause pExpr to be deleted when the pParse is deleted.
+** This is similar to sqlite3ExprDelete() except that the delete is
+** deferred until the pParse is deleted.
+**
+** The pExpr might be deleted immediately on an OOM error.
+**
+** The deferred delete is (currently) implemented by adding the
+** pExpr to the pParse->pConstExpr list with a register number of 0.
+*/
+void sqlite3ExprDeferredDelete(Parse *pParse, Expr *pExpr){
+ sqlite3ParserAddCleanup(pParse, sqlite3ExprDeleteGeneric, pExpr);
+}
+
+/* Invoke sqlite3RenameExprUnmap() and sqlite3ExprDelete() on the
+** expression.
+*/
+void sqlite3ExprUnmapAndDelete(Parse *pParse, Expr *p){
+ if( p ){
+ if( IN_RENAME_OBJECT ){
+ sqlite3RenameExprUnmap(pParse, p);
+ }
+ sqlite3ExprDeleteNN(pParse->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(const 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 the 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(const 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 || ExprHasProperty(p, EP_FullSize) ){
+ nSize = EXPR_FULLSIZE;
+ }else{
+ assert( !ExprHasProperty(p, EP_TokenOnly|EP_Reduced) );
+ assert( !ExprHasProperty(p, EP_OuterON) );
+ assert( !ExprHasVVAProperty(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(const Expr *p, int flags){
+ int nByte = dupedExprStructSize(p, flags) & 0xfff;
+ if( !ExprHasProperty(p, EP_IntValue) && p->u.zToken ){
+ nByte += sqlite3Strlen30NN(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 value returned includes space to create a copy of the Expr struct
+** itself and the buffer referred to by Expr.u.zToken, if any.
+**
+** The return value includes space to duplicate all Expr nodes in the
+** tree formed by Expr.pLeft and Expr.pRight, but not any other
+** substructure such as Expr.x.pList, Expr.x.pSelect, and Expr.y.pWin.
+*/
+static int dupedExprSize(const Expr *p){
+ int nByte;
+ assert( p!=0 );
+ nByte = dupedExprNodeSize(p, EXPRDUP_REDUCE);
+ if( p->pLeft ) nByte += dupedExprSize(p->pLeft);
+ if( p->pRight ) nByte += dupedExprSize(p->pRight);
+ assert( nByte==ROUND8(nByte) );
+ return nByte;
+}
+
+/*
+** An EdupBuf is a memory allocation used to stored multiple Expr objects
+** together with their Expr.zToken content. This is used to help implement
+** compression while doing sqlite3ExprDup(). The top-level Expr does the
+** allocation for itself and many of its decendents, then passes an instance
+** of the structure down into exprDup() so that they decendents can have
+** access to that memory.
+*/
+typedef struct EdupBuf EdupBuf;
+struct EdupBuf {
+ u8 *zAlloc; /* Memory space available for storage */
+#ifdef SQLITE_DEBUG
+ u8 *zEnd; /* First byte past the end of memory */
+#endif
+};
+
+/*
+** This function is similar to sqlite3ExprDup(), except that if pEdupBuf
+** is not NULL then it points to memory that can be used to store a copy
+** of the input Expr p together with its p->u.zToken (if any). pEdupBuf
+** is updated with the new buffer tail prior to returning.
+*/
+static Expr *exprDup(
+ sqlite3 *db, /* Database connection (for memory allocation) */
+ const Expr *p, /* Expr tree to be duplicated */
+ int dupFlags, /* EXPRDUP_REDUCE for compression. 0 if not */
+ EdupBuf *pEdupBuf /* Preallocated storage space, or NULL */
+){
+ Expr *pNew; /* Value to return */
+ EdupBuf sEdupBuf; /* Memory space from which to build Expr object */
+ u32 staticFlag; /* EP_Static if space not obtained from malloc */
+ int nToken = -1; /* Space needed for p->u.zToken. -1 means unknown */
+
+ assert( db!=0 );
+ assert( p );
+ assert( dupFlags==0 || dupFlags==EXPRDUP_REDUCE );
+ assert( pEdupBuf==0 || dupFlags==EXPRDUP_REDUCE );
+
+ /* Figure out where to write the new Expr structure. */
+ if( pEdupBuf ){
+ sEdupBuf.zAlloc = pEdupBuf->zAlloc;
+#ifdef SQLITE_DEBUG
+ sEdupBuf.zEnd = pEdupBuf->zEnd;
+#endif
+ staticFlag = EP_Static;
+ assert( sEdupBuf.zAlloc!=0 );
+ assert( dupFlags==EXPRDUP_REDUCE );
+ }else{
+ int nAlloc;
+ if( dupFlags ){
+ nAlloc = dupedExprSize(p);
+ }else if( !ExprHasProperty(p, EP_IntValue) && p->u.zToken ){
+ nToken = sqlite3Strlen30NN(p->u.zToken)+1;
+ nAlloc = ROUND8(EXPR_FULLSIZE + nToken);
+ }else{
+ nToken = 0;
+ nAlloc = ROUND8(EXPR_FULLSIZE);
+ }
+ assert( nAlloc==ROUND8(nAlloc) );
+ sEdupBuf.zAlloc = sqlite3DbMallocRawNN(db, nAlloc);
+#ifdef SQLITE_DEBUG
+ sEdupBuf.zEnd = sEdupBuf.zAlloc ? sEdupBuf.zAlloc+nAlloc : 0;
+#endif
+
+ staticFlag = 0;
+ }
+ pNew = (Expr *)sEdupBuf.zAlloc;
+ assert( EIGHT_BYTE_ALIGNMENT(pNew) );
+
+ 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, dupFlags);
+ int nNewSize = nStructSize & 0xfff;
+ if( nToken<0 ){
+ if( !ExprHasProperty(p, EP_IntValue) && p->u.zToken ){
+ nToken = sqlite3Strlen30(p->u.zToken) + 1;
+ }else{
+ nToken = 0;
+ }
+ }
+ if( dupFlags ){
+ assert( (int)(sEdupBuf.zEnd - sEdupBuf.zAlloc) >= nNewSize+nToken );
+ assert( ExprHasProperty(p, EP_Reduced)==0 );
+ memcpy(sEdupBuf.zAlloc, p, nNewSize);
+ }else{
+ u32 nSize = (u32)exprStructSize(p);
+ assert( (int)(sEdupBuf.zEnd - sEdupBuf.zAlloc) >=
+ (int)EXPR_FULLSIZE+nToken );
+ memcpy(sEdupBuf.zAlloc, p, nSize);
+ if( nSize<EXPR_FULLSIZE ){
+ memset(&sEdupBuf.zAlloc[nSize], 0, EXPR_FULLSIZE-nSize);
+ }
+ nNewSize = EXPR_FULLSIZE;
+ }
+
+ /* Set the EP_Reduced, EP_TokenOnly, and EP_Static flags appropriately. */
+ pNew->flags &= ~(EP_Reduced|EP_TokenOnly|EP_Static);
+ pNew->flags |= nStructSize & (EP_Reduced|EP_TokenOnly);
+ pNew->flags |= staticFlag;
+ ExprClearVVAProperties(pNew);
+ if( dupFlags ){
+ ExprSetVVAProperty(pNew, EP_Immutable);
+ }
+
+ /* Copy the p->u.zToken string, if any. */
+ assert( nToken>=0 );
+ if( nToken>0 ){
+ char *zToken = pNew->u.zToken = (char*)&sEdupBuf.zAlloc[nNewSize];
+ memcpy(zToken, p->u.zToken, nToken);
+ nNewSize += nToken;
+ }
+ sEdupBuf.zAlloc += ROUND8(nNewSize);
+
+ if( ((p->flags|pNew->flags)&(EP_TokenOnly|EP_Leaf))==0 ){
+
+ /* Fill in the pNew->x.pSelect or pNew->x.pList member. */
+ if( ExprUseXSelect(p) ){
+ pNew->x.pSelect = sqlite3SelectDup(db, p->x.pSelect, dupFlags);
+ }else{
+ pNew->x.pList = sqlite3ExprListDup(db, p->x.pList,
+ p->op!=TK_ORDER ? dupFlags : 0);
+ }
+
+#ifndef SQLITE_OMIT_WINDOWFUNC
+ if( ExprHasProperty(p, EP_WinFunc) ){
+ pNew->y.pWin = sqlite3WindowDup(db, pNew, p->y.pWin);
+ assert( ExprHasProperty(pNew, EP_WinFunc) );
+ }
+#endif /* SQLITE_OMIT_WINDOWFUNC */
+
+ /* Fill in pNew->pLeft and pNew->pRight. */
+ if( dupFlags ){
+ if( p->op==TK_SELECT_COLUMN ){
+ pNew->pLeft = p->pLeft;
+ assert( p->pRight==0
+ || p->pRight==p->pLeft
+ || ExprHasProperty(p->pLeft, EP_Subquery) );
+ }else{
+ pNew->pLeft = p->pLeft ?
+ exprDup(db, p->pLeft, EXPRDUP_REDUCE, &sEdupBuf) : 0;
+ }
+ pNew->pRight = p->pRight ?
+ exprDup(db, p->pRight, EXPRDUP_REDUCE, &sEdupBuf) : 0;
+ }else{
+ if( p->op==TK_SELECT_COLUMN ){
+ pNew->pLeft = p->pLeft;
+ assert( p->pRight==0
+ || p->pRight==p->pLeft
+ || ExprHasProperty(p->pLeft, EP_Subquery) );
+ }else{
+ pNew->pLeft = sqlite3ExprDup(db, p->pLeft, 0);
+ }
+ pNew->pRight = sqlite3ExprDup(db, p->pRight, 0);
+ }
+ }
+ }
+ if( pEdupBuf ) memcpy(pEdupBuf, &sEdupBuf, sizeof(sEdupBuf));
+ assert( sEdupBuf.zAlloc <= sEdupBuf.zEnd );
+ 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
+With *sqlite3WithDup(sqlite3 *db, With *p){
+ With *pRet = 0;
+ if( p ){
+ sqlite3_int64 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);
+ pRet->a[i].eM10d = p->a[i].eM10d;
+ }
+ }
+ }
+ return pRet;
+}
+#else
+# define sqlite3WithDup(x,y) 0
+#endif
+
+#ifndef SQLITE_OMIT_WINDOWFUNC
+/*
+** The gatherSelectWindows() procedure and its helper routine
+** gatherSelectWindowsCallback() are used to scan all the expressions
+** an a newly duplicated SELECT statement and gather all of the Window
+** objects found there, assembling them onto the linked list at Select->pWin.
+*/
+static int gatherSelectWindowsCallback(Walker *pWalker, Expr *pExpr){
+ if( pExpr->op==TK_FUNCTION && ExprHasProperty(pExpr, EP_WinFunc) ){
+ Select *pSelect = pWalker->u.pSelect;
+ Window *pWin = pExpr->y.pWin;
+ assert( pWin );
+ assert( IsWindowFunc(pExpr) );
+ assert( pWin->ppThis==0 );
+ sqlite3WindowLink(pSelect, pWin);
+ }
+ return WRC_Continue;
+}
+static int gatherSelectWindowsSelectCallback(Walker *pWalker, Select *p){
+ return p==pWalker->u.pSelect ? WRC_Continue : WRC_Prune;
+}
+static void gatherSelectWindows(Select *p){
+ Walker w;
+ w.xExprCallback = gatherSelectWindowsCallback;
+ w.xSelectCallback = gatherSelectWindowsSelectCallback;
+ w.xSelectCallback2 = 0;
+ w.pParse = 0;
+ w.u.pSelect = p;
+ sqlite3WalkSelect(&w, p);
+}
+#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, const Expr *p, int flags){
+ assert( flags==0 || flags==EXPRDUP_REDUCE );
+ return p ? exprDup(db, p, flags, 0) : 0;
+}
+ExprList *sqlite3ExprListDup(sqlite3 *db, const ExprList *p, int flags){
+ ExprList *pNew;
+ struct ExprList_item *pItem;
+ const struct ExprList_item *pOldItem;
+ int i;
+ Expr *pPriorSelectColOld = 0;
+ Expr *pPriorSelectColNew = 0;
+ assert( db!=0 );
+ if( p==0 ) return 0;
+ pNew = sqlite3DbMallocRawNN(db, sqlite3DbMallocSize(db, p));
+ if( pNew==0 ) return 0;
+ pNew->nExpr = p->nExpr;
+ pNew->nAlloc = p->nAlloc;
+ pItem = pNew->a;
+ pOldItem = p->a;
+ for(i=0; i<p->nExpr; i++, pItem++, pOldItem++){
+ Expr *pOldExpr = pOldItem->pExpr;
+ Expr *pNewExpr;
+ pItem->pExpr = sqlite3ExprDup(db, pOldExpr, flags);
+ if( pOldExpr
+ && pOldExpr->op==TK_SELECT_COLUMN
+ && (pNewExpr = pItem->pExpr)!=0
+ ){
+ if( pNewExpr->pRight ){
+ pPriorSelectColOld = pOldExpr->pRight;
+ pPriorSelectColNew = pNewExpr->pRight;
+ pNewExpr->pLeft = pNewExpr->pRight;
+ }else{
+ if( pOldExpr->pLeft!=pPriorSelectColOld ){
+ pPriorSelectColOld = pOldExpr->pLeft;
+ pPriorSelectColNew = sqlite3ExprDup(db, pPriorSelectColOld, flags);
+ pNewExpr->pRight = pPriorSelectColNew;
+ }
+ pNewExpr->pLeft = pPriorSelectColNew;
+ }
+ }
+ pItem->zEName = sqlite3DbStrDup(db, pOldItem->zEName);
+ pItem->fg = pOldItem->fg;
+ pItem->fg.done = 0;
+ 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, const 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++){
+ SrcItem *pNewItem = &pNew->a[i];
+ const SrcItem *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->u2 = pOldItem->u2;
+ if( pNewItem->fg.isCte ){
+ pNewItem->u2.pCteUse->nUse++;
+ }
+ if( pNewItem->fg.isTabFunc ){
+ pNewItem->u1.pFuncArg =
+ sqlite3ExprListDup(db, pOldItem->u1.pFuncArg, flags);
+ }
+ pTab = pNewItem->pTab = pOldItem->pTab;
+ if( pTab ){
+ pTab->nTabRef++;
+ }
+ pNewItem->pSelect = sqlite3SelectDup(db, pOldItem->pSelect, flags);
+ if( pOldItem->fg.isUsing ){
+ assert( pNewItem->fg.isUsing );
+ pNewItem->u3.pUsing = sqlite3IdListDup(db, pOldItem->u3.pUsing);
+ }else{
+ pNewItem->u3.pOn = sqlite3ExprDup(db, pOldItem->u3.pOn, flags);
+ }
+ pNewItem->colUsed = pOldItem->colUsed;
+ }
+ return pNew;
+}
+IdList *sqlite3IdListDup(sqlite3 *db, const IdList *p){
+ IdList *pNew;
+ int i;
+ assert( db!=0 );
+ if( p==0 ) return 0;
+ assert( p->eU4!=EU4_EXPR );
+ pNew = sqlite3DbMallocRawNN(db, sizeof(*pNew)+(p->nId-1)*sizeof(p->a[0]) );
+ if( pNew==0 ) return 0;
+ pNew->nId = p->nId;
+ pNew->eU4 = p->eU4;
+ for(i=0; i<p->nId; i++){
+ struct IdList_item *pNewItem = &pNew->a[i];
+ const struct IdList_item *pOldItem = &p->a[i];
+ pNewItem->zName = sqlite3DbStrDup(db, pOldItem->zName);
+ pNewItem->u4 = pOldItem->u4;
+ }
+ return pNew;
+}
+Select *sqlite3SelectDup(sqlite3 *db, const Select *pDup, int flags){
+ Select *pRet = 0;
+ Select *pNext = 0;
+ Select **pp = &pRet;
+ const Select *p;
+
+ assert( db!=0 );
+ for(p=pDup; p; p=p->pPrior){
+ Select *pNew = sqlite3DbMallocRawNN(db, sizeof(*p) );
+ if( pNew==0 ) break;
+ 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->pNext = pNext;
+ pNew->pPrior = 0;
+ pNew->pLimit = sqlite3ExprDup(db, p->pLimit, 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 = sqlite3WithDup(db, p->pWith);
+#ifndef SQLITE_OMIT_WINDOWFUNC
+ pNew->pWin = 0;
+ pNew->pWinDefn = sqlite3WindowListDup(db, p->pWinDefn);
+ if( p->pWin && db->mallocFailed==0 ) gatherSelectWindows(pNew);
+#endif
+ pNew->selId = p->selId;
+ if( db->mallocFailed ){
+ /* Any prior OOM might have left the Select object incomplete.
+ ** Delete the whole thing rather than allow an incomplete Select
+ ** to be used by the code generator. */
+ pNew->pNext = 0;
+ sqlite3SelectDelete(db, pNew);
+ break;
+ }
+ *pp = pNew;
+ pp = &pNew->pPrior;
+ pNext = pNew;
+ }
+
+ return pRet;
+}
+#else
+Select *sqlite3SelectDup(sqlite3 *db, const 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.
+**
+** The pList argument must be either NULL or a pointer to an ExprList
+** obtained from a prior call to sqlite3ExprListAppend().
+**
+** 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.
+*/
+static const struct ExprList_item zeroItem = {0};
+SQLITE_NOINLINE ExprList *sqlite3ExprListAppendNew(
+ sqlite3 *db, /* Database handle. Used for memory allocation */
+ Expr *pExpr /* Expression to be appended. Might be NULL */
+){
+ struct ExprList_item *pItem;
+ ExprList *pList;
+
+ pList = sqlite3DbMallocRawNN(db, sizeof(ExprList)+sizeof(pList->a[0])*4 );
+ if( pList==0 ){
+ sqlite3ExprDelete(db, pExpr);
+ return 0;
+ }
+ pList->nAlloc = 4;
+ pList->nExpr = 1;
+ pItem = &pList->a[0];
+ *pItem = zeroItem;
+ pItem->pExpr = pExpr;
+ return pList;
+}
+SQLITE_NOINLINE ExprList *sqlite3ExprListAppendGrow(
+ sqlite3 *db, /* Database handle. Used for memory allocation */
+ ExprList *pList, /* List to which to append. Might be NULL */
+ Expr *pExpr /* Expression to be appended. Might be NULL */
+){
+ struct ExprList_item *pItem;
+ ExprList *pNew;
+ pList->nAlloc *= 2;
+ pNew = sqlite3DbRealloc(db, pList,
+ sizeof(*pList)+(pList->nAlloc-1)*sizeof(pList->a[0]));
+ if( pNew==0 ){
+ sqlite3ExprListDelete(db, pList);
+ sqlite3ExprDelete(db, pExpr);
+ return 0;
+ }else{
+ pList = pNew;
+ }
+ pItem = &pList->a[pList->nExpr++];
+ *pItem = zeroItem;
+ pItem->pExpr = pExpr;
+ return pList;
+}
+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 */
+){
+ struct ExprList_item *pItem;
+ if( pList==0 ){
+ return sqlite3ExprListAppendNew(pParse->db,pExpr);
+ }
+ if( pList->nAlloc<pList->nExpr+1 ){
+ return sqlite3ExprListAppendGrow(pParse->db,pList,pExpr);
+ }
+ pItem = &pList->a[pList->nExpr++];
+ *pItem = zeroItem;
+ pItem->pExpr = pExpr;
+ return pList;
+}
+
+/*
+** pColumns and pExpr form a vector assignment which is part of the SET
+** clause of an UPDATE statement. Like this:
+**
+** (a,b,c) = (expr1,expr2,expr3)
+** Or: (a,b,c) = (SELECT x,y,z FROM ....)
+**
+** For each term of the vector assignment, append new entries to the
+** expression list pList. In the case of a subquery on the RHS, append
+** TK_SELECT_COLUMN expressions.
+*/
+ExprList *sqlite3ExprListAppendVector(
+ Parse *pParse, /* Parsing context */
+ ExprList *pList, /* List to which to append. Might be NULL */
+ IdList *pColumns, /* List of names of LHS of the assignment */
+ Expr *pExpr /* Vector expression to be appended. Might be NULL */
+){
+ sqlite3 *db = pParse->db;
+ int n;
+ int i;
+ int iFirst = pList ? pList->nExpr : 0;
+ /* pColumns can only be NULL due to an OOM but an OOM will cause an
+ ** exit prior to this routine being invoked */
+ if( NEVER(pColumns==0) ) goto vector_append_error;
+ if( pExpr==0 ) goto vector_append_error;
+
+ /* If the RHS is a vector, then we can immediately check to see that
+ ** the size of the RHS and LHS match. But if the RHS is a SELECT,
+ ** wildcards ("*") in the result set of the SELECT must be expanded before
+ ** we can do the size check, so defer the size check until code generation.
+ */
+ if( pExpr->op!=TK_SELECT && pColumns->nId!=(n=sqlite3ExprVectorSize(pExpr)) ){
+ sqlite3ErrorMsg(pParse, "%d columns assigned %d values",
+ pColumns->nId, n);
+ goto vector_append_error;
+ }
+
+ for(i=0; i<pColumns->nId; i++){
+ Expr *pSubExpr = sqlite3ExprForVectorField(pParse, pExpr, i, pColumns->nId);
+ assert( pSubExpr!=0 || db->mallocFailed );
+ if( pSubExpr==0 ) continue;
+ pList = sqlite3ExprListAppend(pParse, pList, pSubExpr);
+ if( pList ){
+ assert( pList->nExpr==iFirst+i+1 );
+ pList->a[pList->nExpr-1].zEName = pColumns->a[i].zName;
+ pColumns->a[i].zName = 0;
+ }
+ }
+
+ if( !db->mallocFailed && pExpr->op==TK_SELECT && ALWAYS(pList!=0) ){
+ Expr *pFirst = pList->a[iFirst].pExpr;
+ assert( pFirst!=0 );
+ assert( pFirst->op==TK_SELECT_COLUMN );
+
+ /* Store the SELECT statement in pRight so it will be deleted when
+ ** sqlite3ExprListDelete() is called */
+ pFirst->pRight = pExpr;
+ pExpr = 0;
+
+ /* Remember the size of the LHS in iTable so that we can check that
+ ** the RHS and LHS sizes match during code generation. */
+ pFirst->iTable = pColumns->nId;
+ }
+
+vector_append_error:
+ sqlite3ExprUnmapAndDelete(pParse, pExpr);
+ sqlite3IdListDelete(db, pColumns);
+ return pList;
+}
+
+/*
+** Set the sort order for the last element on the given ExprList.
