3001 lines
95 KiB
C
3001 lines
95 KiB
C
/*
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** 2001 September 15
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**
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** The author disclaims copyright to this source code. In place of
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** a legal notice, here is a blessing:
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**
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** May you do good and not evil.
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** May you find forgiveness for yourself and forgive others.
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** May you share freely, never taking more than you give.
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**
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*************************************************************************
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** This file contains routines used for analyzing expressions and
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** for generating VDBE code that evaluates expressions in SQLite.
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**
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** $Id: expr.c,v 1.391 2008/08/22 17:34:45 drh Exp $
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*/
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#include "sqliteInt.h"
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#include <ctype.h>
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/*
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** Return the 'affinity' of the expression pExpr if any.
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**
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** If pExpr is a column, a reference to a column via an 'AS' alias,
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** or a sub-select with a column as the return value, then the
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** affinity of that column is returned. Otherwise, 0x00 is returned,
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** indicating no affinity for the expression.
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**
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** i.e. the WHERE clause expresssions in the following statements all
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** have an affinity:
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**
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** CREATE TABLE t1(a);
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** SELECT * FROM t1 WHERE a;
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** SELECT a AS b FROM t1 WHERE b;
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** SELECT * FROM t1 WHERE (select a from t1);
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*/
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char sqlite3ExprAffinity(Expr *pExpr){
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int op = pExpr->op;
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if( op==TK_SELECT ){
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return sqlite3ExprAffinity(pExpr->pSelect->pEList->a[0].pExpr);
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}
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#ifndef SQLITE_OMIT_CAST
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if( op==TK_CAST ){
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return sqlite3AffinityType(&pExpr->token);
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}
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#endif
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if( (op==TK_COLUMN || op==TK_REGISTER) && pExpr->pTab!=0 ){
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/* op==TK_REGISTER && pExpr->pTab!=0 happens when pExpr was originally
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** a TK_COLUMN but was previously evaluated and cached in a register */
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int j = pExpr->iColumn;
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if( j<0 ) return SQLITE_AFF_INTEGER;
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assert( pExpr->pTab && j<pExpr->pTab->nCol );
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return pExpr->pTab->aCol[j].affinity;
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}
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return pExpr->affinity;
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}
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/*
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** Set the collating sequence for expression pExpr to be the collating
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** sequence named by pToken. Return a pointer to the revised expression.
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** The collating sequence is marked as "explicit" using the EP_ExpCollate
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** flag. An explicit collating sequence will override implicit
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** collating sequences.
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*/
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Expr *sqlite3ExprSetColl(Parse *pParse, Expr *pExpr, Token *pCollName){
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char *zColl = 0; /* Dequoted name of collation sequence */
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CollSeq *pColl;
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sqlite3 *db = pParse->db;
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zColl = sqlite3NameFromToken(db, pCollName);
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if( pExpr && zColl ){
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pColl = sqlite3LocateCollSeq(pParse, zColl, -1);
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if( pColl ){
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pExpr->pColl = pColl;
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pExpr->flags |= EP_ExpCollate;
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}
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}
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sqlite3DbFree(db, zColl);
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return pExpr;
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}
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/*
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** Return the default collation sequence for the expression pExpr. If
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** there is no default collation type, return 0.
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*/
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CollSeq *sqlite3ExprCollSeq(Parse *pParse, Expr *pExpr){
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CollSeq *pColl = 0;
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Expr *p = pExpr;
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while( p ){
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int op;
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pColl = p->pColl;
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if( pColl ) break;
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op = p->op;
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if( (op==TK_COLUMN || op==TK_REGISTER) && p->pTab!=0 ){
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/* op==TK_REGISTER && p->pTab!=0 happens when pExpr was originally
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** a TK_COLUMN but was previously evaluated and cached in a register */
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const char *zColl;
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int j = p->iColumn;
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if( j>=0 ){
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sqlite3 *db = pParse->db;
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zColl = p->pTab->aCol[j].zColl;
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pColl = sqlite3FindCollSeq(db, ENC(db), zColl, -1, 0);
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pExpr->pColl = pColl;
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}
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break;
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}
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if( op!=TK_CAST && op!=TK_UPLUS ){
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break;
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}
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p = p->pLeft;
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}
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if( sqlite3CheckCollSeq(pParse, pColl) ){
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pColl = 0;
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}
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return pColl;
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}
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/*
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** pExpr is an operand of a comparison operator. aff2 is the
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** type affinity of the other operand. This routine returns the
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** type affinity that should be used for the comparison operator.
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*/
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char sqlite3CompareAffinity(Expr *pExpr, char aff2){
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char aff1 = sqlite3ExprAffinity(pExpr);
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if( aff1 && aff2 ){
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/* Both sides of the comparison are columns. If one has numeric
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** affinity, use that. Otherwise use no affinity.
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*/
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if( sqlite3IsNumericAffinity(aff1) || sqlite3IsNumericAffinity(aff2) ){
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return SQLITE_AFF_NUMERIC;
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}else{
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return SQLITE_AFF_NONE;
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}
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}else if( !aff1 && !aff2 ){
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/* Neither side of the comparison is a column. Compare the
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** results directly.
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*/
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return SQLITE_AFF_NONE;
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}else{
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/* One side is a column, the other is not. Use the columns affinity. */
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assert( aff1==0 || aff2==0 );
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return (aff1 + aff2);
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}
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}
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/*
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** pExpr is a comparison operator. Return the type affinity that should
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** be applied to both operands prior to doing the comparison.
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*/
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static char comparisonAffinity(Expr *pExpr){
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char aff;
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assert( pExpr->op==TK_EQ || pExpr->op==TK_IN || pExpr->op==TK_LT ||
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pExpr->op==TK_GT || pExpr->op==TK_GE || pExpr->op==TK_LE ||
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pExpr->op==TK_NE );
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assert( pExpr->pLeft );
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aff = sqlite3ExprAffinity(pExpr->pLeft);
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if( pExpr->pRight ){
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aff = sqlite3CompareAffinity(pExpr->pRight, aff);
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}
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else if( pExpr->pSelect ){
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aff = sqlite3CompareAffinity(pExpr->pSelect->pEList->a[0].pExpr, aff);
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}
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else if( !aff ){
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aff = SQLITE_AFF_NONE;
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}
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return aff;
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}
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/*
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** pExpr is a comparison expression, eg. '=', '<', IN(...) etc.
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** idx_affinity is the affinity of an indexed column. Return true
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** if the index with affinity idx_affinity may be used to implement
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** the comparison in pExpr.
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*/
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int sqlite3IndexAffinityOk(Expr *pExpr, char idx_affinity){
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char aff = comparisonAffinity(pExpr);
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switch( aff ){
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case SQLITE_AFF_NONE:
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return 1;
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case SQLITE_AFF_TEXT:
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return idx_affinity==SQLITE_AFF_TEXT;
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default:
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return sqlite3IsNumericAffinity(idx_affinity);
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}
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}
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/*
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** Return the P5 value that should be used for a binary comparison
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** opcode (OP_Eq, OP_Ge etc.) used to compare pExpr1 and pExpr2.
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*/
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static u8 binaryCompareP5(Expr *pExpr1, Expr *pExpr2, int jumpIfNull){
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u8 aff = (char)sqlite3ExprAffinity(pExpr2);
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aff = sqlite3CompareAffinity(pExpr1, aff) | jumpIfNull;
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return aff;
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}
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/*
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** Return a pointer to the collation sequence that should be used by
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** a binary comparison operator comparing pLeft and pRight.
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**
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** If the left hand expression has a collating sequence type, then it is
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** used. Otherwise the collation sequence for the right hand expression
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** is used, or the default (BINARY) if neither expression has a collating
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** type.
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**
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** Argument pRight (but not pLeft) may be a null pointer. In this case,
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** it is not considered.
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*/
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CollSeq *sqlite3BinaryCompareCollSeq(
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Parse *pParse,
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Expr *pLeft,
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Expr *pRight
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){
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CollSeq *pColl;
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assert( pLeft );
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if( pLeft->flags & EP_ExpCollate ){
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assert( pLeft->pColl );
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pColl = pLeft->pColl;
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}else if( pRight && pRight->flags & EP_ExpCollate ){
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assert( pRight->pColl );
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pColl = pRight->pColl;
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}else{
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pColl = sqlite3ExprCollSeq(pParse, pLeft);
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if( !pColl ){
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pColl = sqlite3ExprCollSeq(pParse, pRight);
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}
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}
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return pColl;
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}
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/*
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** Generate the operands for a comparison operation. Before
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** generating the code for each operand, set the EP_AnyAff
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** flag on the expression so that it will be able to used a
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** cached column value that has previously undergone an
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** affinity change.
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*/
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static void codeCompareOperands(
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Parse *pParse, /* Parsing and code generating context */
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Expr *pLeft, /* The left operand */
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int *pRegLeft, /* Register where left operand is stored */
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int *pFreeLeft, /* Free this register when done */
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Expr *pRight, /* The right operand */
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int *pRegRight, /* Register where right operand is stored */
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int *pFreeRight /* Write temp register for right operand there */
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){
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while( pLeft->op==TK_UPLUS ) pLeft = pLeft->pLeft;
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pLeft->flags |= EP_AnyAff;
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*pRegLeft = sqlite3ExprCodeTemp(pParse, pLeft, pFreeLeft);
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while( pRight->op==TK_UPLUS ) pRight = pRight->pLeft;
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pRight->flags |= EP_AnyAff;
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*pRegRight = sqlite3ExprCodeTemp(pParse, pRight, pFreeRight);
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}
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/*
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** Generate code for a comparison operator.
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*/
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static int codeCompare(
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Parse *pParse, /* The parsing (and code generating) context */
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Expr *pLeft, /* The left operand */
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Expr *pRight, /* The right operand */
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int opcode, /* The comparison opcode */
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int in1, int in2, /* Register holding operands */
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int dest, /* Jump here if true. */
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int jumpIfNull /* If true, jump if either operand is NULL */
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){
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int p5;
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int addr;
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CollSeq *p4;
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p4 = sqlite3BinaryCompareCollSeq(pParse, pLeft, pRight);
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p5 = binaryCompareP5(pLeft, pRight, jumpIfNull);
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addr = sqlite3VdbeAddOp4(pParse->pVdbe, opcode, in2, dest, in1,
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(void*)p4, P4_COLLSEQ);
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sqlite3VdbeChangeP5(pParse->pVdbe, p5);
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if( (p5 & SQLITE_AFF_MASK)!=SQLITE_AFF_NONE ){
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sqlite3ExprCacheAffinityChange(pParse, in1, 1);
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sqlite3ExprCacheAffinityChange(pParse, in2, 1);
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}
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return addr;
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}
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#if SQLITE_MAX_EXPR_DEPTH>0
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/*
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** Check that argument nHeight is less than or equal to the maximum
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** expression depth allowed. If it is not, leave an error message in
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** pParse.
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*/
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int sqlite3ExprCheckHeight(Parse *pParse, int nHeight){
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int rc = SQLITE_OK;
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int mxHeight = pParse->db->aLimit[SQLITE_LIMIT_EXPR_DEPTH];
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if( nHeight>mxHeight ){
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sqlite3ErrorMsg(pParse,
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"Expression tree is too large (maximum depth %d)", mxHeight
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);
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rc = SQLITE_ERROR;
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}
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return rc;
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}
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/* The following three functions, heightOfExpr(), heightOfExprList()
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** and heightOfSelect(), are used to determine the maximum height
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** of any expression tree referenced by the structure passed as the
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** first argument.
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**
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** If this maximum height is greater than the current value pointed
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** to by pnHeight, the second parameter, then set *pnHeight to that
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** value.
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*/
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static void heightOfExpr(Expr *p, int *pnHeight){
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if( p ){
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if( p->nHeight>*pnHeight ){
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*pnHeight = p->nHeight;
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}
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}
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}
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static void heightOfExprList(ExprList *p, int *pnHeight){
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if( p ){
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int i;
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for(i=0; i<p->nExpr; i++){
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heightOfExpr(p->a[i].pExpr, pnHeight);
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}
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}
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}
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static void heightOfSelect(Select *p, int *pnHeight){
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if( p ){
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heightOfExpr(p->pWhere, pnHeight);
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heightOfExpr(p->pHaving, pnHeight);
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heightOfExpr(p->pLimit, pnHeight);
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heightOfExpr(p->pOffset, pnHeight);
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heightOfExprList(p->pEList, pnHeight);
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heightOfExprList(p->pGroupBy, pnHeight);
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heightOfExprList(p->pOrderBy, pnHeight);
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heightOfSelect(p->pPrior, pnHeight);
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}
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}
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/*
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** Set the Expr.nHeight variable in the structure passed as an
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** argument. An expression with no children, Expr.pList or
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** Expr.pSelect member has a height of 1. Any other expression
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** has a height equal to the maximum height of any other
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** referenced Expr plus one.
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*/
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static void exprSetHeight(Expr *p){
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int nHeight = 0;
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heightOfExpr(p->pLeft, &nHeight);
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heightOfExpr(p->pRight, &nHeight);
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heightOfExprList(p->pList, &nHeight);
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heightOfSelect(p->pSelect, &nHeight);
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p->nHeight = nHeight + 1;
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}
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/*
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** Set the Expr.nHeight variable using the exprSetHeight() function. If
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** the height is greater than the maximum allowed expression depth,
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** leave an error in pParse.
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*/
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void sqlite3ExprSetHeight(Parse *pParse, Expr *p){
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exprSetHeight(p);
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sqlite3ExprCheckHeight(pParse, p->nHeight);
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}
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/*
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** Return the maximum height of any expression tree referenced
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** by the select statement passed as an argument.
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*/
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int sqlite3SelectExprHeight(Select *p){
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int nHeight = 0;
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heightOfSelect(p, &nHeight);
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return nHeight;
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}
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#else
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#define exprSetHeight(y)
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#endif /* SQLITE_MAX_EXPR_DEPTH>0 */
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/*
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** Construct a new expression node and return a pointer to it. Memory
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** for this node is obtained from sqlite3_malloc(). The calling function
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** is responsible for making sure the node eventually gets freed.
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*/
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Expr *sqlite3Expr(
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sqlite3 *db, /* Handle for sqlite3DbMallocZero() (may be null) */
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int op, /* Expression opcode */
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Expr *pLeft, /* Left operand */
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Expr *pRight, /* Right operand */
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const Token *pToken /* Argument token */
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){
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Expr *pNew;
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pNew = sqlite3DbMallocZero(db, sizeof(Expr));
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if( pNew==0 ){
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/* When malloc fails, delete pLeft and pRight. Expressions passed to
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** this function must always be allocated with sqlite3Expr() for this
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** reason.
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*/
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sqlite3ExprDelete(db, pLeft);
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sqlite3ExprDelete(db, pRight);
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return 0;
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}
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pNew->op = op;
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pNew->pLeft = pLeft;
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pNew->pRight = pRight;
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pNew->iAgg = -1;
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pNew->span.z = (u8*)"";
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if( pToken ){
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assert( pToken->dyn==0 );
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pNew->span = pNew->token = *pToken;
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}else if( pLeft ){
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if( pRight ){
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if( pRight->span.dyn==0 && pLeft->span.dyn==0 ){
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sqlite3ExprSpan(pNew, &pLeft->span, &pRight->span);
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}
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if( pRight->flags & EP_ExpCollate ){
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pNew->flags |= EP_ExpCollate;
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pNew->pColl = pRight->pColl;
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}
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}
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if( pLeft->flags & EP_ExpCollate ){
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pNew->flags |= EP_ExpCollate;
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pNew->pColl = pLeft->pColl;
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}
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}
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exprSetHeight(pNew);
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return pNew;
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}
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/*
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** Works like sqlite3Expr() except that it takes an extra Parse*
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** argument and notifies the associated connection object if malloc fails.
