#include "sqliteInt.h"
#define BMS (sizeof(Bitmask)*8)
#if defined(SQLITE_TEST) || defined(SQLITE_DEBUG)
int sqlite3_where_trace = 0;
# define WHERETRACE(X) if(sqlite3_where_trace) sqlite3DebugPrintf X
#else
# define WHERETRACE(X)
#endif
typedef struct WhereClause WhereClause;
typedef struct ExprMaskSet ExprMaskSet;
typedef struct WhereTerm WhereTerm;
struct WhereTerm {
Expr *pExpr;
i16 iParent;
i16 leftCursor;
i16 leftColumn;
u16 eOperator;
u8 flags;
u8 nChild;
WhereClause *pWC;
Bitmask prereqRight;
Bitmask prereqAll;
};
#define TERM_DYNAMIC 0x01
#define TERM_VIRTUAL 0x02
#define TERM_CODED 0x04
#define TERM_COPIED 0x08
#define TERM_OR_OK 0x10
struct WhereClause {
Parse *pParse;
ExprMaskSet *pMaskSet;
int nTerm;
int nSlot;
WhereTerm *a;
WhereTerm aStatic[10];
};
struct ExprMaskSet {
int n;
int ix[sizeof(Bitmask)*8];
};
#define WO_IN 1
#define WO_EQ 2
#define WO_LT (WO_EQ<<(TK_LT-TK_EQ))
#define WO_LE (WO_EQ<<(TK_LE-TK_EQ))
#define WO_GT (WO_EQ<<(TK_GT-TK_EQ))
#define WO_GE (WO_EQ<<(TK_GE-TK_EQ))
#define WO_MATCH 64
#define WO_ISNULL 128
#define WHERE_ROWID_EQ 0x000100
#define WHERE_ROWID_RANGE 0x000200
#define WHERE_COLUMN_EQ 0x001000
#define WHERE_COLUMN_RANGE 0x002000
#define WHERE_COLUMN_IN 0x004000
#define WHERE_TOP_LIMIT 0x010000
#define WHERE_BTM_LIMIT 0x020000
#define WHERE_IDX_ONLY 0x080000
#define WHERE_ORDERBY 0x100000
#define WHERE_REVERSE 0x200000
#define WHERE_UNIQUE 0x400000
#define WHERE_VIRTUALTABLE 0x800000
static void whereClauseInit(
WhereClause *pWC,
Parse *pParse,
ExprMaskSet *pMaskSet
){
pWC->pParse = pParse;
pWC->pMaskSet = pMaskSet;
pWC->nTerm = 0;
pWC->nSlot = ArraySize(pWC->aStatic);
pWC->a = pWC->aStatic;
}
static void whereClauseClear(WhereClause *pWC){
int i;
WhereTerm *a;
for(i=pWC->nTerm-1, a=pWC->a; i>=0; i--, a++){
if( a->flags & TERM_DYNAMIC ){
sqlite3ExprDelete(a->pExpr);
}
}
if( pWC->a!=pWC->aStatic ){
sqliteFree(pWC->a);
}
}
static int whereClauseInsert(WhereClause *pWC, Expr *p, int flags){
WhereTerm *pTerm;
int idx;
if( pWC->nTerm>=pWC->nSlot ){
WhereTerm *pOld = pWC->a;
pWC->a = sqliteMalloc( sizeof(pWC->a[0])*pWC->nSlot*2 );
if( pWC->a==0 ){
if( flags & TERM_DYNAMIC ){
sqlite3ExprDelete(p);
}
return 0;
}
memcpy(pWC->a, pOld, sizeof(pWC->a[0])*pWC->nTerm);
if( pOld!=pWC->aStatic ){
sqliteFree(pOld);
}
pWC->nSlot *= 2;
}
pTerm = &pWC->a[idx = pWC->nTerm];
pWC->nTerm++;
pTerm->pExpr = p;
pTerm->flags = flags;
pTerm->pWC = pWC;
pTerm->iParent = -1;
return idx;
}
static void whereSplit(WhereClause *pWC, Expr *pExpr, int op){
if( pExpr==0 ) return;
if( pExpr->op!=op ){
whereClauseInsert(pWC, pExpr, 0);
}else{
whereSplit(pWC, pExpr->pLeft, op);
whereSplit(pWC, pExpr->pRight, op);
}
}
#define initMaskSet(P) memset(P, 0, sizeof(*P))
static Bitmask getMask(ExprMaskSet *pMaskSet, int iCursor){
int i;
for(i=0; i<pMaskSet->n; i++){
if( pMaskSet->ix[i]==iCursor ){
return ((Bitmask)1)<<i;
}
}
return 0;
}
static void createMask(ExprMaskSet *pMaskSet, int iCursor){
assert( pMaskSet->n < ArraySize(pMaskSet->ix) );
pMaskSet->ix[pMaskSet->n++] = iCursor;
}
static Bitmask exprListTableUsage(ExprMaskSet*, ExprList*);
static Bitmask exprSelectTableUsage(ExprMaskSet*, Select*);
static Bitmask exprTableUsage(ExprMaskSet *pMaskSet, Expr *p){
Bitmask mask = 0;
if( p==0 ) return 0;
if( p->op==TK_COLUMN ){
mask = getMask(pMaskSet, p->iTable);
return mask;
}
mask = exprTableUsage(pMaskSet, p->pRight);
mask |= exprTableUsage(pMaskSet, p->pLeft);
mask |= exprListTableUsage(pMaskSet, p->pList);
mask |= exprSelectTableUsage(pMaskSet, p->pSelect);
return mask;
}
static Bitmask exprListTableUsage(ExprMaskSet *pMaskSet, ExprList *pList){
int i;
Bitmask mask = 0;
if( pList ){
for(i=0; i<pList->nExpr; i++){
mask |= exprTableUsage(pMaskSet, pList->a[i].pExpr);
}
}
return mask;
}
static Bitmask exprSelectTableUsage(ExprMaskSet *pMaskSet, Select *pS){
Bitmask mask;
if( pS==0 ){
mask = 0;
}else{
mask = exprListTableUsage(pMaskSet, pS->pEList);
mask |= exprListTableUsage(pMaskSet, pS->pGroupBy);
mask |= exprListTableUsage(pMaskSet, pS->pOrderBy);
mask |= exprTableUsage(pMaskSet, pS->pWhere);
mask |= exprTableUsage(pMaskSet, pS->pHaving);
}
return mask;
}
static int allowedOp(int op){
assert( TK_GT>TK_EQ && TK_GT<TK_GE );
assert( TK_LT>TK_EQ && TK_LT<TK_GE );
assert( TK_LE>TK_EQ && TK_LE<TK_GE );
assert( TK_GE==TK_EQ+4 );
return op==TK_IN || (op>=TK_EQ && op<=TK_GE) || op==TK_ISNULL;
}
#define SWAP(TYPE,A,B) {TYPE t=A; A=B; B=t;}
static void exprCommute(Expr *pExpr){
assert( allowedOp(pExpr->op) && pExpr->op!=TK_IN );
SWAP(CollSeq*,pExpr->pRight->pColl,pExpr->pLeft->pColl);
SWAP(Expr*,pExpr->pRight,pExpr->pLeft);
if( pExpr->op>=TK_GT ){
assert( TK_LT==TK_GT+2 );
assert( TK_GE==TK_LE+2 );
assert( TK_GT>TK_EQ );
assert( TK_GT<TK_LE );
assert( pExpr->op>=TK_GT && pExpr->op<=TK_GE );
pExpr->op = ((pExpr->op-TK_GT)^2)+TK_GT;
}
}
static int operatorMask(int op){
int c;
assert( allowedOp(op) );
if( op==TK_IN ){
c = WO_IN;
}else if( op==TK_ISNULL ){
c = WO_ISNULL;
}else{
c = WO_EQ<<(op-TK_EQ);
}
assert( op!=TK_ISNULL || c==WO_ISNULL );