+*/
+void sqlite3ExprListSetSortOrder(ExprList *p, int iSortOrder, int eNulls){
+ struct ExprList_item *pItem;
+ if( p==0 ) return;
+ assert( p->nExpr>0 );
+
+ assert( SQLITE_SO_UNDEFINED<0 && SQLITE_SO_ASC==0 && SQLITE_SO_DESC>0 );
+ assert( iSortOrder==SQLITE_SO_UNDEFINED
+ || iSortOrder==SQLITE_SO_ASC
+ || iSortOrder==SQLITE_SO_DESC
+ );
+ assert( eNulls==SQLITE_SO_UNDEFINED
+ || eNulls==SQLITE_SO_ASC
+ || eNulls==SQLITE_SO_DESC
+ );
+
+ pItem = &p->a[p->nExpr-1];
+ assert( pItem->fg.bNulls==0 );
+ if( iSortOrder==SQLITE_SO_UNDEFINED ){
+ iSortOrder = SQLITE_SO_ASC;
+ }
+ pItem->fg.sortFlags = (u8)iSortOrder;
+
+ if( eNulls!=SQLITE_SO_UNDEFINED ){
+ pItem->fg.bNulls = 1;
+ if( iSortOrder!=eNulls ){
+ pItem->fg.sortFlags |= KEYINFO_ORDER_BIGNULL;
+ }
+ }
+}
+
+/*
+** Set the ExprList.a[].zEName 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. */
+ const Token *pName, /* Name to be added */
+ int dequote /* True to cause the name to be dequoted */
+){
+ assert( pList!=0 || pParse->db->mallocFailed!=0 );
+ assert( pParse->eParseMode!=PARSE_MODE_UNMAP || dequote==0 );
+ if( pList ){
+ struct ExprList_item *pItem;
+ assert( pList->nExpr>0 );
+ pItem = &pList->a[pList->nExpr-1];
+ assert( pItem->zEName==0 );
+ assert( pItem->fg.eEName==ENAME_NAME );
+ pItem->zEName = sqlite3DbStrNDup(pParse->db, pName->z, pName->n);
+ if( dequote ){
+ /* If dequote==0, then pName->z does not point to part of a DDL
+ ** statement handled by the parser. And so no token need be added
+ ** to the token-map. */
+ sqlite3Dequote(pItem->zEName);
+ if( IN_RENAME_OBJECT ){
+ sqlite3RenameTokenMap(pParse, (const void*)pItem->zEName, pName);
+ }
+ }
+ }
+}
+
+/*
+** 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. */
+ const char *zStart, /* Start of the span */
+ const char *zEnd /* End of the span */
+){
+ 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 );
+ if( pItem->zEName==0 ){
+ pItem->zEName = sqlite3DbSpanDup(db, zStart, zEnd);
+ pItem->fg.eEName = ENAME_SPAN;
+ }
+ }
+}
+
+/*
+** 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.
+*/
+static SQLITE_NOINLINE void exprListDeleteNN(sqlite3 *db, ExprList *pList){
+ int i = pList->nExpr;
+ struct ExprList_item *pItem = pList->a;
+ assert( pList->nExpr>0 );
+ assert( db!=0 );
+ do{
+ sqlite3ExprDelete(db, pItem->pExpr);
+ if( pItem->zEName ) sqlite3DbNNFreeNN(db, pItem->zEName);
+ pItem++;
+ }while( --i>0 );
+ sqlite3DbNNFreeNN(db, pList);
+}
+void sqlite3ExprListDelete(sqlite3 *db, ExprList *pList){
+ if( pList ) exprListDeleteNN(db, pList);
+}
+void sqlite3ExprListDeleteGeneric(sqlite3 *db, void *pList){
+ if( ALWAYS(pList) ) exprListDeleteNN(db, (ExprList*)pList);
+}
+
+/*
+** Return the bitwise-OR of all Expr.flags fields in the given
+** ExprList.
+*/
+u32 sqlite3ExprListFlags(const ExprList *pList){
+ int i;
+ u32 m = 0;
+ assert( pList!=0 );
+ for(i=0; i<pList->nExpr; i++){
+ Expr *pExpr = pList->a[i].pExpr;
+ assert( pExpr!=0 );
+ m |= pExpr->flags;
+ }
+ return m;
+}
+
+/*
+** This is a SELECT-node callback for the expression walker that
+** always "fails". By "fail" in this case, we mean set
+** pWalker->eCode to zero and abort.
+**
+** This callback is used by multiple expression walkers.
+*/
+int sqlite3SelectWalkFail(Walker *pWalker, Select *NotUsed){
+ UNUSED_PARAMETER(NotUsed);
+ pWalker->eCode = 0;
+ return WRC_Abort;
+}
+
+/*
+** Check the input string to see if it is "true" or "false" (in any case).
+**
+** If the string is.... Return
+** "true" EP_IsTrue
+** "false" EP_IsFalse
+** anything else 0
+*/
+u32 sqlite3IsTrueOrFalse(const char *zIn){
+ if( sqlite3StrICmp(zIn, "true")==0 ) return EP_IsTrue;
+ if( sqlite3StrICmp(zIn, "false")==0 ) return EP_IsFalse;
+ return 0;
+}
+
+
+/*
+** If the input expression is an ID with the name "true" or "false"
+** then convert it into an TK_TRUEFALSE term. Return non-zero if
+** the conversion happened, and zero if the expression is unaltered.
+*/
+int sqlite3ExprIdToTrueFalse(Expr *pExpr){
+ u32 v;
+ assert( pExpr->op==TK_ID || pExpr->op==TK_STRING );
+ if( !ExprHasProperty(pExpr, EP_Quoted|EP_IntValue)
+ && (v = sqlite3IsTrueOrFalse(pExpr->u.zToken))!=0
+ ){
+ pExpr->op = TK_TRUEFALSE;
+ ExprSetProperty(pExpr, v);
+ return 1;
+ }
+ return 0;
+}
+
+/*
+** The argument must be a TK_TRUEFALSE Expr node. Return 1 if it is TRUE
+** and 0 if it is FALSE.
+*/
+int sqlite3ExprTruthValue(const Expr *pExpr){
+ pExpr = sqlite3ExprSkipCollateAndLikely((Expr*)pExpr);
+ assert( pExpr->op==TK_TRUEFALSE );
+ assert( !ExprHasProperty(pExpr, EP_IntValue) );
+ assert( sqlite3StrICmp(pExpr->u.zToken,"true")==0
+ || sqlite3StrICmp(pExpr->u.zToken,"false")==0 );
+ return pExpr->u.zToken[4]==0;
+}
+
+/*
+** If pExpr is an AND or OR expression, try to simplify it by eliminating
+** terms that are always true or false. Return the simplified expression.
+** Or return the original expression if no simplification is possible.
+**
+** Examples:
+**
+** (x<10) AND true => (x<10)
+** (x<10) AND false => false
+** (x<10) AND (y=22 OR false) => (x<10) AND (y=22)
+** (x<10) AND (y=22 OR true) => (x<10)
+** (y=22) OR true => true
+*/
+Expr *sqlite3ExprSimplifiedAndOr(Expr *pExpr){
+ assert( pExpr!=0 );
+ if( pExpr->op==TK_AND || pExpr->op==TK_OR ){
+ Expr *pRight = sqlite3ExprSimplifiedAndOr(pExpr->pRight);
+ Expr *pLeft = sqlite3ExprSimplifiedAndOr(pExpr->pLeft);
+ if( ExprAlwaysTrue(pLeft) || ExprAlwaysFalse(pRight) ){
+ pExpr = pExpr->op==TK_AND ? pRight : pLeft;
+ }else if( ExprAlwaysTrue(pRight) || ExprAlwaysFalse(pLeft) ){
+ pExpr = pExpr->op==TK_AND ? pLeft : pRight;
+ }
+ }
+ return pExpr;
+}
+
+
+/*
+** 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 DEFAULT
+** expressions in a CREATE TABLE statement. The Walker.eCode value is 5
+** when parsing an existing schema out of the sqlite_schema table and 4
+** when processing a new CREATE TABLE statement. A bound parameter raises
+** an error for new statements, but is silently converted
+** to NULL for existing schemas. This allows sqlite_schema 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 an outer join disqualifies the expression
+ ** from being considered constant. */
+ if( pWalker->eCode==2 && ExprHasProperty(pExpr, EP_OuterON) ){
+ 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))
+ && !ExprHasProperty(pExpr, EP_WinFunc)
+ ){
+ if( pWalker->eCode==5 ) ExprSetProperty(pExpr, EP_FromDDL);
+ return WRC_Continue;
+ }else{
+ pWalker->eCode = 0;
+ return WRC_Abort;
+ }
+ case TK_ID:
+ /* Convert "true" or "false" in a DEFAULT clause into the
+ ** appropriate TK_TRUEFALSE operator */
+ if( sqlite3ExprIdToTrueFalse(pExpr) ){
+ return WRC_Prune;
+ }
+ /* no break */ deliberate_fall_through
+ 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( ExprHasProperty(pExpr, EP_FixedCol) && pWalker->eCode!=2 ){
+ return WRC_Continue;
+ }
+ if( pWalker->eCode==3 && pExpr->iTable==pWalker->u.iCur ){
+ return WRC_Continue;
+ }
+ /* no break */ deliberate_fall_through
+ case TK_IF_NULL_ROW:
+ case TK_REGISTER:
+ case TK_DOT:
+ testcase( pExpr->op==TK_REGISTER );
+ testcase( pExpr->op==TK_IF_NULL_ROW );
+ testcase( pExpr->op==TK_DOT );
+ 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_schema 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;
+ }
+ /* no break */ deliberate_fall_through
+ default:
+ testcase( pExpr->op==TK_SELECT ); /* sqlite3SelectWalkFail() disallows */
+ testcase( pExpr->op==TK_EXISTS ); /* sqlite3SelectWalkFail() disallows */
+ return WRC_Continue;
+ }
+}
+static int exprIsConst(Expr *p, int initFlag, int iCur){
+ Walker w;
+ w.eCode = initFlag;
+ w.xExprCallback = exprNodeIsConstant;
+ w.xSelectCallback = sqlite3SelectWalkFail;
+#ifdef SQLITE_DEBUG
+ w.xSelectCallback2 = sqlite3SelectWalkAssert2;
+#endif
+ 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
+**
+** (1) the expression is constant, and
+** (2) the expression does originate in the ON or USING clause
+** of a LEFT JOIN, and
+** (3) the expression does not contain any EP_FixedCol TK_COLUMN
+** operands created by the constant propagation optimization.
+**
+** When this routine returns true, it indicates that the expression
+** can be added to the pParse->pConstExpr list and evaluated once when
+** the prepared statement starts up. See sqlite3ExprCodeRunJustOnce().
+*/
+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);
+}
+
+/*
+** Check pExpr to see if it is an constraint on the single data source
+** pSrc = &pSrcList->a[iSrc]. In other words, check to see if pExpr
+** constrains pSrc but does not depend on any other tables or data
+** sources anywhere else in the query. Return true (non-zero) if pExpr
+** is a constraint on pSrc only.
+**
+** This is an optimization. False negatives will perhaps cause slower
+** queries, but false positives will yield incorrect answers. So when in
+** doubt, return 0.
+**
+** To be an single-source constraint, the following must be true:
+**
+** (1) pExpr cannot refer to any table other than pSrc->iCursor.
+**
+** (2) pExpr cannot use subqueries or non-deterministic functions.
+**
+** (3) pSrc cannot be part of the left operand for a RIGHT JOIN.
+** (Is there some way to relax this constraint?)
+**
+** (4) If pSrc is the right operand of a LEFT JOIN, then...
+** (4a) pExpr must come from an ON clause..
+** (4b) and specifically the ON clause associated with the LEFT JOIN.
+**
+** (5) If pSrc is not the right operand of a LEFT JOIN or the left
+** operand of a RIGHT JOIN, then pExpr must be from the WHERE
+** clause, not an ON clause.
+**
+** (6) Either:
+**
+** (6a) pExpr does not originate in an ON or USING clause, or
+**
+** (6b) The ON or USING clause from which pExpr is derived is
+** not to the left of a RIGHT JOIN (or FULL JOIN).
+**
+** Without this restriction, accepting pExpr as a single-table
+** constraint might move the the ON/USING filter expression
+** from the left side of a RIGHT JOIN over to the right side,
+** which leads to incorrect answers. See also restriction (9)
+** on push-down.
+*/
+int sqlite3ExprIsSingleTableConstraint(
+ Expr *pExpr, /* The constraint */
+ const SrcList *pSrcList, /* Complete FROM clause */
+ int iSrc /* Which element of pSrcList to use */
+){
+ const SrcItem *pSrc = &pSrcList->a[iSrc];
+ if( pSrc->fg.jointype & JT_LTORJ ){
+ return 0; /* rule (3) */
+ }
+ if( pSrc->fg.jointype & JT_LEFT ){
+ if( !ExprHasProperty(pExpr, EP_OuterON) ) return 0; /* rule (4a) */
+ if( pExpr->w.iJoin!=pSrc->iCursor ) return 0; /* rule (4b) */
+ }else{
+ if( ExprHasProperty(pExpr, EP_OuterON) ) return 0; /* rule (5) */
+ }
+ if( ExprHasProperty(pExpr, EP_OuterON|EP_InnerON) /* (6a) */
+ && (pSrcList->a[0].fg.jointype & JT_LTORJ)!=0 /* Fast pre-test of (6b) */
+ ){
+ int jj;
+ for(jj=0; jj<iSrc; jj++){
+ if( pExpr->w.iJoin==pSrcList->a[jj].iCursor ){
+ if( (pSrcList->a[jj].fg.jointype & JT_LTORJ)!=0 ){
+ return 0; /* restriction (6) */
+ }
+ break;
+ }
+ }
+ }
+ return sqlite3ExprIsTableConstant(pExpr, pSrc->iCursor); /* rules (1), (2) */
+}
+
+
+/*
+** sqlite3WalkExpr() callback used by sqlite3ExprIsConstantOrGroupBy().
+*/
+static int exprNodeIsConstantOrGroupBy(Walker *pWalker, Expr *pExpr){
+ ExprList *pGroupBy = pWalker->u.pGroupBy;
+ int i;
+
+ /* Check if pExpr is identical to any GROUP BY term. If so, consider
+ ** it constant. */
+ for(i=0; i<pGroupBy->nExpr; i++){
+ Expr *p = pGroupBy->a[i].pExpr;
+ if( sqlite3ExprCompare(0, pExpr, p, -1)<2 ){
+ CollSeq *pColl = sqlite3ExprNNCollSeq(pWalker->pParse, p);
+ if( sqlite3IsBinary(pColl) ){
+ return WRC_Prune;
+ }
+ }
+ }
+
+ /* Check if pExpr is a sub-select. If so, consider it variable. */
+ if( ExprUseXSelect(pExpr) ){
+ pWalker->eCode = 0;
+ return WRC_Abort;
+ }
+
+ return exprNodeIsConstant(pWalker, pExpr);
+}
+
+/*
+** Walk the expression tree passed as the first argument. Return non-zero
+** if the expression consists entirely of constants or copies of terms
+** in pGroupBy that sort with the BINARY collation sequence.
+**
+** This routine is used to determine if a term of the HAVING clause can
+** be promoted into the WHERE clause. In order for such a promotion to work,
+** the value of the HAVING clause term must be the same for all members of
+** a "group". The requirement that the GROUP BY term must be BINARY
+** assumes that no other collating sequence will have a finer-grained
+** grouping than binary. In other words (A=B COLLATE binary) implies
+** A=B in every other collating sequence. The requirement that the
+** GROUP BY be BINARY is stricter than necessary. It would also work
+** to promote HAVING clauses that use the same alternative collating
+** sequence as the GROUP BY term, but that is much harder to check,
+** alternative collating sequences are uncommon, and this is only an
+** optimization, so we take the easy way out and simply require the
+** GROUP BY to use the BINARY collating sequence.
+*/
+int sqlite3ExprIsConstantOrGroupBy(Parse *pParse, Expr *p, ExprList *pGroupBy){
+ Walker w;
+ w.eCode = 1;
+ w.xExprCallback = exprNodeIsConstantOrGroupBy;
+ w.xSelectCallback = 0;
+ w.u.pGroupBy = pGroupBy;
+ w.pParse = pParse;
+ sqlite3WalkExpr(&w, p);
+ return w.eCode;
+}
+
+/*
+** Walk an expression tree for the DEFAULT field of a column definition
+** in a CREATE TABLE statement. Return non-zero if the expression is
+** acceptable for use as a DEFAULT. That is to say, return non-zero if
+** the expression is constant or a function call with constant arguments.
+** Return and 0 if there are any variables.
+**
+** isInit is true when parsing from sqlite_schema. isInit is false when
+** processing a new CREATE TABLE statement. When isInit is true, parameters
+** (such as ? or $abc) in the expression are converted into NULL. When
+** isInit is false, parameters raise an error. Parameters should not be
+** allowed in a CREATE TABLE statement, but some legacy versions of SQLite
+** allowed it, so we need to support it when reading sqlite_schema for
+** backwards compatibility.
+**
+** If isInit is true, set EP_FromDDL on every TK_FUNCTION node.
+**
+** 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;
+ w.eCode = 1;
+ w.xExprCallback = sqlite3ExprWalkNoop;
+ w.xSelectCallback = sqlite3SelectWalkFail;
+#ifdef SQLITE_DEBUG
+ w.xSelectCallback2 = sqlite3SelectWalkAssert2;
+#endif
+ 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(const Expr *p, int *pValue){
+ int rc = 0;
+ if( NEVER(p==0) ) return 0; /* Used to only happen following on OOM */
+
+ /* 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 = 0;
+ if( sqlite3ExprIsInteger(p->pLeft, &v) ){
+ assert( ((unsigned int)v)!=0x80000000 );
+ *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;
+ assert( p!=0 );
+ while( p->op==TK_UPLUS || p->op==TK_UMINUS ){
+ p = p->pLeft;
+ assert( p!=0 );
+ }
+ 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( ExprUseYTab(p) );
+ return ExprHasProperty(p, EP_CanBeNull) ||
+ NEVER(p->y.pTab==0) || /* Reference to column of index on expr */
+ (p->iColumn>=0
+ && p->y.pTab->aCol!=0 /* Possible due to prior error */
+ && ALWAYS(p->iColumn<p->y.pTab->nCol)
+ && p->y.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;
+ int unaryMinus = 0;
+ if( aff==SQLITE_AFF_BLOB ) return 1;
+ while( p->op==TK_UPLUS || p->op==TK_UMINUS ){
+ if( p->op==TK_UMINUS ) unaryMinus = 1;
+ p = p->pLeft;
+ }
+ op = p->op;
+ if( op==TK_REGISTER ) op = p->op2;
+ switch( op ){
+ case TK_INTEGER: {
+ return aff>=SQLITE_AFF_NUMERIC;
+ }
+ case TK_FLOAT: {
+ return aff>=SQLITE_AFF_NUMERIC;
+ }
+ case TK_STRING: {
+ return !unaryMinus && aff==SQLITE_AFF_TEXT;
+ }
+ case TK_BLOB: {
+ return !unaryMinus;
+ }
+ case TK_COLUMN: {
+ assert( p->iTable>=0 ); /* p cannot be part of a CHECK constraint */
+ return aff>=SQLITE_AFF_NUMERIC && p->iColumn<0;
+ }
+ 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 a pointer to a buffer containing a usable rowid alias for table
+** pTab. An alias is usable if there is not an explicit user-defined column
+** of the same name.
+*/
+const char *sqlite3RowidAlias(Table *pTab){
+ const char *azOpt[] = {"_ROWID_", "ROWID", "OID"};
+ int ii;
+ assert( VisibleRowid(pTab) );
+ for(ii=0; ii<ArraySize(azOpt); ii++){
+ int iCol;
+ for(iCol=0; iCol<pTab->nCol; iCol++){
+ if( sqlite3_stricmp(azOpt[ii], pTab->aCol[iCol].zCnName)==0 ) break;
+ }
+ if( iCol==pTab->nCol ){
+ return azOpt[ii];
+ }
+ }
+ return 0;
+}
+
+/*
+** pX is the RHS of an IN operator. If pX is a SELECT statement
+** that can be simplified to a direct table access, then return
+** a pointer to the SELECT statement. If pX is not a SELECT statement,
+** or if the SELECT statement needs to be materialized into a transient
+** table, then return NULL.
+*/
+#ifndef SQLITE_OMIT_SUBQUERY
+static Select *isCandidateForInOpt(const Expr *pX){
+ Select *p;
+ SrcList *pSrc;
+ ExprList *pEList;
+ Table *pTab;
+ int i;
+ if( !ExprUseXSelect(pX) ) return 0; /* Not a subquery */
+ if( ExprHasProperty(pX, EP_VarSelect) ) return 0; /* Correlated subq */
+ p = pX->x.pSelect;
+ 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 */
+ 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;
+ assert( pTab!=0 );
+ assert( !IsView(pTab) ); /* FROM clause is not a view */
+ if( IsVirtual(pTab) ) return 0; /* FROM clause not a virtual table */
+ pEList = p->pEList;
+ assert( pEList!=0 );
+ /* All SELECT results must be columns. */
+ for(i=0; i<pEList->nExpr; i++){
+ Expr *pRes = pEList->a[i].pExpr;
+ if( pRes->op!=TK_COLUMN ) return 0;
+ assert( pRes->iTable==pSrc->a[0].iCursor ); /* Not a correlated subquery */
+ }
+ return p;
+}
+#endif /* SQLITE_OMIT_SUBQUERY */
+
+#ifndef SQLITE_OMIT_SUBQUERY
+/*
+** 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);
+}
+#endif
+
+
+#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 the *piTab parameter 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 ephemeral 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 <column1>, <column2>... 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. In this case, the creation and initialization of the
+** ephemeral table might be put inside of a subroutine, the EP_Subrtn flag
+** will be set on pX and the pX->y.sub fields will be set to show where
+** the subroutine is coded.
+**
+** The inFlags parameter must contain, at a minimum, one of the bits
+** IN_INDEX_MEMBERSHIP or IN_INDEX_LOOP but not both. 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 ephemeral table will be created unless the selected columns are guaranteed
+** to be unique - either because it is an INTEGER PRIMARY KEY or due to
+** a UNIQUE constraint or index.
+**
+** When IN_INDEX_MEMBERSHIP is used (and the b-tree will be used
+** for fast set membership tests) then an ephemeral table must
+** be used unless <columns> is a single INTEGER PRIMARY KEY column or an
+** index can be found with the specified <columns> as its left-most.
+**
+** 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.
+**
+** If the aiMap parameter is not NULL, it must point to an array containing
+** one element for each column returned by the SELECT statement on the RHS
+** of the IN(...) operator. The i'th entry of the array is populated with the
+** offset of the index column that matches the i'th column returned by the
+** SELECT. For example, if the expression and selected index are:
+**
+** (?,?,?) IN (SELECT a, b, c FROM t1)
+** CREATE INDEX i1 ON t1(b, c, a);
+**
+** then aiMap[] is populated with {2, 0, 1}.