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*/
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Expr *sqlite3PExpr(
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Parse *pParse, /* Parsing context */
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int op, /* Expression opcode */
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Expr *pLeft, /* Left operand */
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Expr *pRight, /* Right operand */
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const Token *pToken /* Argument token */
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){
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Expr *p = sqlite3Expr(pParse->db, op, pLeft, pRight, pToken);
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if( p ){
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sqlite3ExprCheckHeight(pParse, p->nHeight);
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}
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return p;
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}
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|
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/*
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** When doing a nested parse, you can include terms in an expression
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** that look like this: #1 #2 ... These terms refer to registers
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** in the virtual machine. #N is the N-th register.
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**
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** This routine is called by the parser to deal with on of those terms.
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** It immediately generates code to store the value in a memory location.
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** The returns an expression that will code to extract the value from
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** that memory location as needed.
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*/
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Expr *sqlite3RegisterExpr(Parse *pParse, Token *pToken){
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Vdbe *v = pParse->pVdbe;
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Expr *p;
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if( pParse->nested==0 ){
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sqlite3ErrorMsg(pParse, "near \"%T\": syntax error", pToken);
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return sqlite3PExpr(pParse, TK_NULL, 0, 0, 0);
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}
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if( v==0 ) return 0;
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p = sqlite3PExpr(pParse, TK_REGISTER, 0, 0, pToken);
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if( p==0 ){
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return 0; /* Malloc failed */
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}
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p->iTable = atoi((char*)&pToken->z[1]);
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return p;
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}
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|
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/*
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** Join two expressions using an AND operator. If either expression is
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** NULL, then just return the other expression.
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*/
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Expr *sqlite3ExprAnd(sqlite3 *db, Expr *pLeft, Expr *pRight){
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if( pLeft==0 ){
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return pRight;
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}else if( pRight==0 ){
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return pLeft;
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}else{
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return sqlite3Expr(db, TK_AND, pLeft, pRight, 0);
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}
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}
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|
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/*
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** Set the Expr.span field of the given expression to span all
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** text between the two given tokens. Both tokens must be pointing
|
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** at the same string.
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*/
|
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void sqlite3ExprSpan(Expr *pExpr, Token *pLeft, Token *pRight){
|
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assert( pRight!=0 );
|
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assert( pLeft!=0 );
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if( pExpr ){
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pExpr->span.z = pLeft->z;
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|
pExpr->span.n = pRight->n + (pRight->z - pLeft->z);
|
|
}
|
|
}
|
|
|
|
/*
|
|
** Construct a new expression node for a function with multiple
|
|
** arguments.
|
|
*/
|
|
Expr *sqlite3ExprFunction(Parse *pParse, ExprList *pList, Token *pToken){
|
|
Expr *pNew;
|
|
sqlite3 *db = pParse->db;
|
|
assert( pToken );
|
|
pNew = sqlite3DbMallocZero(db, sizeof(Expr) );
|
|
if( pNew==0 ){
|
|
sqlite3ExprListDelete(db, pList); /* Avoid leaking memory when malloc fails */
|
|
return 0;
|
|
}
|
|
pNew->op = TK_FUNCTION;
|
|
pNew->pList = pList;
|
|
assert( pToken->dyn==0 );
|
|
pNew->token = *pToken;
|
|
pNew->span = pNew->token;
|
|
|
|
sqlite3ExprSetHeight(pParse, pNew);
|
|
return pNew;
|
|
}
|
|
|
|
/*
|
|
** Assign a variable number to an expression that encodes a wildcard
|
|
** in the original SQL statement.
|
|
**
|
|
** Wildcards consisting of a single "?" are assigned the next sequential
|
|
** variable number.
|
|
**
|
|
** Wildcards of the form "?nnn" are assigned the number "nnn". We make
|
|
** sure "nnn" is not too be to avoid a denial of service attack when
|
|
** the SQL statement comes from an external source.
|
|
**
|
|
** Wildcards of the form ":aaa" or "$aaa" are assigned the same number
|
|
** as the previous instance of the same wildcard. Or if this is the first
|
|
** instance of the wildcard, the next sequenial variable number is
|
|
** assigned.
|
|
*/
|
|
void sqlite3ExprAssignVarNumber(Parse *pParse, Expr *pExpr){
|
|
Token *pToken;
|
|
sqlite3 *db = pParse->db;
|
|
|
|
if( pExpr==0 ) return;
|
|
pToken = &pExpr->token;
|
|
assert( pToken->n>=1 );
|
|
assert( pToken->z!=0 );
|
|
assert( pToken->z[0]!=0 );
|
|
if( pToken->n==1 ){
|
|
/* Wildcard of the form "?". Assign the next variable number */
|
|
pExpr->iTable = ++pParse->nVar;
|
|
}else if( pToken->z[0]=='?' ){
|
|
/* Wildcard of the form "?nnn". Convert "nnn" to an integer and
|
|
** use it as the variable number */
|
|
int i;
|
|
pExpr->iTable = i = atoi((char*)&pToken->z[1]);
|
|
testcase( i==0 );
|
|
testcase( i==1 );
|
|
testcase( i==db->aLimit[SQLITE_LIMIT_VARIABLE_NUMBER]-1 );
|
|
testcase( i==db->aLimit[SQLITE_LIMIT_VARIABLE_NUMBER] );
|
|
if( i<1 || i>db->aLimit[SQLITE_LIMIT_VARIABLE_NUMBER] ){
|
|
sqlite3ErrorMsg(pParse, "variable number must be between ?1 and ?%d",
|
|
db->aLimit[SQLITE_LIMIT_VARIABLE_NUMBER]);
|
|
}
|
|
if( i>pParse->nVar ){
|
|
pParse->nVar = i;
|
|
}
|
|
}else{
|
|
/* Wildcards of the form ":aaa" or "$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
|
|
*/
|
|
int i, n;
|
|
n = pToken->n;
|
|
for(i=0; i<pParse->nVarExpr; i++){
|
|
Expr *pE;
|
|
if( (pE = pParse->apVarExpr[i])!=0
|
|
&& pE->token.n==n
|
|
&& memcmp(pE->token.z, pToken->z, n)==0 ){
|
|
pExpr->iTable = pE->iTable;
|
|
break;
|
|
}
|
|
}
|
|
if( i>=pParse->nVarExpr ){
|
|
pExpr->iTable = ++pParse->nVar;
|
|
if( pParse->nVarExpr>=pParse->nVarExprAlloc-1 ){
|
|
pParse->nVarExprAlloc += pParse->nVarExprAlloc + 10;
|
|
pParse->apVarExpr =
|
|
sqlite3DbReallocOrFree(
|
|
db,
|
|
pParse->apVarExpr,
|
|
pParse->nVarExprAlloc*sizeof(pParse->apVarExpr[0])
|
|
);
|
|
}
|
|
if( !db->mallocFailed ){
|
|
assert( pParse->apVarExpr!=0 );
|
|
pParse->apVarExpr[pParse->nVarExpr++] = pExpr;
|
|
}
|
|
}
|
|
}
|
|
if( !pParse->nErr && pParse->nVar>db->aLimit[SQLITE_LIMIT_VARIABLE_NUMBER] ){
|
|
sqlite3ErrorMsg(pParse, "too many SQL variables");
|
|
}
|
|
}
|
|
|
|
/*
|
|
** Recursively delete an expression tree.
|
|
*/
|
|
void sqlite3ExprDelete(sqlite3 *db, Expr *p){
|
|
if( p==0 ) return;
|
|
if( p->span.dyn ) sqlite3DbFree(db, (char*)p->span.z);
|
|
if( p->token.dyn ) sqlite3DbFree(db, (char*)p->token.z);
|
|
sqlite3ExprDelete(db, p->pLeft);
|
|
sqlite3ExprDelete(db, p->pRight);
|
|
sqlite3ExprListDelete(db, p->pList);
|
|
sqlite3SelectDelete(db, p->pSelect);
|
|
sqlite3DbFree(db, p);
|
|
}
|
|
|
|
/*
|
|
** The Expr.token field might be a string literal that is quoted.
|
|
** If so, remove the quotation marks.
|
|
*/
|
|
void sqlite3DequoteExpr(sqlite3 *db, Expr *p){
|
|
if( ExprHasAnyProperty(p, EP_Dequoted) ){
|
|
return;
|
|
}
|
|
ExprSetProperty(p, EP_Dequoted);
|
|
if( p->token.dyn==0 ){
|
|
sqlite3TokenCopy(db, &p->token, &p->token);
|
|
}
|
|
sqlite3Dequote((char*)p->token.z);
|
|
}
|
|
|
|
/*
|
|
** 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.
|
|
*/
|
|
Expr *sqlite3ExprDup(sqlite3 *db, Expr *p){
|
|
Expr *pNew;
|
|
if( p==0 ) return 0;
|
|
pNew = sqlite3DbMallocRaw(db, sizeof(*p) );
|
|
if( pNew==0 ) return 0;
|
|
memcpy(pNew, p, sizeof(*pNew));
|
|
if( p->token.z!=0 ){
|
|
pNew->token.z = (u8*)sqlite3DbStrNDup(db, (char*)p->token.z, p->token.n);
|
|
pNew->token.dyn = 1;
|
|
}else{
|
|
assert( pNew->token.z==0 );
|
|
}
|
|
pNew->span.z = 0;
|
|
pNew->pLeft = sqlite3ExprDup(db, p->pLeft);
|
|
pNew->pRight = sqlite3ExprDup(db, p->pRight);
|
|
pNew->pList = sqlite3ExprListDup(db, p->pList);
|
|
pNew->pSelect = sqlite3SelectDup(db, p->pSelect);
|
|
return pNew;
|
|
}
|
|
void sqlite3TokenCopy(sqlite3 *db, Token *pTo, Token *pFrom){
|
|
if( pTo->dyn ) sqlite3DbFree(db, (char*)pTo->z);
|
|
if( pFrom->z ){
|
|
pTo->n = pFrom->n;
|
|
pTo->z = (u8*)sqlite3DbStrNDup(db, (char*)pFrom->z, pFrom->n);
|
|
pTo->dyn = 1;
|
|
}else{
|
|
pTo->z = 0;
|
|
}
|
|
}
|
|
ExprList *sqlite3ExprListDup(sqlite3 *db, ExprList *p){
|
|
ExprList *pNew;
|
|
struct ExprList_item *pItem, *pOldItem;
|
|
int i;
|
|
if( p==0 ) return 0;
|
|
pNew = sqlite3DbMallocRaw(db, sizeof(*pNew) );
|
|
if( pNew==0 ) return 0;
|
|
pNew->iECursor = 0;
|
|
pNew->nExpr = pNew->nAlloc = p->nExpr;
|
|
pNew->a = pItem = sqlite3DbMallocRaw(db, p->nExpr*sizeof(p->a[0]) );
|
|
if( pItem==0 ){
|
|
sqlite3DbFree(db, pNew);
|
|
return 0;
|
|
}
|
|
pOldItem = p->a;
|
|
for(i=0; i<p->nExpr; i++, pItem++, pOldItem++){
|
|
Expr *pNewExpr, *pOldExpr;
|
|
pItem->pExpr = pNewExpr = sqlite3ExprDup(db, pOldExpr = pOldItem->pExpr);
|
|
if( pOldExpr->span.z!=0 && pNewExpr ){
|
|
/* Always make a copy of the span for top-level expressions in the
|
|
** expression list. The logic in SELECT processing that determines
|
|
** the names of columns in the result set needs this information */
|
|
sqlite3TokenCopy(db, &pNewExpr->span, &pOldExpr->span);
|
|
}
|
|
assert( pNewExpr==0 || pNewExpr->span.z!=0
|
|
|| pOldExpr->span.z==0
|
|
|| db->mallocFailed );
|
|
pItem->zName = sqlite3DbStrDup(db, pOldItem->zName);
|
|
pItem->sortOrder = pOldItem->sortOrder;
|
|
pItem->done = 0;
|
|
pItem->iCol = pOldItem->iCol;
|
|
}
|
|
return pNew;
|
|
}
|
|
|
|
/*
|
|
** If cursors, triggers, views and subqueries are all omitted from
|
|
** the build, then none of the following routines, except for
|
|
** sqlite3SelectDup(), can be called. sqlite3SelectDup() is sometimes
|
|
** called with a NULL argument.
|
|
*/
|
|
#if !defined(SQLITE_OMIT_VIEW) || !defined(SQLITE_OMIT_TRIGGER) \
|
|
|| !defined(SQLITE_OMIT_SUBQUERY)
|
|
SrcList *sqlite3SrcListDup(sqlite3 *db, SrcList *p){
|
|
SrcList *pNew;
|
|
int i;
|
|
int nByte;
|
|
if( p==0 ) return 0;
|
|
nByte = sizeof(*p) + (p->nSrc>0 ? sizeof(p->a[0]) * (p->nSrc-1) : 0);
|
|
pNew = sqlite3DbMallocRaw(db, nByte );
|
|
if( pNew==0 ) return 0;
|
|
pNew->nSrc = pNew->nAlloc = p->nSrc;
|
|
for(i=0; i<p->nSrc; i++){
|
|
struct SrcList_item *pNewItem = &pNew->a[i];
|
|
struct SrcList_item *pOldItem = &p->a[i];
|
|
Table *pTab;
|
|
pNewItem->zDatabase = sqlite3DbStrDup(db, pOldItem->zDatabase);
|
|
pNewItem->zName = sqlite3DbStrDup(db, pOldItem->zName);
|
|
pNewItem->zAlias = sqlite3DbStrDup(db, pOldItem->zAlias);
|
|
pNewItem->jointype = pOldItem->jointype;
|
|
pNewItem->iCursor = pOldItem->iCursor;
|
|
pNewItem->isPopulated = pOldItem->isPopulated;
|
|
pTab = pNewItem->pTab = pOldItem->pTab;
|
|
if( pTab ){
|
|
pTab->nRef++;
|
|
}
|
|
pNewItem->pSelect = sqlite3SelectDup(db, pOldItem->pSelect);
|
|
pNewItem->pOn = sqlite3ExprDup(db, pOldItem->pOn);
|
|
pNewItem->pUsing = sqlite3IdListDup(db, pOldItem->pUsing);
|
|
pNewItem->colUsed = pOldItem->colUsed;
|
|
}
|
|
return pNew;
|
|
}
|
|
IdList *sqlite3IdListDup(sqlite3 *db, IdList *p){
|
|
IdList *pNew;
|
|
int i;
|
|
if( p==0 ) return 0;
|
|
pNew = sqlite3DbMallocRaw(db, sizeof(*pNew) );
|
|
if( pNew==0 ) return 0;
|
|
pNew->nId = pNew->nAlloc = p->nId;
|
|
pNew->a = sqlite3DbMallocRaw(db, p->nId*sizeof(p->a[0]) );
|
|
if( pNew->a==0 ){
|
|
sqlite3DbFree(db, pNew);
|
|
return 0;
|
|
}
|
|
for(i=0; i<p->nId; i++){
|
|
struct IdList_item *pNewItem = &pNew->a[i];
|
|
struct IdList_item *pOldItem = &p->a[i];
|
|
pNewItem->zName = sqlite3DbStrDup(db, pOldItem->zName);
|
|
pNewItem->idx = pOldItem->idx;
|
|
}
|
|
return pNew;
|
|
}
|
|
Select *sqlite3SelectDup(sqlite3 *db, Select *p){
|
|
Select *pNew;
|
|
if( p==0 ) return 0;
|
|
pNew = sqlite3DbMallocRaw(db, sizeof(*p) );
|
|
if( pNew==0 ) return 0;
|
|
pNew->pEList = sqlite3ExprListDup(db, p->pEList);
|
|
pNew->pSrc = sqlite3SrcListDup(db, p->pSrc);
|
|
pNew->pWhere = sqlite3ExprDup(db, p->pWhere);
|
|
pNew->pGroupBy = sqlite3ExprListDup(db, p->pGroupBy);
|
|
pNew->pHaving = sqlite3ExprDup(db, p->pHaving);
|
|
pNew->pOrderBy = sqlite3ExprListDup(db, p->pOrderBy);
|
|
pNew->op = p->op;
|
|
pNew->pPrior = sqlite3SelectDup(db, p->pPrior);
|
|
pNew->pLimit = sqlite3ExprDup(db, p->pLimit);
|
|
pNew->pOffset = sqlite3ExprDup(db, p->pOffset);
|
|
pNew->iLimit = 0;
|
|
pNew->iOffset = 0;
|
|
pNew->selFlags = p->selFlags & ~SF_UsesEphemeral;
|
|
pNew->pRightmost = 0;
|
|
pNew->addrOpenEphm[0] = -1;
|
|
pNew->addrOpenEphm[1] = -1;
|
|
pNew->addrOpenEphm[2] = -1;
|
|
return pNew;
|
|
}
|
|
#else
|
|
Select *sqlite3SelectDup(sqlite3 *db, Select *p){
|
|
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.