assert( op!=TK_IN || c==WO_IN );
assert( op!=TK_EQ || c==WO_EQ );
assert( op!=TK_LT || c==WO_LT );
assert( op!=TK_LE || c==WO_LE );
assert( op!=TK_GT || c==WO_GT );
assert( op!=TK_GE || c==WO_GE );
return c;
}
static WhereTerm *findTerm(
WhereClause *pWC,
int iCur,
int iColumn,
Bitmask notReady,
u16 op,
Index *pIdx
){
WhereTerm *pTerm;
int k;
for(pTerm=pWC->a, k=pWC->nTerm; k; k--, pTerm++){
if( pTerm->leftCursor==iCur
&& (pTerm->prereqRight & notReady)==0
&& pTerm->leftColumn==iColumn
&& (pTerm->eOperator & op)!=0
){
if( iCur>=0 && pIdx && pTerm->eOperator!=WO_ISNULL ){
Expr *pX = pTerm->pExpr;
CollSeq *pColl;
char idxaff;
int j;
Parse *pParse = pWC->pParse;
idxaff = pIdx->pTable->aCol[iColumn].affinity;
if( !sqlite3IndexAffinityOk(pX, idxaff) ) continue;
pColl = sqlite3ExprCollSeq(pParse, pX->pLeft);
if( !pColl ){
if( pX->pRight ){
pColl = sqlite3ExprCollSeq(pParse, pX->pRight);
}
if( !pColl ){
pColl = pParse->db->pDfltColl;
}
}
for(j=0; j<pIdx->nColumn && pIdx->aiColumn[j]!=iColumn; j++){}
assert( j<pIdx->nColumn );
if( sqlite3StrICmp(pColl->zName, pIdx->azColl[j]) ) continue;
}
return pTerm;
}
}
return 0;
}
static void exprAnalyze(SrcList*, WhereClause*, int);
static void exprAnalyzeAll(
SrcList *pTabList,
WhereClause *pWC
){
int i;
for(i=pWC->nTerm-1; i>=0; i--){
exprAnalyze(pTabList, pWC, i);
}
}
#ifndef SQLITE_OMIT_LIKE_OPTIMIZATION
static int isLikeOrGlob(
sqlite3 *db,
Expr *pExpr,
int *pnPattern,
int *pisComplete
){
const char *z;
Expr *pRight, *pLeft;
ExprList *pList;
int c, cnt;
int noCase;
char wc[3];
CollSeq *pColl;
if( !sqlite3IsLikeFunction(db, pExpr, &noCase, wc) ){
return 0;
}
pList = pExpr->pList;
pRight = pList->a[0].pExpr;
if( pRight->op!=TK_STRING ){
return 0;
}
pLeft = pList->a[1].pExpr;
if( pLeft->op!=TK_COLUMN ){
return 0;
}
pColl = pLeft->pColl;
if( pColl==0 ){
pColl = db->pDfltColl;
}
if( (pColl->type!=SQLITE_COLL_BINARY || noCase) &&
(pColl->type!=SQLITE_COLL_NOCASE || !noCase) ){
return 0;
}
sqlite3DequoteExpr(pRight);
z = (char *)pRight->token.z;
for(cnt=0; (c=z[cnt])!=0 && c!=wc[0] && c!=wc[1] && c!=wc[2]; cnt++){}
if( cnt==0 || 255==(u8)z[cnt] ){
return 0;
}
*pisComplete = z[cnt]==wc[0] && z[cnt+1]==0;
*pnPattern = cnt;
return 1;
}
#endif
#ifndef SQLITE_OMIT_VIRTUALTABLE
static int isMatchOfColumn(
Expr *pExpr
){
ExprList *pList;
if( pExpr->op!=TK_FUNCTION ){
return 0;
}
if( pExpr->token.n!=5 ||
sqlite3StrNICmp((const char*)pExpr->token.z,"match",5)!=0 ){
return 0;
}
pList = pExpr->pList;
if( pList->nExpr!=2 ){
return 0;
}
if( pList->a[1].pExpr->op != TK_COLUMN ){
return 0;
}
return 1;
}
#endif
static void transferJoinMarkings(Expr *pDerived, Expr *pBase){
pDerived->flags |= pBase->flags & EP_FromJoin;
pDerived->iRightJoinTable = pBase->iRightJoinTable;
}
#if !defined(SQLITE_OMIT_OR_OPTIMIZATION) && !defined(SQLITE_OMIT_SUBQUERY)
static int orTermIsOptCandidate(WhereTerm *pOrTerm, int iCursor, int iColumn){
int affLeft, affRight;
assert( pOrTerm->eOperator==WO_EQ );
if( pOrTerm->leftCursor!=iCursor ){
return 0;
}
if( pOrTerm->leftColumn!=iColumn ){
return 0;
}
affRight = sqlite3ExprAffinity(pOrTerm->pExpr->pRight);
if( affRight==0 ){
return 1;
}
affLeft = sqlite3ExprAffinity(pOrTerm->pExpr->pLeft);
if( affRight!=affLeft ){
return 0;
}
return 1;
}
static int orTermHasOkDuplicate(WhereClause *pOr, WhereTerm *pOrTerm){
if( pOrTerm->flags & TERM_COPIED ){
return 1;
}
if( (pOrTerm->flags & TERM_VIRTUAL)!=0
&& (pOr->a[pOrTerm->iParent].flags & TERM_OR_OK)!=0 ){
return 1;
}
return 0;
}
#endif
static void exprAnalyze(
SrcList *pSrc,
WhereClause *pWC,
int idxTerm
){
WhereTerm *pTerm = &pWC->a[idxTerm];
ExprMaskSet *pMaskSet = pWC->pMaskSet;
Expr *pExpr = pTerm->pExpr;
Bitmask prereqLeft;
Bitmask prereqAll;
int nPattern;
int isComplete;
int op;
if( sqlite3MallocFailed() ) return;
prereqLeft = exprTableUsage(pMaskSet, pExpr->pLeft);
op = pExpr->op;
if( op==TK_IN ){
assert( pExpr->pRight==0 );
pTerm->prereqRight = exprListTableUsage(pMaskSet, pExpr->pList)
| exprSelectTableUsage(pMaskSet, pExpr->pSelect);
}else if( op==TK_ISNULL ){
pTerm->prereqRight = 0;
}else{
pTerm->prereqRight = exprTableUsage(pMaskSet, pExpr->pRight);
}
prereqAll = exprTableUsage(pMaskSet, pExpr);
if( ExprHasProperty(pExpr, EP_FromJoin) ){
prereqAll |= getMask(pMaskSet, pExpr->iRightJoinTable);
}
pTerm->prereqAll = prereqAll;
pTerm->leftCursor = -1;
pTerm->iParent = -1;
pTerm->eOperator = 0;
if( allowedOp(op) && (pTerm->prereqRight & prereqLeft)==0 ){
Expr *pLeft = pExpr->pLeft;
Expr *pRight = pExpr->pRight;
if( pLeft->op==TK_COLUMN ){
pTerm->leftCursor = pLeft->iTable;
pTerm->leftColumn = pLeft->iColumn;
pTerm->eOperator = operatorMask(op);
}
if( pRight && pRight->op==TK_COLUMN ){
WhereTerm *pNew;
Expr *pDup;
if( pTerm->leftCursor>=0 ){
int idxNew;
pDup = sqlite3ExprDup(pExpr);
if( sqlite3MallocFailed() ){
sqlite3ExprDelete(pDup);
return;
}
idxNew = whereClauseInsert(pWC, pDup, TERM_VIRTUAL|TERM_DYNAMIC);
if( idxNew==0 ) return;
pNew = &pWC->a[idxNew];
pNew->iParent = idxTerm;
pTerm = &pWC->a[idxTerm];
pTerm->nChild = 1;
pTerm->flags |= TERM_COPIED;