+*/
+#ifndef SQLITE_OMIT_SUBQUERY
+int sqlite3FindInIndex(
+ Parse *pParse, /* Parsing context */
+ Expr *pX, /* The IN expression */
+ u32 inFlags, /* IN_INDEX_LOOP, _MEMBERSHIP, and/or _NOOP_OK */
+ int *prRhsHasNull, /* Register holding NULL status. See notes */
+ int *aiMap, /* Mapping from Index fields to RHS fields */
+ int *piTab /* OUT: index to use */
+){
+ Select *p; /* SELECT to the right of IN operator */
+ int eType = 0; /* Type of RHS table. IN_INDEX_* */
+ int iTab; /* 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;
+ iTab = pParse->nTab++;
+
+ /* If the RHS of this IN(...) operator is a SELECT, and if it matters
+ ** whether or not the SELECT result contains NULL values, check whether
+ ** or not NULL is actually possible (it may not be, for example, due
+ ** to NOT NULL constraints in the schema). If no NULL values are possible,
+ ** set prRhsHasNull to 0 before continuing. */
+ if( prRhsHasNull && ExprUseXSelect(pX) ){
+ int i;
+ ExprList *pEList = pX->x.pSelect->pEList;
+ for(i=0; i<pEList->nExpr; i++){
+ if( sqlite3ExprCanBeNull(pEList->a[i].pExpr) ) break;
+ }
+ if( i==pEList->nExpr ){
+ prRhsHasNull = 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. */
+ if( pParse->nErr==0 && (p = isCandidateForInOpt(pX))!=0 ){
+ sqlite3 *db = pParse->db; /* Database connection */
+ Table *pTab; /* Table <table>. */
+ int iDb; /* Database idx for pTab */
+ ExprList *pEList = p->pEList;
+ int nExpr = pEList->nExpr;
+
+ 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;
+
+ /* Code an OP_Transaction and OP_TableLock for <table>. */
+ iDb = sqlite3SchemaToIndex(db, pTab->pSchema);
+ assert( iDb>=0 && iDb<SQLITE_MAX_DB );
+ sqlite3CodeVerifySchema(pParse, iDb);
+ sqlite3TableLock(pParse, iDb, pTab->tnum, 0, pTab->zName);
+
+ assert(v); /* sqlite3GetVdbe() has always been previously called */
+ if( nExpr==1 && pEList->a[0].pExpr->iColumn<0 ){
+ /* The "x IN (SELECT rowid FROM table)" case */
+ int iAddr = sqlite3VdbeAddOp0(v, OP_Once);
+ VdbeCoverage(v);
+
+ sqlite3OpenTable(pParse, iTab, iDb, pTab, OP_OpenRead);
+ eType = IN_INDEX_ROWID;
+ ExplainQueryPlan((pParse, 0,
+ "USING ROWID SEARCH ON TABLE %s FOR IN-OPERATOR",pTab->zName));
+ sqlite3VdbeJumpHere(v, iAddr);
+ }else{
+ Index *pIdx; /* Iterator variable */
+ int affinity_ok = 1;
+ int i;
+
+ /* Check that the affinity that will be used to perform each
+ ** comparison is the same as the affinity of each column in table
+ ** on the RHS of the IN operator. If it not, it is not possible to
+ ** use any index of the RHS table. */
+ for(i=0; i<nExpr && affinity_ok; i++){
+ Expr *pLhs = sqlite3VectorFieldSubexpr(pX->pLeft, i);
+ int iCol = pEList->a[i].pExpr->iColumn;
+ char idxaff = sqlite3TableColumnAffinity(pTab,iCol); /* RHS table */
+ char cmpaff = sqlite3CompareAffinity(pLhs, idxaff);
+ testcase( cmpaff==SQLITE_AFF_BLOB );
+ testcase( cmpaff==SQLITE_AFF_TEXT );
+ switch( cmpaff ){
+ case SQLITE_AFF_BLOB:
+ break;
+ case SQLITE_AFF_TEXT:
+ /* sqlite3CompareAffinity() only returns TEXT if one side or the
+ ** other has no affinity and the other side is TEXT. Hence,
+ ** the only way for cmpaff to be TEXT is for idxaff to be TEXT
+ ** and for the term on the LHS of the IN to have no affinity. */
+ assert( idxaff==SQLITE_AFF_TEXT );
+ break;
+ default:
+ affinity_ok = sqlite3IsNumericAffinity(idxaff);
+ }
+ }
+
+ if( affinity_ok ){
+ /* Search for an existing index that will work for this IN operator */
+ for(pIdx=pTab->pIndex; pIdx && eType==0; pIdx=pIdx->pNext){
+ Bitmask colUsed; /* Columns of the index used */
+ Bitmask mCol; /* Mask for the current column */
+ if( pIdx->nColumn<nExpr ) continue;
+ if( pIdx->pPartIdxWhere!=0 ) continue;
+ /* Maximum nColumn is BMS-2, not BMS-1, so that we can compute
+ ** BITMASK(nExpr) without overflowing */
+ testcase( pIdx->nColumn==BMS-2 );
+ testcase( pIdx->nColumn==BMS-1 );
+ if( pIdx->nColumn>=BMS-1 ) continue;
+ if( mustBeUnique ){
+ if( pIdx->nKeyCol>nExpr
+ ||(pIdx->nColumn>nExpr && !IsUniqueIndex(pIdx))
+ ){
+ continue; /* This index is not unique over the IN RHS columns */
+ }
+ }
+
+ colUsed = 0; /* Columns of index used so far */
+ for(i=0; i<nExpr; i++){
+ Expr *pLhs = sqlite3VectorFieldSubexpr(pX->pLeft, i);
+ Expr *pRhs = pEList->a[i].pExpr;
+ CollSeq *pReq = sqlite3BinaryCompareCollSeq(pParse, pLhs, pRhs);
+ int j;
+
+ for(j=0; j<nExpr; j++){
+ if( pIdx->aiColumn[j]!=pRhs->iColumn ) continue;
+ assert( pIdx->azColl[j] );
+ if( pReq!=0 && sqlite3StrICmp(pReq->zName, pIdx->azColl[j])!=0 ){
+ continue;
+ }
+ break;
+ }
+ if( j==nExpr ) break;
+ mCol = MASKBIT(j);
+ if( mCol & colUsed ) break; /* Each column used only once */
+ colUsed |= mCol;
+ if( aiMap ) aiMap[i] = j;
+ }
+
+ assert( i==nExpr || colUsed!=(MASKBIT(nExpr)-1) );
+ if( colUsed==(MASKBIT(nExpr)-1) ){
+ /* If we reach this point, that means the index pIdx is usable */
+ int iAddr = sqlite3VdbeAddOp0(v, OP_Once); VdbeCoverage(v);
+ ExplainQueryPlan((pParse, 0,
+ "USING INDEX %s FOR IN-OPERATOR",pIdx->zName));
+ 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 ){
+#ifdef SQLITE_ENABLE_COLUMN_USED_MASK
+ i64 mask = (1<<nExpr)-1;
+ sqlite3VdbeAddOp4Dup8(v, OP_ColumnsUsed,
+ iTab, 0, 0, (u8*)&mask, P4_INT64);
+#endif
+ *prRhsHasNull = ++pParse->nMem;
+ if( nExpr==1 ){
+ sqlite3SetHasNullFlag(v, iTab, *prRhsHasNull);
+ }
+ }
+ sqlite3VdbeJumpHere(v, iAddr);
+ }
+ } /* End loop over indexes */
+ } /* End if( affinity_ok ) */
+ } /* End if not an rowid index */
+ } /* End attempt to optimize using an index */
+
+ /* 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 constant 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)
+ && ExprUseXList(pX)
+ && (!sqlite3InRhsIsConstant(pX) || pX->x.pList->nExpr<=2)
+ ){
+ pParse->nTab--; /* Back out the allocation of the unused cursor */
+ iTab = -1; /* Cursor is not allocated */
+ 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;
+ }else if( prRhsHasNull ){
+ *prRhsHasNull = rMayHaveNull = ++pParse->nMem;
+ }
+ assert( pX->op==TK_IN );
+ sqlite3CodeRhsOfIN(pParse, pX, iTab);
+ if( rMayHaveNull ){
+ sqlite3SetHasNullFlag(v, iTab, rMayHaveNull);
+ }
+ pParse->nQueryLoop = savedNQueryLoop;
+ }
+
+ if( aiMap && eType!=IN_INDEX_INDEX_ASC && eType!=IN_INDEX_INDEX_DESC ){
+ int i, n;
+ n = sqlite3ExprVectorSize(pX->pLeft);
+ for(i=0; i<n; i++) aiMap[i] = i;
+ }
+ *piTab = iTab;
+ return eType;
+}
+#endif
+
+#ifndef SQLITE_OMIT_SUBQUERY
+/*
+** Argument pExpr is an (?, ?...) IN(...) expression. This
+** function allocates and returns a nul-terminated string containing
+** the affinities to be used for each column of the comparison.
+**
+** It is the responsibility of the caller to ensure that the returned
+** string is eventually freed using sqlite3DbFree().
+*/
+static char *exprINAffinity(Parse *pParse, const Expr *pExpr){
+ Expr *pLeft = pExpr->pLeft;
+ int nVal = sqlite3ExprVectorSize(pLeft);
+ Select *pSelect = ExprUseXSelect(pExpr) ? pExpr->x.pSelect : 0;
+ char *zRet;
+
+ assert( pExpr->op==TK_IN );
+ zRet = sqlite3DbMallocRaw(pParse->db, nVal+1);
+ if( zRet ){
+ int i;
+ for(i=0; i<nVal; i++){
+ Expr *pA = sqlite3VectorFieldSubexpr(pLeft, i);
+ char a = sqlite3ExprAffinity(pA);
+ if( pSelect ){
+ zRet[i] = sqlite3CompareAffinity(pSelect->pEList->a[i].pExpr, a);
+ }else{
+ zRet[i] = a;
+ }
+ }
+ zRet[nVal] = '\0';
+ }
+ return zRet;
+}
+#endif
+
+#ifndef SQLITE_OMIT_SUBQUERY
+/*
+** Load the Parse object passed as the first argument with an error
+** message of the form:
+**
+** "sub-select returns N columns - expected M"
+*/
+void sqlite3SubselectError(Parse *pParse, int nActual, int nExpect){
+ if( pParse->nErr==0 ){
+ const char *zFmt = "sub-select returns %d columns - expected %d";
+ sqlite3ErrorMsg(pParse, zFmt, nActual, nExpect);
+ }
+}
+#endif
+
+/*
+** Expression pExpr is a vector that has been used in a context where
+** it is not permitted. If pExpr is a sub-select vector, this routine
+** loads the Parse object with a message of the form:
+**
+** "sub-select returns N columns - expected 1"
+**
+** Or, if it is a regular scalar vector:
+**
+** "row value misused"
+*/
+void sqlite3VectorErrorMsg(Parse *pParse, Expr *pExpr){
+#ifndef SQLITE_OMIT_SUBQUERY
+ if( ExprUseXSelect(pExpr) ){
+ sqlite3SubselectError(pParse, pExpr->x.pSelect->pEList->nExpr, 1);
+ }else
+#endif
+ {
+ sqlite3ErrorMsg(pParse, "row value misused");
+ }
+}
+
+#ifndef SQLITE_OMIT_SUBQUERY
+/*
+** 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:
+**
+** 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 is the IN operator. The cursor number for the
+** constructed ephemeral table is returned. The first time the ephemeral
+** table is computed, the cursor number is also stored in pExpr->iTable,
+** however the cursor number returned might not be the same, as it might
+** have been duplicated using OP_OpenDup.
+**
+** 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.
+*/
+void sqlite3CodeRhsOfIN(
+ Parse *pParse, /* Parsing context */
+ Expr *pExpr, /* The IN operator */
+ int iTab /* Use this cursor number */
+){
+ int addrOnce = 0; /* Address of the OP_Once instruction at top */
+ 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 = pParse->pVdbe;
+ assert( v!=0 );
+
+ /* The evaluation of the IN 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 compute the RHS just once
+ ** and reuse it many names.
+ */
+ if( !ExprHasProperty(pExpr, EP_VarSelect) && pParse->iSelfTab==0 ){
+ /* Reuse of the RHS is allowed */
+ /* If this routine has already been coded, but the previous code
+ ** might not have been invoked yet, so invoke it now as a subroutine.
+ */
+ if( ExprHasProperty(pExpr, EP_Subrtn) ){
+ addrOnce = sqlite3VdbeAddOp0(v, OP_Once); VdbeCoverage(v);
+ if( ExprUseXSelect(pExpr) ){
+ ExplainQueryPlan((pParse, 0, "REUSE LIST SUBQUERY %d",
+ pExpr->x.pSelect->selId));
+ }
+ assert( ExprUseYSub(pExpr) );
+ sqlite3VdbeAddOp2(v, OP_Gosub, pExpr->y.sub.regReturn,
+ pExpr->y.sub.iAddr);
+ assert( iTab!=pExpr->iTable );
+ sqlite3VdbeAddOp2(v, OP_OpenDup, iTab, pExpr->iTable);
+ sqlite3VdbeJumpHere(v, addrOnce);
+ return;
+ }
+
+ /* Begin coding the subroutine */
+ assert( !ExprUseYWin(pExpr) );
+ ExprSetProperty(pExpr, EP_Subrtn);
+ assert( !ExprHasProperty(pExpr, EP_TokenOnly|EP_Reduced) );
+ pExpr->y.sub.regReturn = ++pParse->nMem;
+ pExpr->y.sub.iAddr =
+ sqlite3VdbeAddOp2(v, OP_BeginSubrtn, 0, pExpr->y.sub.regReturn) + 1;
+
+ addrOnce = sqlite3VdbeAddOp0(v, OP_Once); VdbeCoverage(v);
+ }
+
+ /* Check to see if this is a vector IN operator */
+ pLeft = pExpr->pLeft;
+ nVal = sqlite3ExprVectorSize(pLeft);
+
+ /* Construct the ephemeral table that will contain the content of
+ ** RHS of the IN operator.
+ */
+ pExpr->iTable = iTab;
+ addr = sqlite3VdbeAddOp2(v, OP_OpenEphemeral, pExpr->iTable, nVal);
+#ifdef SQLITE_ENABLE_EXPLAIN_COMMENTS
+ if( ExprUseXSelect(pExpr) ){
+ VdbeComment((v, "Result of SELECT %u", pExpr->x.pSelect->selId));
+ }else{
+ VdbeComment((v, "RHS of IN operator"));
+ }
+#endif
+ pKeyInfo = sqlite3KeyInfoAlloc(pParse->db, nVal, 1);
+
+ if( ExprUseXSelect(pExpr) ){
+ /* 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 %d",
+ addrOnce?"":"CORRELATED ", pSelect->selId
+ ));
+ /* 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) ){
+ Select *pCopy;
+ SelectDest dest;
+ int i;
+ int rc;
+ sqlite3SelectDestInit(&dest, SRT_Set, iTab);
+ dest.zAffSdst = exprINAffinity(pParse, pExpr);
+ pSelect->iLimit = 0;
+ testcase( pSelect->selFlags & SF_Distinct );
+ testcase( pKeyInfo==0 ); /* Caused by OOM in sqlite3KeyInfoAlloc() */
+ pCopy = sqlite3SelectDup(pParse->db, pSelect, 0);
+ rc = pParse->db->mallocFailed ? 1 :sqlite3Select(pParse, pCopy, &dest);
+ sqlite3SelectDelete(pParse->db, pCopy);
+ sqlite3DbFree(pParse->db, dest.zAffSdst);
+ if( rc ){
+ sqlite3KeyInfoUnref(pKeyInfo);
+ return;
+ }
+ 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;
+ affinity = sqlite3ExprAffinity(pLeft);
+ if( affinity<=SQLITE_AFF_NONE ){
+ affinity = SQLITE_AFF_BLOB;
+ }else if( affinity==SQLITE_AFF_REAL ){
+ affinity = SQLITE_AFF_NUMERIC;
+ }
+ if( pKeyInfo ){
+ assert( sqlite3KeyInfoIsWriteable(pKeyInfo) );
+ pKeyInfo->aColl[0] = sqlite3ExprCollSeq(pParse, pExpr->pLeft);
+ }
+
+ /* Loop through each expression in <exprlist>. */
+ r1 = sqlite3GetTempReg(pParse);
+ r2 = sqlite3GetTempReg(pParse);
+ for(i=pList->nExpr, pItem=pList->a; i>0; i--, pItem++){
+ Expr *pE2 = pItem->pExpr;
+
+ /* 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( addrOnce && !sqlite3ExprIsConstant(pE2) ){
+ sqlite3VdbeChangeToNoop(v, addrOnce-1);
+ sqlite3VdbeChangeToNoop(v, addrOnce);
+ ExprClearProperty(pExpr, EP_Subrtn);
+ addrOnce = 0;
+ }
+
+ /* Evaluate the expression and insert it into the temp table */
+ sqlite3ExprCode(pParse, pE2, r1);
+ sqlite3VdbeAddOp4(v, OP_MakeRecord, r1, 1, r2, &affinity, 1);
+ sqlite3VdbeAddOp4Int(v, OP_IdxInsert, iTab, r2, r1, 1);
+ }
+ sqlite3ReleaseTempReg(pParse, r1);
+ sqlite3ReleaseTempReg(pParse, r2);
+ }
+ if( pKeyInfo ){
+ sqlite3VdbeChangeP4(v, addr, (void *)pKeyInfo, P4_KEYINFO);
+ }
+ if( addrOnce ){
+ sqlite3VdbeAddOp1(v, OP_NullRow, iTab);
+ sqlite3VdbeJumpHere(v, addrOnce);
+ /* Subroutine return */
+ assert( ExprUseYSub(pExpr) );
+ assert( sqlite3VdbeGetOp(v,pExpr->y.sub.iAddr-1)->opcode==OP_BeginSubrtn
+ || pParse->nErr );
+ sqlite3VdbeAddOp3(v, OP_Return, pExpr->y.sub.regReturn,
+ pExpr->y.sub.iAddr, 1);
+ VdbeCoverage(v);
+ sqlite3ClearTempRegCache(pParse);
+ }
+}
+#endif /* SQLITE_OMIT_SUBQUERY */
+
+/*
+** 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.
+**
+** 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 if an error occurs.
+*/
+#ifndef SQLITE_OMIT_SUBQUERY
+int sqlite3CodeSubselect(Parse *pParse, Expr *pExpr){
+ int addrOnce = 0; /* Address of OP_Once at top of subroutine */
+ 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 */
+#ifdef SQLITE_ENABLE_STMT_SCANSTATUS
+ int addrExplain; /* Address of OP_Explain instruction */
+#endif
+
+ Vdbe *v = pParse->pVdbe;
+ assert( v!=0 );
+ if( pParse->nErr ) return 0;
+ testcase( pExpr->op==TK_EXISTS );
+ testcase( pExpr->op==TK_SELECT );
+ assert( pExpr->op==TK_EXISTS || pExpr->op==TK_SELECT );
+ assert( ExprUseXSelect(pExpr) );
+ pSel = pExpr->x.pSelect;
+
+ /* If this routine has already been coded, then invoke it as a
+ ** subroutine. */
+ if( ExprHasProperty(pExpr, EP_Subrtn) ){
+ ExplainQueryPlan((pParse, 0, "REUSE SUBQUERY %d", pSel->selId));
+ assert( ExprUseYSub(pExpr) );
+ sqlite3VdbeAddOp2(v, OP_Gosub, pExpr->y.sub.regReturn,
+ pExpr->y.sub.iAddr);
+ return pExpr->iTable;
+ }
+
+ /* Begin coding the subroutine */
+ assert( !ExprUseYWin(pExpr) );
+ assert( !ExprHasProperty(pExpr, EP_Reduced|EP_TokenOnly) );
+ ExprSetProperty(pExpr, EP_Subrtn);
+ pExpr->y.sub.regReturn = ++pParse->nMem;
+ pExpr->y.sub.iAddr =
+ sqlite3VdbeAddOp2(v, OP_BeginSubrtn, 0, pExpr->y.sub.regReturn) + 1;
+
+ /* 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) ){
+ addrOnce = 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.
+ */
+ ExplainQueryPlan2(addrExplain, (pParse, 1, "%sSCALAR SUBQUERY %d",
+ addrOnce?"":"CORRELATED ", pSel->selId));
+ sqlite3VdbeScanStatusCounters(v, addrExplain, addrExplain, -1);
+ 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( pSel->pLimit ){
+ /* The subquery already has a limit. If the pre-existing limit is X
+ ** then make the new limit X<>0 so that the new limit is either 1 or 0 */
+ sqlite3 *db = pParse->db;
+ pLimit = sqlite3Expr(db, TK_INTEGER, "0");
+ if( pLimit ){
+ pLimit->affExpr = SQLITE_AFF_NUMERIC;
+ pLimit = sqlite3PExpr(pParse, TK_NE,
+ sqlite3ExprDup(db, pSel->pLimit->pLeft, 0), pLimit);
+ }
+ sqlite3ExprDeferredDelete(pParse, pSel->pLimit->pLeft);
+ pSel->pLimit->pLeft = pLimit;
+ }else{
+ /* If there is no pre-existing limit add a limit of 1 */
+ pLimit = sqlite3Expr(pParse->db, TK_INTEGER, "1");
+ pSel->pLimit = sqlite3PExpr(pParse, TK_LIMIT, pLimit, 0);
+ }
+ pSel->iLimit = 0;
+ if( sqlite3Select(pParse, pSel, &dest) ){
+ pExpr->op2 = pExpr->op;
+ pExpr->op = TK_ERROR;
+ return 0;
+ }
+ pExpr->iTable = rReg = dest.iSDParm;
+ ExprSetVVAProperty(pExpr, EP_NoReduce);
+ if( addrOnce ){
+ sqlite3VdbeJumpHere(v, addrOnce);
+ }
+ sqlite3VdbeScanStatusRange(v, addrExplain, addrExplain, -1);
+
+ /* Subroutine return */
+ assert( ExprUseYSub(pExpr) );
+ assert( sqlite3VdbeGetOp(v,pExpr->y.sub.iAddr-1)->opcode==OP_BeginSubrtn
+ || pParse->nErr );
+ sqlite3VdbeAddOp3(v, OP_Return, pExpr->y.sub.regReturn,
+ pExpr->y.sub.iAddr, 1);
+ VdbeCoverage(v);
+ sqlite3ClearTempRegCache(pParse);
+ return rReg;
+}
+#endif /* SQLITE_OMIT_SUBQUERY */
+
+#ifndef SQLITE_OMIT_SUBQUERY
+/*
+** Expr pIn is an IN(...) expression. This function checks that the
+** sub-select on the RHS of the IN() operator has the same number of
+** columns as the vector on the LHS. Or, if the RHS of the IN() is not
+** a sub-query, that the LHS is a vector of size 1.
+*/
+int sqlite3ExprCheckIN(Parse *pParse, Expr *pIn){
+ int nVector = sqlite3ExprVectorSize(pIn->pLeft);
+ if( ExprUseXSelect(pIn) && !pParse->db->mallocFailed ){
+ if( nVector!=pIn->x.pSelect->pEList->nExpr ){
+ sqlite3SubselectError(pParse, pIn->x.pSelect->pEList->nExpr, nVector);
+ return 1;
+ }
+ }else if( nVector!=1 ){
+ sqlite3VectorErrorMsg(pParse, pIn->pLeft);
+ return 1;
+ }
+ return 0;
+}
+#endif
+
+#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 or vector expression. The
+** right-hand side (RHS) is an array of zero or more scalar values, or a
+** subquery. If the RHS is a subquery, the number of result columns must
+** match the number of columns in the vector on the LHS. If the RHS is
+** a list of values, the LHS must be a scalar.