|
|
*/
|
|
ExprList *sqlite3ExprListAppend(
|
|
Parse *pParse, /* Parsing context */
|
|
ExprList *pList, /* List to which to append. Might be NULL */
|
|
Expr *pExpr, /* Expression to be appended */
|
|
Token *pName /* AS keyword for the expression */
|
|
){
|
|
sqlite3 *db = pParse->db;
|
|
if( pList==0 ){
|
|
pList = sqlite3DbMallocZero(db, sizeof(ExprList) );
|
|
if( pList==0 ){
|
|
goto no_mem;
|
|
}
|
|
assert( pList->nAlloc==0 );
|
|
}
|
|
if( pList->nAlloc<=pList->nExpr ){
|
|
struct ExprList_item *a;
|
|
int n = pList->nAlloc*2 + 4;
|
|
a = sqlite3DbRealloc(db, pList->a, n*sizeof(pList->a[0]));
|
|
if( a==0 ){
|
|
goto no_mem;
|
|
}
|
|
pList->a = a;
|
|
pList->nAlloc = n;
|
|
}
|
|
assert( pList->a!=0 );
|
|
if( pExpr || pName ){
|
|
struct ExprList_item *pItem = &pList->a[pList->nExpr++];
|
|
memset(pItem, 0, sizeof(*pItem));
|
|
pItem->zName = sqlite3NameFromToken(db, pName);
|
|
pItem->pExpr = pExpr;
|
|
}
|
|
return pList;
|
|
|
|
no_mem:
|
|
/* Avoid leaking memory if malloc has failed. */
|
|
sqlite3ExprDelete(db, pExpr);
|
|
sqlite3ExprListDelete(db, pList);
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
** If the expression list pEList contains more than iLimit elements,
|
|
** leave an error message in pParse.
|
|
*/
|
|
void sqlite3ExprListCheckLength(
|
|
Parse *pParse,
|
|
ExprList *pEList,
|
|
const char *zObject
|
|
){
|
|
int mx = pParse->db->aLimit[SQLITE_LIMIT_COLUMN];
|
|
testcase( pEList && pEList->nExpr==mx );
|
|
testcase( pEList && pEList->nExpr==mx+1 );
|
|
if( pEList && pEList->nExpr>mx ){
|
|
sqlite3ErrorMsg(pParse, "too many columns in %s", zObject);
|
|
}
|
|
}
|
|
|
|
/*
|
|
** Delete an entire expression list.
|
|
*/
|
|
void sqlite3ExprListDelete(sqlite3 *db, ExprList *pList){
|
|
int i;
|
|
struct ExprList_item *pItem;
|
|
if( pList==0 ) return;
|
|
assert( pList->a!=0 || (pList->nExpr==0 && pList->nAlloc==0) );
|
|
assert( pList->nExpr<=pList->nAlloc );
|
|
for(pItem=pList->a, i=0; i<pList->nExpr; i++, pItem++){
|
|
sqlite3ExprDelete(db, pItem->pExpr);
|
|
sqlite3DbFree(db, pItem->zName);
|
|
}
|
|
sqlite3DbFree(db, pList->a);
|
|
sqlite3DbFree(db, pList);
|
|
}
|
|
|
|
/*
|
|
** These routines are Walker callbacks. Walker.u.pi is a pointer
|
|
** to an integer. These routines are checking an expression to see
|
|
** if it is a constant. Set *Walker.u.pi to 0 if the expression is
|
|
** not constant.
|
|
**
|
|
** These callback routines are used to implement the following:
|
|
**
|
|
** sqlite3ExprIsConstant()
|
|
** sqlite3ExprIsConstantNotJoin()
|
|
** sqlite3ExprIsConstantOrFunction()
|
|
**
|
|
*/
|
|
static int exprNodeIsConstant(Walker *pWalker, Expr *pExpr){
|
|
|
|
/* If pWalker->u.i is 3 then any term of the expression that comes from
|
|
** the ON or USING clauses of a join disqualifies the expression
|
|
** from being considered constant. */
|
|
if( pWalker->u.i==3 && ExprHasAnyProperty(pExpr, EP_FromJoin) ){
|
|
pWalker->u.i = 0;
|
|
return WRC_Abort;
|
|
}
|
|
|
|
switch( pExpr->op ){
|
|
/* Consider functions to be constant if all their arguments are constant
|
|
** and pWalker->u.i==2 */
|
|
case TK_FUNCTION:
|
|
if( pWalker->u.i==2 ) return 0;
|
|
/* Fall through */
|
|
case TK_ID:
|
|
case TK_COLUMN:
|
|
case TK_DOT:
|
|
case TK_AGG_FUNCTION:
|
|
case TK_AGG_COLUMN:
|
|
#ifndef SQLITE_OMIT_SUBQUERY
|
|
case TK_SELECT:
|
|
case TK_EXISTS:
|
|
testcase( pExpr->op==TK_SELECT );
|
|
testcase( pExpr->op==TK_EXISTS );
|
|
#endif
|
|
testcase( pExpr->op==TK_ID );
|
|
testcase( pExpr->op==TK_COLUMN );
|
|
testcase( pExpr->op==TK_DOT );
|
|
testcase( pExpr->op==TK_AGG_FUNCTION );
|
|
testcase( pExpr->op==TK_AGG_COLUMN );
|
|
pWalker->u.i = 0;
|
|
return WRC_Abort;
|
|
default:
|
|
return WRC_Continue;
|
|
}
|
|
}
|
|
static int selectNodeIsConstant(Walker *pWalker, Select *pSelect){
|
|
pWalker->u.i = 0;
|
|
return WRC_Abort;
|
|
}
|
|
static int exprIsConst(Expr *p, int initFlag){
|
|
Walker w;
|
|
w.u.i = initFlag;
|
|
w.xExprCallback = exprNodeIsConstant;
|
|
w.xSelectCallback = selectNodeIsConstant;
|
|
sqlite3WalkExpr(&w, p);
|
|
return w.u.i;
|
|
}
|
|
|
|
/*
|
|
** Walk an expression tree. Return 1 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);
|
|
}
|
|
|
|
/*
|
|
** Walk an expression tree. Return 1 if the expression is constant
|
|
** that does no originate from the ON or USING clauses of a join.
|
|
** Return 0 if it involves variables or function calls or terms from
|
|
** an ON or USING clause.
|
|
*/
|
|
int sqlite3ExprIsConstantNotJoin(Expr *p){
|
|
return exprIsConst(p, 3);
|
|
}
|
|
|
|
/*
|
|
** Walk an expression tree. Return 1 if the expression is constant
|
|
** or a function call with constant arguments. Return and 0 if there
|
|
** are any variables.
|
|
**
|
|
** For the purposes of this function, a double-quoted string (ex: "abc")
|
|
** is considered a variable but a single-quoted string (ex: 'abc') is
|
|
** a constant.
|
|
*/
|
|
int sqlite3ExprIsConstantOrFunction(Expr *p){
|
|
return exprIsConst(p, 2);
|
|
}
|
|
|
|
/*
|
|
** If the expression p codes a constant integer that is small enough
|
|
** to fit in a 32-bit integer, return 1 and put the value of the integer
|
|
** in *pValue. If the expression is not an integer or if it is too big
|
|
** to fit in a signed 32-bit integer, return 0 and leave *pValue unchanged.
|
|
*/
|
|
int sqlite3ExprIsInteger(Expr *p, int *pValue){
|
|
int rc = 0;
|
|
if( p->flags & EP_IntValue ){
|
|
*pValue = p->iTable;
|
|
return 1;
|
|
}
|
|
switch( p->op ){
|
|
case TK_INTEGER: {
|
|
rc = sqlite3GetInt32((char*)p->token.z, pValue);
|
|
break;
|
|
}
|
|
case TK_UPLUS: {
|
|
rc = sqlite3ExprIsInteger(p->pLeft, pValue);
|
|
break;
|
|
}
|
|
case TK_UMINUS: {
|
|
int v;
|
|
if( sqlite3ExprIsInteger(p->pLeft, &v) ){
|
|
*pValue = -v;
|
|
rc = 1;
|
|
}
|
|
break;
|
|
}
|
|
default: break;
|
|
}
|
|
if( rc ){
|
|
p->op = TK_INTEGER;
|
|
p->flags |= EP_IntValue;
|
|
p->iTable = *pValue;
|
|
}
|
|
return rc;
|
|
}
|
|
|
|
/*
|
|
** 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;
|
|
}
|
|
|
|
#ifdef SQLITE_TEST
|
|
int sqlite3_enable_in_opt = 1;
|
|
#else
|
|
#define sqlite3_enable_in_opt 1
|
|
#endif
|
|
|
|
/*
|
|
** Return true if the IN operator optimization is enabled and
|
|
** the SELECT statement p exists and is of the
|
|
** simple form:
|
|
**
|
|
** SELECT <column> FROM <table>
|
|
**
|
|
** If this is the case, it may be possible to use an existing table
|
|
** or index instead of generating an epheremal table.
|
|
*/
|
|
#ifndef SQLITE_OMIT_SUBQUERY
|
|
static int isCandidateForInOpt(Select *p){
|
|
SrcList *pSrc;
|
|
ExprList *pEList;
|
|
Table *pTab;
|
|
if( !sqlite3_enable_in_opt ) return 0; /* IN optimization must be enabled */
|
|
if( p==0 ) return 0; /* right-hand side of IN is SELECT */
|
|
if( p->pPrior ) return 0; /* Not a compound SELECT */
|
|
if( p->selFlags & (SF_Distinct|SF_Aggregate) ){
|
|
return 0; /* No DISTINCT keyword and no aggregate functions */
|
|
}
|
|
if( p->pGroupBy ) return 0; /* Has no GROUP BY clause */
|
|
if( p->pLimit ) return 0; /* Has no LIMIT clause */
|
|
if( p->pOffset ) return 0;
|
|
if( p->pWhere ) return 0; /* Has no WHERE clause */
|
|
pSrc = p->pSrc;
|
|
if( pSrc==0 ) return 0; /* A single table in the FROM clause */
|
|
if( pSrc->nSrc!=1 ) return 0;
|
|
if( pSrc->a[0].pSelect ) return 0; /* FROM clause is not a subquery */
|
|
pTab = pSrc->a[0].pTab;
|
|
if( pTab==0 ) return 0;
|
|
if( pTab->pSelect ) return 0; /* FROM clause is not a view */
|
|
if( IsVirtual(pTab) ) return 0; /* FROM clause not a virtual table */
|
|
pEList = p->pEList;
|
|
if( pEList->nExpr!=1 ) return 0; /* One column in the result set */
|
|
if( pEList->a[0].pExpr->op!=TK_COLUMN ) return 0; /* Result is a column */
|
|
return 1;