}else{
pDup = pExpr;
pNew = pTerm;
}
exprCommute(pDup);
pLeft = pDup->pLeft;
pNew->leftCursor = pLeft->iTable;
pNew->leftColumn = pLeft->iColumn;
pNew->prereqRight = prereqLeft;
pNew->prereqAll = prereqAll;
pNew->eOperator = operatorMask(pDup->op);
}
}
#ifndef SQLITE_OMIT_BETWEEN_OPTIMIZATION
else if( pExpr->op==TK_BETWEEN ){
ExprList *pList = pExpr->pList;
int i;
static const u8 ops[] = {TK_GE, TK_LE};
assert( pList!=0 );
assert( pList->nExpr==2 );
for(i=0; i<2; i++){
Expr *pNewExpr;
int idxNew;
pNewExpr = sqlite3Expr(ops[i], sqlite3ExprDup(pExpr->pLeft),
sqlite3ExprDup(pList->a[i].pExpr), 0);
idxNew = whereClauseInsert(pWC, pNewExpr, TERM_VIRTUAL|TERM_DYNAMIC);
exprAnalyze(pSrc, pWC, idxNew);
pTerm = &pWC->a[idxTerm];
pWC->a[idxNew].iParent = idxTerm;
}
pTerm->nChild = 2;
}
#endif
#if !defined(SQLITE_OMIT_OR_OPTIMIZATION) && !defined(SQLITE_OMIT_SUBQUERY)
else if( pExpr->op==TK_OR ){
int ok;
int i, j;
int iColumn, iCursor;
WhereClause sOr;
WhereTerm *pOrTerm;
assert( (pTerm->flags & TERM_DYNAMIC)==0 );
whereClauseInit(&sOr, pWC->pParse, pMaskSet);
whereSplit(&sOr, pExpr, TK_OR);
exprAnalyzeAll(pSrc, &sOr);
assert( sOr.nTerm>=2 );
j = 0;
do{
assert( j<sOr.nTerm );
iColumn = sOr.a[j].leftColumn;
iCursor = sOr.a[j].leftCursor;
ok = iCursor>=0;
for(i=sOr.nTerm-1, pOrTerm=sOr.a; i>=0 && ok; i--, pOrTerm++){
if( pOrTerm->eOperator!=WO_EQ ){
goto or_not_possible;
}
if( orTermIsOptCandidate(pOrTerm, iCursor, iColumn) ){
pOrTerm->flags |= TERM_OR_OK;
}else if( orTermHasOkDuplicate(&sOr, pOrTerm) ){
pOrTerm->flags &= ~TERM_OR_OK;
}else{
ok = 0;
}
}
}while( !ok && (sOr.a[j++].flags & TERM_COPIED)!=0 && j<2 );
if( ok ){
ExprList *pList = 0;
Expr *pNew, *pDup;
Expr *pLeft = 0;
for(i=sOr.nTerm-1, pOrTerm=sOr.a; i>=0 && ok; i--, pOrTerm++){
if( (pOrTerm->flags & TERM_OR_OK)==0 ) continue;
pDup = sqlite3ExprDup(pOrTerm->pExpr->pRight);
pList = sqlite3ExprListAppend(pList, pDup, 0);
pLeft = pOrTerm->pExpr->pLeft;
}
assert( pLeft!=0 );
pDup = sqlite3ExprDup(pLeft);
pNew = sqlite3Expr(TK_IN, pDup, 0, 0);
if( pNew ){
int idxNew;
transferJoinMarkings(pNew, pExpr);
pNew->pList = pList;
idxNew = whereClauseInsert(pWC, pNew, TERM_VIRTUAL|TERM_DYNAMIC);
exprAnalyze(pSrc, pWC, idxNew);
pTerm = &pWC->a[idxTerm];
pWC->a[idxNew].iParent = idxTerm;
pTerm->nChild = 1;
}else{
sqlite3ExprListDelete(pList);
}
}
or_not_possible:
whereClauseClear(&sOr);
}
#endif
#ifndef SQLITE_OMIT_LIKE_OPTIMIZATION
if( isLikeOrGlob(pWC->pParse->db, pExpr, &nPattern, &isComplete) ){
Expr *pLeft, *pRight;
Expr *pStr1, *pStr2;
Expr *pNewExpr1, *pNewExpr2;
int idxNew1, idxNew2;
pLeft = pExpr->pList->a[1].pExpr;
pRight = pExpr->pList->a[0].pExpr;
pStr1 = sqlite3Expr(TK_STRING, 0, 0, 0);
if( pStr1 ){
sqlite3TokenCopy(&pStr1->token, &pRight->token);
pStr1->token.n = nPattern;
}
pStr2 = sqlite3ExprDup(pStr1);
if( pStr2 ){
assert( pStr2->token.dyn );
++*(u8*)&pStr2->token.z[nPattern-1];
}
pNewExpr1 = sqlite3Expr(TK_GE, sqlite3ExprDup(pLeft), pStr1, 0);
idxNew1 = whereClauseInsert(pWC, pNewExpr1, TERM_VIRTUAL|TERM_DYNAMIC);
exprAnalyze(pSrc, pWC, idxNew1);
pNewExpr2 = sqlite3Expr(TK_LT, sqlite3ExprDup(pLeft), pStr2, 0);
idxNew2 = whereClauseInsert(pWC, pNewExpr2, TERM_VIRTUAL|TERM_DYNAMIC);
exprAnalyze(pSrc, pWC, idxNew2);
pTerm = &pWC->a[idxTerm];
if( isComplete ){
pWC->a[idxNew1].iParent = idxTerm;
pWC->a[idxNew2].iParent = idxTerm;
pTerm->nChild = 2;
}
}
#endif
#ifndef SQLITE_OMIT_VIRTUALTABLE
if( isMatchOfColumn(pExpr) ){
int idxNew;
Expr *pRight, *pLeft;
WhereTerm *pNewTerm;
Bitmask prereqColumn, prereqExpr;
pRight = pExpr->pList->a[0].pExpr;
pLeft = pExpr->pList->a[1].pExpr;
prereqExpr = exprTableUsage(pMaskSet, pRight);
prereqColumn = exprTableUsage(pMaskSet, pLeft);
if( (prereqExpr & prereqColumn)==0 ){
Expr *pNewExpr;
pNewExpr = sqlite3Expr(TK_MATCH, 0, sqlite3ExprDup(pRight), 0);
idxNew = whereClauseInsert(pWC, pNewExpr, TERM_VIRTUAL|TERM_DYNAMIC);
pNewTerm = &pWC->a[idxNew];
pNewTerm->prereqRight = prereqExpr;
pNewTerm->leftCursor = pLeft->iTable;
pNewTerm->leftColumn = pLeft->iColumn;
pNewTerm->eOperator = WO_MATCH;
pNewTerm->iParent = idxTerm;
pTerm = &pWC->a[idxTerm];
pTerm->nChild = 1;
pTerm->flags |= TERM_COPIED;
pNewTerm->prereqAll = pTerm->prereqAll;
}
}
#endif
}
static int referencesOtherTables(
ExprList *pList,
ExprMaskSet *pMaskSet,
int iFirst,
int iBase
){
Bitmask allowed = ~getMask(pMaskSet, iBase);
while( iFirst<pList->nExpr ){
if( (exprTableUsage(pMaskSet, pList->a[iFirst++].pExpr)&allowed)!=0 ){
return 1;
}
}
return 0;
}
static int isSortingIndex(
Parse *pParse,
ExprMaskSet *pMaskSet,
Index *pIdx,
int base,
ExprList *pOrderBy,
int nEqCol,
int *pbRev
){
int i, j;
int sortOrder = 0;
int nTerm;
struct ExprList_item *pTerm;
sqlite3 *db = pParse->db;
assert( pOrderBy!=0 );
nTerm = pOrderBy->nExpr;
assert( nTerm>0 );
for(i=j=0, pTerm=pOrderBy->a; j<nTerm && i<=pIdx->nColumn; i++){
Expr *pExpr;
CollSeq *pColl;
int termSortOrder;
int iColumn;
int iSortOrder;
const char *zColl;
pExpr = pTerm->pExpr;
if( pExpr->op!=TK_COLUMN || pExpr->iTable!=base ){
break;
}