+**
+** The IN operator is true if the LHS value is contained within the RHS.
+** The result is false if the LHS is definitely not in the RHS. The
+** result is NULL if the presence of the LHS in the RHS cannot be
+** determined due to NULLs.
+**
+** 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.
+**
+** See the separate in-operator.md documentation file in the canonical
+** SQLite source tree for additional information.
+*/
+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 */
+ int eType; /* Type of the RHS */
+ int rLhs; /* Register(s) holding the LHS values */
+ int rLhsOrig; /* LHS values prior to reordering by aiMap[] */
+ Vdbe *v; /* Statement under construction */
+ int *aiMap = 0; /* Map from vector field to index column */
+ char *zAff = 0; /* Affinity string for comparisons */
+ int nVector; /* Size of vectors for this IN operator */
+ int iDummy; /* Dummy parameter to exprCodeVector() */
+ Expr *pLeft; /* The LHS of the IN operator */
+ int i; /* loop counter */
+ int destStep2; /* Where to jump when NULLs seen in step 2 */
+ int destStep6 = 0; /* Start of code for Step 6 */
+ int addrTruthOp; /* Address of opcode that determines the IN is true */
+ int destNotNull; /* Jump here if a comparison is not true in step 6 */
+ int addrTop; /* Top of the step-6 loop */
+ int iTab = 0; /* Index to use */
+ u8 okConstFactor = pParse->okConstFactor;
+
+ assert( !ExprHasVVAProperty(pExpr,EP_Immutable) );
+ pLeft = pExpr->pLeft;
+ if( sqlite3ExprCheckIN(pParse, pExpr) ) return;
+ zAff = exprINAffinity(pParse, pExpr);
+ nVector = sqlite3ExprVectorSize(pExpr->pLeft);
+ aiMap = (int*)sqlite3DbMallocZero(
+ pParse->db, nVector*(sizeof(int) + sizeof(char)) + 1
+ );
+ if( pParse->db->mallocFailed ) goto sqlite3ExprCodeIN_oom_error;
+
+ /* Attempt to compute the RHS. After this step, if anything other than
+ ** IN_INDEX_NOOP is returned, the table opened with cursor iTab
+ ** contains the values that make up the RHS. If IN_INDEX_NOOP is returned,
+ ** the RHS has not yet been coded. */
+ 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,
+ aiMap, &iTab);
+
+ assert( pParse->nErr || nVector==1 || eType==IN_INDEX_EPH
+ || eType==IN_INDEX_INDEX_ASC || eType==IN_INDEX_INDEX_DESC
+ );
+#ifdef SQLITE_DEBUG
+ /* Confirm that aiMap[] contains nVector integer values between 0 and
+ ** nVector-1. */
+ for(i=0; i<nVector; i++){
+ int j, cnt;
+ for(cnt=j=0; j<nVector; j++) if( aiMap[j]==i ) cnt++;
+ assert( cnt==1 );
+ }
+#endif
+
+ /* Code the LHS, the <expr> from "<expr> IN (...)". If the LHS is a
+ ** vector, then it is stored in an array of nVector registers starting
+ ** at r1.
+ **
+ ** sqlite3FindInIndex() might have reordered the fields of the LHS vector
+ ** so that the fields are in the same order as an existing index. The
+ ** aiMap[] array contains a mapping from the original LHS field order to
+ ** the field order that matches the RHS index.
+ **
+ ** Avoid factoring the LHS of the IN(...) expression out of the loop,
+ ** even if it is constant, as OP_Affinity may be used on the register
+ ** by code generated below. */
+ assert( pParse->okConstFactor==okConstFactor );
+ pParse->okConstFactor = 0;
+ rLhsOrig = exprCodeVector(pParse, pLeft, &iDummy);
+ pParse->okConstFactor = okConstFactor;
+ for(i=0; i<nVector && aiMap[i]==i; i++){} /* Are LHS fields reordered? */
+ if( i==nVector ){
+ /* LHS fields are not reordered */
+ rLhs = rLhsOrig;
+ }else{
+ /* Need to reorder the LHS fields according to aiMap */
+ rLhs = sqlite3GetTempRange(pParse, nVector);
+ for(i=0; i<nVector; i++){
+ sqlite3VdbeAddOp3(v, OP_Copy, rLhsOrig+i, rLhs+aiMap[i], 0);
+ }
+ }
+
+ /* If sqlite3FindInIndex() did not find or create an index that is
+ ** suitable for evaluating the IN operator, then evaluate using a
+ ** sequence of comparisons.
+ **
+ ** This is step (1) in the in-operator.md optimized algorithm.
+ */
+ if( eType==IN_INDEX_NOOP ){
+ ExprList *pList;
+ CollSeq *pColl;
+ int labelOk = sqlite3VdbeMakeLabel(pParse);
+ int r2, regToFree;
+ int regCkNull = 0;
+ int ii;
+ assert( ExprUseXList(pExpr) );
+ pList = pExpr->x.pList;
+ pColl = sqlite3ExprCollSeq(pParse, pExpr->pLeft);
+ if( destIfNull!=destIfFalse ){
+ regCkNull = sqlite3GetTempReg(pParse);
+ sqlite3VdbeAddOp3(v, OP_BitAnd, rLhs, rLhs, regCkNull);
+ }
+ for(ii=0; ii<pList->nExpr; ii++){
+ r2 = sqlite3ExprCodeTemp(pParse, pList->a[ii].pExpr, &regToFree);
+ if( regCkNull && sqlite3ExprCanBeNull(pList->a[ii].pExpr) ){
+ sqlite3VdbeAddOp3(v, OP_BitAnd, regCkNull, r2, regCkNull);
+ }
+ sqlite3ReleaseTempReg(pParse, regToFree);
+ if( ii<pList->nExpr-1 || destIfNull!=destIfFalse ){
+ int op = rLhs!=r2 ? OP_Eq : OP_NotNull;
+ sqlite3VdbeAddOp4(v, op, rLhs, labelOk, r2,
+ (void*)pColl, P4_COLLSEQ);
+ VdbeCoverageIf(v, ii<pList->nExpr-1 && op==OP_Eq);
+ VdbeCoverageIf(v, ii==pList->nExpr-1 && op==OP_Eq);
+ VdbeCoverageIf(v, ii<pList->nExpr-1 && op==OP_NotNull);
+ VdbeCoverageIf(v, ii==pList->nExpr-1 && op==OP_NotNull);
+ sqlite3VdbeChangeP5(v, zAff[0]);
+ }else{
+ int op = rLhs!=r2 ? OP_Ne : OP_IsNull;
+ assert( destIfNull==destIfFalse );
+ sqlite3VdbeAddOp4(v, op, rLhs, destIfFalse, r2,
+ (void*)pColl, P4_COLLSEQ);
+ VdbeCoverageIf(v, op==OP_Ne);
+ VdbeCoverageIf(v, op==OP_IsNull);
+ sqlite3VdbeChangeP5(v, zAff[0] | SQLITE_JUMPIFNULL);
+ }
+ }
+ if( regCkNull ){
+ sqlite3VdbeAddOp2(v, OP_IsNull, regCkNull, destIfNull); VdbeCoverage(v);
+ sqlite3VdbeGoto(v, destIfFalse);
+ }
+ sqlite3VdbeResolveLabel(v, labelOk);
+ sqlite3ReleaseTempReg(pParse, regCkNull);
+ goto sqlite3ExprCodeIN_finished;
+ }
+
+ /* Step 2: Check to see if the LHS contains any NULL columns. If the
+ ** LHS does contain NULLs then the result must be either FALSE or NULL.
+ ** We will then skip the binary search of the RHS.
+ */
+ if( destIfNull==destIfFalse ){
+ destStep2 = destIfFalse;
+ }else{
+ destStep2 = destStep6 = sqlite3VdbeMakeLabel(pParse);
+ }
+ for(i=0; i<nVector; i++){
+ Expr *p = sqlite3VectorFieldSubexpr(pExpr->pLeft, i);
+ if( pParse->nErr ) goto sqlite3ExprCodeIN_oom_error;
+ if( sqlite3ExprCanBeNull(p) ){
+ sqlite3VdbeAddOp2(v, OP_IsNull, rLhs+i, destStep2);
+ VdbeCoverage(v);
+ }
+ }
+
+ /* Step 3. The LHS is now known to be non-NULL. Do the binary search
+ ** of the RHS using the LHS as a probe. If found, the result is
+ ** true.
+ */
+ if( eType==IN_INDEX_ROWID ){
+ /* In this case, the RHS is the ROWID of table b-tree and so we also
+ ** know that the RHS is non-NULL. Hence, we combine steps 3 and 4
+ ** into a single opcode. */
+ sqlite3VdbeAddOp3(v, OP_SeekRowid, iTab, destIfFalse, rLhs);
+ VdbeCoverage(v);
+ addrTruthOp = sqlite3VdbeAddOp0(v, OP_Goto); /* Return True */
+ }else{
+ sqlite3VdbeAddOp4(v, OP_Affinity, rLhs, nVector, 0, zAff, nVector);
+ if( destIfFalse==destIfNull ){
+ /* Combine Step 3 and Step 5 into a single opcode */
+ sqlite3VdbeAddOp4Int(v, OP_NotFound, iTab, destIfFalse,
+ rLhs, nVector); VdbeCoverage(v);
+ goto sqlite3ExprCodeIN_finished;
+ }
+ /* Ordinary Step 3, for the case where FALSE and NULL are distinct */
+ addrTruthOp = sqlite3VdbeAddOp4Int(v, OP_Found, iTab, 0,
+ rLhs, nVector); VdbeCoverage(v);
+ }
+
+ /* Step 4. If the RHS is known to be non-NULL and we did not find
+ ** an match on the search above, then the result must be FALSE.
+ */
+ if( rRhsHasNull && nVector==1 ){
+ sqlite3VdbeAddOp2(v, OP_NotNull, rRhsHasNull, destIfFalse);
+ VdbeCoverage(v);
+ }
+
+ /* Step 5. If we do not care about the difference between NULL and
+ ** FALSE, then just return false.
+ */
+ if( destIfFalse==destIfNull ) sqlite3VdbeGoto(v, destIfFalse);
+
+ /* Step 6: Loop through rows of the RHS. Compare each row to the LHS.
+ ** If any comparison is NULL, then the result is NULL. If all
+ ** comparisons are FALSE then the final result is FALSE.
+ **
+ ** For a scalar LHS, it is sufficient to check just the first row
+ ** of the RHS.
+ */
+ if( destStep6 ) sqlite3VdbeResolveLabel(v, destStep6);
+ addrTop = sqlite3VdbeAddOp2(v, OP_Rewind, iTab, destIfFalse);
+ VdbeCoverage(v);
+ if( nVector>1 ){
+ destNotNull = sqlite3VdbeMakeLabel(pParse);
+ }else{
+ /* For nVector==1, combine steps 6 and 7 by immediately returning
+ ** FALSE if the first comparison is not NULL */
+ destNotNull = destIfFalse;
+ }
+ for(i=0; i<nVector; i++){
+ Expr *p;
+ CollSeq *pColl;
+ int r3 = sqlite3GetTempReg(pParse);
+ p = sqlite3VectorFieldSubexpr(pLeft, i);
+ pColl = sqlite3ExprCollSeq(pParse, p);
+ sqlite3VdbeAddOp3(v, OP_Column, iTab, i, r3);
+ sqlite3VdbeAddOp4(v, OP_Ne, rLhs+i, destNotNull, r3,
+ (void*)pColl, P4_COLLSEQ);
+ VdbeCoverage(v);
+ sqlite3ReleaseTempReg(pParse, r3);
+ }
+ sqlite3VdbeAddOp2(v, OP_Goto, 0, destIfNull);
+ if( nVector>1 ){
+ sqlite3VdbeResolveLabel(v, destNotNull);
+ sqlite3VdbeAddOp2(v, OP_Next, iTab, addrTop+1);
+ VdbeCoverage(v);
+
+ /* Step 7: If we reach this point, we know that the result must
+ ** be false. */
+ sqlite3VdbeAddOp2(v, OP_Goto, 0, destIfFalse);
+ }
+
+ /* Jumps here in order to return true. */
+ sqlite3VdbeJumpHere(v, addrTruthOp);
+
+sqlite3ExprCodeIN_finished:
+ if( rLhs!=rLhsOrig ) sqlite3ReleaseTempReg(pParse, rLhs);
+ VdbeComment((v, "end IN expr"));
+sqlite3ExprCodeIN_oom_error:
+ sqlite3DbFree(pParse->db, aiMap);
+ sqlite3DbFree(pParse->db, zAff);
+}
+#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==3 && !negFlag) || (c==2) || (negFlag && value==SMALLEST_INT64)){
+#ifdef SQLITE_OMIT_FLOATING_POINT
+ sqlite3ErrorMsg(pParse, "oversized integer: %s%#T", negFlag?"-":"",pExpr);
+#else
+#ifndef SQLITE_OMIT_HEX_INTEGER
+ if( sqlite3_strnicmp(z,"0x",2)==0 ){
+ sqlite3ErrorMsg(pParse, "hex literal too big: %s%#T",
+ negFlag?"-":"",pExpr);
+ }else
+#endif
+ {
+ codeReal(v, z, negFlag, iMem);
+ }
+#endif
+ }else{
+ if( negFlag ){ value = c==3 ? SMALLEST_INT64 : -value; }
+ sqlite3VdbeAddOp4Dup8(v, OP_Int64, 0, iMem, 0, (u8*)&value, P4_INT64);
+ }
+ }
+}
+
+
+/* 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 + 1;
+ sqlite3ExprCodeCopy(pParse, pIdx->aColExpr->a[iIdxCol].pExpr, regOut);
+ pParse->iSelfTab = 0;
+ }else{
+ sqlite3ExprCodeGetColumnOfTable(pParse->pVdbe, pIdx->pTable, iTabCur,
+ iTabCol, regOut);
+ }
+}
+
+#ifndef SQLITE_OMIT_GENERATED_COLUMNS
+/*
+** Generate code that will compute the value of generated column pCol
+** and store the result in register regOut
+*/
+void sqlite3ExprCodeGeneratedColumn(
+ Parse *pParse, /* Parsing context */
+ Table *pTab, /* Table containing the generated column */
+ Column *pCol, /* The generated column */
+ int regOut /* Put the result in this register */
+){
+ int iAddr;
+ Vdbe *v = pParse->pVdbe;
+ int nErr = pParse->nErr;
+ assert( v!=0 );
+ assert( pParse->iSelfTab!=0 );
+ if( pParse->iSelfTab>0 ){
+ iAddr = sqlite3VdbeAddOp3(v, OP_IfNullRow, pParse->iSelfTab-1, 0, regOut);
+ }else{
+ iAddr = 0;
+ }
+ sqlite3ExprCodeCopy(pParse, sqlite3ColumnExpr(pTab,pCol), regOut);
+ if( pCol->affinity>=SQLITE_AFF_TEXT ){
+ sqlite3VdbeAddOp4(v, OP_Affinity, regOut, 1, 0, &pCol->affinity, 1);
+ }
+ if( iAddr ) sqlite3VdbeJumpHere(v, iAddr);
+ if( pParse->nErr>nErr ) pParse->db->errByteOffset = -1;
+}
+#endif /* SQLITE_OMIT_GENERATED_COLUMNS */
+
+/*
+** Generate code to extract the value of the iCol-th column of a table.
+*/
+void sqlite3ExprCodeGetColumnOfTable(
+ Vdbe *v, /* Parsing context */
+ 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 */
+){
+ Column *pCol;
+ assert( v!=0 );
+ assert( pTab!=0 );
+ assert( iCol!=XN_EXPR );
+ if( iCol<0 || iCol==pTab->iPKey ){
+ sqlite3VdbeAddOp2(v, OP_Rowid, iTabCur, regOut);
+ VdbeComment((v, "%s.rowid", pTab->zName));
+ }else{
+ int op;
+ int x;
+ if( IsVirtual(pTab) ){
+ op = OP_VColumn;
+ x = iCol;
+#ifndef SQLITE_OMIT_GENERATED_COLUMNS
+ }else if( (pCol = &pTab->aCol[iCol])->colFlags & COLFLAG_VIRTUAL ){
+ Parse *pParse = sqlite3VdbeParser(v);
+ if( pCol->colFlags & COLFLAG_BUSY ){
+ sqlite3ErrorMsg(pParse, "generated column loop on \"%s\"",
+ pCol->zCnName);
+ }else{
+ int savedSelfTab = pParse->iSelfTab;
+ pCol->colFlags |= COLFLAG_BUSY;
+ pParse->iSelfTab = iTabCur+1;
+ sqlite3ExprCodeGeneratedColumn(pParse, pTab, pCol, regOut);
+ pParse->iSelfTab = savedSelfTab;
+ pCol->colFlags &= ~COLFLAG_BUSY;
+ }
+ return;
+#endif
+ }else if( !HasRowid(pTab) ){
+ testcase( iCol!=sqlite3TableColumnToStorage(pTab, iCol) );
+ x = sqlite3TableColumnToIndex(sqlite3PrimaryKeyIndex(pTab), iCol);
+ op = OP_Column;
+ }else{
+ x = sqlite3TableColumnToStorage(pTab,iCol);
+ testcase( x!=iCol );
+ op = OP_Column;
+ }
+ sqlite3VdbeAddOp3(v, op, iTabCur, x, regOut);
+ sqlite3ColumnDefault(v, pTab, iCol, regOut);
+ }
+}
+
+/*
+** Generate code that will extract the iColumn-th column from
+** table pTab and store the column value in register iReg.
+**
+** 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 */
+){
+ assert( pParse->pVdbe!=0 );
+ assert( (p5 & (OPFLAG_NOCHNG|OPFLAG_TYPEOFARG|OPFLAG_LENGTHARG))==p5 );
+ assert( IsVirtual(pTab) || (p5 & OPFLAG_NOCHNG)==0 );
+ sqlite3ExprCodeGetColumnOfTable(pParse->pVdbe, pTab, iTable, iColumn, iReg);
+ if( p5 ){
+ VdbeOp *pOp = sqlite3VdbeGetLastOp(pParse->pVdbe);
+ if( pOp->opcode==OP_Column ) pOp->p5 = p5;
+ if( pOp->opcode==OP_VColumn ) pOp->p5 = (p5 & OPFLAG_NOCHNG);
+ }
+ return iReg;
+}
+
+/*
+** Generate code to move content from registers iFrom...iFrom+nReg-1
+** over to iTo..iTo+nReg-1.
+*/
+void sqlite3ExprCodeMove(Parse *pParse, int iFrom, int iTo, int nReg){
+ sqlite3VdbeAddOp3(pParse->pVdbe, OP_Move, iFrom, iTo, nReg);
+}
+
+/*
+** Convert a scalar expression node to a TK_REGISTER referencing
+** register iReg. The caller must ensure that iReg already contains
+** the correct value for the expression.
+*/
+static void exprToRegister(Expr *pExpr, int iReg){
+ Expr *p = sqlite3ExprSkipCollateAndLikely(pExpr);
+ if( NEVER(p==0) ) return;
+ p->op2 = p->op;
+ p->op = TK_REGISTER;
+ p->iTable = iReg;
+ ExprClearProperty(p, EP_Skip);
+}
+
+/*
+** Evaluate an expression (either a vector or a scalar expression) and store
+** the result in contiguous temporary registers. Return the index of
+** the first register used to store the result.
+**
+** If the returned result register is a temporary scalar, then also write
+** that register number into *piFreeable. If the returned result register
+** is not a temporary or if the expression is a vector set *piFreeable
+** to 0.
+*/
+static int exprCodeVector(Parse *pParse, Expr *p, int *piFreeable){
+ int iResult;
+ int nResult = sqlite3ExprVectorSize(p);
+ if( nResult==1 ){
+ iResult = sqlite3ExprCodeTemp(pParse, p, piFreeable);
+ }else{
+ *piFreeable = 0;
+ if( p->op==TK_SELECT ){
+#if SQLITE_OMIT_SUBQUERY
+ iResult = 0;
+#else
+ iResult = sqlite3CodeSubselect(pParse, p);
+#endif
+ }else{
+ int i;
+ iResult = pParse->nMem+1;
+ pParse->nMem += nResult;
+ assert( ExprUseXList(p) );
+ for(i=0; i<nResult; i++){
+ sqlite3ExprCodeFactorable(pParse, p->x.pList->a[i].pExpr, i+iResult);
+ }
+ }
+ }
+ return iResult;
+}
+
+/*
+** If the last opcode is a OP_Copy, then set the do-not-merge flag (p5)
+** so that a subsequent copy will not be merged into this one.
+*/
+static void setDoNotMergeFlagOnCopy(Vdbe *v){
+ if( sqlite3VdbeGetLastOp(v)->opcode==OP_Copy ){
+ sqlite3VdbeChangeP5(v, 1); /* Tag trailing OP_Copy as not mergeable */
+ }
+}
+
+/*
+** Generate code to implement special SQL functions that are implemented
+** in-line rather than by using the usual callbacks.
+*/
+static int exprCodeInlineFunction(
+ Parse *pParse, /* Parsing context */
+ ExprList *pFarg, /* List of function arguments */
+ int iFuncId, /* Function ID. One of the INTFUNC_... values */
+ int target /* Store function result in this register */
+){
+ int nFarg;
+ Vdbe *v = pParse->pVdbe;
+ assert( v!=0 );
+ assert( pFarg!=0 );
+ nFarg = pFarg->nExpr;
+ assert( nFarg>0 ); /* All in-line functions have at least one argument */
+ switch( iFuncId ){
+ case INLINEFUNC_coalesce: {
+ /* Attempt a direct implementation of the built-in COALESCE() and
+ ** IFNULL() functions. This avoids unnecessary evaluation of
+ ** arguments past the first non-NULL argument.
+ */
+ int endCoalesce = sqlite3VdbeMakeLabel(pParse);
+ int i;
+ assert( nFarg>=2 );
+ sqlite3ExprCode(pParse, pFarg->a[0].pExpr, target);
+ for(i=1; i<nFarg; i++){
+ sqlite3VdbeAddOp2(v, OP_NotNull, target, endCoalesce);
+ VdbeCoverage(v);
+ sqlite3ExprCode(pParse, pFarg->a[i].pExpr, target);
+ }
+ setDoNotMergeFlagOnCopy(v);
+ sqlite3VdbeResolveLabel(v, endCoalesce);
+ break;
+ }
+ case INLINEFUNC_iif: {
+ Expr caseExpr;
+ memset(&caseExpr, 0, sizeof(caseExpr));
+ caseExpr.op = TK_CASE;
+ caseExpr.x.pList = pFarg;
+ return sqlite3ExprCodeTarget(pParse, &caseExpr, target);
+ }
+#ifdef SQLITE_ENABLE_OFFSET_SQL_FUNC
+ case INLINEFUNC_sqlite_offset: {
+ Expr *pArg = pFarg->a[0].pExpr;
+ if( pArg->op==TK_COLUMN && pArg->iTable>=0 ){
+ sqlite3VdbeAddOp3(v, OP_Offset, pArg->iTable, pArg->iColumn, target);
+ }else{
+ sqlite3VdbeAddOp2(v, OP_Null, 0, target);
+ }
+ break;
+ }
+#endif
+ default: {
+ /* The UNLIKELY() function is a no-op. The result is the value
+ ** of the first argument.