|
|
}
|
|
#endif /* SQLITE_OMIT_SUBQUERY */
|
|
|
|
/*
|
|
** This function is used by the implementation of the IN (...) operator.
|
|
** It's job is to find or create a b-tree structure that may be used
|
|
** either to test for membership of the (...) set or to iterate through
|
|
** its members, skipping duplicates.
|
|
**
|
|
** The cursor opened on the structure (database table, database index
|
|
** or ephermal table) is stored in pX->iTable before this function returns.
|
|
** The returned value indicates the structure type, as follows:
|
|
**
|
|
** IN_INDEX_ROWID - The cursor was opened on a database table.
|
|
** IN_INDEX_INDEX - The cursor was opened on a database index.
|
|
** IN_INDEX_EPH - The cursor was opened on a specially created and
|
|
** populated epheremal table.
|
|
**
|
|
** An existing structure may only be used if the SELECT is of the simple
|
|
** form:
|
|
**
|
|
** SELECT <column> FROM <table>
|
|
**
|
|
** If prNotFound parameter is 0, then the structure will be used to iterate
|
|
** through the set members, skipping any duplicates. In this case an
|
|
** epheremal table must be used unless the selected <column> is guaranteed
|
|
** to be unique - either because it is an INTEGER PRIMARY KEY or it
|
|
** is unique by virtue of a constraint or implicit index.
|
|
**
|
|
** If the prNotFound parameter is not 0, then the structure will be used
|
|
** for fast set membership tests. In this case an epheremal table must
|
|
** be used unless <column> is an INTEGER PRIMARY KEY or an index can
|
|
** be found with <column> as its left-most column.
|
|
**
|
|
** When the structure is being used for set membership tests, the user
|
|
** needs to know whether or not the structure contains an SQL NULL
|
|
** value in order to correctly evaluate expressions like "X IN (Y, Z)".
|
|
** If there is a chance that the structure may contain a NULL value at
|
|
** runtime, then a register is allocated and the register number written
|
|
** to *prNotFound. If there is no chance that the structure contains a
|
|
** NULL value, then *prNotFound is left unchanged.
|
|
**
|
|
** If a register is allocated and its location stored in *prNotFound, then
|
|
** its initial value is NULL. If the structure does not remain constant
|
|
** for the duration of the query (i.e. the set is a correlated sub-select),
|
|
** the value of the allocated register is reset to NULL each time the
|
|
** structure is repopulated. This allows the caller to use vdbe code
|
|
** equivalent to the following:
|
|
**
|
|
** if( register==NULL ){
|
|
** has_null = <test if data structure contains null>
|
|
** register = 1
|
|
** }
|
|
**
|
|
** in order to avoid running the <test if data structure contains null>
|
|
** test more often than is necessary.
|
|
*/
|
|
#ifndef SQLITE_OMIT_SUBQUERY
|
|
int sqlite3FindInIndex(Parse *pParse, Expr *pX, int *prNotFound){
|
|
Select *p;
|
|
int eType = 0;
|
|
int iTab = pParse->nTab++;
|
|
int mustBeUnique = !prNotFound;
|
|
|
|
/* The follwing if(...) expression is true if the SELECT is of the
|
|
** simple form:
|
|
**
|
|
** SELECT <column> FROM <table>
|
|
**
|
|
** If this is the case, it may be possible to use an existing table
|
|
** or index instead of generating an epheremal table.
|
|
*/
|
|
p = pX->pSelect;
|
|
if( isCandidateForInOpt(p) ){
|
|
sqlite3 *db = pParse->db;
|
|
Index *pIdx;
|
|
Expr *pExpr = p->pEList->a[0].pExpr;
|
|
int iCol = pExpr->iColumn;
|
|
Vdbe *v = sqlite3GetVdbe(pParse);
|
|
|
|
/* This function is only called from two places. In both cases the vdbe
|
|
** has already been allocated. So assume sqlite3GetVdbe() is always
|
|
** successful here.
|
|
*/
|
|
assert(v);
|
|
if( iCol<0 ){
|
|
int iMem = ++pParse->nMem;
|
|
int iAddr;
|
|
Table *pTab = p->pSrc->a[0].pTab;
|
|
int iDb = sqlite3SchemaToIndex(db, pTab->pSchema);
|
|
sqlite3VdbeUsesBtree(v, iDb);
|
|
|
|
iAddr = sqlite3VdbeAddOp1(v, OP_If, iMem);
|
|
sqlite3VdbeAddOp2(v, OP_Integer, 1, iMem);
|
|
|
|
sqlite3OpenTable(pParse, iTab, iDb, pTab, OP_OpenRead);
|
|
eType = IN_INDEX_ROWID;
|
|
|
|
sqlite3VdbeJumpHere(v, iAddr);
|
|
}else{
|
|
/* The collation sequence used by the comparison. If an index is to
|
|
** be used in place of a temp-table, it must be ordered according
|
|
** to this collation sequence.
|
|
*/
|
|
CollSeq *pReq = sqlite3BinaryCompareCollSeq(pParse, pX->pLeft, pExpr);
|
|
|
|
/* Check that the affinity that will be used to perform the
|
|
** comparison is the same as the affinity of the column. If
|
|
** it is not, it is not possible to use any index.
|
|
*/
|
|
Table *pTab = p->pSrc->a[0].pTab;
|
|
char aff = comparisonAffinity(pX);
|
|
int affinity_ok = (pTab->aCol[iCol].affinity==aff||aff==SQLITE_AFF_NONE);
|
|
|
|
for(pIdx=pTab->pIndex; pIdx && eType==0 && affinity_ok; pIdx=pIdx->pNext){
|
|
if( (pIdx->aiColumn[0]==iCol)
|
|
&& (pReq==sqlite3FindCollSeq(db, ENC(db), pIdx->azColl[0], -1, 0))
|
|
&& (!mustBeUnique || (pIdx->nColumn==1 && pIdx->onError!=OE_None))
|
|
){
|
|
int iDb;
|
|
int iMem = ++pParse->nMem;
|
|
int iAddr;
|
|
char *pKey;
|
|
|
|
pKey = (char *)sqlite3IndexKeyinfo(pParse, pIdx);
|
|
iDb = sqlite3SchemaToIndex(db, pIdx->pSchema);
|
|
sqlite3VdbeUsesBtree(v, iDb);
|
|
|
|
iAddr = sqlite3VdbeAddOp1(v, OP_If, iMem);
|
|
sqlite3VdbeAddOp2(v, OP_Integer, 1, iMem);
|
|
|
|
sqlite3VdbeAddOp2(v, OP_SetNumColumns, 0, pIdx->nColumn);
|
|
sqlite3VdbeAddOp4(v, OP_OpenRead, iTab, pIdx->tnum, iDb,
|
|
pKey,P4_KEYINFO_HANDOFF);
|
|
VdbeComment((v, "%s", pIdx->zName));
|
|
eType = IN_INDEX_INDEX;
|
|
|
|
sqlite3VdbeJumpHere(v, iAddr);
|
|
if( prNotFound && !pTab->aCol[iCol].notNull ){
|
|
*prNotFound = ++pParse->nMem;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
if( eType==0 ){
|
|
int rMayHaveNull = 0;
|
|
if( prNotFound ){
|
|
*prNotFound = rMayHaveNull = ++pParse->nMem;
|
|
}
|
|
sqlite3CodeSubselect(pParse, pX, rMayHaveNull);
|
|
eType = IN_INDEX_EPH;
|
|
}else{
|
|
pX->iTable = iTab;
|
|
}
|
|
return eType;
|
|
}
|
|
#endif
|
|
|
|
/*
|
|
** Generate code for scalar subqueries used as an expression
|
|
** and IN operators. Examples:
|
|
**
|
|
** (SELECT a FROM b) -- subquery
|
|
** EXISTS (SELECT a FROM b) -- EXISTS subquery
|
|
** x IN (4,5,11) -- IN operator with list on right-hand side
|
|
** x IN (SELECT a FROM b) -- IN operator with subquery on the right
|
|
**
|
|
** The pExpr parameter describes the expression that contains the IN
|
|
** operator or subquery.
|
|
*/
|
|
#ifndef SQLITE_OMIT_SUBQUERY
|
|
void sqlite3CodeSubselect(Parse *pParse, Expr *pExpr, int rMayHaveNull){
|
|
int testAddr = 0; /* One-time test address */
|
|
Vdbe *v = sqlite3GetVdbe(pParse);
|
|
if( v==0 ) return;
|
|
|
|
|
|
/* This code must be run in its entirety every time it is encountered
|
|
** if any of the following is true:
|
|
**
|
|
** * The right-hand side is a correlated subquery
|
|
** * The right-hand side is an expression list containing variables
|
|
** * We are inside a trigger
|
|
**
|
|
** If all of the above are false, then we can run this code just once
|
|
** save the results, and reuse the same result on subsequent invocations.
|
|
*/
|
|
if( !ExprHasAnyProperty(pExpr, EP_VarSelect) && !pParse->trigStack ){
|
|
int mem = ++pParse->nMem;
|
|
sqlite3VdbeAddOp1(v, OP_If, mem);
|
|
testAddr = sqlite3VdbeAddOp2(v, OP_Integer, 1, mem);
|
|
assert( testAddr>0 || pParse->db->mallocFailed );
|
|
}
|
|
|
|
switch( pExpr->op ){
|
|
case TK_IN: {
|
|
char affinity;
|
|
KeyInfo keyInfo;
|
|
int addr; /* Address of OP_OpenEphemeral instruction */
|
|
|
|
if( rMayHaveNull ){
|
|
sqlite3VdbeAddOp2(v, OP_Null, 0, rMayHaveNull);
|
|
}
|
|
|
|
affinity = sqlite3ExprAffinity(pExpr->pLeft);
|
|
|
|
/* Whether this is an 'x IN(SELECT...)' or an 'x IN(<exprlist>)'
|
|
** expression it is handled the same way. A virtual table is
|
|
** filled with single-field index keys representing the results
|
|
** from the SELECT or the <exprlist>.
|
|
**
|
|
** If the 'x' expression is a column value, or the SELECT...
|
|
** statement returns a column value, then the affinity of that
|
|
** column is used to build the index keys. If both 'x' and the
|
|
** SELECT... statement are columns, then numeric affinity is used
|
|
** if either column has NUMERIC or INTEGER affinity. If neither
|
|
** 'x' nor the SELECT... statement are columns, then numeric affinity
|
|
** is used.
|
|
*/
|
|
pExpr->iTable = pParse->nTab++;
|
|
addr = sqlite3VdbeAddOp2(v, OP_OpenEphemeral, pExpr->iTable, 1);
|
|
memset(&keyInfo, 0, sizeof(keyInfo));
|
|
keyInfo.nField = 1;
|
|
|
|
if( pExpr->pSelect ){
|
|
/* Case 1: expr IN (SELECT ...)
|
|
**
|
|
** Generate code to write the results of the select into the temporary
|
|
** table allocated and opened above.
|
|
*/
|
|
SelectDest dest;
|
|
ExprList *pEList;
|
|
|
|
sqlite3SelectDestInit(&dest, SRT_Set, pExpr->iTable);
|
|
dest.affinity = (int)affinity;
|
|
assert( (pExpr->iTable&0x0000FFFF)==pExpr->iTable );
|
|
if( sqlite3Select(pParse, pExpr->pSelect, &dest) ){
|
|
return;
|
|
}
|
|
pEList = pExpr->pSelect->pEList;
|
|
if( pEList && pEList->nExpr>0 ){
|
|
keyInfo.aColl[0] = sqlite3BinaryCompareCollSeq(pParse, pExpr->pLeft,
|
|
pEList->a[0].pExpr);
|
|
}
|
|
}else if( pExpr->pList ){
|
|
/* Case 2: expr IN (exprlist)
|
|
**
|
|
** For each expression, build an index key from the evaluation and
|
|
** store it in the temporary table. If <expr> is a column, then use
|
|
** that columns affinity when building index keys. If <expr> is not
|
|
** a column, use numeric affinity.
|
|
*/
|
|
int i;
|
|
ExprList *pList = pExpr->pList;
|
|
struct ExprList_item *pItem;
|
|
int r1, r2, r3;
|
|
|
|
if( !affinity ){
|
|
affinity = SQLITE_AFF_NONE;
|
|
}
|
|
keyInfo.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( testAddr && !sqlite3ExprIsConstant(pE2) ){
|
|
sqlite3VdbeChangeToNoop(v, testAddr-1, 2);
|
|
testAddr = 0;
|
|
}
|
|
|
|
/* Evaluate the expression and insert it into the temp table */
|
|
pParse->disableColCache++;
|
|
r3 = sqlite3ExprCodeTarget(pParse, pE2, r1);
|
|
assert( pParse->disableColCache>0 );
|
|
pParse->disableColCache--;
|
|
sqlite3VdbeAddOp4(v, OP_MakeRecord, r3, 1, r2, &affinity, 1);
|
|
sqlite3ExprCacheAffinityChange(pParse, r3, 1);
|
|
sqlite3VdbeAddOp2(v, OP_IdxInsert, pExpr->iTable, r2);
|
|
}
|
|
sqlite3ReleaseTempReg(pParse, r1);
|
|
sqlite3ReleaseTempReg(pParse, r2);
|
|
}
|
|
sqlite3VdbeChangeP4(v, addr, (void *)&keyInfo, P4_KEYINFO);
|
|
break;
|
|
}
|
|
|
|
case TK_EXISTS:
|
|
case TK_SELECT: {
|
|
/* This has to be a scalar SELECT. Generate code to put the
|
|
** value of this select in a memory cell and record the number
|
|
** of the memory cell in iColumn.
|
|
*/
|
|
static const Token one = { (u8*)"1", 0, 1 };
|
|
Select *pSel;
|
|
SelectDest dest;
|
|
|
|
pSel = pExpr->pSelect;
|
|
sqlite3SelectDestInit(&dest, 0, ++pParse->nMem);
|
|
if( pExpr->op==TK_SELECT ){
|
|
dest.eDest = SRT_Mem;
|
|
sqlite3VdbeAddOp2(v, OP_Null, 0, dest.iParm);
|
|
VdbeComment((v, "Init subquery result"));
|
|
}else{
|
|
dest.eDest = SRT_Exists;
|
|
sqlite3VdbeAddOp2(v, OP_Integer, 0, dest.iParm);
|
|
VdbeComment((v, "Init EXISTS result"));
|
|
}
|
|
sqlite3ExprDelete(pParse->db, pSel->pLimit);
|
|
pSel->pLimit = sqlite3PExpr(pParse, TK_INTEGER, 0, 0, &one);
|
|
if( sqlite3Select(pParse, pSel, &dest) ){
|
|
return;
|
|
}
|
|
pExpr->iColumn = dest.iParm;
|
|
break;
|
|
}
|
|
}
|
|
|
|
if( testAddr ){
|
|
sqlite3VdbeJumpHere(v, testAddr-1);
|
|
}
|
|
|
|
return;
|
|
}
|
|
#endif /* SQLITE_OMIT_SUBQUERY */
|
|
|
|
/*
|
|
** Duplicate an 8-byte value
|
|
*/
|
|
static char *dup8bytes(Vdbe *v, const char *in){
|
|
char *out = sqlite3DbMallocRaw(sqlite3VdbeDb(v), 8);
|
|
if( out ){
|
|
memcpy(out, in, 8);
|
|
}
|
|
return out;
|
|
}
|
|
|
|
/*
|
|
** 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 n, int negateFlag, int iMem){
|
|
assert( z || v==0 || sqlite3VdbeDb(v)->mallocFailed );
|
|
if( z ){
|
|
double value;
|
|
char *zV;
|
|
assert( !isdigit(z[n]) );
|
|
sqlite3AtoF(z, &value);
|
|
if( sqlite3IsNaN(value) ){
|
|
sqlite3VdbeAddOp2(v, OP_Null, 0, iMem);
|
|
}else{
|
|
if( negateFlag ) value = -value;
|
|
zV = dup8bytes(v, (char*)&value);
|
|
sqlite3VdbeAddOp4(v, OP_Real, 0, iMem, 0, zV, P4_REAL);
|
|
}
|
|
}
|
|
}
|
|
|
|
|
|
/*
|
|
** Generate an instruction that will put the integer describe by
|
|
** text 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 codeInteger(Vdbe *v, Expr *pExpr, int negFlag, int iMem){
|
|
const char *z;
|
|
if( pExpr->flags & EP_IntValue ){
|
|
int i = pExpr->iTable;
|
|
if( negFlag ) i = -i;
|
|
sqlite3VdbeAddOp2(v, OP_Integer, i, iMem);
|
|
}else if( (z = (char*)pExpr->token.z)!=0 ){
|
|
int i;
|
|
int n = pExpr->token.n;
|
|
assert( !isdigit(z[n]) );
|
|
if( sqlite3GetInt32(z, &i) ){
|
|
if( negFlag ) i = -i;
|
|
sqlite3VdbeAddOp2(v, OP_Integer, i, iMem);
|
|
}else if( sqlite3FitsIn64Bits(z, negFlag) ){
|
|
i64 value;
|
|
char *zV;
|
|
sqlite3Atoi64(z, &value);
|
|
if( negFlag ) value = -value;
|
|
zV = dup8bytes(v, (char*)&value);
|
|
sqlite3VdbeAddOp4(v, OP_Int64, 0, iMem, 0, zV, P4_INT64);
|
|
}else{
|
|
codeReal(v, z, n, negFlag, iMem);