pColl = sqlite3ExprCollSeq(pParse, pExpr);
if( !pColl ){
pColl = db->pDfltColl;
}
if( i<pIdx->nColumn ){
iColumn = pIdx->aiColumn[i];
if( iColumn==pIdx->pTable->iPKey ){
iColumn = -1;
}
iSortOrder = pIdx->aSortOrder[i];
zColl = pIdx->azColl[i];
}else{
iColumn = -1;
iSortOrder = 0;
zColl = pColl->zName;
}
if( pExpr->iColumn!=iColumn || sqlite3StrICmp(pColl->zName, zColl) ){
if( i<nEqCol ){
continue;
}else{
return 0;
}
}
assert( pIdx->aSortOrder!=0 );
assert( pTerm->sortOrder==0 || pTerm->sortOrder==1 );
assert( iSortOrder==0 || iSortOrder==1 );
termSortOrder = iSortOrder ^ pTerm->sortOrder;
if( i>nEqCol ){
if( termSortOrder!=sortOrder ){
return 0;
}
}else{
sortOrder = termSortOrder;
}
j++;
pTerm++;
if( iColumn<0 && !referencesOtherTables(pOrderBy, pMaskSet, j, base) ){
j = nTerm;
}
}
*pbRev = sortOrder!=0;
if( j>=nTerm ){
return 1;
}
if( pIdx->onError!=OE_None && i==pIdx->nColumn
&& !referencesOtherTables(pOrderBy, pMaskSet, j, base) ){
return 1;
}
return 0;
}
static int sortableByRowid(
int base,
ExprList *pOrderBy,
ExprMaskSet *pMaskSet,
int *pbRev
){
Expr *p;
assert( pOrderBy!=0 );
assert( pOrderBy->nExpr>0 );
p = pOrderBy->a[0].pExpr;
if( p->op==TK_COLUMN && p->iTable==base && p->iColumn==-1
&& !referencesOtherTables(pOrderBy, pMaskSet, 1, base) ){
*pbRev = pOrderBy->a[0].sortOrder;
return 1;
}
return 0;
}
static double estLog(double N){
double logN = 1;
double x = 10;
while( N>x ){
logN += 1;
x *= 10;
}
return logN;
}
#if !defined(SQLITE_OMIT_VIRTUALTABLE) && defined(SQLITE_DEBUG)
static void TRACE_IDX_INPUTS(sqlite3_index_info *p){
int i;
if( !sqlite3_where_trace ) return;
for(i=0; i<p->nConstraint; i++){
sqlite3DebugPrintf(" constraint[%d]: col=%d termid=%d op=%d usabled=%d\n",
i,
p->aConstraint[i].iColumn,
p->aConstraint[i].iTermOffset,
p->aConstraint[i].op,
p->aConstraint[i].usable);
}
for(i=0; i<p->nOrderBy; i++){
sqlite3DebugPrintf(" orderby[%d]: col=%d desc=%d\n",
i,
p->aOrderBy[i].iColumn,
p->aOrderBy[i].desc);
}
}
static void TRACE_IDX_OUTPUTS(sqlite3_index_info *p){
int i;
if( !sqlite3_where_trace ) return;
for(i=0; i<p->nConstraint; i++){
sqlite3DebugPrintf(" usage[%d]: argvIdx=%d omit=%d\n",
i,
p->aConstraintUsage[i].argvIndex,
p->aConstraintUsage[i].omit);
}
sqlite3DebugPrintf(" idxNum=%d\n", p->idxNum);
sqlite3DebugPrintf(" idxStr=%s\n", p->idxStr);
sqlite3DebugPrintf(" orderByConsumed=%d\n", p->orderByConsumed);
sqlite3DebugPrintf(" estimatedCost=%g\n", p->estimatedCost);
}
#else
#define TRACE_IDX_INPUTS(A)
#define TRACE_IDX_OUTPUTS(A)
#endif
#ifndef SQLITE_OMIT_VIRTUALTABLE
static double bestVirtualIndex(
Parse *pParse,
WhereClause *pWC,
struct SrcList_item *pSrc,
Bitmask notReady,
ExprList *pOrderBy,
int orderByUsable,
sqlite3_index_info **ppIdxInfo
){
Table *pTab = pSrc->pTab;
sqlite3_index_info *pIdxInfo;
struct sqlite3_index_constraint *pIdxCons;
struct sqlite3_index_orderby *pIdxOrderBy;
struct sqlite3_index_constraint_usage *pUsage;
WhereTerm *pTerm;
int i, j;
int nOrderBy;
int rc;
pIdxInfo = *ppIdxInfo;
if( pIdxInfo==0 ){
WhereTerm *pTerm;
int nTerm;
WHERETRACE(("Recomputing index info for %s...\n", pTab->zName));
for(i=nTerm=0, pTerm=pWC->a; i<pWC->nTerm; i++, pTerm++){
if( pTerm->leftCursor != pSrc->iCursor ) continue;
if( pTerm->eOperator==WO_IN ) continue;
nTerm++;
}
nOrderBy = 0;
if( pOrderBy ){
for(i=0; i<pOrderBy->nExpr; i++){
Expr *pExpr = pOrderBy->a[i].pExpr;
if( pExpr->op!=TK_COLUMN || pExpr->iTable!=pSrc->iCursor ) break;
}
if( i==pOrderBy->nExpr ){
nOrderBy = pOrderBy->nExpr;
}
}
pIdxInfo = sqliteMalloc( sizeof(*pIdxInfo)
+ (sizeof(*pIdxCons) + sizeof(*pUsage))*nTerm
+ sizeof(*pIdxOrderBy)*nOrderBy );
if( pIdxInfo==0 ){
sqlite3ErrorMsg(pParse, "out of memory");
return 0.0;
}
*ppIdxInfo = pIdxInfo;
pIdxCons = (struct sqlite3_index_constraint*)&pIdxInfo[1];
pIdxOrderBy = (struct sqlite3_index_orderby*)&pIdxCons[nTerm];
pUsage = (struct sqlite3_index_constraint_usage*)&pIdxOrderBy[nOrderBy];
*(int*)&pIdxInfo->nConstraint = nTerm;
*(int*)&pIdxInfo->nOrderBy = nOrderBy;
*(struct sqlite3_index_constraint**)&pIdxInfo->aConstraint = pIdxCons;
*(struct sqlite3_index_orderby**)&pIdxInfo->aOrderBy = pIdxOrderBy;
*(struct sqlite3_index_constraint_usage**)&pIdxInfo->aConstraintUsage =
pUsage;
for(i=j=0, pTerm=pWC->a; i<pWC->nTerm; i++, pTerm++){
if( pTerm->leftCursor != pSrc->iCursor ) continue;
if( pTerm->eOperator==WO_IN ) continue;
pIdxCons[j].iColumn = pTerm->leftColumn;
pIdxCons[j].iTermOffset = i;
pIdxCons[j].op = pTerm->eOperator;
assert( WO_EQ==SQLITE_INDEX_CONSTRAINT_EQ );
assert( WO_LT==SQLITE_INDEX_CONSTRAINT_LT );
assert( WO_LE==SQLITE_INDEX_CONSTRAINT_LE );
assert( WO_GT==SQLITE_INDEX_CONSTRAINT_GT );
assert( WO_GE==SQLITE_INDEX_CONSTRAINT_GE );
assert( WO_MATCH==SQLITE_INDEX_CONSTRAINT_MATCH );
assert( pTerm->eOperator & (WO_EQ|WO_LT|WO_LE|WO_GT|WO_GE|WO_MATCH) );
j++;
}
for(i=0; i<nOrderBy; i++){
Expr *pExpr = pOrderBy->a[i].pExpr;
pIdxOrderBy[i].iColumn = pExpr->iColumn;
pIdxOrderBy[i].desc = pOrderBy->a[i].sortOrder;
}
}
assert( pTab->azModuleArg && pTab->azModuleArg[0] );
assert( pTab->pVtab );
#if 0