+ */
+ assert( nFarg==1 || nFarg==2 );
+ target = sqlite3ExprCodeTarget(pParse, pFarg->a[0].pExpr, target);
+ break;
+ }
+
+ /***********************************************************************
+ ** Test-only SQL functions that are only usable if enabled
+ ** via SQLITE_TESTCTRL_INTERNAL_FUNCTIONS
+ */
+#if !defined(SQLITE_UNTESTABLE)
+ case INLINEFUNC_expr_compare: {
+ /* Compare two expressions using sqlite3ExprCompare() */
+ assert( nFarg==2 );
+ sqlite3VdbeAddOp2(v, OP_Integer,
+ sqlite3ExprCompare(0,pFarg->a[0].pExpr, pFarg->a[1].pExpr,-1),
+ target);
+ break;
+ }
+
+ case INLINEFUNC_expr_implies_expr: {
+ /* Compare two expressions using sqlite3ExprImpliesExpr() */
+ assert( nFarg==2 );
+ sqlite3VdbeAddOp2(v, OP_Integer,
+ sqlite3ExprImpliesExpr(pParse,pFarg->a[0].pExpr, pFarg->a[1].pExpr,-1),
+ target);
+ break;
+ }
+
+ case INLINEFUNC_implies_nonnull_row: {
+ /* Result of sqlite3ExprImpliesNonNullRow() */
+ Expr *pA1;
+ assert( nFarg==2 );
+ pA1 = pFarg->a[1].pExpr;
+ if( pA1->op==TK_COLUMN ){
+ sqlite3VdbeAddOp2(v, OP_Integer,
+ sqlite3ExprImpliesNonNullRow(pFarg->a[0].pExpr,pA1->iTable,1),
+ target);
+ }else{
+ sqlite3VdbeAddOp2(v, OP_Null, 0, target);
+ }
+ break;
+ }
+
+ case INLINEFUNC_affinity: {
+ /* The AFFINITY() function evaluates to a string that describes
+ ** the type affinity of the argument. This is used for testing of
+ ** the SQLite type logic.
+ */
+ const char *azAff[] = { "blob", "text", "numeric", "integer",
+ "real", "flexnum" };
+ char aff;
+ assert( nFarg==1 );
+ aff = sqlite3ExprAffinity(pFarg->a[0].pExpr);
+ assert( aff<=SQLITE_AFF_NONE
+ || (aff>=SQLITE_AFF_BLOB && aff<=SQLITE_AFF_FLEXNUM) );
+ sqlite3VdbeLoadString(v, target,
+ (aff<=SQLITE_AFF_NONE) ? "none" : azAff[aff-SQLITE_AFF_BLOB]);
+ break;
+ }
+#endif /* !defined(SQLITE_UNTESTABLE) */
+ }
+ return target;
+}
+
+/*
+** Check to see if pExpr is one of the indexed expressions on pParse->pIdxEpr.
+** If it is, then resolve the expression by reading from the index and
+** return the register into which the value has been read. If pExpr is
+** not an indexed expression, then return negative.
+*/
+static SQLITE_NOINLINE int sqlite3IndexedExprLookup(
+ Parse *pParse, /* The parsing context */
+ Expr *pExpr, /* The expression to potentially bypass */
+ int target /* Where to store the result of the expression */
+){
+ IndexedExpr *p;
+ Vdbe *v;
+ for(p=pParse->pIdxEpr; p; p=p->pIENext){
+ u8 exprAff;
+ int iDataCur = p->iDataCur;
+ if( iDataCur<0 ) continue;
+ if( pParse->iSelfTab ){
+ if( p->iDataCur!=pParse->iSelfTab-1 ) continue;
+ iDataCur = -1;
+ }
+ if( sqlite3ExprCompare(0, pExpr, p->pExpr, iDataCur)!=0 ) continue;
+ assert( p->aff>=SQLITE_AFF_BLOB && p->aff<=SQLITE_AFF_NUMERIC );
+ exprAff = sqlite3ExprAffinity(pExpr);
+ if( (exprAff<=SQLITE_AFF_BLOB && p->aff!=SQLITE_AFF_BLOB)
+ || (exprAff==SQLITE_AFF_TEXT && p->aff!=SQLITE_AFF_TEXT)
+ || (exprAff>=SQLITE_AFF_NUMERIC && p->aff!=SQLITE_AFF_NUMERIC)
+ ){
+ /* Affinity mismatch on a generated column */
+ continue;
+ }
+
+ v = pParse->pVdbe;
+ assert( v!=0 );
+ if( p->bMaybeNullRow ){
+ /* If the index is on a NULL row due to an outer join, then we
+ ** cannot extract the value from the index. The value must be
+ ** computed using the original expression. */
+ int addr = sqlite3VdbeCurrentAddr(v);
+ sqlite3VdbeAddOp3(v, OP_IfNullRow, p->iIdxCur, addr+3, target);
+ VdbeCoverage(v);
+ sqlite3VdbeAddOp3(v, OP_Column, p->iIdxCur, p->iIdxCol, target);
+ VdbeComment((v, "%s expr-column %d", p->zIdxName, p->iIdxCol));
+ sqlite3VdbeGoto(v, 0);
+ p = pParse->pIdxEpr;
+ pParse->pIdxEpr = 0;
+ sqlite3ExprCode(pParse, pExpr, target);
+ pParse->pIdxEpr = p;
+ sqlite3VdbeJumpHere(v, addr+2);
+ }else{
+ sqlite3VdbeAddOp3(v, OP_Column, p->iIdxCur, p->iIdxCol, target);
+ VdbeComment((v, "%s expr-column %d", p->zIdxName, p->iIdxCol));
+ }
+ return target;
+ }
+ return -1; /* Not found */
+}
+
+
+/*
+** Expresion pExpr is guaranteed to be a TK_COLUMN or equivalent. This
+** function checks the Parse.pIdxPartExpr list to see if this column
+** can be replaced with a constant value. If so, it generates code to
+** put the constant value in a register (ideally, but not necessarily,
+** register iTarget) and returns the register number.
+**
+** Or, if the TK_COLUMN cannot be replaced by a constant, zero is
+** returned.
+*/
+static int exprPartidxExprLookup(Parse *pParse, Expr *pExpr, int iTarget){
+ IndexedExpr *p;
+ for(p=pParse->pIdxPartExpr; p; p=p->pIENext){
+ if( pExpr->iColumn==p->iIdxCol && pExpr->iTable==p->iDataCur ){
+ Vdbe *v = pParse->pVdbe;
+ int addr = 0;
+ int ret;
+
+ if( p->bMaybeNullRow ){
+ addr = sqlite3VdbeAddOp1(v, OP_IfNullRow, p->iIdxCur);
+ }
+ ret = sqlite3ExprCodeTarget(pParse, p->pExpr, iTarget);
+ sqlite3VdbeAddOp4(pParse->pVdbe, OP_Affinity, ret, 1, 0,
+ (const char*)&p->aff, 1);
+ if( addr ){
+ sqlite3VdbeJumpHere(v, addr);
+ sqlite3VdbeChangeP3(v, addr, ret);
+ }
+ return ret;
+ }
+ }
+ return 0;
+}
+
+
+/*
+** 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; /* Various register numbers */
+ Expr tempX; /* Temporary expression node */
+ int p5 = 0;
+
+ assert( target>0 && target<=pParse->nMem );
+ assert( v!=0 );
+
+expr_code_doover:
+ if( pExpr==0 ){
+ op = TK_NULL;
+ }else if( pParse->pIdxEpr!=0
+ && !ExprHasProperty(pExpr, EP_Leaf)
+ && (r1 = sqlite3IndexedExprLookup(pParse, pExpr, target))>=0
+ ){
+ return r1;
+ }else{
+ assert( !ExprHasVVAProperty(pExpr,EP_Immutable) );
+ op = pExpr->op;
+ }
+ assert( op!=TK_ORDER );
+ switch( op ){
+ case TK_AGG_COLUMN: {
+ AggInfo *pAggInfo = pExpr->pAggInfo;
+ struct AggInfo_col *pCol;
+ assert( pAggInfo!=0 );
+ assert( pExpr->iAgg>=0 );
+ if( pExpr->iAgg>=pAggInfo->nColumn ){
+ /* Happens when the left table of a RIGHT JOIN is null and
+ ** is using an expression index */
+ sqlite3VdbeAddOp2(v, OP_Null, 0, target);
+#ifdef SQLITE_VDBE_COVERAGE
+ /* Verify that the OP_Null above is exercised by tests
+ ** tag-20230325-2 */
+ sqlite3VdbeAddOp3(v, OP_NotNull, target, 1, 20230325);
+ VdbeCoverageNeverTaken(v);
+#endif
+ break;
+ }
+ pCol = &pAggInfo->aCol[pExpr->iAgg];
+ if( !pAggInfo->directMode ){
+ return AggInfoColumnReg(pAggInfo, pExpr->iAgg);
+ }else if( pAggInfo->useSortingIdx ){
+ Table *pTab = pCol->pTab;
+ sqlite3VdbeAddOp3(v, OP_Column, pAggInfo->sortingIdxPTab,
+ pCol->iSorterColumn, target);
+ if( pTab==0 ){
+ /* No comment added */
+ }else if( pCol->iColumn<0 ){
+ VdbeComment((v,"%s.rowid",pTab->zName));
+ }else{
+ VdbeComment((v,"%s.%s",
+ pTab->zName, pTab->aCol[pCol->iColumn].zCnName));
+ if( pTab->aCol[pCol->iColumn].affinity==SQLITE_AFF_REAL ){
+ sqlite3VdbeAddOp1(v, OP_RealAffinity, target);
+ }
+ }
+ return target;
+ }else if( pExpr->y.pTab==0 ){
+ /* This case happens when the argument to an aggregate function
+ ** is rewritten by aggregateConvertIndexedExprRefToColumn() */
+ sqlite3VdbeAddOp3(v, OP_Column, pExpr->iTable, pExpr->iColumn, target);
+ return target;
+ }
+ /* Otherwise, fall thru into the TK_COLUMN case */
+ /* no break */ deliberate_fall_through
+ }
+ case TK_COLUMN: {
+ int iTab = pExpr->iTable;
+ int iReg;
+ if( ExprHasProperty(pExpr, EP_FixedCol) ){
+ /* This COLUMN expression is really a constant due to WHERE clause
+ ** constraints, and that constant is coded by the pExpr->pLeft
+ ** expression. However, make sure the constant has the correct
+ ** datatype by applying the Affinity of the table column to the
+ ** constant.
+ */
+ int aff;
+ iReg = sqlite3ExprCodeTarget(pParse, pExpr->pLeft,target);
+ assert( ExprUseYTab(pExpr) );
+ assert( pExpr->y.pTab!=0 );
+ aff = sqlite3TableColumnAffinity(pExpr->y.pTab, pExpr->iColumn);
+ if( aff>SQLITE_AFF_BLOB ){
+ static const char zAff[] = "B\000C\000D\000E\000F";
+ assert( SQLITE_AFF_BLOB=='A' );
+ assert( SQLITE_AFF_TEXT=='B' );
+ sqlite3VdbeAddOp4(v, OP_Affinity, iReg, 1, 0,
+ &zAff[(aff-'B')*2], P4_STATIC);
+ }
+ return iReg;
+ }
+ if( iTab<0 ){
+ if( pParse->iSelfTab<0 ){
+ /* Other columns in the same row for CHECK constraints or
+ ** generated columns or for inserting into partial index.
+ ** The row is unpacked into registers beginning at
+ ** 0-(pParse->iSelfTab). The rowid (if any) is in a register
+ ** immediately prior to the first column.
+ */
+ Column *pCol;
+ Table *pTab;
+ int iSrc;
+ int iCol = pExpr->iColumn;
+ assert( ExprUseYTab(pExpr) );
+ pTab = pExpr->y.pTab;
+ assert( pTab!=0 );
+ assert( iCol>=XN_ROWID );
+ assert( iCol<pTab->nCol );
+ if( iCol<0 ){
+ return -1-pParse->iSelfTab;
+ }
+ pCol = pTab->aCol + iCol;
+ testcase( iCol!=sqlite3TableColumnToStorage(pTab,iCol) );
+ iSrc = sqlite3TableColumnToStorage(pTab, iCol) - pParse->iSelfTab;
+#ifndef SQLITE_OMIT_GENERATED_COLUMNS
+ if( pCol->colFlags & COLFLAG_GENERATED ){
+ if( pCol->colFlags & COLFLAG_BUSY ){
+ sqlite3ErrorMsg(pParse, "generated column loop on \"%s\"",
+ pCol->zCnName);
+ return 0;
+ }
+ pCol->colFlags |= COLFLAG_BUSY;
+ if( pCol->colFlags & COLFLAG_NOTAVAIL ){
+ sqlite3ExprCodeGeneratedColumn(pParse, pTab, pCol, iSrc);
+ }
+ pCol->colFlags &= ~(COLFLAG_BUSY|COLFLAG_NOTAVAIL);
+ return iSrc;
+ }else
+#endif /* SQLITE_OMIT_GENERATED_COLUMNS */
+ if( pCol->affinity==SQLITE_AFF_REAL ){
+ sqlite3VdbeAddOp2(v, OP_SCopy, iSrc, target);
+ sqlite3VdbeAddOp1(v, OP_RealAffinity, target);
+ return target;
+ }else{
+ return iSrc;
+ }
+ }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 - 1;
+ }
+ }
+ else if( pParse->pIdxPartExpr
+ && 0!=(r1 = exprPartidxExprLookup(pParse, pExpr, target))
+ ){
+ return r1;
+ }
+ assert( ExprUseYTab(pExpr) );
+ assert( pExpr->y.pTab!=0 );
+ iReg = sqlite3ExprCodeGetColumn(pParse, pExpr->y.pTab,
+ pExpr->iColumn, iTab, target,
+ pExpr->op2);
+ return iReg;
+ }
+ case TK_INTEGER: {
+ codeInteger(pParse, pExpr, 0, target);
+ return target;
+ }
+ case TK_TRUEFALSE: {
+ sqlite3VdbeAddOp2(v, OP_Integer, sqlite3ExprTruthValue(pExpr), target);
+ return target;
+ }
+#ifndef SQLITE_OMIT_FLOATING_POINT
+ case TK_FLOAT: {
+ assert( !ExprHasProperty(pExpr, EP_IntValue) );
+ codeReal(v, pExpr->u.zToken, 0, target);
+ return target;
+ }
+#endif
+ case TK_STRING: {
+ assert( !ExprHasProperty(pExpr, EP_IntValue) );
+ sqlite3VdbeLoadString(v, target, pExpr->u.zToken);
+ return target;
+ }
+ default: {
+ /* Make NULL the default case so that if a bug causes an illegal
+ ** Expr node to be passed into this function, it will be handled
+ ** sanely and not crash. But keep the assert() to bring the problem
+ ** to the attention of the developers. */
+ assert( op==TK_NULL || op==TK_ERROR || pParse->db->mallocFailed );
+ sqlite3VdbeAddOp2(v, OP_Null, 0, target);
+ return target;
+ }
+#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);
+ return target;
+ }
+#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 ){
+ const char *z = sqlite3VListNumToName(pParse->pVList, pExpr->iColumn);
+ assert( pExpr->u.zToken[0]=='?' || (z && !strcmp(pExpr->u.zToken, z)) );
+ pParse->pVList[0] = 0; /* Indicate VList may no longer be enlarged */
+ sqlite3VdbeAppendP4(v, (char*)z, P4_STATIC);
+ }
+ return target;
+ }
+ case TK_REGISTER: {
+ return pExpr->iTable;
+ }
+#ifndef SQLITE_OMIT_CAST
+ case TK_CAST: {
+ /* Expressions of the form: CAST(pLeft AS token) */
+ sqlite3ExprCode(pParse, pExpr->pLeft, target);
+ assert( inReg==target );
+ assert( !ExprHasProperty(pExpr, EP_IntValue) );
+ sqlite3VdbeAddOp2(v, OP_Cast, target,
+ sqlite3AffinityType(pExpr->u.zToken, 0));
+ return inReg;
+ }
+#endif /* SQLITE_OMIT_CAST */
+ case TK_IS:
+ case TK_ISNOT:
+ op = (op==TK_IS) ? TK_EQ : TK_NE;
+ p5 = SQLITE_NULLEQ;
+ /* fall-through */
+ case TK_LT:
+ case TK_LE:
+ case TK_GT:
+ case TK_GE:
+ case TK_NE:
+ case TK_EQ: {
+ Expr *pLeft = pExpr->pLeft;
+ if( sqlite3ExprIsVector(pLeft) ){
+ codeVectorCompare(pParse, pExpr, target, op, p5);
+ }else{
+ r1 = sqlite3ExprCodeTemp(pParse, pLeft, &regFree1);
+ r2 = sqlite3ExprCodeTemp(pParse, pExpr->pRight, &regFree2);
+ sqlite3VdbeAddOp2(v, OP_Integer, 1, inReg);
+ codeCompare(pParse, pLeft, pExpr->pRight, op, r1, r2,
+ sqlite3VdbeCurrentAddr(v)+2, p5,
+ ExprHasProperty(pExpr,EP_Commuted));
+ 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);
+ if( p5==SQLITE_NULLEQ ){
+ sqlite3VdbeAddOp2(v, OP_Integer, 0, inReg);
+ }else{
+ sqlite3VdbeAddOp3(v, OP_ZeroOrNull, r1, inReg, r2);
+ }
+ 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, &regFree1);
+ r2 = sqlite3ExprCodeTemp(pParse, pExpr->pRight, &regFree2);
+ 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);
+ return target;
+#ifndef SQLITE_OMIT_FLOATING_POINT
+ }else if( pLeft->op==TK_FLOAT ){
+ assert( !ExprHasProperty(pExpr, EP_IntValue) );
+ codeReal(v, pLeft->u.zToken, 1, target);
+ return target;
+#endif
+ }else{
+ tempX.op = TK_INTEGER;
+ tempX.flags = EP_IntValue|EP_TokenOnly;
+ tempX.u.iValue = 0;
+ ExprClearVVAProperties(&tempX);
+ r1 = sqlite3ExprCodeTemp(pParse, &tempX, &regFree1);
+ r2 = sqlite3ExprCodeTemp(pParse, pExpr->pLeft, &regFree2);
+ sqlite3VdbeAddOp3(v, OP_Subtract, r2, r1, target);
+ testcase( regFree2==0 );
+ }
+ 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, &regFree1);
+ testcase( regFree1==0 );
+ sqlite3VdbeAddOp2(v, op, r1, inReg);
+ break;
+ }
+ case TK_TRUTH: {
+ int isTrue; /* IS TRUE or IS NOT TRUE */
+ int bNormal; /* IS TRUE or IS FALSE */
+ r1 = sqlite3ExprCodeTemp(pParse, pExpr->pLeft, &regFree1);
+ testcase( regFree1==0 );
+ isTrue = sqlite3ExprTruthValue(pExpr->pRight);
+ bNormal = pExpr->op2==TK_IS;
+ testcase( isTrue && bNormal);
+ testcase( !isTrue && bNormal);
+ sqlite3VdbeAddOp4Int(v, OP_IsTrue, r1, inReg, !isTrue, isTrue ^ bNormal);
+ 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, &regFree1);
+ 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
+ || NEVER(pExpr->iAgg<0)
+ || NEVER(pExpr->iAgg>=pInfo->nFunc)
+ ){
+ assert( !ExprHasProperty(pExpr, EP_IntValue) );
+ sqlite3ErrorMsg(pParse, "misuse of aggregate: %#T()", pExpr);
+ }else{
+ return AggInfoFuncReg(pInfo, pExpr->iAgg);
+ }
+ break;
+ }
+ case TK_FUNCTION: {
+ ExprList *pFarg; /* List of function arguments */
+ int nFarg; /* Number of function arguments */
+ FuncDef *pDef; /* The function definition object */
+ const char *zId; /* The function name */
+ u32 constMask = 0; /* Mask of function arguments that are constant */
+ int i; /* Loop counter */
+ sqlite3 *db = pParse->db; /* The database connection */
+ u8 enc = ENC(db); /* The text encoding used by this database */
+ CollSeq *pColl = 0; /* A collating sequence */
+
+#ifndef SQLITE_OMIT_WINDOWFUNC
+ if( ExprHasProperty(pExpr, EP_WinFunc) ){
+ return pExpr->y.pWin->regResult;
+ }
+#endif
+
+ if( ConstFactorOk(pParse) && sqlite3ExprIsConstantNotJoin(pExpr) ){
+ /* SQL functions can be expensive. So try to avoid running them
+ ** multiple times if we know they always give the same result */
+ return sqlite3ExprCodeRunJustOnce(pParse, pExpr, -1);
+ }
+ assert( !ExprHasProperty(pExpr, EP_TokenOnly) );
+ assert( ExprUseXList(pExpr) );
+ pFarg = pExpr->x.pList;
+ nFarg = pFarg ? pFarg->nExpr : 0;
+ assert( !ExprHasProperty(pExpr, EP_IntValue) );
+ zId = pExpr->u.zToken;
+ pDef = sqlite3FindFunction(db, zId, nFarg, enc, 0);
+#ifdef SQLITE_ENABLE_UNKNOWN_SQL_FUNCTION
+ if( pDef==0 && pParse->explain ){
+ pDef = sqlite3FindFunction(db, "unknown", nFarg, enc, 0);
+ }
+#endif
+ if( pDef==0 || pDef->xFinalize!=0 ){
+ sqlite3ErrorMsg(pParse, "unknown function: %#T()", pExpr);
+ break;
+ }
+ if( (pDef->funcFlags & SQLITE_FUNC_INLINE)!=0 && ALWAYS(pFarg!=0) ){
+ assert( (pDef->funcFlags & SQLITE_FUNC_UNSAFE)==0 );
+ assert( (pDef->funcFlags & SQLITE_FUNC_DIRECT)==0 );
+ return exprCodeInlineFunction(pParse, pFarg,
+ SQLITE_PTR_TO_INT(pDef->pUserData), target);
+ }else if( pDef->funcFlags & (SQLITE_FUNC_DIRECT|SQLITE_FUNC_UNSAFE) ){
+ sqlite3ExprFunctionUsable(pParse, pExpr, pDef);
+ }
+
+ 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() and octet_length() functions,
+ ** set the P5 parameter to the OP_Column opcode to OPFLAG_LENGTHARG
+ ** or OPFLAG_TYPEOFARG or OPFLAG_BYTELENARG 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 );
+ assert( SQLITE_FUNC_BYTELEN==OPFLAG_BYTELENARG );
+ assert( (OPFLAG_LENGTHARG|OPFLAG_TYPEOFARG)==OPFLAG_BYTELENARG );
+ testcase( (pDef->funcFlags & OPFLAG_BYTELENARG)==OPFLAG_LENGTHARG );
+ testcase( (pDef->funcFlags & OPFLAG_BYTELENARG)==OPFLAG_TYPEOFARG );
+ testcase( (pDef->funcFlags & OPFLAG_BYTELENARG)==OPFLAG_BYTELENARG);
+ pFarg->a[0].pExpr->op2 = pDef->funcFlags & OPFLAG_BYTELENARG;
+ }
+ }
+
+ sqlite3ExprCodeExprList(pParse, pFarg, r1, 0, SQLITE_ECEL_FACTOR);
+ }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 && ExprHasProperty(pExpr, 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);
+ }
+ sqlite3VdbeAddFunctionCall(pParse, constMask, r1, target, nFarg,
+ pDef, pExpr->op2);
+ if( nFarg ){
+ if( constMask==0 ){
+ sqlite3ReleaseTempRange(pParse, r1, nFarg);
+ }else{
+ sqlite3VdbeReleaseRegisters(pParse, r1, nFarg, constMask, 1);
+ }
+ }
+ return target;
+ }
+#ifndef SQLITE_OMIT_SUBQUERY
+ case TK_EXISTS:
+ case TK_SELECT: {
+ int nCol;
+ testcase( op==TK_EXISTS );
+ testcase( op==TK_SELECT );
+ if( pParse->db->mallocFailed ){
+ return 0;
+ }else if( op==TK_SELECT
+ && ALWAYS( ExprUseXSelect(pExpr) )
+ && (nCol = pExpr->x.pSelect->pEList->nExpr)!=1
+ ){
+ sqlite3SubselectError(pParse, nCol, 1);
+ }else{
+ return sqlite3CodeSubselect(pParse, pExpr);
+ }
+ break;
+ }
+ case TK_SELECT_COLUMN: {
+ int n;
+ Expr *pLeft = pExpr->pLeft;
+ if( pLeft->iTable==0 || pParse->withinRJSubrtn > pLeft->op2 ){
+ pLeft->iTable = sqlite3CodeSubselect(pParse, pLeft);
+ pLeft->op2 = pParse->withinRJSubrtn;
+ }
+ assert( pLeft->op==TK_SELECT || pLeft->op==TK_ERROR );
+ n = sqlite3ExprVectorSize(pLeft);
+ if( pExpr->iTable!=n ){
+ sqlite3ErrorMsg(pParse, "%d columns assigned %d values",
+ pExpr->iTable, n);
+ }
+ return pLeft->iTable + pExpr->iColumn;
+ }
+ case TK_IN: {
+ int destIfFalse = sqlite3VdbeMakeLabel(pParse);
+ int destIfNull = sqlite3VdbeMakeLabel(pParse);
+ 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);
+ return target;
+ }
+#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: {
+ exprCodeBetween(pParse, pExpr, target, 0, 0);
+ return target;
+ }
+ case TK_COLLATE: {
+ if( !ExprHasProperty(pExpr, EP_Collate) ){
+ /* A TK_COLLATE Expr node without the EP_Collate tag is a so-called
+ ** "SOFT-COLLATE" that is added to constraints that are pushed down
+ ** from outer queries into sub-queries by the push-down optimization.