|
|
}
|
|
}
|
|
}
|
|
|
|
|
|
/*
|
|
** Generate code that will extract the iColumn-th column from
|
|
** table pTab and store the column value in a register. An effort
|
|
** is made to store the column value in register iReg, but this is
|
|
** not guaranteed. The location of the column value is returned.
|
|
**
|
|
** 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.
|
|
**
|
|
** This routine might attempt to reuse the value of the column that
|
|
** has already been loaded into a register. The value will always
|
|
** be used if it has not undergone any affinity changes. But if
|
|
** an affinity change has occurred, then the cached value will only be
|
|
** used if allowAffChng is true.
|
|
*/
|
|
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 */
|
|
int allowAffChng /* True if prior affinity changes are OK */
|
|
){
|
|
Vdbe *v = pParse->pVdbe;
|
|
int i;
|
|
struct yColCache *p;
|
|
|
|
for(i=0, p=pParse->aColCache; i<pParse->nColCache; i++, p++){
|
|
if( p->iTable==iTable && p->iColumn==iColumn
|
|
&& (!p->affChange || allowAffChng) ){
|
|
#if 0
|
|
sqlite3VdbeAddOp0(v, OP_Noop);
|
|
VdbeComment((v, "OPT: tab%d.col%d -> r%d", iTable, iColumn, p->iReg));
|
|
#endif
|
|
return p->iReg;
|
|
}
|
|
}
|
|
assert( v!=0 );
|
|
if( iColumn<0 ){
|
|
int op = (pTab && IsVirtual(pTab)) ? OP_VRowid : OP_Rowid;
|
|
sqlite3VdbeAddOp2(v, op, iTable, iReg);
|
|
}else if( pTab==0 ){
|
|
sqlite3VdbeAddOp3(v, OP_Column, iTable, iColumn, iReg);
|
|
}else{
|
|
int op = IsVirtual(pTab) ? OP_VColumn : OP_Column;
|
|
sqlite3VdbeAddOp3(v, op, iTable, iColumn, iReg);
|
|
sqlite3ColumnDefault(v, pTab, iColumn);
|
|
#ifndef SQLITE_OMIT_FLOATING_POINT
|
|
if( pTab->aCol[iColumn].affinity==SQLITE_AFF_REAL ){
|
|
sqlite3VdbeAddOp1(v, OP_RealAffinity, iReg);
|
|
}
|
|
#endif
|
|
}
|
|
if( pParse->disableColCache==0 ){
|
|
i = pParse->iColCache;
|
|
p = &pParse->aColCache[i];
|
|
p->iTable = iTable;
|
|
p->iColumn = iColumn;
|
|
p->iReg = iReg;
|
|
p->affChange = 0;
|
|
i++;
|
|
if( i>=ArraySize(pParse->aColCache) ) i = 0;
|
|
if( i>pParse->nColCache ) pParse->nColCache = i;
|
|
pParse->iColCache = i;
|
|
}
|
|
return iReg;
|
|
}
|
|
|
|
/*
|
|
** Clear all column cache entries associated with the vdbe
|
|
** cursor with cursor number iTable.
|
|
*/
|
|
void sqlite3ExprClearColumnCache(Parse *pParse, int iTable){
|
|
if( iTable<0 ){
|
|
pParse->nColCache = 0;
|
|
pParse->iColCache = 0;
|
|
}else{
|
|
int i;
|
|
for(i=0; i<pParse->nColCache; i++){
|
|
if( pParse->aColCache[i].iTable==iTable ){
|
|
testcase( i==pParse->nColCache-1 );
|
|
pParse->aColCache[i] = pParse->aColCache[--pParse->nColCache];
|
|
pParse->iColCache = pParse->nColCache;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
/*
|
|
** Record the fact that an affinity change has occurred on iCount
|
|
** registers starting with iStart.
|
|
*/
|
|
void sqlite3ExprCacheAffinityChange(Parse *pParse, int iStart, int iCount){
|
|
int iEnd = iStart + iCount - 1;
|
|
int i;
|
|
for(i=0; i<pParse->nColCache; i++){
|
|
int r = pParse->aColCache[i].iReg;
|
|
if( r>=iStart && r<=iEnd ){
|
|
pParse->aColCache[i].affChange = 1;
|
|
}
|
|
}
|
|
}
|
|
|
|
/*
|
|
** Generate code to move content from registers iFrom...iFrom+nReg-1
|
|
** over to iTo..iTo+nReg-1. Keep the column cache up-to-date.
|
|
*/
|
|
void sqlite3ExprCodeMove(Parse *pParse, int iFrom, int iTo, int nReg){
|
|
int i;
|
|
if( iFrom==iTo ) return;
|
|
sqlite3VdbeAddOp3(pParse->pVdbe, OP_Move, iFrom, iTo, nReg);
|
|
for(i=0; i<pParse->nColCache; i++){
|
|
int x = pParse->aColCache[i].iReg;
|
|
if( x>=iFrom && x<iFrom+nReg ){
|
|
pParse->aColCache[i].iReg += iTo-iFrom;
|
|
}
|
|
}
|
|
}
|
|
|
|
/*
|
|
** Generate code to copy content from registers iFrom...iFrom+nReg-1
|
|
** over to iTo..iTo+nReg-1.
|
|
*/
|
|
void sqlite3ExprCodeCopy(Parse *pParse, int iFrom, int iTo, int nReg){
|
|
int i;
|
|
if( iFrom==iTo ) return;
|
|
for(i=0; i<nReg; i++){
|
|
sqlite3VdbeAddOp2(pParse->pVdbe, OP_Copy, iFrom+i, iTo+i);
|
|
}
|
|
}
|
|
|
|
/*
|
|
** Return true if any register in the range iFrom..iTo (inclusive)
|
|
** is used as part of the column cache.
|
|
*/
|
|
static int usedAsColumnCache(Parse *pParse, int iFrom, int iTo){
|
|
int i;
|
|
for(i=0; i<pParse->nColCache; i++){
|
|
int r = pParse->aColCache[i].iReg;
|
|
if( r>=iFrom && r<=iTo ) return 1;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
** Theres is a value in register iCurrent. We ultimately want
|
|
** the value to be in register iTarget. It might be that
|
|
** iCurrent and iTarget are the same register.
|
|
**
|
|
** We are going to modify the value, so we need to make sure it
|
|
** is not a cached register. If iCurrent is a cached register,
|
|
** then try to move the value over to iTarget. If iTarget is a
|
|
** cached register, then clear the corresponding cache line.
|
|
**
|
|
** Return the register that the value ends up in.
|
|
*/
|
|
int sqlite3ExprWritableRegister(Parse *pParse, int iCurrent, int iTarget){
|
|
int i;
|
|
assert( pParse->pVdbe!=0 );
|
|
if( !usedAsColumnCache(pParse, iCurrent, iCurrent) ){
|
|
return iCurrent;
|
|
}
|
|
if( iCurrent!=iTarget ){
|
|
sqlite3VdbeAddOp2(pParse->pVdbe, OP_SCopy, iCurrent, iTarget);
|
|
}
|
|
for(i=0; i<pParse->nColCache; i++){
|
|
if( pParse->aColCache[i].iReg==iTarget ){
|
|
pParse->aColCache[i] = pParse->aColCache[--pParse->nColCache];
|
|
pParse->iColCache = pParse->nColCache;
|
|
}
|
|
}
|
|
return iTarget;
|
|
}
|
|
|
|
/*
|
|
** If the last instruction coded is an ephemeral copy of any of
|
|
** the registers in the nReg registers beginning with iReg, then
|
|
** convert the last instruction from OP_SCopy to OP_Copy.
|
|
*/
|
|
void sqlite3ExprHardCopy(Parse *pParse, int iReg, int nReg){
|
|
int addr;
|
|
VdbeOp *pOp;
|
|
Vdbe *v;
|
|
|
|
v = pParse->pVdbe;
|
|
addr = sqlite3VdbeCurrentAddr(v);
|
|
pOp = sqlite3VdbeGetOp(v, addr-1);
|
|
assert( pOp || pParse->db->mallocFailed );
|
|
if( pOp && pOp->opcode==OP_SCopy && pOp->p1>=iReg && pOp->p1<iReg+nReg ){
|
|
pOp->opcode = OP_Copy;
|
|
}
|
|
}
|
|
|
|
/*
|
|
** 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 guaranteed that results will
|
|
** be stored in target. The result might be stored in some other
|
|
** register if it is convenient to do so. The calling function
|
|
** must check the return code and move the results to the desired
|
|
** register.
|
|
*/
|
|
int sqlite3ExprCodeTarget(Parse *pParse, Expr *pExpr, int target){
|
|
Vdbe *v = pParse->pVdbe; /* The VM under construction */
|
|
int op; /* The opcode being coded */
|
|
int inReg = target; /* Results stored in register inReg */
|
|
int regFree1 = 0; /* If non-zero free this temporary register */
|
|
int regFree2 = 0; /* If non-zero free this temporary register */
|
|
int r1, r2, r3, r4; /* Various register numbers */
|
|
|
|
assert( v!=0 || pParse->db->mallocFailed );
|
|
assert( target>0 && target<=pParse->nMem );
|
|
if( v==0 ) return 0;
|
|
|
|
if( pExpr==0 ){
|
|
op = TK_NULL;
|
|
}else{
|
|
op = pExpr->op;
|
|
}
|
|
switch( op ){
|
|
case TK_AGG_COLUMN: {
|
|
AggInfo *pAggInfo = pExpr->pAggInfo;
|
|
struct AggInfo_col *pCol = &pAggInfo->aCol[pExpr->iAgg];
|
|
if( !pAggInfo->directMode ){
|
|
assert( pCol->iMem>0 );
|
|
inReg = pCol->iMem;
|
|
break;
|
|
}else if( pAggInfo->useSortingIdx ){
|
|
sqlite3VdbeAddOp3(v, OP_Column, pAggInfo->sortingIdx,
|
|
pCol->iSorterColumn, target);
|
|
break;
|
|
}
|
|
/* Otherwise, fall thru into the TK_COLUMN case */
|
|
}
|
|
case TK_COLUMN: {
|
|
if( pExpr->iTable<0 ){
|
|
/* This only happens when coding check constraints */
|
|
assert( pParse->ckBase>0 );
|
|
inReg = pExpr->iColumn + pParse->ckBase;
|
|
}else{
|
|
testcase( (pExpr->flags & EP_AnyAff)!=0 );
|
|
inReg = sqlite3ExprCodeGetColumn(pParse, pExpr->pTab,
|
|
pExpr->iColumn, pExpr->iTable, target,
|
|
pExpr->flags & EP_AnyAff);
|
|
}
|
|
break;
|
|
}
|
|
case TK_INTEGER: {
|
|
codeInteger(v, pExpr, 0, target);
|
|
break;
|
|
}
|
|
case TK_FLOAT: {
|
|
codeReal(v, (char*)pExpr->token.z, pExpr->token.n, 0, target);
|
|
break;
|
|
}
|
|
case TK_STRING: {
|
|
sqlite3DequoteExpr(pParse->db, pExpr);
|
|
sqlite3VdbeAddOp4(v,OP_String8, 0, target, 0,
|
|
(char*)pExpr->token.z, pExpr->token.n);
|
|
break;
|
|
}
|
|
case TK_NULL: {
|
|
sqlite3VdbeAddOp2(v, OP_Null, 0, target);
|
|
break;
|
|
}
|
|
#ifndef SQLITE_OMIT_BLOB_LITERAL
|
|
case TK_BLOB: {
|
|
int n;
|
|
const char *z;
|
|
char *zBlob;
|
|
assert( pExpr->token.n>=3 );
|
|
assert( pExpr->token.z[0]=='x' || pExpr->token.z[0]=='X' );
|
|
assert( pExpr->token.z[1]=='\'' );
|
|
assert( pExpr->token.z[pExpr->token.n-1]=='\'' );
|
|
n = pExpr->token.n - 3;
|
|
z = (char*)pExpr->token.z + 2;
|
|
zBlob = sqlite3HexToBlob(sqlite3VdbeDb(v), z, n);
|
|
sqlite3VdbeAddOp4(v, OP_Blob, n/2, target, 0, zBlob, P4_DYNAMIC);
|
|
break;
|
|
}
|
|
#endif
|
|
case TK_VARIABLE: {
|
|
sqlite3VdbeAddOp2(v, OP_Variable, pExpr->iTable, target);
|
|
if( pExpr->token.n>1 ){
|
|
sqlite3VdbeChangeP4(v, -1, (char*)pExpr->token.z, pExpr->token.n);
|
|
}
|
|
break;
|
|
}
|
|
case TK_REGISTER: {
|
|
inReg = pExpr->iTable;
|
|
break;
|
|
}
|
|
#ifndef SQLITE_OMIT_CAST
|
|
case TK_CAST: {
|
|
/* Expressions of the form: CAST(pLeft AS token) */
|
|
int aff, to_op;
|
|
inReg = sqlite3ExprCodeTarget(pParse, pExpr->pLeft, target);
|
|
aff = sqlite3AffinityType(&pExpr->token);
|
|
to_op = aff - SQLITE_AFF_TEXT + OP_ToText;
|
|
assert( to_op==OP_ToText || aff!=SQLITE_AFF_TEXT );
|
|
assert( to_op==OP_ToBlob || aff!=SQLITE_AFF_NONE );
|
|
assert( to_op==OP_ToNumeric || aff!=SQLITE_AFF_NUMERIC );
|
|
assert( to_op==OP_ToInt || aff!=SQLITE_AFF_INTEGER );
|
|
assert( to_op==OP_ToReal || aff!=SQLITE_AFF_REAL );
|
|
testcase( to_op==OP_ToText );
|
|
testcase( to_op==OP_ToBlob );
|
|
testcase( to_op==OP_ToNumeric );
|
|
testcase( to_op==OP_ToInt );
|
|
testcase( to_op==OP_ToReal );
|
|
sqlite3VdbeAddOp1(v, to_op, inReg);
|
|
testcase( usedAsColumnCache(pParse, inReg, inReg) );
|
|
sqlite3ExprCacheAffinityChange(pParse, inReg, 1);
|
|
break;
|
|
}
|
|
#endif /* SQLITE_OMIT_CAST */
|
|
case TK_LT:
|
|
case TK_LE:
|
|
case TK_GT:
|
|
case TK_GE:
|
|
case TK_NE:
|
|
case TK_EQ: {
|
|
assert( TK_LT==OP_Lt );
|
|
assert( TK_LE==OP_Le );
|
|
assert( TK_GT==OP_Gt );
|
|
assert( TK_GE==OP_Ge );
|
|
assert( TK_EQ==OP_Eq );
|
|
assert( TK_NE==OP_Ne );
|
|
testcase( op==TK_LT );
|
|
testcase( op==TK_LE );
|
|
testcase( op==TK_GT );
|
|
testcase( op==TK_GE );
|
|
testcase( op==TK_EQ );
|
|
testcase( op==TK_NE );
|
|
codeCompareOperands(pParse, pExpr->pLeft, &r1, ®Free1,
|
|
pExpr->pRight, &r2, ®Free2);
|
|
codeCompare(pParse, pExpr->pLeft, pExpr->pRight, op,
|
|
r1, r2, inReg, SQLITE_STOREP2);
|
|
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 );
|
|
assert( TK_OR==OP_Or );
|
|
assert( TK_PLUS==OP_Add );
|
|
assert( TK_MINUS==OP_Subtract );
|
|
assert( TK_REM==OP_Remainder );
|
|
assert( TK_BITAND==OP_BitAnd );
|
|
assert( TK_BITOR==OP_BitOr );
|
|
assert( TK_SLASH==OP_Divide );
|
|
assert( TK_LSHIFT==OP_ShiftLeft );
|
|
assert( TK_RSHIFT==OP_ShiftRight );
|
|
assert( TK_CONCAT==OP_Concat );
|
|
testcase( op==TK_AND );
|
|
testcase( op==TK_OR );
|
|
testcase( op==TK_PLUS );
|
|
testcase( op==TK_MINUS );
|
|
testcase( op==TK_REM );
|
|
testcase( op==TK_BITAND );
|
|
testcase( op==TK_BITOR );
|
|