if( pTab->pVtab==0 ){
sqlite3ErrorMsg(pParse, "undefined module %s for table %s",
pTab->azModuleArg[0], pTab->zName);
return 0.0;
}
#endif
pIdxCons = *(struct sqlite3_index_constraint**)&pIdxInfo->aConstraint;
pUsage = pIdxInfo->aConstraintUsage;
for(i=0; i<pIdxInfo->nConstraint; i++, pIdxCons++){
j = pIdxCons->iTermOffset;
pTerm = &pWC->a[j];
pIdxCons->usable = (pTerm->prereqRight & notReady)==0;
}
memset(pUsage, 0, sizeof(pUsage[0])*pIdxInfo->nConstraint);
if( pIdxInfo->needToFreeIdxStr ){
sqlite3_free(pIdxInfo->idxStr);
}
pIdxInfo->idxStr = 0;
pIdxInfo->idxNum = 0;
pIdxInfo->needToFreeIdxStr = 0;
pIdxInfo->orderByConsumed = 0;
pIdxInfo->estimatedCost = SQLITE_BIG_DBL / 2.0;
nOrderBy = pIdxInfo->nOrderBy;
if( pIdxInfo->nOrderBy && !orderByUsable ){
*(int*)&pIdxInfo->nOrderBy = 0;
}
sqlite3SafetyOff(pParse->db);
WHERETRACE(("xBestIndex for %s\n", pTab->zName));
TRACE_IDX_INPUTS(pIdxInfo);
rc = pTab->pVtab->pModule->xBestIndex(pTab->pVtab, pIdxInfo);
TRACE_IDX_OUTPUTS(pIdxInfo);
if( rc!=SQLITE_OK ){
if( rc==SQLITE_NOMEM ){
sqlite3FailedMalloc();
}else {
sqlite3ErrorMsg(pParse, "%s", sqlite3ErrStr(rc));
}
sqlite3SafetyOn(pParse->db);
}else{
rc = sqlite3SafetyOn(pParse->db);
}
*(int*)&pIdxInfo->nOrderBy = nOrderBy;
return pIdxInfo->estimatedCost;
}
#endif
static double bestIndex(
Parse *pParse,
WhereClause *pWC,
struct SrcList_item *pSrc,
Bitmask notReady,
ExprList *pOrderBy,
Index **ppIndex,
int *pFlags,
int *pnEq
){
WhereTerm *pTerm;
Index *bestIdx = 0;
double lowestCost;
int bestFlags = 0;
int bestNEq = 0;
int iCur = pSrc->iCursor;
Index *pProbe;
int rev;
int flags;
int nEq;
int eqTermMask;
double cost;
WHERETRACE(("bestIndex: tbl=%s notReady=%x\n", pSrc->pTab->zName, notReady));
lowestCost = SQLITE_BIG_DBL;
pProbe = pSrc->pTab->pIndex;
if( pProbe==0 &&
findTerm(pWC, iCur, -1, 0, WO_EQ|WO_IN|WO_LT|WO_LE|WO_GT|WO_GE,0)==0 &&
(pOrderBy==0 || !sortableByRowid(iCur, pOrderBy, pWC->pMaskSet, &rev)) ){
*pFlags = 0;
*ppIndex = 0;
*pnEq = 0;
return 0.0;
}
pTerm = findTerm(pWC, iCur, -1, notReady, WO_EQ|WO_IN, 0);
if( pTerm ){
Expr *pExpr;
*ppIndex = 0;
bestFlags = WHERE_ROWID_EQ;
if( pTerm->eOperator & WO_EQ ){
*pFlags = WHERE_ROWID_EQ | WHERE_UNIQUE;
*pnEq = 1;
WHERETRACE(("... best is rowid\n"));
return 0.0;
}else if( (pExpr = pTerm->pExpr)->pList!=0 ){
lowestCost = pExpr->pList->nExpr;
lowestCost *= estLog(lowestCost);
}else{
lowestCost = 200;
}
WHERETRACE(("... rowid IN cost: %.9g\n", lowestCost));
}
cost = pProbe ? pProbe->aiRowEst[0] : 1000000;
WHERETRACE(("... table scan base cost: %.9g\n", cost));
flags = WHERE_ROWID_RANGE;
pTerm = findTerm(pWC, iCur, -1, notReady, WO_LT|WO_LE|WO_GT|WO_GE, 0);
if( pTerm ){
if( findTerm(pWC, iCur, -1, notReady, WO_LT|WO_LE, 0) ){
flags |= WHERE_TOP_LIMIT;
cost /= 3;
}
if( findTerm(pWC, iCur, -1, notReady, WO_GT|WO_GE, 0) ){
flags |= WHERE_BTM_LIMIT;
cost /= 3;
}
WHERETRACE(("... rowid range reduces cost to %.9g\n", cost));
}else{
flags = 0;
}
if( pOrderBy ){
if( sortableByRowid(iCur, pOrderBy, pWC->pMaskSet, &rev) ){
flags |= WHERE_ORDERBY|WHERE_ROWID_RANGE;
if( rev ){
flags |= WHERE_REVERSE;
}
}else{
cost += cost*estLog(cost);
WHERETRACE(("... sorting increases cost to %.9g\n", cost));
}
}
if( cost<lowestCost ){
lowestCost = cost;
bestFlags = flags;
}
if( (pSrc->jointype & JT_LEFT)!=0 ){
eqTermMask = WO_EQ|WO_IN;
}else{
eqTermMask = WO_EQ|WO_IN|WO_ISNULL;
}
for(; pProbe; pProbe=pProbe->pNext){
int i;
double inMultiplier = 1;
WHERETRACE(("... index %s:\n", pProbe->zName));
flags = 0;
for(i=0; i<pProbe->nColumn; i++){
int j = pProbe->aiColumn[i];
pTerm = findTerm(pWC, iCur, j, notReady, eqTermMask, pProbe);
if( pTerm==0 ) break;
flags |= WHERE_COLUMN_EQ;
if( pTerm->eOperator & WO_IN ){
Expr *pExpr = pTerm->pExpr;
flags |= WHERE_COLUMN_IN;
if( pExpr->pSelect!=0 ){
inMultiplier *= 25;
}else if( pExpr->pList!=0 ){
inMultiplier *= pExpr->pList->nExpr + 1;
}
}
}
cost = pProbe->aiRowEst[i] * inMultiplier * estLog(inMultiplier);
nEq = i;
if( pProbe->onError!=OE_None && (flags & WHERE_COLUMN_IN)==0
&& nEq==pProbe->nColumn ){
flags |= WHERE_UNIQUE;
}
WHERETRACE(("...... nEq=%d inMult=%.9g cost=%.9g\n", nEq, inMultiplier, cost));
if( nEq<pProbe->nColumn ){
int j = pProbe->aiColumn[nEq];
pTerm = findTerm(pWC, iCur, j, notReady, WO_LT|WO_LE|WO_GT|WO_GE, pProbe);
if( pTerm ){
flags |= WHERE_COLUMN_RANGE;
if( findTerm(pWC, iCur, j, notReady, WO_LT|WO_LE, pProbe) ){
flags |= WHERE_TOP_LIMIT;
cost /= 3;
}
if( findTerm(pWC, iCur, j, notReady, WO_GT|WO_GE, pProbe) ){
flags |= WHERE_BTM_LIMIT;
cost /= 3;
}
WHERETRACE(("...... range reduces cost to %.9g\n", cost));
}
}
if( pOrderBy ){
if( (flags & WHERE_COLUMN_IN)==0 &&
isSortingIndex(pParse,pWC->pMaskSet,pProbe,iCur,pOrderBy,nEq,&rev) ){
if( flags==0 ){
flags = WHERE_COLUMN_RANGE;
}
flags |= WHERE_ORDERBY;
if( rev ){
flags |= WHERE_REVERSE;
}
}else{
cost += cost*estLog(cost);
WHERETRACE(("...... orderby increases cost to %.9g\n", cost));
}
}
if( flags && pSrc->colUsed < (((Bitmask)1)<<(BMS-1)) ){
Bitmask m = pSrc->colUsed;
int j;
for(j=0; j<pProbe->nColumn; j++){