+ ** Clear subtypes as subtypes may not cross a subquery boundary.
+ */
+ assert( pExpr->pLeft );
+ sqlite3ExprCode(pParse, pExpr->pLeft, target);
+ sqlite3VdbeAddOp1(v, OP_ClrSubtype, target);
+ return target;
+ }else{
+ pExpr = pExpr->pLeft;
+ goto expr_code_doover; /* 2018-04-28: Prevent deep recursion. */
+ }
+ }
+ case TK_SPAN:
+ case TK_UPLUS: {
+ pExpr = pExpr->pLeft;
+ goto expr_code_doover; /* 2018-04-28: Prevent deep recursion. OSSFuzz. */
+ }
+
+ 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;
+ int iCol;
+ int p1;
+
+ assert( ExprUseYTab(pExpr) );
+ pTab = pExpr->y.pTab;
+ iCol = pExpr->iColumn;
+ p1 = pExpr->iTable * (pTab->nCol+1) + 1
+ + sqlite3TableColumnToStorage(pTab, iCol);
+
+ assert( pExpr->iTable==0 || pExpr->iTable==1 );
+ assert( iCol>=-1 && iCol<pTab->nCol );
+ assert( pTab->iPKey<0 || iCol!=pTab->iPKey );
+ assert( p1>=0 && p1<(pTab->nCol*2+2) );
+
+ sqlite3VdbeAddOp2(v, OP_Param, p1, target);
+ VdbeComment((v, "r[%d]=%s.%s", target,
+ (pExpr->iTable ? "new" : "old"),
+ (pExpr->iColumn<0 ? "rowid" : pExpr->y.pTab->aCol[iCol].zCnName)
+ ));
+
+#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( iCol>=0 && pTab->aCol[iCol].affinity==SQLITE_AFF_REAL ){
+ sqlite3VdbeAddOp1(v, OP_RealAffinity, target);
+ }
+#endif
+ break;
+ }
+
+ case TK_VECTOR: {
+ sqlite3ErrorMsg(pParse, "row value misused");
+ break;
+ }
+
+ /* TK_IF_NULL_ROW Expr nodes are inserted ahead of expressions
+ ** that derive from the right-hand table of a LEFT JOIN. The
+ ** Expr.iTable value is the table number for the right-hand table.
+ ** The expression is only evaluated if that table is not currently
+ ** on a LEFT JOIN NULL row.
+ */
+ case TK_IF_NULL_ROW: {
+ int addrINR;
+ u8 okConstFactor = pParse->okConstFactor;
+ AggInfo *pAggInfo = pExpr->pAggInfo;
+ if( pAggInfo ){
+ assert( pExpr->iAgg>=0 && pExpr->iAgg<pAggInfo->nColumn );
+ if( !pAggInfo->directMode ){
+ inReg = AggInfoColumnReg(pAggInfo, pExpr->iAgg);
+ break;
+ }
+ if( pExpr->pAggInfo->useSortingIdx ){
+ sqlite3VdbeAddOp3(v, OP_Column, pAggInfo->sortingIdxPTab,
+ pAggInfo->aCol[pExpr->iAgg].iSorterColumn,
+ target);
+ inReg = target;
+ break;
+ }
+ }
+ addrINR = sqlite3VdbeAddOp3(v, OP_IfNullRow, pExpr->iTable, 0, target);
+ /* The OP_IfNullRow opcode above can overwrite the result register with
+ ** NULL. So we have to ensure that the result register is not a value
+ ** that is suppose to be a constant. Two defenses are needed:
+ ** (1) Temporarily disable factoring of constant expressions
+ ** (2) Make sure the computed value really is stored in register
+ ** "target" and not someplace else.
+ */
+ pParse->okConstFactor = 0; /* note (1) above */
+ sqlite3ExprCode(pParse, pExpr->pLeft, target);
+ assert( target==inReg );
+ pParse->okConstFactor = okConstFactor;
+ sqlite3VdbeJumpHere(v, addrINR);
+ 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.
+ */
+ case 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) */
+ Expr *pDel = 0;
+ sqlite3 *db = pParse->db;
+
+ assert( ExprUseXList(pExpr) && pExpr->x.pList!=0 );
+ assert(pExpr->x.pList->nExpr > 0);
+ pEList = pExpr->x.pList;
+ aListelem = pEList->a;
+ nExpr = pEList->nExpr;
+ endLabel = sqlite3VdbeMakeLabel(pParse);
+ if( (pX = pExpr->pLeft)!=0 ){
+ pDel = sqlite3ExprDup(db, pX, 0);
+ if( db->mallocFailed ){
+ sqlite3ExprDelete(db, pDel);
+ break;
+ }
+ testcase( pX->op==TK_COLUMN );
+ exprToRegister(pDel, exprCodeVector(pParse, pDel, &regFree1));
+ testcase( regFree1==0 );
+ memset(&opCompare, 0, sizeof(opCompare));
+ opCompare.op = TK_EQ;
+ opCompare.pLeft = pDel;
+ 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){
+ if( pX ){
+ assert( pTest!=0 );
+ opCompare.pRight = aListelem[i].pExpr;
+ }else{
+ pTest = aListelem[i].pExpr;
+ }
+ nextCase = sqlite3VdbeMakeLabel(pParse);
+ 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);
+ sqlite3VdbeResolveLabel(v, nextCase);
+ }
+ if( (nExpr&1)!=0 ){
+ sqlite3ExprCode(pParse, pEList->a[nExpr-1].pExpr, target);
+ }else{
+ sqlite3VdbeAddOp2(v, OP_Null, 0, target);
+ }
+ sqlite3ExprDelete(db, pDel);
+ setDoNotMergeFlagOnCopy(v);
+ sqlite3VdbeResolveLabel(v, endLabel);
+ break;
+ }
+#ifndef SQLITE_OMIT_TRIGGER
+ case TK_RAISE: {
+ assert( pExpr->affExpr==OE_Rollback
+ || pExpr->affExpr==OE_Abort
+ || pExpr->affExpr==OE_Fail
+ || pExpr->affExpr==OE_Ignore
+ );
+ if( !pParse->pTriggerTab && !pParse->nested ){
+ sqlite3ErrorMsg(pParse,
+ "RAISE() may only be used within a trigger-program");
+ return 0;
+ }
+ if( pExpr->affExpr==OE_Abort ){
+ sqlite3MayAbort(pParse);
+ }
+ assert( !ExprHasProperty(pExpr, EP_IntValue) );
+ if( pExpr->affExpr==OE_Ignore ){
+ sqlite3VdbeAddOp4(
+ v, OP_Halt, SQLITE_OK, OE_Ignore, 0, pExpr->u.zToken,0);
+ VdbeCoverage(v);
+ }else{
+ sqlite3HaltConstraint(pParse,
+ pParse->pTriggerTab ? SQLITE_CONSTRAINT_TRIGGER : SQLITE_ERROR,
+ pExpr->affExpr, pExpr->u.zToken, 0, 0);
+ }
+
+ break;
+ }
+#endif
+ }
+ sqlite3ReleaseTempReg(pParse, regFree1);
+ sqlite3ReleaseTempReg(pParse, regFree2);
+ return inReg;
+}
+
+/*
+** Generate code that will evaluate expression pExpr just one time
+** per prepared statement execution.
+**
+** If the expression uses functions (that might throw an exception) then
+** guard them with an OP_Once opcode to ensure that the code is only executed
+** once. If no functions are involved, then factor the code out and put it at
+** the end of the prepared statement in the initialization section.
+**
+** If regDest>0 then the result is always stored in that register and the
+** result is not reusable. If regDest<0 then this routine is free to
+** store the value wherever it wants. The register where the expression
+** is stored is returned. When regDest<0, two identical expressions might
+** code to the same register, if they do not contain function calls and hence
+** are factored out into the initialization section at the end of the
+** prepared statement.
+*/
+int sqlite3ExprCodeRunJustOnce(
+ Parse *pParse, /* Parsing context */
+ Expr *pExpr, /* The expression to code when the VDBE initializes */
+ int regDest /* Store the value in this register */
+){
+ ExprList *p;
+ assert( ConstFactorOk(pParse) );
+ assert( regDest!=0 );
+ p = pParse->pConstExpr;
+ if( regDest<0 && p ){
+ struct ExprList_item *pItem;
+ int i;
+ for(pItem=p->a, i=p->nExpr; i>0; pItem++, i--){
+ if( pItem->fg.reusable
+ && sqlite3ExprCompare(0,pItem->pExpr,pExpr,-1)==0
+ ){
+ return pItem->u.iConstExprReg;
+ }
+ }
+ }
+ pExpr = sqlite3ExprDup(pParse->db, pExpr, 0);
+ if( pExpr!=0 && ExprHasProperty(pExpr, EP_HasFunc) ){
+ Vdbe *v = pParse->pVdbe;
+ int addr;
+ assert( v );
+ addr = sqlite3VdbeAddOp0(v, OP_Once); VdbeCoverage(v);
+ pParse->okConstFactor = 0;
+ if( !pParse->db->mallocFailed ){
+ if( regDest<0 ) regDest = ++pParse->nMem;
+ sqlite3ExprCode(pParse, pExpr, regDest);
+ }
+ pParse->okConstFactor = 1;
+ sqlite3ExprDelete(pParse->db, pExpr);
+ sqlite3VdbeJumpHere(v, addr);
+ }else{
+ p = sqlite3ExprListAppend(pParse, p, pExpr);
+ if( p ){
+ struct ExprList_item *pItem = &p->a[p->nExpr-1];
+ pItem->fg.reusable = regDest<0;
+ if( regDest<0 ) regDest = ++pParse->nMem;
+ pItem->u.iConstExprReg = regDest;
+ }
+ pParse->pConstExpr = p;
+ }
+ return regDest;
+}
+
+/*
+** 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 = sqlite3ExprSkipCollateAndLikely(pExpr);
+ if( ConstFactorOk(pParse)
+ && ALWAYS(pExpr!=0)
+ && pExpr->op!=TK_REGISTER
+ && sqlite3ExprIsConstantNotJoin(pExpr)
+ ){
+ *pReg = 0;
+ r2 = sqlite3ExprCodeRunJustOnce(pParse, pExpr, -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( pExpr==0 || !ExprHasVVAProperty(pExpr,EP_Immutable) );
+ assert( target>0 && target<=pParse->nMem );
+ assert( pParse->pVdbe!=0 || pParse->db->mallocFailed );
+ if( pParse->pVdbe==0 ) return;
+ inReg = sqlite3ExprCodeTarget(pParse, pExpr, target);
+ if( inReg!=target ){
+ u8 op;
+ Expr *pX = sqlite3ExprSkipCollateAndLikely(pExpr);
+ testcase( pX!=pExpr );
+ if( ALWAYS(pX)
+ && (ExprHasProperty(pX,EP_Subquery) || pX->op==TK_REGISTER)
+ ){
+ op = OP_Copy;
+ }else{
+ op = OP_SCopy;
+ }
+ sqlite3VdbeAddOp2(pParse->pVdbe, op, 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 && sqlite3ExprIsConstantNotJoin(pExpr) ){
+ sqlite3ExprCodeRunJustOnce(pParse, pExpr, target);
+ }else{
+ sqlite3ExprCodeCopy(pParse, pExpr, target);
+ }
+}
+
+/*
+** 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 number returned will
+** usually be pList->nExpr but might be reduced if SQLITE_ECEL_OMITREF
+** is defined.
+**
+** 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.
+** If SQLITE_ECEL_OMITREF is also set, then the values with u.x.iOrderByCol>0
+** are simply omitted rather than being copied from srcReg.
+*/
+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;
+#ifdef SQLITE_ENABLE_SORTER_REFERENCES
+ if( pItem->fg.bSorterRef ){
+ i--;
+ n--;
+ }else
+#endif
+ if( (flags & SQLITE_ECEL_REF)!=0 && (j = pItem->u.x.iOrderByCol)>0 ){
+ if( flags & SQLITE_ECEL_OMITREF ){
+ i--;
+ n--;
+ }else{
+ sqlite3VdbeAddOp2(v, copyOp, j+srcReg-1, target+i);
+ }
+ }else if( (flags & SQLITE_ECEL_FACTOR)!=0
+ && sqlite3ExprIsConstantNotJoin(pExpr)
+ ){
+ sqlite3ExprCodeRunJustOnce(pParse, pExpr, target+i);
+ }else{
+ int inReg = sqlite3ExprCodeTarget(pParse, pExpr, target+i);
+ if( inReg!=target+i ){
+ VdbeOp *pOp;
+ if( copyOp==OP_Copy
+ && (pOp=sqlite3VdbeGetLastOp(v))->opcode==OP_Copy
+ && pOp->p1+pOp->p3+1==inReg
+ && pOp->p2+pOp->p3+1==target+i
+ && pOp->p5==0 /* The do-not-merge flag must be clear */
+ ){
+ 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.
+**
+** The xJumpIf parameter determines details:
+**
+** NULL: Store the boolean result in reg[dest]
+** sqlite3ExprIfTrue: Jump to dest if true
+** sqlite3ExprIfFalse: Jump to dest if false
+**
+** The jumpIfNull parameter is ignored if xJumpIf is NULL.
+*/
+static void exprCodeBetween(
+ Parse *pParse, /* Parsing and code generating context */
+ Expr *pExpr, /* The BETWEEN expression */
+ int dest, /* Jump destination or storage location */
+ void (*xJump)(Parse*,Expr*,int,int), /* Action to take */
+ 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 */
+ int regFree1 = 0; /* Temporary use register */
+ Expr *pDel = 0;
+ sqlite3 *db = pParse->db;
+
+ memset(&compLeft, 0, sizeof(Expr));
+ memset(&compRight, 0, sizeof(Expr));
+ memset(&exprAnd, 0, sizeof(Expr));
+
+ assert( ExprUseXList(pExpr) );
+ pDel = sqlite3ExprDup(db, pExpr->pLeft, 0);
+ if( db->mallocFailed==0 ){
+ exprAnd.op = TK_AND;
+ exprAnd.pLeft = &compLeft;
+ exprAnd.pRight = &compRight;
+ compLeft.op = TK_GE;
+ compLeft.pLeft = pDel;
+ compLeft.pRight = pExpr->x.pList->a[0].pExpr;
+ compRight.op = TK_LE;
+ compRight.pLeft = pDel;
+ compRight.pRight = pExpr->x.pList->a[1].pExpr;
+ exprToRegister(pDel, exprCodeVector(pParse, pDel, &regFree1));
+ if( xJump ){
+ xJump(pParse, &exprAnd, dest, jumpIfNull);
+ }else{
+ /* Mark the expression is being from the ON or USING clause of a join
+ ** so that the sqlite3ExprCodeTarget() routine will not attempt to move
+ ** it into the Parse.pConstExpr list. We should use a new bit for this,
+ ** for clarity, but we are out of bits in the Expr.flags field so we
+ ** have to reuse the EP_OuterON bit. Bummer. */
+ pDel->flags |= EP_OuterON;
+ sqlite3ExprCodeTarget(pParse, &exprAnd, dest);
+ }
+ sqlite3ReleaseTempReg(pParse, regFree1);
+ }
+ sqlite3ExprDelete(db, pDel);
+
+ /* Ensure adequate test coverage */
+ testcase( xJump==sqlite3ExprIfTrue && jumpIfNull==0 && regFree1==0 );
+ testcase( xJump==sqlite3ExprIfTrue && jumpIfNull==0 && regFree1!=0 );
+ testcase( xJump==sqlite3ExprIfTrue && jumpIfNull!=0 && regFree1==0 );
+ testcase( xJump==sqlite3ExprIfTrue && jumpIfNull!=0 && regFree1!=0 );
+ testcase( xJump==sqlite3ExprIfFalse && jumpIfNull==0 && regFree1==0 );
+ testcase( xJump==sqlite3ExprIfFalse && jumpIfNull==0 && regFree1!=0 );
+ testcase( xJump==sqlite3ExprIfFalse && jumpIfNull!=0 && regFree1==0 );
+ testcase( xJump==sqlite3ExprIfFalse && jumpIfNull!=0 && regFree1!=0 );
+ testcase( xJump==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 */
+ assert( !ExprHasVVAProperty(pExpr, EP_Immutable) );
+ op = pExpr->op;
+ switch( op ){
+ case TK_AND:
+ case TK_OR: {
+ Expr *pAlt = sqlite3ExprSimplifiedAndOr(pExpr);
+ if( pAlt!=pExpr ){
+ sqlite3ExprIfTrue(pParse, pAlt, dest, jumpIfNull);
+ }else if( op==TK_AND ){
+ int d2 = sqlite3VdbeMakeLabel(pParse);
+ testcase( jumpIfNull==0 );
+ sqlite3ExprIfFalse(pParse, pExpr->pLeft, d2,
+ jumpIfNull^SQLITE_JUMPIFNULL);
+ sqlite3ExprIfTrue(pParse, pExpr->pRight, dest, jumpIfNull);
+ sqlite3VdbeResolveLabel(v, d2);
+ }else{
+ testcase( jumpIfNull==0 );
+ sqlite3ExprIfTrue(pParse, pExpr->pLeft, dest, jumpIfNull);
+ sqlite3ExprIfTrue(pParse, pExpr->pRight, dest, jumpIfNull);
+ }
+ break;
+ }
+ case TK_NOT: {
+ testcase( jumpIfNull==0 );
+ sqlite3ExprIfFalse(pParse, pExpr->pLeft, dest, jumpIfNull);
+ break;
+ }
+ case TK_TRUTH: {
+ int isNot; /* IS NOT TRUE or IS NOT FALSE */
+ int isTrue; /* IS TRUE or IS NOT TRUE */
+ testcase( jumpIfNull==0 );
+ isNot = pExpr->op2==TK_ISNOT;
+ isTrue = sqlite3ExprTruthValue(pExpr->pRight);
+ testcase( isTrue && isNot );
+ testcase( !isTrue && isNot );
+ if( isTrue ^ isNot ){
+ sqlite3ExprIfTrue(pParse, pExpr->pLeft, dest,
+ isNot ? SQLITE_JUMPIFNULL : 0);
+ }else{
+ sqlite3ExprIfFalse(pParse, pExpr->pLeft, dest,
+ isNot ? SQLITE_JUMPIFNULL : 0);
+ }
+ break;
+ }
+ case TK_IS:
+ case TK_ISNOT:
+ testcase( op==TK_IS );
+ testcase( op==TK_ISNOT );
+ op = (op==TK_IS) ? TK_EQ : TK_NE;
+ jumpIfNull = SQLITE_NULLEQ;
+ /* no break */ deliberate_fall_through
+ case TK_LT:
+ case TK_LE:
+ case TK_GT:
+ case TK_GE:
+ case TK_NE:
+ case TK_EQ: {
+ if( sqlite3ExprIsVector(pExpr->pLeft) ) goto default_expr;
+ testcase( jumpIfNull==0 );
+ r1 = sqlite3ExprCodeTemp(pParse, pExpr->pLeft, &regFree1);
+ r2 = sqlite3ExprCodeTemp(pParse, pExpr->pRight, &regFree2);
+ codeCompare(pParse, pExpr->pLeft, pExpr->pRight, op,
+ r1, r2, dest, jumpIfNull, ExprHasProperty(pExpr,EP_Commuted));
+ 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 && jumpIfNull==SQLITE_NULLEQ);
+ VdbeCoverageIf(v, op==OP_Eq && jumpIfNull!=SQLITE_NULLEQ);
+ assert(TK_NE==OP_Ne); testcase(op==OP_Ne);
+ VdbeCoverageIf(v, op==OP_Ne && jumpIfNull==SQLITE_NULLEQ);
+ VdbeCoverageIf(v, op==OP_Ne && jumpIfNull!=SQLITE_NULLEQ);
+ 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, &regFree1);
+ sqlite3VdbeTypeofColumn(v, r1);
+ 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, sqlite3ExprIfTrue, jumpIfNull);
+ break;
+ }
+#ifndef SQLITE_OMIT_SUBQUERY
+ case TK_IN: {
+ int destIfFalse = sqlite3VdbeMakeLabel(pParse);
+ int destIfNull = jumpIfNull ? dest : destIfFalse;
+ sqlite3ExprCodeIN(pParse, pExpr, destIfFalse, destIfNull);
+ sqlite3VdbeGoto(v, dest);
+ sqlite3VdbeResolveLabel(v, destIfFalse);
+ break;
+ }
+#endif
+ default: {
+ default_expr:
+ if( ExprAlwaysTrue(pExpr) ){
+ sqlite3VdbeGoto(v, dest);
+ }else if( ExprAlwaysFalse(pExpr) ){
+ /* No-op */
+ }else{
+ r1 = sqlite3ExprCodeTemp(pParse, pExpr, &regFree1);
+ 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;
+ assert( !ExprHasVVAProperty(pExpr,EP_Immutable) );
+
+ /* 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:
+ case TK_OR: {
+ Expr *pAlt = sqlite3ExprSimplifiedAndOr(pExpr);
+ if( pAlt!=pExpr ){
+ sqlite3ExprIfFalse(pParse, pAlt, dest, jumpIfNull);
+ }else if( pExpr->op==TK_AND ){
+ testcase( jumpIfNull==0 );
+ sqlite3ExprIfFalse(pParse, pExpr->pLeft, dest, jumpIfNull);
+ sqlite3ExprIfFalse(pParse, pExpr->pRight, dest, jumpIfNull);
+ }else{
+ int d2 = sqlite3VdbeMakeLabel(pParse);
+ testcase( jumpIfNull==0 );
+ sqlite3ExprIfTrue(pParse, pExpr->pLeft, d2,
+ jumpIfNull^SQLITE_JUMPIFNULL);
+ sqlite3ExprIfFalse(pParse, pExpr->pRight, dest, jumpIfNull);
+ sqlite3VdbeResolveLabel(v, d2);
+ }
+ break;
+ }
+ case TK_NOT: {
+ testcase( jumpIfNull==0 );
+ sqlite3ExprIfTrue(pParse, pExpr->pLeft, dest, jumpIfNull);
+ break;
+ }
+ case TK_TRUTH: {
+ int isNot; /* IS NOT TRUE or IS NOT FALSE */
+ int isTrue; /* IS TRUE or IS NOT TRUE */
+ testcase( jumpIfNull==0 );
+ isNot = pExpr->op2==TK_ISNOT;
+ isTrue = sqlite3ExprTruthValue(pExpr->pRight);
+ testcase( isTrue && isNot );
+ testcase( !isTrue && isNot );
+ if( isTrue ^ isNot ){
+ /* IS TRUE and IS NOT FALSE */
+ sqlite3ExprIfFalse(pParse, pExpr->pLeft, dest,
+ isNot ? 0 : SQLITE_JUMPIFNULL);
+
+ }else{
+ /* IS FALSE and IS NOT TRUE */
+ sqlite3ExprIfTrue(pParse, pExpr->pLeft, dest,
+ isNot ? 0 : SQLITE_JUMPIFNULL);
+ }
+ break;
+ }
+ case TK_IS:
+ case TK_ISNOT:
+ testcase( pExpr->op==TK_IS );
+ testcase( pExpr->op==TK_ISNOT );
+ op = (pExpr->op==TK_IS) ? TK_NE : TK_EQ;
+ jumpIfNull = SQLITE_NULLEQ;
+ /* no break */ deliberate_fall_through
+ case TK_LT:
+ case TK_LE:
+ case TK_GT:
+ case TK_GE:
+ case TK_NE:
+ case TK_EQ: {
+ if( sqlite3ExprIsVector(pExpr->pLeft) ) goto default_expr;
+ testcase( jumpIfNull==0 );
+ r1 = sqlite3ExprCodeTemp(pParse, pExpr->pLeft, &regFree1);
+ r2 = sqlite3ExprCodeTemp(pParse, pExpr->pRight, &regFree2);
+ codeCompare(pParse, pExpr->pLeft, pExpr->pRight, op,
+ r1, r2, dest, jumpIfNull,ExprHasProperty(pExpr,EP_Commuted));
+ 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 && jumpIfNull!=SQLITE_NULLEQ);
+ VdbeCoverageIf(v, op==OP_Eq && jumpIfNull==SQLITE_NULLEQ);
+ assert(TK_NE==OP_Ne); testcase(op==OP_Ne);
+ VdbeCoverageIf(v, op==OP_Ne && jumpIfNull!=SQLITE_NULLEQ);
+ VdbeCoverageIf(v, op==OP_Ne && jumpIfNull==SQLITE_NULLEQ);
+ testcase( regFree1==0 );
+ testcase( regFree2==0 );
+ break;
+ }
+ case TK_ISNULL:
+ case TK_NOTNULL: {
+ r1 = sqlite3ExprCodeTemp(pParse, pExpr->pLeft, &regFree1);
+ sqlite3VdbeTypeofColumn(v, r1);
+ 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, sqlite3ExprIfFalse, jumpIfNull);
+ break;
+ }
+#ifndef SQLITE_OMIT_SUBQUERY
+ case TK_IN: {
+ if( jumpIfNull ){
+ sqlite3ExprCodeIN(pParse, pExpr, dest, dest);
+ }else{
+ int destIfNull = sqlite3VdbeMakeLabel(pParse);
+ sqlite3ExprCodeIN(pParse, pExpr, dest, destIfNull);
+ sqlite3VdbeResolveLabel(v, destIfNull);
+ }
+ break;
+ }
+#endif
+ default: {
+ default_expr:
+ if( ExprAlwaysFalse(pExpr) ){
+ sqlite3VdbeGoto(v, dest);
+ }else if( ExprAlwaysTrue(pExpr) ){
+ /* no-op */
+ }else{
+ r1 = sqlite3ExprCodeTemp(pParse, pExpr, &regFree1);
+ 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);
+}
+
+/*
+** Expression pVar is guaranteed to be an SQL variable. pExpr may be any
+** type of expression.