testcase( op==TK_SLASH );
|
|
testcase( op==TK_LSHIFT );
|
|
testcase( op==TK_RSHIFT );
|
|
testcase( op==TK_CONCAT );
|
|
r1 = sqlite3ExprCodeTemp(pParse, pExpr->pLeft, ®Free1);
|
|
r2 = sqlite3ExprCodeTemp(pParse, pExpr->pRight, ®Free2);
|
|
sqlite3VdbeAddOp3(v, op, r2, r1, target);
|
|
testcase( regFree1==0 );
|
|
testcase( regFree2==0 );
|
|
break;
|
|
}
|
|
case TK_UMINUS: {
|
|
Expr *pLeft = pExpr->pLeft;
|
|
assert( pLeft );
|
|
if( pLeft->op==TK_FLOAT || pLeft->op==TK_INTEGER ){
|
|
if( pLeft->op==TK_FLOAT ){
|
|
codeReal(v, (char*)pLeft->token.z, pLeft->token.n, 1, target);
|
|
}else{
|
|
codeInteger(v, pLeft, 1, target);
|
|
}
|
|
}else{
|
|
regFree1 = r1 = sqlite3GetTempReg(pParse);
|
|
sqlite3VdbeAddOp2(v, OP_Integer, 0, r1);
|
|
r2 = sqlite3ExprCodeTemp(pParse, pExpr->pLeft, ®Free2);
|
|
sqlite3VdbeAddOp3(v, OP_Subtract, r2, r1, target);
|
|
testcase( regFree2==0 );
|
|
}
|
|
inReg = target;
|
|
break;
|
|
}
|
|
case TK_BITNOT:
|
|
case TK_NOT: {
|
|
assert( TK_BITNOT==OP_BitNot );
|
|
assert( TK_NOT==OP_Not );
|
|
testcase( op==TK_BITNOT );
|
|
testcase( op==TK_NOT );
|
|
inReg = sqlite3ExprCodeTarget(pParse, pExpr->pLeft, target);
|
|
testcase( inReg==target );
|
|
testcase( usedAsColumnCache(pParse, inReg, inReg) );
|
|
inReg = sqlite3ExprWritableRegister(pParse, inReg, target);
|
|
sqlite3VdbeAddOp1(v, op, inReg);
|
|
break;
|
|
}
|
|
case TK_ISNULL:
|
|
case TK_NOTNULL: {
|
|
int addr;
|
|
assert( TK_ISNULL==OP_IsNull );
|
|
assert( TK_NOTNULL==OP_NotNull );
|
|
testcase( op==TK_ISNULL );
|
|
testcase( op==TK_NOTNULL );
|
|
sqlite3VdbeAddOp2(v, OP_Integer, 1, target);
|
|
r1 = sqlite3ExprCodeTemp(pParse, pExpr->pLeft, ®Free1);
|
|
testcase( regFree1==0 );
|
|
addr = sqlite3VdbeAddOp1(v, op, r1);
|
|
sqlite3VdbeAddOp2(v, OP_AddImm, target, -1);
|
|
sqlite3VdbeJumpHere(v, addr);
|
|
break;
|
|
}
|
|
case TK_AGG_FUNCTION: {
|
|
AggInfo *pInfo = pExpr->pAggInfo;
|
|
if( pInfo==0 ){
|
|
sqlite3ErrorMsg(pParse, "misuse of aggregate: %T",
|
|
&pExpr->span);
|
|
}else{
|
|
inReg = pInfo->aFunc[pExpr->iAgg].iMem;
|
|
}
|
|
break;
|
|
}
|
|
case TK_CONST_FUNC:
|
|
case TK_FUNCTION: {
|
|
ExprList *pList = pExpr->pList;
|
|
int nExpr = pList ? pList->nExpr : 0;
|
|
FuncDef *pDef;
|
|
int nId;
|
|
const char *zId;
|
|
int constMask = 0;
|
|
int i;
|
|
sqlite3 *db = pParse->db;
|
|
u8 enc = ENC(db);
|
|
CollSeq *pColl = 0;
|
|
|
|
testcase( op==TK_CONST_FUNC );
|
|
testcase( op==TK_FUNCTION );
|
|
zId = (char*)pExpr->token.z;
|
|
nId = pExpr->token.n;
|
|
pDef = sqlite3FindFunction(pParse->db, zId, nId, nExpr, enc, 0);
|
|
assert( pDef!=0 );
|
|
if( pList ){
|
|
nExpr = pList->nExpr;
|
|
r1 = sqlite3GetTempRange(pParse, nExpr);
|
|
sqlite3ExprCodeExprList(pParse, pList, r1, 1);
|
|
}else{
|
|
nExpr = 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( nExpr>=2 && (pExpr->flags & EP_InfixFunc) ){
|
|
pDef = sqlite3VtabOverloadFunction(db, pDef, nExpr, pList->a[1].pExpr);
|
|
}else if( nExpr>0 ){
|
|
pDef = sqlite3VtabOverloadFunction(db, pDef, nExpr, pList->a[0].pExpr);
|
|
}
|
|
#endif
|
|
for(i=0; i<nExpr && i<32; i++){
|
|
if( sqlite3ExprIsConstant(pList->a[i].pExpr) ){
|
|
constMask |= (1<<i);
|
|
}
|
|
if( pDef->needCollSeq && !pColl ){
|
|
pColl = sqlite3ExprCollSeq(pParse, pList->a[i].pExpr);
|
|
}
|
|
}
|
|
if( pDef->needCollSeq ){
|
|
if( !pColl ) pColl = pParse->db->pDfltColl;
|
|
sqlite3VdbeAddOp4(v, OP_CollSeq, 0, 0, 0, (char *)pColl, P4_COLLSEQ);
|
|
}
|
|
sqlite3VdbeAddOp4(v, OP_Function, constMask, r1, target,
|
|
(char*)pDef, P4_FUNCDEF);
|
|
sqlite3VdbeChangeP5(v, nExpr);
|
|
if( nExpr ){
|
|
sqlite3ReleaseTempRange(pParse, r1, nExpr);
|
|
}
|
|
sqlite3ExprCacheAffinityChange(pParse, r1, nExpr);
|
|
break;
|
|
}
|
|
#ifndef SQLITE_OMIT_SUBQUERY
|
|
case TK_EXISTS:
|
|
case TK_SELECT: {
|
|
testcase( op==TK_EXISTS );
|
|
testcase( op==TK_SELECT );
|
|
if( pExpr->iColumn==0 ){
|
|
sqlite3CodeSubselect(pParse, pExpr, 0);
|
|
}
|
|
inReg = pExpr->iColumn;
|
|
break;
|
|
}
|
|
case TK_IN: {
|
|
int rNotFound = 0;
|
|
int rMayHaveNull = 0;
|
|
int j2, j3, j4, j5;
|
|
char affinity;
|
|
int eType;
|
|
|
|
VdbeNoopComment((v, "begin IN expr r%d", target));
|
|
eType = sqlite3FindInIndex(pParse, pExpr, &rMayHaveNull);
|
|
if( rMayHaveNull ){
|
|
rNotFound = ++pParse->nMem;
|
|
}
|
|
|
|
/* Figure out the affinity to use to create a key from the results
|
|
** of the expression. affinityStr stores a static string suitable for
|
|
** P4 of OP_MakeRecord.
|
|
*/
|
|
affinity = comparisonAffinity(pExpr);
|
|
|
|
|
|
/* Code the <expr> from "<expr> IN (...)". The temporary table
|
|
** pExpr->iTable contains the values that make up the (...) set.
|
|
*/
|
|
pParse->disableColCache++;
|
|
sqlite3ExprCode(pParse, pExpr->pLeft, target);
|
|
pParse->disableColCache--;
|
|
j2 = sqlite3VdbeAddOp1(v, OP_IsNull, target);
|
|
if( eType==IN_INDEX_ROWID ){
|
|
j3 = sqlite3VdbeAddOp1(v, OP_MustBeInt, target);
|
|
j4 = sqlite3VdbeAddOp3(v, OP_NotExists, pExpr->iTable, 0, target);
|
|
sqlite3VdbeAddOp2(v, OP_Integer, 1, target);
|
|
j5 = sqlite3VdbeAddOp0(v, OP_Goto);
|
|
sqlite3VdbeJumpHere(v, j3);
|
|
sqlite3VdbeJumpHere(v, j4);
|
|
sqlite3VdbeAddOp2(v, OP_Integer, 0, target);
|
|
}else{
|
|
r2 = regFree2 = sqlite3GetTempReg(pParse);
|
|
|
|
/* Create a record and test for set membership. If the set contains
|
|
** the value, then jump to the end of the test code. The target
|
|
** register still contains the true (1) value written to it earlier.
|
|
*/
|
|
sqlite3VdbeAddOp4(v, OP_MakeRecord, target, 1, r2, &affinity, 1);
|
|
sqlite3VdbeAddOp2(v, OP_Integer, 1, target);
|
|
j5 = sqlite3VdbeAddOp3(v, OP_Found, pExpr->iTable, 0, r2);
|
|
|
|
/* If the set membership test fails, then the result of the
|
|
** "x IN (...)" expression must be either 0 or NULL. If the set
|
|
** contains no NULL values, then the result is 0. If the set
|
|
** contains one or more NULL values, then the result of the
|
|
** expression is also NULL.
|
|
*/
|
|
if( rNotFound==0 ){
|
|
/* This branch runs if it is known at compile time (now) that
|
|
** the set contains no NULL values. This happens as the result
|
|
** of a "NOT NULL" constraint in the database schema. No need
|
|
** to test the data structure at runtime in this case.
|
|
*/
|
|
sqlite3VdbeAddOp2(v, OP_Integer, 0, target);
|
|
}else{
|
|
/* This block populates the rNotFound register with either NULL
|
|
** or 0 (an integer value). If the data structure contains one
|
|
** or more NULLs, then set rNotFound to NULL. Otherwise, set it
|
|
** to 0. If register rMayHaveNull is already set to some value
|
|
** other than NULL, then the test has already been run and
|
|
** rNotFound is already populated.
|
|
*/
|
|
static const char nullRecord[] = { 0x02, 0x00 };
|
|
j3 = sqlite3VdbeAddOp1(v, OP_NotNull, rMayHaveNull);
|
|
sqlite3VdbeAddOp2(v, OP_Null, 0, rNotFound);
|
|
sqlite3VdbeAddOp4(v, OP_Blob, 2, rMayHaveNull, 0,
|
|
nullRecord, P4_STATIC);
|
|
j4 = sqlite3VdbeAddOp3(v, OP_Found, pExpr->iTable, 0, rMayHaveNull);
|
|
sqlite3VdbeAddOp2(v, OP_Integer, 0, rNotFound);
|
|
sqlite3VdbeJumpHere(v, j4);
|
|
sqlite3VdbeJumpHere(v, j3);
|
|
|
|
/* Copy the value of register rNotFound (which is either NULL or 0)
|
|
** into the target register. This will be the result of the
|
|
** expression.
|
|
*/
|
|
sqlite3VdbeAddOp2(v, OP_Copy, rNotFound, target);
|
|
}
|
|
}
|
|
sqlite3VdbeJumpHere(v, j2);
|
|
sqlite3VdbeJumpHere(v, j5);
|
|
VdbeComment((v, "end IN expr r%d", target));
|
|
break;
|
|
}
|
|
#endif
|
|
/*
|
|
** x BETWEEN y AND z
|
|
**
|
|
** This is equivalent to
|
|
**
|
|
** x>=y AND x<=z
|
|
**
|
|
** X is stored in pExpr->pLeft.
|
|
** Y is stored in pExpr->pList->a[0].pExpr.
|
|
** Z is stored in pExpr->pList->a[1].pExpr.
|
|
*/
|
|
case TK_BETWEEN: {
|
|
Expr *pLeft = pExpr->pLeft;
|
|
struct ExprList_item *pLItem = pExpr->pList->a;
|
|
Expr *pRight = pLItem->pExpr;
|
|
|
|
codeCompareOperands(pParse, pLeft, &r1, ®Free1,
|
|
pRight, &r2, ®Free2);
|
|
testcase( regFree1==0 );
|
|
testcase( regFree2==0 );
|
|
r3 = sqlite3GetTempReg(pParse);
|
|
r4 = sqlite3GetTempReg(pParse);
|
|
codeCompare(pParse, pLeft, pRight, OP_Ge,
|
|
r1, r2, r3, SQLITE_STOREP2);
|
|
pLItem++;
|
|
pRight = pLItem->pExpr;
|
|
sqlite3ReleaseTempReg(pParse, regFree2);
|
|
r2 = sqlite3ExprCodeTemp(pParse, pRight, ®Free2);
|
|
testcase( regFree2==0 );
|
|
codeCompare(pParse, pLeft, pRight, OP_Le, r1, r2, r4, SQLITE_STOREP2);
|
|
sqlite3VdbeAddOp3(v, OP_And, r3, r4, target);
|
|
sqlite3ReleaseTempReg(pParse, r3);
|
|
sqlite3ReleaseTempReg(pParse, r4);
|
|
break;
|
|
}
|
|
case TK_UPLUS: {
|
|
inReg = sqlite3ExprCodeTarget(pParse, pExpr->pLeft, target);
|
|
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 pExpr->pRight. The Y is also optional. If there is no
|
|
** ELSE clause and no other term matches, then the result of the
|
|
** exprssion 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 cacheX; /* Cached expression X */
|
|
Expr *pX; /* The X expression */
|
|
Expr *pTest; /* X==Ei (form A) or just Ei (form B) */
|
|
|
|
assert(pExpr->pList);
|
|
assert((pExpr->pList->nExpr % 2) == 0);
|
|
assert(pExpr->pList->nExpr > 0);
|
|
pEList = pExpr->pList;
|
|
aListelem = pEList->a;
|
|
nExpr = pEList->nExpr;
|
|
endLabel = sqlite3VdbeMakeLabel(v);
|
|
if( (pX = pExpr->pLeft)!=0 ){
|
|
cacheX = *pX;
|
|
testcase( pX->op==TK_COLUMN || pX->op==TK_REGISTER );
|
|
cacheX.iTable = sqlite3ExprCodeTemp(pParse, pX, ®Free1);
|
|
testcase( regFree1==0 );
|
|
cacheX.op = TK_REGISTER;
|
|
opCompare.op = TK_EQ;
|
|
opCompare.pLeft = &cacheX;
|
|
pTest = &opCompare;
|
|
}
|
|
pParse->disableColCache++;
|
|
for(i=0; i<nExpr; i=i+2){
|
|
if( pX ){
|
|
opCompare.pRight = aListelem[i].pExpr;
|
|
}else{
|
|
pTest = aListelem[i].pExpr;
|
|
}
|
|
nextCase = sqlite3VdbeMakeLabel(v);
|
|
testcase( pTest->op==TK_COLUMN || pTest->op==TK_REGISTER );
|
|
sqlite3ExprIfFalse(pParse, pTest, nextCase, SQLITE_JUMPIFNULL);
|
|
testcase( aListelem[i+1].pExpr->op==TK_COLUMN );
|
|
testcase( aListelem[i+1].pExpr->op==TK_REGISTER );
|
|
sqlite3ExprCode(pParse, aListelem[i+1].pExpr, target);
|
|
sqlite3VdbeAddOp2(v, OP_Goto, 0, endLabel);
|
|
sqlite3VdbeResolveLabel(v, nextCase);
|
|
}
|
|
if( pExpr->pRight ){
|
|
sqlite3ExprCode(pParse, pExpr->pRight, target);
|
|
}else{
|
|
sqlite3VdbeAddOp2(v, OP_Null, 0, target);
|
|
}
|
|
sqlite3VdbeResolveLabel(v, endLabel);
|
|
assert( pParse->disableColCache>0 );
|
|
pParse->disableColCache--;
|
|
break;
|
|
}
|
|
#ifndef SQLITE_OMIT_TRIGGER
|
|
case TK_RAISE: {
|
|
if( !pParse->trigStack ){
|
|
sqlite3ErrorMsg(pParse,
|
|
"RAISE() may only be used within a trigger-program");
|
|
return 0;
|
|
}
|
|
if( pExpr->iColumn!=OE_Ignore ){
|
|
assert( pExpr->iColumn==OE_Rollback ||
|
|
pExpr->iColumn == OE_Abort ||
|
|
pExpr->iColumn == OE_Fail );
|
|
sqlite3DequoteExpr(pParse->db, pExpr);
|
|
sqlite3VdbeAddOp4(v, OP_Halt, SQLITE_CONSTRAINT, pExpr->iColumn, 0,
|
|
(char*)pExpr->token.z, pExpr->token.n);
|
|
} else {
|
|
assert( pExpr->iColumn == OE_Ignore );
|
|
sqlite3VdbeAddOp2(v, OP_ContextPop, 0, 0);
|
|
sqlite3VdbeAddOp2(v, OP_Goto, 0, pParse->trigStack->ignoreJump);
|
|
VdbeComment((v, "raise(IGNORE)"));
|
|
}
|
|
break;
|
|
}
|
|
#endif
|
|
}
|
|
sqlite3ReleaseTempReg(pParse, regFree1);
|
|
sqlite3ReleaseTempReg(pParse, regFree2);
|
|
return inReg;