int x = pProbe->aiColumn[j];
if( x<BMS-1 ){
m &= ~(((Bitmask)1)<<x);
}
}
if( m==0 ){
flags |= WHERE_IDX_ONLY;
cost /= 2;
WHERETRACE(("...... idx-only reduces cost to %.9g\n", cost));
}
}
if( cost < lowestCost ){
bestIdx = pProbe;
lowestCost = cost;
assert( flags!=0 );
bestFlags = flags;
bestNEq = nEq;
}
}
*ppIndex = bestIdx;
WHERETRACE(("best index is %s, cost=%.9g, flags=%x, nEq=%d\n",
bestIdx ? bestIdx->zName : "(none)", lowestCost, bestFlags, bestNEq));
*pFlags = bestFlags | eqTermMask;
*pnEq = bestNEq;
return lowestCost;
}
static void disableTerm(WhereLevel *pLevel, WhereTerm *pTerm){
if( pTerm
&& (pTerm->flags & TERM_CODED)==0
&& (pLevel->iLeftJoin==0 || ExprHasProperty(pTerm->pExpr, EP_FromJoin))
){
pTerm->flags |= TERM_CODED;
if( pTerm->iParent>=0 ){
WhereTerm *pOther = &pTerm->pWC->a[pTerm->iParent];
if( (--pOther->nChild)==0 ){
disableTerm(pLevel, pOther);
}
}
}
}
static void buildIndexProbe(
Vdbe *v,
int nColumn,
Index *pIdx
){
sqlite3VdbeAddOp(v, OP_MakeRecord, nColumn, 0);
sqlite3IndexAffinityStr(v, pIdx);
}
static void codeEqualityTerm(
Parse *pParse,
WhereTerm *pTerm,
WhereLevel *pLevel
){
Expr *pX = pTerm->pExpr;
Vdbe *v = pParse->pVdbe;
if( pX->op==TK_EQ ){
sqlite3ExprCode(pParse, pX->pRight);
}else if( pX->op==TK_ISNULL ){
sqlite3VdbeAddOp(v, OP_Null, 0, 0);
#ifndef SQLITE_OMIT_SUBQUERY
}else{
int iTab;
struct InLoop *pIn;
assert( pX->op==TK_IN );
sqlite3CodeSubselect(pParse, pX);
iTab = pX->iTable;
sqlite3VdbeAddOp(v, OP_Rewind, iTab, 0);
VdbeComment((v, "# %.*s", pX->span.n, pX->span.z));
if( pLevel->nIn==0 ){
pLevel->nxt = sqlite3VdbeMakeLabel(v);
}
pLevel->nIn++;
pLevel->aInLoop = sqliteReallocOrFree(pLevel->aInLoop,
sizeof(pLevel->aInLoop[0])*pLevel->nIn);
pIn = pLevel->aInLoop;
if( pIn ){
pIn += pLevel->nIn - 1;
pIn->iCur = iTab;
pIn->topAddr = sqlite3VdbeAddOp(v, OP_Column, iTab, 0);
sqlite3VdbeAddOp(v, OP_IsNull, -1, 0);
}else{
pLevel->nIn = 0;
}
#endif
}
disableTerm(pLevel, pTerm);
}
static void codeAllEqualityTerms(
Parse *pParse,
WhereLevel *pLevel,
WhereClause *pWC,
Bitmask notReady
){
int nEq = pLevel->nEq;
int termsInMem = 0;
Vdbe *v = pParse->pVdbe;
Index *pIdx = pLevel->pIdx;
int iCur = pLevel->iTabCur;
WhereTerm *pTerm;
int j;
pLevel->iMem = pParse->nMem++;
if( pLevel->flags & WHERE_COLUMN_IN ){
pParse->nMem += pLevel->nEq;
termsInMem = 1;
}
assert( pIdx->nColumn>=nEq );
for(j=0; j<nEq; j++){
int k = pIdx->aiColumn[j];
pTerm = findTerm(pWC, iCur, k, notReady, pLevel->flags, pIdx);
if( pTerm==0 ) break;
assert( (pTerm->flags & TERM_CODED)==0 );
codeEqualityTerm(pParse, pTerm, pLevel);
if( (pTerm->eOperator & (WO_ISNULL|WO_IN))==0 ){
sqlite3VdbeAddOp(v, OP_IsNull, termsInMem ? -1 : -(j+1), pLevel->brk);
}
if( termsInMem ){
sqlite3VdbeAddOp(v, OP_MemStore, pLevel->iMem+j+1, 1);
}
}
if( termsInMem ){
for(j=0; j<nEq; j++){
sqlite3VdbeAddOp(v, OP_MemLoad, pLevel->iMem+j+1, 0);
}
}
}
#if defined(SQLITE_TEST)
char sqlite3_query_plan[BMS*2*40];
static int nQPlan = 0;
#endif
static void whereInfoFree(WhereInfo *pWInfo){
if( pWInfo ){
int i;
for(i=0; i<pWInfo->nLevel; i++){
sqlite3_index_info *pInfo = pWInfo->a[i].pIdxInfo;
if( pInfo ){
if( pInfo->needToFreeIdxStr ){
sqlite3_free(pInfo->idxStr);
}
sqliteFree(pInfo);
}
}
sqliteFree(pWInfo);
}
}
WhereInfo *sqlite3WhereBegin(
Parse *pParse,
SrcList *pTabList,
Expr *pWhere,
ExprList **ppOrderBy
){
int i;
WhereInfo *pWInfo;
Vdbe *v = pParse->pVdbe;
int brk, cont = 0;
Bitmask notReady;
WhereTerm *pTerm;
ExprMaskSet maskSet;
WhereClause wc;
struct SrcList_item *pTabItem;
WhereLevel *pLevel;
int iFrom;
int andFlags;
if( pTabList->nSrc>BMS ){
sqlite3ErrorMsg(pParse, "at most %d tables in a join", BMS);
return 0;
}
initMaskSet(&maskSet);
whereClauseInit(&wc, pParse, &maskSet);
whereSplit(&wc, pWhere, TK_AND);
pWInfo = sqliteMalloc( sizeof(WhereInfo) + pTabList->nSrc*sizeof(WhereLevel));
if( sqlite3MallocFailed() ){
goto whereBeginNoMem;
}
pWInfo->nLevel = pTabList->nSrc;
pWInfo->pParse = pParse;
pWInfo->pTabList = pTabList;
pWInfo->iBreak = sqlite3VdbeMakeLabel(v);
if( pWhere && (pTabList->nSrc==0 || sqlite3ExprIsConstant(pWhere)) ){
sqlite3ExprIfFalse(pParse, pWhere, pWInfo->iBreak, 1);
pWhere = 0;
}
for(i=0; i<pTabList->nSrc; i++){
createMask(&maskSet, pTabList->a[i].iCursor);
}
exprAnalyzeAll(pTabList, &wc);
if( sqlite3MallocFailed() ){
goto whereBeginNoMem;
}
notReady = ~(Bitmask)0;
pTabItem = pTabList->a;
pLevel = pWInfo->a;
andFlags = ~0;
WHERETRACE(("*** Optimizer Start ***\n"));
for(i=iFrom=0, pLevel=pWInfo->a; i<pTabList->nSrc; i++, pLevel++){
Index *pIdx;
int flags;
int nEq;
double cost;
int j;
Index *pBest = 0;
int bestFlags = 0;
int bestNEq = 0;
double lowestCost;
int bestJ = 0;
Bitmask m;
int once = 0;
sqlite3_index_info *pIndex;
lowestCost = SQLITE_BIG_DBL;
for(j=iFrom, pTabItem=&pTabList->a[j]; j<pTabList->nSrc; j++, pTabItem++){
int doNotReorder;
doNotReorder = (pTabItem->jointype & (JT_LEFT|JT_CROSS))!=0;
if( once && doNotReorder ) break;
m = getMask(&maskSet, pTabItem->iCursor);
if( (m & notReady)==0 ){
if( j==iFrom ) iFrom++;
continue;
}
assert( pTabItem->pTab );