+**
+** If pExpr is a simple SQL value - an integer, real, string, blob
+** or NULL value - then the VDBE currently being prepared is configured
+** to re-prepare each time a new value is bound to variable pVar.
+**
+** Additionally, if pExpr is a simple SQL value and the value is the
+** same as that currently bound to variable pVar, non-zero is returned.
+** Otherwise, if the values are not the same or if pExpr is not a simple
+** SQL value, zero is returned.
+*/
+static int exprCompareVariable(
+ const Parse *pParse,
+ const Expr *pVar,
+ const Expr *pExpr
+){
+ int res = 0;
+ int iVar;
+ sqlite3_value *pL, *pR = 0;
+
+ sqlite3ValueFromExpr(pParse->db, pExpr, SQLITE_UTF8, SQLITE_AFF_BLOB, &pR);
+ if( pR ){
+ iVar = pVar->iColumn;
+ sqlite3VdbeSetVarmask(pParse->pVdbe, iVar);
+ pL = sqlite3VdbeGetBoundValue(pParse->pReprepare, iVar, SQLITE_AFF_BLOB);
+ if( pL ){
+ if( sqlite3_value_type(pL)==SQLITE_TEXT ){
+ sqlite3_value_text(pL); /* Make sure the encoding is UTF-8 */
+ }
+ res = 0==sqlite3MemCompare(pL, pR, 0);
+ }
+ sqlite3ValueFree(pR);
+ sqlite3ValueFree(pL);
+ }
+
+ return res;
+}
+
+/*
+** 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.
+**
+** If pParse is not NULL then TK_VARIABLE terms in pA with bindings in
+** pParse->pReprepare can be matched against literals in pB. The
+** pParse->pVdbe->expmask bitmask is updated for each variable referenced.
+** If pParse is NULL (the normal case) then any TK_VARIABLE term in
+** Argument pParse should normally be NULL. If it is not NULL and pA or
+** pB causes a return value of 2.
+*/
+int sqlite3ExprCompare(
+ const Parse *pParse,
+ const Expr *pA,
+ const Expr *pB,
+ int iTab
+){
+ u32 combinedFlags;
+ if( pA==0 || pB==0 ){
+ return pB==pA ? 0 : 2;
+ }
+ if( pParse && pA->op==TK_VARIABLE && exprCompareVariable(pParse, pA, pB) ){
+ return 0;
+ }
+ 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 || pA->op==TK_RAISE ){
+ if( pA->op==TK_COLLATE && sqlite3ExprCompare(pParse, pA->pLeft,pB,iTab)<2 ){
+ return 1;
+ }
+ if( pB->op==TK_COLLATE && sqlite3ExprCompare(pParse, pA,pB->pLeft,iTab)<2 ){
+ return 1;
+ }
+ if( pA->op==TK_AGG_COLUMN && pB->op==TK_COLUMN
+ && pB->iTable<0 && pA->iTable==iTab
+ ){
+ /* fall through */
+ }else{
+ return 2;
+ }
+ }
+ assert( !ExprHasProperty(pA, EP_IntValue) );
+ assert( !ExprHasProperty(pB, EP_IntValue) );
+ if( pA->u.zToken ){
+ if( pA->op==TK_FUNCTION || pA->op==TK_AGG_FUNCTION ){
+ if( sqlite3StrICmp(pA->u.zToken,pB->u.zToken)!=0 ) return 2;
+#ifndef SQLITE_OMIT_WINDOWFUNC
+ assert( pA->op==pB->op );
+ if( ExprHasProperty(pA,EP_WinFunc)!=ExprHasProperty(pB,EP_WinFunc) ){
+ return 2;
+ }
+ if( ExprHasProperty(pA,EP_WinFunc) ){
+ if( sqlite3WindowCompare(pParse, pA->y.pWin, pB->y.pWin, 1)!=0 ){
+ return 2;
+ }
+ }
+#endif
+ }else if( pA->op==TK_NULL ){
+ return 0;
+ }else if( pA->op==TK_COLLATE ){
+ if( sqlite3_stricmp(pA->u.zToken,pB->u.zToken)!=0 ) return 2;
+ }else
+ if( pB->u.zToken!=0
+ && pA->op!=TK_COLUMN
+ && pA->op!=TK_AGG_COLUMN
+ && strcmp(pA->u.zToken,pB->u.zToken)!=0
+ ){
+ return 2;
+ }
+ }
+ if( (pA->flags & (EP_Distinct|EP_Commuted))
+ != (pB->flags & (EP_Distinct|EP_Commuted)) ) return 2;
+ if( ALWAYS((combinedFlags & EP_TokenOnly)==0) ){
+ if( combinedFlags & EP_xIsSelect ) return 2;
+ if( (combinedFlags & EP_FixedCol)==0
+ && sqlite3ExprCompare(pParse, pA->pLeft, pB->pLeft, iTab) ) return 2;
+ if( sqlite3ExprCompare(pParse, pA->pRight, pB->pRight, iTab) ) return 2;
+ if( sqlite3ExprListCompare(pA->x.pList, pB->x.pList, iTab) ) return 2;
+ if( pA->op!=TK_STRING
+ && pA->op!=TK_TRUEFALSE
+ && ALWAYS((combinedFlags & EP_Reduced)==0)
+ ){
+ if( pA->iColumn!=pB->iColumn ) return 2;
+ if( pA->op2!=pB->op2 && pA->op==TK_TRUTH ) return 2;
+ if( pA->op!=TK_IN && pA->iTable!=pB->iTable && pA->iTable!=iTab ){
+ return 2;
+ }
+ }
+ }
+ return 0;
+}
+
+/*
+** Compare two ExprList objects. Return 0 if they are identical, 1
+** if they are certainly different, or 2 if it is not possible to
+** determine if they are identical or not.
+**
+** 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(const ExprList *pA, const 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++){
+ int res;
+ Expr *pExprA = pA->a[i].pExpr;
+ Expr *pExprB = pB->a[i].pExpr;
+ if( pA->a[i].fg.sortFlags!=pB->a[i].fg.sortFlags ) return 1;
+ if( (res = sqlite3ExprCompare(0, pExprA, pExprB, iTab)) ) return res;
+ }
+ return 0;
+}
+
+/*
+** Like sqlite3ExprCompare() except COLLATE operators at the top-level
+** are ignored.
+*/
+int sqlite3ExprCompareSkip(Expr *pA,Expr *pB, int iTab){
+ return sqlite3ExprCompare(0,
+ sqlite3ExprSkipCollate(pA),
+ sqlite3ExprSkipCollate(pB),
+ iTab);
+}
+
+/*
+** Return non-zero if Expr p can only be true if pNN is not NULL.
+**
+** Or if seenNot is true, return non-zero if Expr p can only be
+** non-NULL if pNN is not NULL
+*/
+static int exprImpliesNotNull(
+ const Parse *pParse,/* Parsing context */
+ const Expr *p, /* The expression to be checked */
+ const Expr *pNN, /* The expression that is NOT NULL */
+ int iTab, /* Table being evaluated */
+ int seenNot /* Return true only if p can be any non-NULL value */
+){
+ assert( p );
+ assert( pNN );
+ if( sqlite3ExprCompare(pParse, p, pNN, iTab)==0 ){
+ return pNN->op!=TK_NULL;
+ }
+ switch( p->op ){
+ case TK_IN: {
+ if( seenNot && ExprHasProperty(p, EP_xIsSelect) ) return 0;
+ assert( ExprUseXSelect(p) || (p->x.pList!=0 && p->x.pList->nExpr>0) );
+ return exprImpliesNotNull(pParse, p->pLeft, pNN, iTab, 1);
+ }
+ case TK_BETWEEN: {
+ ExprList *pList;
+ assert( ExprUseXList(p) );
+ pList = p->x.pList;
+ assert( pList!=0 );
+ assert( pList->nExpr==2 );
+ if( seenNot ) return 0;
+ if( exprImpliesNotNull(pParse, pList->a[0].pExpr, pNN, iTab, 1)
+ || exprImpliesNotNull(pParse, pList->a[1].pExpr, pNN, iTab, 1)
+ ){
+ return 1;
+ }
+ return exprImpliesNotNull(pParse, p->pLeft, pNN, iTab, 1);
+ }
+ case TK_EQ:
+ case TK_NE:
+ case TK_LT:
+ case TK_LE:
+ case TK_GT:
+ case TK_GE:
+ case TK_PLUS:
+ case TK_MINUS:
+ case TK_BITOR:
+ case TK_LSHIFT:
+ case TK_RSHIFT:
+ case TK_CONCAT:
+ seenNot = 1;
+ /* no break */ deliberate_fall_through
+ case TK_STAR:
+ case TK_REM:
+ case TK_BITAND:
+ case TK_SLASH: {
+ if( exprImpliesNotNull(pParse, p->pRight, pNN, iTab, seenNot) ) return 1;
+ /* no break */ deliberate_fall_through
+ }
+ case TK_SPAN:
+ case TK_COLLATE:
+ case TK_UPLUS:
+ case TK_UMINUS: {
+ return exprImpliesNotNull(pParse, p->pLeft, pNN, iTab, seenNot);
+ }
+ case TK_TRUTH: {
+ if( seenNot ) return 0;
+ if( p->op2!=TK_IS ) return 0;
+ return exprImpliesNotNull(pParse, p->pLeft, pNN, iTab, 1);
+ }
+ case TK_BITNOT:
+ case TK_NOT: {
+ return exprImpliesNotNull(pParse, p->pLeft, pNN, iTab, 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 Result: false
+**
+** When comparing TK_COLUMN nodes between pE1 and pE2, if pE2 has
+** Expr.iTable<0 then assume a table number given by iTab.
+**
+** If pParse is not NULL, then the values of bound variables in pE1 are
+** compared against literal values in pE2 and pParse->pVdbe->expmask is
+** modified to record which bound variables are referenced. If pParse
+** is NULL, then false will be returned if pE1 contains any bound variables.
+**
+** 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(
+ const Parse *pParse,
+ const Expr *pE1,
+ const Expr *pE2,
+ int iTab
+){
+ if( sqlite3ExprCompare(pParse, pE1, pE2, iTab)==0 ){
+ return 1;
+ }
+ if( pE2->op==TK_OR
+ && (sqlite3ExprImpliesExpr(pParse, pE1, pE2->pLeft, iTab)
+ || sqlite3ExprImpliesExpr(pParse, pE1, pE2->pRight, iTab) )
+ ){
+ return 1;
+ }
+ if( pE2->op==TK_NOTNULL
+ && exprImpliesNotNull(pParse, pE1, pE2->pLeft, iTab, 0)
+ ){
+ return 1;
+ }
+ return 0;
+}
+
+/* This is a helper function to impliesNotNullRow(). In this routine,
+** set pWalker->eCode to one only if *both* of the input expressions
+** separately have the implies-not-null-row property.
+*/
+static void bothImplyNotNullRow(Walker *pWalker, Expr *pE1, Expr *pE2){
+ if( pWalker->eCode==0 ){
+ sqlite3WalkExpr(pWalker, pE1);
+ if( pWalker->eCode ){
+ pWalker->eCode = 0;
+ sqlite3WalkExpr(pWalker, pE2);
+ }
+ }
+}
+
+/*
+** This is the Expr node callback for sqlite3ExprImpliesNonNullRow().
+** If the expression node requires that the table at pWalker->iCur
+** have one or more non-NULL column, then set pWalker->eCode to 1 and abort.
+**
+** pWalker->mWFlags is non-zero if this inquiry is being undertaking on
+** behalf of a RIGHT JOIN (or FULL JOIN). That makes a difference when
+** evaluating terms in the ON clause of an inner join.
+**
+** This routine controls an optimization. False positives (setting
+** pWalker->eCode to 1 when it should not be) are deadly, but false-negatives
+** (never setting pWalker->eCode) is a harmless missed optimization.
+*/
+static int impliesNotNullRow(Walker *pWalker, Expr *pExpr){
+ testcase( pExpr->op==TK_AGG_COLUMN );
+ testcase( pExpr->op==TK_AGG_FUNCTION );
+ if( ExprHasProperty(pExpr, EP_OuterON) ) return WRC_Prune;
+ if( ExprHasProperty(pExpr, EP_InnerON) && pWalker->mWFlags ){
+ /* If iCur is used in an inner-join ON clause to the left of a
+ ** RIGHT JOIN, that does *not* mean that the table must be non-null.
+ ** But it is difficult to check for that condition precisely.
+ ** To keep things simple, any use of iCur from any inner-join is
+ ** ignored while attempting to simplify a RIGHT JOIN. */
+ return WRC_Prune;
+ }
+ switch( pExpr->op ){
+ case TK_ISNOT:
+ case TK_ISNULL:
+ case TK_NOTNULL:
+ case TK_IS:
+ case TK_VECTOR:
+ case TK_FUNCTION:
+ case TK_TRUTH:
+ case TK_CASE:
+ testcase( pExpr->op==TK_ISNOT );
+ testcase( pExpr->op==TK_ISNULL );
+ testcase( pExpr->op==TK_NOTNULL );
+ testcase( pExpr->op==TK_IS );
+ testcase( pExpr->op==TK_VECTOR );
+ testcase( pExpr->op==TK_FUNCTION );
+ testcase( pExpr->op==TK_TRUTH );
+ testcase( pExpr->op==TK_CASE );
+ return WRC_Prune;
+
+ case TK_COLUMN:
+ if( pWalker->u.iCur==pExpr->iTable ){
+ pWalker->eCode = 1;
+ return WRC_Abort;
+ }
+ return WRC_Prune;
+
+ case TK_OR:
+ case TK_AND:
+ /* Both sides of an AND or OR must separately imply non-null-row.
+ ** Consider these cases:
+ ** 1. NOT (x AND y)
+ ** 2. x OR y
+ ** If only one of x or y is non-null-row, then the overall expression
+ ** can be true if the other arm is false (case 1) or true (case 2).
+ */
+ testcase( pExpr->op==TK_OR );
+ testcase( pExpr->op==TK_AND );
+ bothImplyNotNullRow(pWalker, pExpr->pLeft, pExpr->pRight);
+ return WRC_Prune;
+
+ case TK_IN:
+ /* Beware of "x NOT IN ()" and "x NOT IN (SELECT 1 WHERE false)",
+ ** both of which can be true. But apart from these cases, if
+ ** the left-hand side of the IN is NULL then the IN itself will be
+ ** NULL. */
+ if( ExprUseXList(pExpr) && ALWAYS(pExpr->x.pList->nExpr>0) ){
+ sqlite3WalkExpr(pWalker, pExpr->pLeft);
+ }
+ return WRC_Prune;
+
+ case TK_BETWEEN:
+ /* In "x NOT BETWEEN y AND z" either x must be non-null-row or else
+ ** both y and z must be non-null row */
+ assert( ExprUseXList(pExpr) );
+ assert( pExpr->x.pList->nExpr==2 );
+ sqlite3WalkExpr(pWalker, pExpr->pLeft);
+ bothImplyNotNullRow(pWalker, pExpr->x.pList->a[0].pExpr,
+ pExpr->x.pList->a[1].pExpr);
+ return WRC_Prune;
+
+ /* Virtual tables are allowed to use constraints like x=NULL. So
+ ** a term of the form x=y does not prove that y is not null if x
+ ** is the column of a virtual table */
+ case TK_EQ:
+ case TK_NE:
+ case TK_LT:
+ case TK_LE:
+ case TK_GT:
+ case TK_GE: {
+ Expr *pLeft = pExpr->pLeft;
+ Expr *pRight = pExpr->pRight;
+ testcase( pExpr->op==TK_EQ );
+ testcase( pExpr->op==TK_NE );
+ testcase( pExpr->op==TK_LT );
+ testcase( pExpr->op==TK_LE );
+ testcase( pExpr->op==TK_GT );
+ testcase( pExpr->op==TK_GE );
+ /* The y.pTab=0 assignment in wherecode.c always happens after the
+ ** impliesNotNullRow() test */
+ assert( pLeft->op!=TK_COLUMN || ExprUseYTab(pLeft) );
+ assert( pRight->op!=TK_COLUMN || ExprUseYTab(pRight) );
+ if( (pLeft->op==TK_COLUMN
+ && ALWAYS(pLeft->y.pTab!=0)
+ && IsVirtual(pLeft->y.pTab))
+ || (pRight->op==TK_COLUMN
+ && ALWAYS(pRight->y.pTab!=0)
+ && IsVirtual(pRight->y.pTab))
+ ){
+ return WRC_Prune;
+ }
+ /* no break */ deliberate_fall_through
+ }
+ default:
+ return WRC_Continue;
+ }
+}
+
+/*
+** Return true (non-zero) if expression p can only be true if at least
+** one column of table iTab is non-null. In other words, return true
+** if expression p will always be NULL or false if every column of iTab
+** is NULL.
+**
+** False negatives are acceptable. In other words, it is ok to return
+** zero even if expression p will never be true of every column of iTab
+** is NULL. A false negative is merely a missed optimization opportunity.