|
|
}
|
|
|
|
/*
|
|
** 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.
|
|
*/
|
|
int sqlite3ExprCodeTemp(Parse *pParse, Expr *pExpr, int *pReg){
|
|
int r1 = sqlite3GetTempReg(pParse);
|
|
int 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.
|
|
*/
|
|
int sqlite3ExprCode(Parse *pParse, Expr *pExpr, int target){
|
|
int inReg;
|
|
|
|
assert( target>0 && target<=pParse->nMem );
|
|
inReg = sqlite3ExprCodeTarget(pParse, pExpr, target);
|
|
assert( pParse->pVdbe || pParse->db->mallocFailed );
|
|
if( inReg!=target && pParse->pVdbe ){
|
|
sqlite3VdbeAddOp2(pParse->pVdbe, OP_SCopy, inReg, target);
|
|
}
|
|
return target;
|
|
}
|
|
|
|
/*
|
|
** Generate code that evalutes the given expression and puts the result
|
|
** in register target.
|
|
**
|
|
** Also make a copy of the expression results into another "cache" register
|
|
** and modify the expression so that the next time it is evaluated,
|
|
** the result is a copy of the cache register.
|
|
**
|
|
** This routine is used for expressions that are used multiple
|
|
** times. They are evaluated once and the results of the expression
|
|
** are reused.
|
|
*/
|
|
int sqlite3ExprCodeAndCache(Parse *pParse, Expr *pExpr, int target){
|
|
Vdbe *v = pParse->pVdbe;
|
|
int inReg;
|
|
inReg = sqlite3ExprCode(pParse, pExpr, target);
|
|
assert( target>0 );
|
|
if( pExpr->op!=TK_REGISTER ){
|
|
int iMem;
|
|
iMem = ++pParse->nMem;
|
|
sqlite3VdbeAddOp2(v, OP_Copy, inReg, iMem);
|
|
pExpr->iTable = iMem;
|
|
pExpr->op = TK_REGISTER;
|
|
}
|
|
return inReg;
|
|
}
|
|
|
|
/*
|
|
** Return TRUE if pExpr is an constant expression that is appropriate
|
|
** for factoring out of a loop. Appropriate expressions are:
|
|
**
|
|
** * Any expression that evaluates to two or more opcodes.
|
|
**
|
|
** * Any OP_Integer, OP_Real, OP_String, OP_Blob, OP_Null,
|
|
** or OP_Variable that does not need to be placed in a
|
|
** specific register.
|
|
**
|
|
** There is no point in factoring out single-instruction constant
|
|
** expressions that need to be placed in a particular register.
|
|
** We could factor them out, but then we would end up adding an
|
|
** OP_SCopy instruction to move the value into the correct register
|
|
** later. We might as well just use the original instruction and
|
|
** avoid the OP_SCopy.
|
|
*/
|
|
static int isAppropriateForFactoring(Expr *p){
|
|
if( !sqlite3ExprIsConstantNotJoin(p) ){
|
|
return 0; /* Only constant expressions are appropriate for factoring */
|
|
}
|
|
if( (p->flags & EP_FixedDest)==0 ){
|
|
return 1; /* Any constant without a fixed destination is appropriate */
|
|
}
|
|
while( p->op==TK_UPLUS ) p = p->pLeft;
|
|
switch( p->op ){
|
|
#ifndef SQLITE_OMIT_BLOB_LITERAL
|
|
case TK_BLOB:
|
|
#endif
|
|
case TK_VARIABLE:
|
|
case TK_INTEGER:
|
|
case TK_FLOAT:
|
|
case TK_NULL:
|
|
case TK_STRING: {
|
|
testcase( p->op==TK_BLOB );
|
|
testcase( p->op==TK_VARIABLE );
|
|
testcase( p->op==TK_INTEGER );
|
|
testcase( p->op==TK_FLOAT );
|
|
testcase( p->op==TK_NULL );
|
|
testcase( p->op==TK_STRING );
|
|
/* Single-instruction constants with a fixed destination are
|
|
** better done in-line. If we factor them, they will just end
|
|
** up generating an OP_SCopy to move the value to the destination
|
|
** register. */
|
|
return 0;
|
|
}
|
|
case TK_UMINUS: {
|
|
if( p->pLeft->op==TK_FLOAT || p->pLeft->op==TK_INTEGER ){
|
|
return 0;
|
|
}
|
|
break;
|
|
}
|
|
default: {
|
|
break;
|
|
}
|
|
}
|
|
return 1;
|
|
}
|
|
|
|
/*
|
|
** If pExpr is a constant expression that is appropriate for
|
|
** factoring out of a loop, then evaluate the expression
|
|
** into a register and convert the expression into a TK_REGISTER
|
|
** expression.
|
|
*/
|
|
static int evalConstExpr(Walker *pWalker, Expr *pExpr){
|
|
Parse *pParse = pWalker->pParse;
|
|
switch( pExpr->op ){
|
|
case TK_REGISTER: {
|
|
return 1;
|
|
}
|
|
case TK_FUNCTION:
|
|
case TK_AGG_FUNCTION:
|
|
case TK_CONST_FUNC: {
|
|
/* The arguments to a function have a fixed destination.
|
|
** Mark them this way to avoid generated unneeded OP_SCopy
|
|
** instructions.
|
|
*/
|
|
ExprList *pList = pExpr->pList;
|
|
if( pList ){
|
|
int i = pList->nExpr;
|
|
struct ExprList_item *pItem = pList->a;
|
|
for(; i>0; i--, pItem++){
|
|
if( pItem->pExpr ) pItem->pExpr->flags |= EP_FixedDest;
|
|
}
|
|
}
|
|
break;
|
|
}
|
|
}
|
|
if( isAppropriateForFactoring(pExpr) ){
|
|
int r1 = ++pParse->nMem;
|
|
int r2;
|
|
r2 = sqlite3ExprCodeTarget(pParse, pExpr, r1);
|
|
if( r1!=r2 ) sqlite3ReleaseTempReg(pParse, r1);
|
|
pExpr->op = TK_REGISTER;
|
|
pExpr->iTable = r2;
|
|
return WRC_Prune;
|
|
}
|
|
return WRC_Continue;
|
|
}
|
|
|
|
/*
|
|
** Preevaluate constant subexpressions within pExpr and store the
|
|
** results in registers. Modify pExpr so that the constant subexpresions
|
|
** are TK_REGISTER opcodes that refer to the precomputed values.
|
|
*/
|
|
void sqlite3ExprCodeConstants(Parse *pParse, Expr *pExpr){
|
|
Walker w;
|
|
w.xExprCallback = evalConstExpr;
|
|
w.xSelectCallback = 0;
|
|
w.pParse = pParse;
|
|
sqlite3WalkExpr(&w, pExpr);
|
|
}
|
|
|
|
|
|
/*
|
|
** 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.
|
|
*/
|
|
int sqlite3ExprCodeExprList(
|
|
Parse *pParse, /* Parsing context */
|
|
ExprList *pList, /* The expression list to be coded */
|
|
int target, /* Where to write results */
|
|
int doHardCopy /* Call sqlite3ExprHardCopy on each element if true */
|
|
){
|
|
struct ExprList_item *pItem;
|
|
int i, n;
|
|
assert( pList!=0 );
|
|
assert( target>0 );
|
|
n = pList->nExpr;
|
|
for(pItem=pList->a, i=0; i<n; i++, pItem++){
|
|
sqlite3ExprCode(pParse, pItem->pExpr, target+i);
|
|
if( doHardCopy ) sqlite3ExprHardCopy(pParse, target, n);
|
|
}
|
|
return n;
|
|
}
|
|
|
|
/*
|
|
** 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( v==0 || pExpr==0 ) return;
|
|
op = pExpr->op;
|
|
switch( op ){
|
|
case TK_AND: {
|
|
int d2 = sqlite3VdbeMakeLabel(v);
|
|
testcase( jumpIfNull==0 );
|
|
testcase( pParse->disableColCache==0 );
|
|
sqlite3ExprIfFalse(pParse, pExpr->pLeft, d2,jumpIfNull^SQLITE_JUMPIFNULL);
|
|
pParse->disableColCache++;
|
|
sqlite3ExprIfTrue(pParse, pExpr->pRight, dest, jumpIfNull);
|
|
assert( pParse->disableColCache>0 );
|
|
pParse->disableColCache--;
|
|
sqlite3VdbeResolveLabel(v, d2);
|
|
break;
|
|
}
|
|
case TK_OR: {
|
|
testcase( jumpIfNull==0 );
|
|
testcase( pParse->disableColCache==0 );
|
|
sqlite3ExprIfTrue(pParse, pExpr->pLeft, dest, jumpIfNull);
|
|
pParse->disableColCache++;
|
|
sqlite3ExprIfTrue(pParse, pExpr->pRight, dest, jumpIfNull);
|
|
assert( pParse->disableColCache>0 );
|
|
pParse->disableColCache--;
|
|
break;
|
|
}
|
|
case TK_NOT: {
|
|
testcase( jumpIfNull==0 );
|
|
sqlite3ExprIfFalse(pParse, pExpr->pLeft, dest, jumpIfNull);
|
|
break;
|
|
}
|
|
case TK_LT:
|
|
case TK_LE:
|
|
case TK_GT:
|
|
case TK_GE:
|
|
case TK_NE:
|
|
case TK_EQ: {
|
|
assert( TK_LT==OP_Lt );
|
|
assert( TK_LE==OP_Le );
|
|
assert( TK_GT==OP_Gt );
|
|
assert( TK_GE==OP_Ge );
|
|
assert( TK_EQ==OP_Eq );
|
|
assert( TK_NE==OP_Ne );
|
|
testcase( op==TK_LT );
|
|
testcase( op==TK_LE );
|
|
testcase( op==TK_GT );
|
|
testcase( op==TK_GE );
|
|
testcase( op==TK_EQ );
|
|
testcase( op==TK_NE );
|
|
testcase( jumpIfNull==0 );
|
|
codeCompareOperands(pParse, pExpr->pLeft, &r1, ®Free1,
|
|
pExpr->pRight, &r2, ®Free2);
|
|
codeCompare(pParse, pExpr->pLeft, pExpr->pRight, op,
|
|
r1, r2, dest, jumpIfNull);
|
|
testcase( regFree1==0 );
|
|
testcase( regFree2==0 );
|
|
break;
|
|
}
|
|
case TK_ISNULL:
|
|
case TK_NOTNULL: {
|
|
assert( TK_ISNULL==OP_IsNull );
|
|
assert( TK_NOTNULL==OP_NotNull );
|
|
testcase( op==TK_ISNULL );
|
|
testcase( op==TK_NOTNULL );
|
|
r1 = sqlite3ExprCodeTemp(pParse, pExpr->pLeft, ®Free1);
|
|
sqlite3VdbeAddOp2(v, op, r1, dest);
|
|
testcase( regFree1==0 );
|
|
break;
|
|
}
|
|
case TK_BETWEEN: {
|
|
/* x BETWEEN y AND z
|
|
**
|
|
** Is equivalent to
|
|
**
|
|
** x>=y AND x<=z
|
|
**
|
|
** Code it as such, taking care to do the common subexpression
|
|
** elementation of x.
|
|
*/
|
|
Expr exprAnd;
|
|
Expr compLeft;
|
|
Expr compRight;
|
|
Expr exprX;
|
|
|
|
exprX = *pExpr->pLeft;
|
|
exprAnd.op = TK_AND;
|
|
exprAnd.pLeft = &compLeft;
|
|
exprAnd.pRight = &compRight;
|
|
compLeft.op = TK_GE;
|
|
compLeft.pLeft = &exprX;
|
|
compLeft.pRight = pExpr->pList->a[0].pExpr;
|
|
compRight.op = TK_LE;
|
|
compRight.pLeft = &exprX;
|
|
compRight.pRight = pExpr->pList->a[1].pExpr;
|
|
exprX.iTable = sqlite3ExprCodeTemp(pParse, &exprX, ®Free1);
|
|
testcase( regFree1==0 );
|
|
exprX.op = TK_REGISTER;
|
|
testcase( jumpIfNull==0 );
|
|
sqlite3ExprIfTrue(pParse, &exprAnd, dest, jumpIfNull);
|
|
break;
|
|
}
|
|
default: {
|
|
r1 = sqlite3ExprCodeTemp(pParse, pExpr, ®Free1);
|
|
sqlite3VdbeAddOp3(v, OP_If, r1, dest, jumpIfNull!=0);
|
|
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( v==0 || pExpr==0 ) return;
|
|
|
|
/* The value of pExpr->op and op are related as follows:
|
|
**
|
|
** pExpr->op op
|
|
** --------- ----------
|
|
** TK_ISNULL OP_NotNull
|
|
** TK_NOTNULL OP_IsNull
|
|
** TK_NE OP_Eq
|
|
** TK_EQ OP_Ne
|
|
** TK_GT OP_Le
|
|
** TK_LE OP_Gt
|
|
** TK_GE OP_Lt
|
|
** TK_LT OP_Ge
|
|
**
|
|
** For other values of pExpr->op, op is undefined and unused.
|
|
** The value of TK_ and OP_ constants are arranged such that we
|
|
** can compute the mapping above using the following expression.
|
|
** Assert()s verify that the computation is correct.
|
|
*/
|
|
op = ((pExpr->op+(TK_ISNULL&1))^1)-(TK_ISNULL&1);
|
|
|
|
/* Verify correct alignment of TK_ and OP_ constants
|
|
*/
|
|
assert( pExpr->op!=TK_ISNULL || op==OP_NotNull );
|
|
assert( pExpr->op!=TK_NOTNULL || op==OP_IsNull );
|
|
assert( pExpr->op!=TK_NE || op==OP_Eq );
|
|
assert( pExpr->op!=TK_EQ || op==OP_Ne );
|
|
assert( pExpr->op!=TK_LT || op==OP_Ge );
|
|
assert( pExpr->op!=TK_LE || op==OP_Gt );
|
|
assert( pExpr->op!=TK_GT || op==OP_Le );
|
|
assert( pExpr->op!=TK_GE || op==OP_Lt );
|
|
|
|
switch( pExpr->op ){
|
|
case TK_AND: {
|
|
testcase( jumpIfNull==0 );
|
|
testcase( pParse->disableColCache==0 );
|
|
sqlite3ExprIfFalse(pParse, pExpr->pLeft, dest, jumpIfNull);
|
|
pParse->disableColCache++;
|
|
sqlite3ExprIfFalse(pParse, pExpr->pRight, dest, jumpIfNull);
|
|
assert( pParse->disableColCache>0 );
|
|
pParse->disableColCache--;
|
|
break;
|
|
}
|
|
case TK_OR: {
|
|
int d2 = sqlite3VdbeMakeLabel(v);
|
|
testcase( jumpIfNull==0 );
|
|
testcase( pParse->disableColCache==0 );
|
|
sqlite3ExprIfTrue(pParse, pExpr->pLeft, d2, jumpIfNull^SQLITE_JUMPIFNULL);
|
|
pParse->disableColCache++;
|
|
sqlite3ExprIfFalse(pParse, pExpr->pRight, dest, jumpIfNull);
|
|
assert( pParse->disableColCache>0 );
|
|
pParse->disableColCache--;
|
|
sqlite3VdbeResolveLabel(v, d2);
|
|
break;
|
|
}
|
|
case TK_NOT: {
|
|
sqlite3ExprIfTrue(pParse, pExpr->pLeft, dest, jumpIfNull);
|
|
break;
|
|
}
|
|
case TK_LT:
|
|
case TK_LE:
|
|
case TK_GT:
|
|
case TK_GE:
|
|
case TK_NE:
|
|
case TK_EQ: {
|
|
testcase( op==TK_LT );
|
|
testcase( op==TK_LE );
|
|
testcase( op==TK_GT );
|
|
testcase( op==TK_GE );
|
|
testcase( op==TK_EQ );
|
|
testcase( op==TK_NE );
|
|
testcase( jumpIfNull==0 );
|
|
codeCompareOperands(pParse, pExpr->pLeft, &r1, ®Free1,
|
|
pExpr->pRight, &r2, ®Free2);
|
|
codeCompare(pParse, pExpr->pLeft, pExpr->pRight, op,
|
|
r1, r2, dest, jumpIfNull);
|
|
testcase( regFree1==0 );
|
|
testcase( regFree2==0 );
|
|
break;
|
|
}
|
|
case TK_ISNULL:
|
|
case TK_NOTNULL: {
|
|
testcase( op==TK_ISNULL );
|
|
testcase( op==TK_NOTNULL );
|
|
r1 = sqlite3ExprCodeTemp(pParse, pExpr->pLeft, ®Free1);
|
|
sqlite3VdbeAddOp2(v, op, r1, dest);
|
|
testcase( regFree1==0 );
|
|
break;
|
|
}
|
|
case TK_BETWEEN: {
|
|
/* x BETWEEN y AND z
|
|
**
|
|
** Is equivalent to
|
|
**
|
|
** x>=y AND x<=z
|
|
**
|
|
** Code it as such, taking care to do the common subexpression
|
|
** elementation of x.
|
|
*/
|
|
Expr exprAnd;
|
|
Expr compLeft;
|
|
Expr compRight;
|
|
Expr exprX;
|
|
|
|
exprX = *pExpr->pLeft;
|
|
exprAnd.op = TK_AND;
|
|
exprAnd.pLeft = &compLeft;
|
|
exprAnd.pRight = &compRight;
|
|
compLeft.op = TK_GE;
|
|
compLeft.pLeft = &exprX;
|
|
compLeft.pRight = pExpr->pList->a[0].pExpr;
|
|
compRight.op = TK_LE;
|
|
compRight.pLeft = &exprX;
|
|
compRight.pRight = pExpr->pList->a[1].pExpr;
|
|
exprX.iTable = sqlite3ExprCodeTemp(pParse, &exprX, ®Free1);
|
|
testcase( regFree1==0 );
|
|
exprX.op = TK_REGISTER;
|
|
testcase( jumpIfNull==0 );
|
|
sqlite3ExprIfFalse(pParse, &exprAnd, dest, jumpIfNull);
|
|
break;
|
|
}
|
|
default: {
|
|
r1 = sqlite3ExprCodeTemp(pParse, pExpr, ®Free1);
|
|
sqlite3VdbeAddOp3(v, OP_IfNot, r1, dest, jumpIfNull!=0);
|
|
testcase( regFree1==0 );
|
|
testcase( jumpIfNull==0 );
|
|
break;
|
|
}
|
|
}
|
|
sqlite3ReleaseTempReg(pParse, regFree1);
|
|
sqlite3ReleaseTempReg(pParse, regFree2);
|
|
}
|
|
|
|
/*
|
|
** Do a deep comparison of two expression trees. Return TRUE (non-zero)
|
|
** if they are identical and return FALSE if they differ in any way.
|
|
**
|
|
** Sometimes this routine will return FALSE even if the two expressions
|
|
** really are equivalent. If we cannot prove that the expressions are
|
|
** identical, we return FALSE just to be safe. So if this routine
|
|
** returns false, then you do not really know for certain if the two
|
|
** expressions are the same. But if you get a TRUE 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 FALSE - that
|
|
** just might result in some slightly slower code. But returning
|
|
** an incorrect TRUE could lead to a malfunction.
|
|
*/
|
|
int sqlite3ExprCompare(Expr *pA, Expr *pB){
|
|
int i;
|
|
if( pA==0||pB==0 ){
|
|
return pB==pA;
|
|
}
|
|
if( pA->op!=pB->op ) return 0;
|
|
if( (pA->flags & EP_Distinct)!=(pB->flags & EP_Distinct) ) return 0;
|
|
if( !sqlite3ExprCompare(pA->pLeft, pB->pLeft) ) return 0;
|
|
if( !sqlite3ExprCompare(pA->pRight, pB->pRight) ) return 0;
|
|
if( pA->pList ){
|
|
if( pB->pList==0 ) return 0;
|
|
if( pA->pList->nExpr!=pB->pList->nExpr ) return 0;
|
|
for(i=0; i<pA->pList->nExpr; i++){
|
|
if( !sqlite3ExprCompare(pA->pList->a[i].pExpr, pB->pList->a[i].pExpr) ){
|
|
return 0;
|
|
}
|
|
}
|
|
}else if( pB->pList ){
|
|
return 0;
|
|
}
|
|
if( pA->pSelect || pB->pSelect ) return 0;
|
|
if( pA->iTable!=pB->iTable || pA->iColumn!=pB->iColumn ) return 0;
|
|
if( pA->op!=TK_COLUMN && pA->token.z ){
|
|
if( pB->token.z==0 ) return 0;
|
|
if( pB->token.n!=pA->token.n ) return 0;
|
|
if( sqlite3StrNICmp((char*)pA->token.z,(char*)pB->token.z,pB->token.n)!=0 ){
|
|
return 0;
|
|
}
|
|
}
|
|
return 1;
|
|
}
|
|
|
|
|
|
/*
|
|
** 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]),
|
|
3,
|
|
&pInfo->nColumn,
|
|
&pInfo->nColumnAlloc,
|
|
&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]),
|
|
3,
|
|
&pInfo->nFunc,
|
|
&pInfo->nFuncAlloc,
|
|
&i
|
|
);
|
|
return i;
|
|
}
|
|
|
|
/*
|
|
** This is the xExprCallback for a tree walker. It is used to
|
|
** implement sqlite3ExprAnalyzeAggregates(). See sqlite3ExprAnalyzeAggregates
|
|
** for additional information.
|
|
*/
|
|
static int analyzeAggregate(Walker *pWalker, Expr *pExpr){
|
|
int i;
|
|
NameContext *pNC = pWalker->u.pNC;
|
|
Parse *pParse = pNC->pParse;
|
|
SrcList *pSrcList = pNC->pSrcList;
|
|
AggInfo *pAggInfo = pNC->pAggInfo;
|
|
|
|
switch( pExpr->op ){
|
|
case TK_AGG_COLUMN:
|
|
case TK_COLUMN: {
|
|
/* Check to see if the column is in one of the tables in the FROM
|
|
** clause of the aggregate query */
|
|
if( pSrcList ){
|
|
struct SrcList_item *pItem = pSrcList->a;
|
|
for(i=0; i<pSrcList->nSrc; i++, pItem++){
|
|
struct AggInfo_col *pCol;
|
|
if( pExpr->iTable==pItem->iCursor ){
|
|
/* If we reach this point, it means that pExpr refers to a table
|
|
** that is in the FROM clause of the aggregate query.
|
|
**
|
|
** Make an entry for the column in pAggInfo->aCol[] if there
|
|
** is not an entry there already.
|
|
*/
|
|
int k;
|
|
pCol = pAggInfo->aCol;
|
|
for(k=0; k<pAggInfo->nColumn; k++, pCol++){
|
|
if( pCol->iTable==pExpr->iTable &&
|
|
pCol->iColumn==pExpr->iColumn ){
|
|
break;
|
|
}
|
|
}
|
|
if( (k>=pAggInfo->nColumn)
|
|
&& (k = addAggInfoColumn(pParse->db, pAggInfo))>=0
|
|
){
|
|
pCol = &pAggInfo->aCol[k];
|
|
pCol->pTab = pExpr->pTab;
|
|
pCol->iTable = pExpr->iTable;
|
|
pCol->iColumn = pExpr->iColumn;
|
|
pCol->iMem = ++pParse->nMem;
|
|
pCol->iSorterColumn = -1;
|
|
pCol->pExpr = pExpr;
|
|
if( pAggInfo->pGroupBy ){
|
|
int j, n;
|
|
ExprList *pGB = pAggInfo->pGroupBy;
|
|
struct ExprList_item *pTerm = pGB->a;
|
|
n = pGB->nExpr;
|
|
for(j=0; j<n; j++, pTerm++){
|
|
Expr *pE = pTerm->pExpr;
|
|
if( pE->op==TK_COLUMN && pE->iTable==pExpr->iTable &&
|
|
pE->iColumn==pExpr->iColumn ){
|
|
pCol->iSorterColumn = j;
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
if( pCol->iSorterColumn<0 ){
|
|
pCol->iSorterColumn = pAggInfo->nSortingColumn++;
|
|
}
|
|
}
|
|
/* There is now an entry for pExpr in pAggInfo->aCol[] (either
|
|
** because it was there before or because we just created it).
|
|
** Convert the pExpr to be a TK_AGG_COLUMN referring to that
|
|
** pAggInfo->aCol[] entry.
|
|
*/
|
|
pExpr->pAggInfo = pAggInfo;
|
|
pExpr->op = TK_AGG_COLUMN;
|
|
pExpr->iAgg = k;
|
|
break;
|
|
} /* endif pExpr->iTable==pItem->iCursor */
|
|
} /* end loop over pSrcList */
|
|
}
|
|
return WRC_Prune;
|
|
}
|
|
case TK_AGG_FUNCTION: {
|
|
/* The pNC->nDepth==0 test causes aggregate functions in subqueries
|
|
** to be ignored */
|
|
if( pNC->nDepth==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( sqlite3ExprCompare(pItem->pExpr, pExpr) ){
|
|
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 ){
|
|
pItem = &pAggInfo->aFunc[i];
|
|
pItem->pExpr = pExpr;
|
|
pItem->iMem = ++pParse->nMem;
|
|
pItem->pFunc = sqlite3FindFunction(pParse->db,
|
|
(char*)pExpr->token.z, pExpr->token.n,
|
|
pExpr->pList ? pExpr->pList->nExpr : 0, enc, 0);
|
|
if( pExpr->flags & EP_Distinct ){
|
|
pItem->iDistinct = pParse->nTab++;
|
|
}else{
|
|
pItem->iDistinct = -1;
|
|
}
|
|
}
|
|
}
|
|
/* Make pExpr point to the appropriate pAggInfo->aFunc[] entry
|
|
*/
|
|
pExpr->iAgg = i;
|
|
pExpr->pAggInfo = pAggInfo;
|
|
return WRC_Prune;
|
|
}
|
|
}
|
|
}
|
|
return WRC_Continue;
|
|
}
|
|
static int analyzeAggregatesInSelect(Walker *pWalker, Select *pSelect){
|
|
NameContext *pNC = pWalker->u.pNC;
|
|
if( pNC->nDepth==0 ){
|
|
pNC->nDepth++;
|
|
sqlite3WalkSelect(pWalker, pSelect);
|
|
pNC->nDepth--;
|
|
return WRC_Prune;
|
|
}else{
|
|
return WRC_Continue;
|
|
}
|
|
}
|
|
|
|
/*
|
|
** Analyze the given expression looking for aggregate functions and
|
|
** for variables that need to be added to the pParse->aAgg[] array.
|
|
** Make additional entries to the pParse->aAgg[] array 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 = analyzeAggregatesInSelect;
|
|
w.u.pNC = pNC;
|
|
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 or deallocate temporary use registers during code generation.
|
|
*/
|
|
int sqlite3GetTempReg(Parse *pParse){
|
|
if( pParse->nTempReg==0 ){
|
|
return ++pParse->nMem;
|
|
}
|
|
return pParse->aTempReg[--pParse->nTempReg];
|
|
}
|
|
void sqlite3ReleaseTempReg(Parse *pParse, int iReg){
|
|
if( iReg && pParse->nTempReg<ArraySize(pParse->aTempReg) ){
|
|
sqlite3ExprWritableRegister(pParse, iReg, iReg);
|
|
pParse->aTempReg[pParse->nTempReg++] = iReg;
|
|
}
|
|
}
|
|
|
|
/*
|
|
** Allocate or deallocate a block of nReg consecutive registers
|
|
*/
|
|
int sqlite3GetTempRange(Parse *pParse, int nReg){
|
|
int i, n;
|
|
i = pParse->iRangeReg;
|
|
n = pParse->nRangeReg;
|
|
if( nReg<=n && !usedAsColumnCache(pParse, i, i+n-1) ){
|
|
pParse->iRangeReg += nReg;
|
|
pParse->nRangeReg -= nReg;
|
|
}else{
|
|
i = pParse->nMem+1;
|
|
pParse->nMem += nReg;
|
|
}
|
|
return i;
|
|
}
|
|
void sqlite3ReleaseTempRange(Parse *pParse, int iReg, int nReg){
|
|
if( nReg>pParse->nRangeReg ){
|
|
pParse->nRangeReg = nReg;
|
|
pParse->iRangeReg = iReg;
|
|
}
|
|
}
|