#ifndef SQLITE_OMIT_VIRTUALTABLE
if( IsVirtual(pTabItem->pTab) ){
sqlite3_index_info **ppIdxInfo = &pWInfo->a[j].pIdxInfo;
cost = bestVirtualIndex(pParse, &wc, pTabItem, notReady,
ppOrderBy ? *ppOrderBy : 0, i==0,
ppIdxInfo);
flags = WHERE_VIRTUALTABLE;
pIndex = *ppIdxInfo;
if( pIndex && pIndex->orderByConsumed ){
flags = WHERE_VIRTUALTABLE | WHERE_ORDERBY;
}
pIdx = 0;
nEq = 0;
if( (SQLITE_BIG_DBL/2.0)<cost ){
cost = (SQLITE_BIG_DBL/2.0);
}
}else
#endif
{
cost = bestIndex(pParse, &wc, pTabItem, notReady,
(i==0 && ppOrderBy) ? *ppOrderBy : 0,
&pIdx, &flags, &nEq);
pIndex = 0;
}
if( cost<lowestCost ){
once = 1;
lowestCost = cost;
pBest = pIdx;
bestFlags = flags;
bestNEq = nEq;
bestJ = j;
pLevel->pBestIdx = pIndex;
}
if( doNotReorder ) break;
}
WHERETRACE(("*** Optimizer choose table %d for loop %d\n", bestJ,
pLevel-pWInfo->a));
if( (bestFlags & WHERE_ORDERBY)!=0 ){
*ppOrderBy = 0;
}
andFlags &= bestFlags;
pLevel->flags = bestFlags;
pLevel->pIdx = pBest;
pLevel->nEq = bestNEq;
pLevel->aInLoop = 0;
pLevel->nIn = 0;
if( pBest ){
pLevel->iIdxCur = pParse->nTab++;
}else{
pLevel->iIdxCur = -1;
}
notReady &= ~getMask(&maskSet, pTabList->a[bestJ].iCursor);
pLevel->iFrom = bestJ;
}
WHERETRACE(("*** Optimizer Finished ***\n"));
if( (andFlags & WHERE_UNIQUE)!=0 && ppOrderBy ){
*ppOrderBy = 0;
}
sqlite3CodeVerifySchema(pParse, -1);
for(i=0, pLevel=pWInfo->a; i<pTabList->nSrc; i++, pLevel++){
Table *pTab;
Index *pIx;
int iDb;
int iIdxCur = pLevel->iIdxCur;
#ifndef SQLITE_OMIT_EXPLAIN
if( pParse->explain==2 ){
char *zMsg;
struct SrcList_item *pItem = &pTabList->a[pLevel->iFrom];
zMsg = sqlite3MPrintf("TABLE %s", pItem->zName);
if( pItem->zAlias ){
zMsg = sqlite3MPrintf("%z AS %s", zMsg, pItem->zAlias);
}
if( (pIx = pLevel->pIdx)!=0 ){
zMsg = sqlite3MPrintf("%z WITH INDEX %s", zMsg, pIx->zName);
}else if( pLevel->flags & (WHERE_ROWID_EQ|WHERE_ROWID_RANGE) ){
zMsg = sqlite3MPrintf("%z USING PRIMARY KEY", zMsg);
}
#ifndef SQLITE_OMIT_VIRTUALTABLE
else if( pLevel->pBestIdx ){
sqlite3_index_info *pBestIdx = pLevel->pBestIdx;
zMsg = sqlite3MPrintf("%z VIRTUAL TABLE INDEX %d:%s", zMsg,
pBestIdx->idxNum, pBestIdx->idxStr);
}
#endif
if( pLevel->flags & WHERE_ORDERBY ){
zMsg = sqlite3MPrintf("%z ORDER BY", zMsg);
}
sqlite3VdbeOp3(v, OP_Explain, i, pLevel->iFrom, zMsg, P3_DYNAMIC);
}
#endif
pTabItem = &pTabList->a[pLevel->iFrom];
pTab = pTabItem->pTab;
iDb = sqlite3SchemaToIndex(pParse->db, pTab->pSchema);
if( pTab->isEphem || pTab->pSelect ) continue;
#ifndef SQLITE_OMIT_VIRTUALTABLE
if( pLevel->pBestIdx ){
int iCur = pTabItem->iCursor;
sqlite3VdbeOp3(v, OP_VOpen, iCur, 0, (const char*)pTab->pVtab, P3_VTAB);
}else
#endif
if( (pLevel->flags & WHERE_IDX_ONLY)==0 ){
sqlite3OpenTable(pParse, pTabItem->iCursor, iDb, pTab, OP_OpenRead);
if( pTab->nCol<(sizeof(Bitmask)*8) ){
Bitmask b = pTabItem->colUsed;
int n = 0;
for(; b; b=b>>1, n++){}
sqlite3VdbeChangeP2(v, sqlite3VdbeCurrentAddr(v)-1, n);
assert( n<=pTab->nCol );
}
}else{
sqlite3TableLock(pParse, iDb, pTab->tnum, 0, pTab->zName);
}
pLevel->iTabCur = pTabItem->iCursor;
if( (pIx = pLevel->pIdx)!=0 ){
KeyInfo *pKey = sqlite3IndexKeyinfo(pParse, pIx);
assert( pIx->pSchema==pTab->pSchema );
sqlite3VdbeAddOp(v, OP_Integer, iDb, 0);
VdbeComment((v, "# %s", pIx->zName));
sqlite3VdbeOp3(v, OP_OpenRead, iIdxCur, pIx->tnum,
(char*)pKey, P3_KEYINFO_HANDOFF);
}
if( (pLevel->flags & (WHERE_IDX_ONLY|WHERE_COLUMN_RANGE))!=0 ){
sqlite3VdbeAddOp(v, OP_SetNumColumns, iIdxCur, pIx->nColumn+1);
}
sqlite3CodeVerifySchema(pParse, iDb);
}
pWInfo->iTop = sqlite3VdbeCurrentAddr(v);
notReady = ~(Bitmask)0;
for(i=0, pLevel=pWInfo->a; i<pTabList->nSrc; i++, pLevel++){
int j;
int iCur = pTabItem->iCursor;
Index *pIdx;
int nxt;
int iIdxCur;
int omitTable;
int bRev;
pTabItem = &pTabList->a[pLevel->iFrom];
iCur = pTabItem->iCursor;
pIdx = pLevel->pIdx;
iIdxCur = pLevel->iIdxCur;
bRev = (pLevel->flags & WHERE_REVERSE)!=0;
omitTable = (pLevel->flags & WHERE_IDX_ONLY)!=0;
brk = pLevel->brk = pLevel->nxt = sqlite3VdbeMakeLabel(v);
cont = pLevel->cont = sqlite3VdbeMakeLabel(v);
if( pLevel->iFrom>0 && (pTabItem[0].jointype & JT_LEFT)!=0 ){
if( !pParse->nMem ) pParse->nMem++;
pLevel->iLeftJoin = pParse->nMem++;
sqlite3VdbeAddOp(v, OP_MemInt, 0, pLevel->iLeftJoin);
VdbeComment((v, "# init LEFT JOIN no-match flag"));
}
#ifndef SQLITE_OMIT_VIRTUALTABLE
if( pLevel->pBestIdx ){
int j;
sqlite3_index_info *pBestIdx = pLevel->pBestIdx;
int nConstraint = pBestIdx->nConstraint;
struct sqlite3_index_constraint_usage *aUsage =
pBestIdx->aConstraintUsage;
const struct sqlite3_index_constraint *aConstraint =
pBestIdx->aConstraint;
for(j=1; j<=nConstraint; j++){
int k;
for(k=0; k<nConstraint; k++){
if( aUsage[k].argvIndex==j ){
int iTerm = aConstraint[k].iTermOffset;
sqlite3ExprCode(pParse, wc.a[iTerm].pExpr->pRight);
break;
}
}
if( k==nConstraint ) break;
}
sqlite3VdbeAddOp(v, OP_Integer, j-1, 0);
sqlite3VdbeAddOp(v, OP_Integer, pBestIdx->idxNum, 0);
sqlite3VdbeOp3(v, OP_VFilter, iCur, brk, pBestIdx->idxStr,
pBestIdx->needToFreeIdxStr ? P3_MPRINTF : P3_STATIC);