+**
+** False positives are not allowed, however. A false positive may result
+** in an incorrect answer.
+**
+** Terms of p that are marked with EP_OuterON (and hence that come from
+** the ON or USING clauses of OUTER JOINS) are excluded from the analysis.
+**
+** This routine is used to check if a LEFT JOIN can be converted into
+** an ordinary JOIN. The p argument is the WHERE clause. If the WHERE
+** clause requires that some column of the right table of the LEFT JOIN
+** be non-NULL, then the LEFT JOIN can be safely converted into an
+** ordinary join.
+*/
+int sqlite3ExprImpliesNonNullRow(Expr *p, int iTab, int isRJ){
+ Walker w;
+ p = sqlite3ExprSkipCollateAndLikely(p);
+ if( p==0 ) return 0;
+ if( p->op==TK_NOTNULL ){
+ p = p->pLeft;
+ }else{
+ while( p->op==TK_AND ){
+ if( sqlite3ExprImpliesNonNullRow(p->pLeft, iTab, isRJ) ) return 1;
+ p = p->pRight;
+ }
+ }
+ w.xExprCallback = impliesNotNullRow;
+ w.xSelectCallback = 0;
+ w.xSelectCallback2 = 0;
+ w.eCode = 0;
+ w.mWFlags = isRJ!=0;
+ w.u.iCur = iTab;
+ sqlite3WalkExpr(&w, p);
+ return w.eCode;
+}
+
+/*
+** An instance of the following structure is used by the tree walker
+** to determine if an expression can be evaluated by reference to the
+** index only, without having to do a search for the corresponding
+** table entry. The IdxCover.pIdx field is the index. IdxCover.iCur
+** is the cursor for the table.
+*/
+struct IdxCover {
+ Index *pIdx; /* The index to be tested for coverage */
+ int iCur; /* Cursor number for the table corresponding to the index */
+};
+
+/*
+** Check to see if there are references to columns in table
+** pWalker->u.pIdxCover->iCur can be satisfied using the index
+** pWalker->u.pIdxCover->pIdx.
+*/
+static int exprIdxCover(Walker *pWalker, Expr *pExpr){
+ if( pExpr->op==TK_COLUMN
+ && pExpr->iTable==pWalker->u.pIdxCover->iCur
+ && sqlite3TableColumnToIndex(pWalker->u.pIdxCover->pIdx, pExpr->iColumn)<0
+ ){
+ pWalker->eCode = 1;
+ return WRC_Abort;
+ }
+ return WRC_Continue;
+}
+
+/*
+** Determine if an index pIdx on table with cursor iCur contains will
+** the expression pExpr. Return true if the index does cover the
+** expression and false if the pExpr expression references table columns
+** that are not found in the index pIdx.
+**
+** An index covering an expression means that the expression can be
+** evaluated using only the index and without having to lookup the
+** corresponding table entry.
+*/
+int sqlite3ExprCoveredByIndex(
+ Expr *pExpr, /* The index to be tested */
+ int iCur, /* The cursor number for the corresponding table */
+ Index *pIdx /* The index that might be used for coverage */
+){
+ Walker w;
+ struct IdxCover xcov;
+ memset(&w, 0, sizeof(w));
+ xcov.iCur = iCur;
+ xcov.pIdx = pIdx;
+ w.xExprCallback = exprIdxCover;
+ w.u.pIdxCover = &xcov;
+ sqlite3WalkExpr(&w, pExpr);
+ return !w.eCode;
+}
+
+
+/* Structure used to pass information throughout the Walker in order to
+** implement sqlite3ReferencesSrcList().
+*/
+struct RefSrcList {
+ sqlite3 *db; /* Database connection used for sqlite3DbRealloc() */
+ SrcList *pRef; /* Looking for references to these tables */
+ i64 nExclude; /* Number of tables to exclude from the search */
+ int *aiExclude; /* Cursor IDs for tables to exclude from the search */
+};
+
+/*
+** Walker SELECT callbacks for sqlite3ReferencesSrcList().
+**
+** When entering a new subquery on the pExpr argument, add all FROM clause
+** entries for that subquery to the exclude list.
+**
+** When leaving the subquery, remove those entries from the exclude list.
+*/
+static int selectRefEnter(Walker *pWalker, Select *pSelect){
+ struct RefSrcList *p = pWalker->u.pRefSrcList;
+ SrcList *pSrc = pSelect->pSrc;
+ i64 i, j;
+ int *piNew;
+ if( pSrc->nSrc==0 ) return WRC_Continue;
+ j = p->nExclude;
+ p->nExclude += pSrc->nSrc;
+ piNew = sqlite3DbRealloc(p->db, p->aiExclude, p->nExclude*sizeof(int));
+ if( piNew==0 ){
+ p->nExclude = 0;
+ return WRC_Abort;
+ }else{
+ p->aiExclude = piNew;
+ }
+ for(i=0; i<pSrc->nSrc; i++, j++){
+ p->aiExclude[j] = pSrc->a[i].iCursor;
+ }
+ return WRC_Continue;
+}
+static void selectRefLeave(Walker *pWalker, Select *pSelect){
+ struct RefSrcList *p = pWalker->u.pRefSrcList;
+ SrcList *pSrc = pSelect->pSrc;
+ if( p->nExclude ){
+ assert( p->nExclude>=pSrc->nSrc );
+ p->nExclude -= pSrc->nSrc;
+ }
+}
+
+/* This is the Walker EXPR callback for sqlite3ReferencesSrcList().
+**
+** Set the 0x01 bit of pWalker->eCode if there is a reference to any
+** of the tables shown in RefSrcList.pRef.
+**
+** Set the 0x02 bit of pWalker->eCode if there is a reference to a
+** table is in neither RefSrcList.pRef nor RefSrcList.aiExclude.
+*/
+static int exprRefToSrcList(Walker *pWalker, Expr *pExpr){
+ if( pExpr->op==TK_COLUMN
+ || pExpr->op==TK_AGG_COLUMN
+ ){
+ int i;
+ struct RefSrcList *p = pWalker->u.pRefSrcList;
+ SrcList *pSrc = p->pRef;
+ int nSrc = pSrc ? pSrc->nSrc : 0;
+ for(i=0; i<nSrc; i++){
+ if( pExpr->iTable==pSrc->a[i].iCursor ){
+ pWalker->eCode |= 1;
+ return WRC_Continue;
+ }
+ }
+ for(i=0; i<p->nExclude && p->aiExclude[i]!=pExpr->iTable; i++){}
+ if( i>=p->nExclude ){
+ pWalker->eCode |= 2;
+ }
+ }
+ return WRC_Continue;
+}
+
+/*
+** Check to see if pExpr references any tables in pSrcList.
+** Possible return values:
+**
+** 1 pExpr does references a table in pSrcList.
+**
+** 0 pExpr references some table that is not defined in either
+** pSrcList or in subqueries of pExpr itself.
+**
+** -1 pExpr only references no tables at all, or it only
+** references tables defined in subqueries of pExpr itself.
+**
+** As currently used, pExpr is always an aggregate function call. That
+** fact is exploited for efficiency.
+*/
+int sqlite3ReferencesSrcList(Parse *pParse, Expr *pExpr, SrcList *pSrcList){
+ Walker w;
+ struct RefSrcList x;
+ assert( pParse->db!=0 );
+ memset(&w, 0, sizeof(w));
+ memset(&x, 0, sizeof(x));
+ w.xExprCallback = exprRefToSrcList;
+ w.xSelectCallback = selectRefEnter;
+ w.xSelectCallback2 = selectRefLeave;
+ w.u.pRefSrcList = &x;
+ x.db = pParse->db;
+ x.pRef = pSrcList;
+ assert( pExpr->op==TK_AGG_FUNCTION );
+ assert( ExprUseXList(pExpr) );
+ sqlite3WalkExprList(&w, pExpr->x.pList);
+ if( pExpr->pLeft ){
+ assert( pExpr->pLeft->op==TK_ORDER );
+ assert( ExprUseXList(pExpr->pLeft) );
+ assert( pExpr->pLeft->x.pList!=0 );
+ sqlite3WalkExprList(&w, pExpr->pLeft->x.pList);
+ }
+#ifndef SQLITE_OMIT_WINDOWFUNC
+ if( ExprHasProperty(pExpr, EP_WinFunc) ){
+ sqlite3WalkExpr(&w, pExpr->y.pWin->pFilter);
+ }
+#endif
+ if( x.aiExclude ) sqlite3DbNNFreeNN(pParse->db, x.aiExclude);
+ if( w.eCode & 0x01 ){
+ return 1;
+ }else if( w.eCode ){
+ return 0;
+ }else{
+ return -1;
+ }
+}
+
+/*
+** This is a Walker expression node callback.
+**
+** For Expr nodes that contain pAggInfo pointers, make sure the AggInfo
+** object that is referenced does not refer directly to the Expr. If
+** it does, make a copy. This is done because the pExpr argument is
+** subject to change.
+**
+** The copy is scheduled for deletion using the sqlite3ExprDeferredDelete()
+** which builds on the sqlite3ParserAddCleanup() mechanism.
+*/
+static int agginfoPersistExprCb(Walker *pWalker, Expr *pExpr){
+ if( ALWAYS(!ExprHasProperty(pExpr, EP_TokenOnly|EP_Reduced))
+ && pExpr->pAggInfo!=0
+ ){
+ AggInfo *pAggInfo = pExpr->pAggInfo;
+ int iAgg = pExpr->iAgg;
+ Parse *pParse = pWalker->pParse;
+ sqlite3 *db = pParse->db;
+ assert( iAgg>=0 );
+ if( pExpr->op!=TK_AGG_FUNCTION ){
+ if( iAgg<pAggInfo->nColumn
+ && pAggInfo->aCol[iAgg].pCExpr==pExpr
+ ){
+ pExpr = sqlite3ExprDup(db, pExpr, 0);
+ if( pExpr ){
+ pAggInfo->aCol[iAgg].pCExpr = pExpr;
+ sqlite3ExprDeferredDelete(pParse, pExpr);
+ }
+ }
+ }else{
+ assert( pExpr->op==TK_AGG_FUNCTION );
+ if( ALWAYS(iAgg<pAggInfo->nFunc)
+ && pAggInfo->aFunc[iAgg].pFExpr==pExpr
+ ){
+ pExpr = sqlite3ExprDup(db, pExpr, 0);
+ if( pExpr ){
+ pAggInfo->aFunc[iAgg].pFExpr = pExpr;
+ sqlite3ExprDeferredDelete(pParse, pExpr);
+ }
+ }
+ }
+ }
+ return WRC_Continue;
+}
+
+/*
+** Initialize a Walker object so that will persist AggInfo entries referenced
+** by the tree that is walked.
+*/
+void sqlite3AggInfoPersistWalkerInit(Walker *pWalker, Parse *pParse){
+ memset(pWalker, 0, sizeof(*pWalker));
+ pWalker->pParse = pParse;
+ pWalker->xExprCallback = agginfoPersistExprCb;
+ pWalker->xSelectCallback = sqlite3SelectWalkNoop;
+}
+
+/*
+** 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;
+}
+
+/*
+** Search the AggInfo object for an aCol[] entry that has iTable and iColumn.
+** Return the index in aCol[] of the entry that describes that column.
+**
+** If no prior entry is found, create a new one and return -1. The
+** new column will have an index of pAggInfo->nColumn-1.
+*/
+static void findOrCreateAggInfoColumn(
+ Parse *pParse, /* Parsing context */
+ AggInfo *pAggInfo, /* The AggInfo object to search and/or modify */
+ Expr *pExpr /* Expr describing the column to find or insert */
+){
+ struct AggInfo_col *pCol;
+ int k;
+
+ assert( pAggInfo->iFirstReg==0 );
+ pCol = pAggInfo->aCol;
+ for(k=0; k<pAggInfo->nColumn; k++, pCol++){
+ if( pCol->pCExpr==pExpr ) return;
+ if( pCol->iTable==pExpr->iTable
+ && pCol->iColumn==pExpr->iColumn
+ && pExpr->op!=TK_IF_NULL_ROW
+ ){
+ goto fix_up_expr;
+ }
+ }
+ k = addAggInfoColumn(pParse->db, pAggInfo);
+ if( k<0 ){
+ /* OOM on resize */
+ assert( pParse->db->mallocFailed );
+ return;
+ }
+ pCol = &pAggInfo->aCol[k];
+ assert( ExprUseYTab(pExpr) );
+ pCol->pTab = pExpr->y.pTab;
+ pCol->iTable = pExpr->iTable;
+ pCol->iColumn = pExpr->iColumn;
+ pCol->iSorterColumn = -1;
+ pCol->pCExpr = pExpr;
+ if( pAggInfo->pGroupBy && pExpr->op!=TK_IF_NULL_ROW ){
+ 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++;
+ }
+fix_up_expr:
+ ExprSetVVAProperty(pExpr, EP_NoReduce);
+ assert( pExpr->pAggInfo==0 || pExpr->pAggInfo==pAggInfo );
+ pExpr->pAggInfo = pAggInfo;
+ if( pExpr->op==TK_COLUMN ){
+ pExpr->op = TK_AGG_COLUMN;
+ }
+ pExpr->iAgg = (i16)k;
+}
+
+/*
+** 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->uNC.pAggInfo;
+
+ assert( pNC->ncFlags & NC_UAggInfo );
+ assert( pAggInfo->iFirstReg==0 );
+ switch( pExpr->op ){
+ default: {
+ IndexedExpr *pIEpr;
+ Expr tmp;
+ assert( pParse->iSelfTab==0 );
+ if( (pNC->ncFlags & NC_InAggFunc)==0 ) break;
+ if( pParse->pIdxEpr==0 ) break;
+ for(pIEpr=pParse->pIdxEpr; pIEpr; pIEpr=pIEpr->pIENext){
+ int iDataCur = pIEpr->iDataCur;
+ if( iDataCur<0 ) continue;
+ if( sqlite3ExprCompare(0, pExpr, pIEpr->pExpr, iDataCur)==0 ) break;
+ }
+ if( pIEpr==0 ) break;
+ if( NEVER(!ExprUseYTab(pExpr)) ) break;
+ for(i=0; i<pSrcList->nSrc; i++){
+ if( pSrcList->a[0].iCursor==pIEpr->iDataCur ) break;
+ }
+ if( i>=pSrcList->nSrc ) break;
+ if( NEVER(pExpr->pAggInfo!=0) ) break; /* Resolved by outer context */
+ if( pParse->nErr ){ return WRC_Abort; }
+
+ /* If we reach this point, it means that expression pExpr can be
+ ** translated into a reference to an index column as described by
+ ** pIEpr.
+ */
+ memset(&tmp, 0, sizeof(tmp));
+ tmp.op = TK_AGG_COLUMN;
+ tmp.iTable = pIEpr->iIdxCur;
+ tmp.iColumn = pIEpr->iIdxCol;
+ findOrCreateAggInfoColumn(pParse, pAggInfo, &tmp);
+ if( pParse->nErr ){ return WRC_Abort; }
+ assert( pAggInfo->aCol!=0 );
+ assert( tmp.iAgg<pAggInfo->nColumn );
+ pAggInfo->aCol[tmp.iAgg].pCExpr = pExpr;
+ pExpr->pAggInfo = pAggInfo;
+ pExpr->iAgg = tmp.iAgg;
+ return WRC_Prune;
+ }
+ case TK_IF_NULL_ROW:
+ case TK_AGG_COLUMN:
+ case TK_COLUMN: {
+ testcase( pExpr->op==TK_AGG_COLUMN );
+ testcase( pExpr->op==TK_COLUMN );
+ testcase( pExpr->op==TK_IF_NULL_ROW );
+ /* Check to see if the column is in one of the tables in the FROM
+ ** clause of the aggregate query */
+ if( ALWAYS(pSrcList!=0) ){
+ SrcItem *pItem = pSrcList->a;
+ for(i=0; i<pSrcList->nSrc; i++, pItem++){
+ assert( !ExprHasProperty(pExpr, EP_TokenOnly|EP_Reduced) );
+ if( pExpr->iTable==pItem->iCursor ){
+ findOrCreateAggInfoColumn(pParse, pAggInfo, pExpr);
+ break;
+ } /* endif pExpr->iTable==pItem->iCursor */
+ } /* end loop over pSrcList */
+ }
+ return WRC_Continue;
+ }
+ case TK_AGG_FUNCTION: {
+ if( (pNC->ncFlags & NC_InAggFunc)==0
+ && pWalker->walkerDepth==pExpr->op2
+ && pExpr->pAggInfo==0
+ ){
+ /* 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( NEVER(pItem->pFExpr==pExpr) ) break;
+ if( sqlite3ExprCompare(0, pItem->pFExpr, 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 ){
+ int nArg;
+ assert( !ExprHasProperty(pExpr, EP_xIsSelect) );
+ pItem = &pAggInfo->aFunc[i];
+ pItem->pFExpr = pExpr;
+ assert( ExprUseUToken(pExpr) );
+ nArg = pExpr->x.pList ? pExpr->x.pList->nExpr : 0;
+ pItem->pFunc = sqlite3FindFunction(pParse->db,
+ pExpr->u.zToken, nArg, enc, 0);
+ assert( pItem->bOBUnique==0 );
+ if( pExpr->pLeft
+ && (pItem->pFunc->funcFlags & SQLITE_FUNC_NEEDCOLL)==0
+ ){
+ /* The NEEDCOLL test above causes any ORDER BY clause on
+ ** aggregate min() or max() to be ignored. */
+ ExprList *pOBList;
+ assert( nArg>0 );
+ assert( pExpr->pLeft->op==TK_ORDER );
+ assert( ExprUseXList(pExpr->pLeft) );
+ pItem->iOBTab = pParse->nTab++;
+ pOBList = pExpr->pLeft->x.pList;
+ assert( pOBList->nExpr>0 );
+ assert( pItem->bOBUnique==0 );
+ if( pOBList->nExpr==1
+ && nArg==1
+ && sqlite3ExprCompare(0,pOBList->a[0].pExpr,
+ pExpr->x.pList->a[0].pExpr,0)==0
+ ){
+ pItem->bOBPayload = 0;
+ pItem->bOBUnique = ExprHasProperty(pExpr, EP_Distinct);
+ }else{
+ pItem->bOBPayload = 1;
+ }
+ pItem->bUseSubtype =
+ (pItem->pFunc->funcFlags & SQLITE_SUBTYPE)!=0;
+ }else{
+ pItem->iOBTab = -1;
+ }
+ if( ExprHasProperty(pExpr, EP_Distinct) && !pItem->bOBUnique ){
+ 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;
+}
+
+/*
+** 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;
+ w.xExprCallback = analyzeAggregate;
+ w.xSelectCallback = sqlite3WalkerDepthIncrease;
+ w.xSelectCallback2 = sqlite3WalkerDepthDecrease;
+ w.walkerDepth = 0;
+ w.u.pNC = pNC;
+ w.pParse = 0;
+ 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.
+*/
+void sqlite3ReleaseTempReg(Parse *pParse, int iReg){
+ if( iReg ){
+ sqlite3VdbeReleaseRegisters(pParse, iReg, 1, 0, 0);
+ if( pParse->nTempReg<ArraySize(pParse->aTempReg) ){
+ pParse->aTempReg[pParse->nTempReg++] = iReg;
+ }
+ }
+}
+
+/*
+** Allocate or deallocate a block of nReg consecutive registers.
+*/
+int sqlite3GetTempRange(Parse *pParse, int nReg){
+ int i, n;
+ if( nReg==1 ) return sqlite3GetTempReg(pParse);
+ i = pParse->iRangeReg;
+ n = pParse->nRangeReg;
+ if( nReg<=n ){
+ pParse->iRangeReg += nReg;
+ pParse->nRangeReg -= nReg;
+ }else{
+ i = pParse->nMem+1;
+ pParse->nMem += nReg;
+ }
+ return i;
+}
+void sqlite3ReleaseTempRange(Parse *pParse, int iReg, int nReg){
+ if( nReg==1 ){
+ sqlite3ReleaseTempReg(pParse, iReg);
+ return;
+ }
+ sqlite3VdbeReleaseRegisters(pParse, iReg, nReg, 0, 0);
+ if( nReg>pParse->nRangeReg ){
+ pParse->nRangeReg = nReg;
+ pParse->iRangeReg = iReg;
+ }
+}
+
+/*
+** Mark all temporary registers as being unavailable for reuse.
+**
+** Always invoke this procedure after coding a subroutine or co-routine
+** that might be invoked from other parts of the code, to ensure that
+** the sub/co-routine does not use registers in common with the code that
+** invokes the sub/co-routine.
+*/
+void sqlite3ClearTempRegCache(Parse *pParse){
+ pParse->nTempReg = 0;
+ pParse->nRangeReg = 0;
+}
+
+/*
+** Make sure sufficient registers have been allocated so that
+** iReg is a valid register number.
+*/
+void sqlite3TouchRegister(Parse *pParse, int iReg){
+ if( pParse->nMem<iReg ) pParse->nMem = iReg;
+}
+
+#if defined(SQLITE_ENABLE_STAT4) || defined(SQLITE_DEBUG)
+/*
+** Return the latest reusable register in the set of all registers.
+** The value returned is no less than iMin. If any register iMin or
+** greater is in permanent use, then return one more than that last
+** permanent register.
+*/
+int sqlite3FirstAvailableRegister(Parse *pParse, int iMin){
+ const ExprList *pList = pParse->pConstExpr;
+ if( pList ){
+ int i;
+ for(i=0; i<pList->nExpr; i++){
+ if( pList->a[i].u.iConstExprReg>=iMin ){
+ iMin = pList->a[i].u.iConstExprReg + 1;
+ }
+ }
+ }
+ pParse->nTempReg = 0;
+ pParse->nRangeReg = 0;
+ return iMin;
+}
+#endif /* SQLITE_ENABLE_STAT4 || SQLITE_DEBUG */
+
+/*
+** Validate that no temporary register falls within the range of
+** iFirst..iLast, inclusive. This routine is only call from within assert()
+** statements.
+*/
+#ifdef SQLITE_DEBUG
+int sqlite3NoTempsInRange(Parse *pParse, int iFirst, int iLast){
+ int i;
+ if( pParse->nRangeReg>0
+ && pParse->iRangeReg+pParse->nRangeReg > iFirst
+ && pParse->iRangeReg <= iLast
+ ){
+ return 0;
+ }
+ for(i=0; i<pParse->nTempReg; i++){
+ if( pParse->aTempReg[i]>=iFirst && pParse->aTempReg[i]<=iLast ){
+ return 0;
+ }
+ }
+ if( pParse->pConstExpr ){
+ ExprList *pList = pParse->pConstExpr;
+ for(i=0; i<pList->nExpr; i++){
+ int iReg = pList->a[i].u.iConstExprReg;
+ if( iReg==0 ) continue;
+ if( iReg>=iFirst && iReg<=iLast ) return 0;
+ }
+ }
+ return 1;
+}
+#endif /* SQLITE_DEBUG */