pBestIdx->needToFreeIdxStr = 0;
for(j=0; j<pBestIdx->nConstraint; j++){
if( aUsage[j].omit ){
int iTerm = aConstraint[j].iTermOffset;
disableTerm(pLevel, &wc.a[iTerm]);
}
}
pLevel->op = OP_VNext;
pLevel->p1 = iCur;
pLevel->p2 = sqlite3VdbeCurrentAddr(v);
}else
#endif
if( pLevel->flags & WHERE_ROWID_EQ ){
pTerm = findTerm(&wc, iCur, -1, notReady, WO_EQ|WO_IN, 0);
assert( pTerm!=0 );
assert( pTerm->pExpr!=0 );
assert( pTerm->leftCursor==iCur );
assert( omitTable==0 );
codeEqualityTerm(pParse, pTerm, pLevel);
nxt = pLevel->nxt;
sqlite3VdbeAddOp(v, OP_MustBeInt, 1, nxt);
sqlite3VdbeAddOp(v, OP_NotExists, iCur, nxt);
VdbeComment((v, "pk"));
pLevel->op = OP_Noop;
}else if( pLevel->flags & WHERE_ROWID_RANGE ){
int testOp = OP_Noop;
int start;
WhereTerm *pStart, *pEnd;
assert( omitTable==0 );
pStart = findTerm(&wc, iCur, -1, notReady, WO_GT|WO_GE, 0);
pEnd = findTerm(&wc, iCur, -1, notReady, WO_LT|WO_LE, 0);
if( bRev ){
pTerm = pStart;
pStart = pEnd;
pEnd = pTerm;
}
if( pStart ){
Expr *pX;
pX = pStart->pExpr;
assert( pX!=0 );
assert( pStart->leftCursor==iCur );
sqlite3ExprCode(pParse, pX->pRight);
sqlite3VdbeAddOp(v, OP_ForceInt, pX->op==TK_LE || pX->op==TK_GT, brk);
sqlite3VdbeAddOp(v, bRev ? OP_MoveLt : OP_MoveGe, iCur, brk);
VdbeComment((v, "pk"));
disableTerm(pLevel, pStart);
}else{
sqlite3VdbeAddOp(v, bRev ? OP_Last : OP_Rewind, iCur, brk);
}
if( pEnd ){
Expr *pX;
pX = pEnd->pExpr;
assert( pX!=0 );
assert( pEnd->leftCursor==iCur );
sqlite3ExprCode(pParse, pX->pRight);
pLevel->iMem = pParse->nMem++;
sqlite3VdbeAddOp(v, OP_MemStore, pLevel->iMem, 1);
if( pX->op==TK_LT || pX->op==TK_GT ){
testOp = bRev ? OP_Le : OP_Ge;
}else{
testOp = bRev ? OP_Lt : OP_Gt;
}
disableTerm(pLevel, pEnd);
}
start = sqlite3VdbeCurrentAddr(v);
pLevel->op = bRev ? OP_Prev : OP_Next;
pLevel->p1 = iCur;
pLevel->p2 = start;
if( testOp!=OP_Noop ){
sqlite3VdbeAddOp(v, OP_Rowid, iCur, 0);
sqlite3VdbeAddOp(v, OP_MemLoad, pLevel->iMem, 0);
sqlite3VdbeAddOp(v, testOp, SQLITE_AFF_NUMERIC, brk);
}
}else if( pLevel->flags & WHERE_COLUMN_RANGE ){
int start;
int nEq = pLevel->nEq;
int topEq=0;
int btmEq=0;
int topOp, btmOp;
int testOp;
int topLimit = (pLevel->flags & WHERE_TOP_LIMIT)!=0;
int btmLimit = (pLevel->flags & WHERE_BTM_LIMIT)!=0;
codeAllEqualityTerms(pParse, pLevel, &wc, notReady);
for(j=0; j<nEq; j++){
sqlite3VdbeAddOp(v, OP_Dup, nEq-1, 0);
}
if( pIdx->aSortOrder[nEq]==SQLITE_SO_ASC ){
topOp = WO_LT|WO_LE;
btmOp = WO_GT|WO_GE;
}else{
topOp = WO_GT|WO_GE;
btmOp = WO_LT|WO_LE;
SWAP(int, topLimit, btmLimit);
}
nxt = pLevel->nxt;
if( topLimit ){
Expr *pX;
int k = pIdx->aiColumn[j];
pTerm = findTerm(&wc, iCur, k, notReady, topOp, pIdx);
assert( pTerm!=0 );
pX = pTerm->pExpr;
assert( (pTerm->flags & TERM_CODED)==0 );
sqlite3ExprCode(pParse, pX->pRight);
sqlite3VdbeAddOp(v, OP_IsNull, -(nEq+1), nxt);
topEq = pTerm->eOperator & (WO_LE|WO_GE);
disableTerm(pLevel, pTerm);
testOp = OP_IdxGE;
}else{
testOp = nEq>0 ? OP_IdxGE : OP_Noop;
topEq = 1;
}
if( testOp!=OP_Noop ){
int nCol = nEq + topLimit;
pLevel->iMem = pParse->nMem++;
buildIndexProbe(v, nCol, pIdx);
if( bRev ){
int op = topEq ? OP_MoveLe : OP_MoveLt;
sqlite3VdbeAddOp(v, op, iIdxCur, nxt);
}else{
sqlite3VdbeAddOp(v, OP_MemStore, pLevel->iMem, 1);
}
}else if( bRev ){
sqlite3VdbeAddOp(v, OP_Last, iIdxCur, brk);
}
if( btmLimit ){
Expr *pX;
int k = pIdx->aiColumn[j];
pTerm = findTerm(&wc, iCur, k, notReady, btmOp, pIdx);
assert( pTerm!=0 );
pX = pTerm->pExpr;
assert( (pTerm->flags & TERM_CODED)==0 );
sqlite3ExprCode(pParse, pX->pRight);
sqlite3VdbeAddOp(v, OP_IsNull, -(nEq+1), nxt);
btmEq = pTerm->eOperator & (WO_LE|WO_GE);
disableTerm(pLevel, pTerm);
}else{
btmEq = 1;
}
if( nEq>0 || btmLimit ){
int nCol = nEq + btmLimit;
buildIndexProbe(v, nCol, pIdx);
if( bRev ){
pLevel->iMem = pParse->nMem++;
sqlite3VdbeAddOp(v, OP_MemStore, pLevel->iMem, 1);
testOp = OP_IdxLT;
}else{
int op = btmEq ? OP_MoveGe : OP_MoveGt;
sqlite3VdbeAddOp(v, op, iIdxCur, nxt);
}
}else if( bRev ){
testOp = OP_Noop;
}else{
sqlite3VdbeAddOp(v, OP_Rewind, iIdxCur, brk);
}
start = sqlite3VdbeCurrentAddr(v);
if( testOp!=OP_Noop ){
sqlite3VdbeAddOp(v, OP_MemLoad, pLevel->iMem, 0);
sqlite3VdbeAddOp(v, testOp, iIdxCur, nxt);
if( (topEq && !bRev) || (!btmEq && bRev) ){
sqlite3VdbeChangeP3(v, -1, "+", P3_STATIC);
}
}
if( topLimit | btmLimit ){
sqlite3VdbeAddOp(v, OP_Column, iIdxCur, nEq);
sqlite3VdbeAddOp(v, OP_IsNull, 1, cont);
}
if( !omitTable ){
sqlite3VdbeAddOp(v, OP_IdxRowid, iIdxCur, 0);
sqlite3VdbeAddOp(v, OP_MoveGe, iCur, 0);
}
pLevel->op = bRev ? OP_Prev : OP_Next;
pLevel->p1 = iIdxCur;
pLevel->p2 = start;
}else if( pLevel->flags & WHERE_COLUMN_EQ ){
int start;
int nEq = pLevel->nEq;
codeAllEqualityTerms(pParse, pLevel, &wc, notReady);
nxt = pLevel->nxt;
buildIndexProbe(v, nEq, pIdx);
sqlite3VdbeAddOp(v, OP_MemStore, pLevel->iMem, 0);
if( bRev ){
sqlite3VdbeAddOp(v, OP_MoveLe, iIdxCur, nxt);
start = sqlite3VdbeAddOp(v, OP_MemLoad, pLevel->iMem, 0);
sqlite3VdbeAddOp(v, OP_IdxLT, iIdxCur, nxt);
pLevel->op = OP_Prev;
}else{
sqlite3VdbeAddOp(v, OP_MoveGe, iIdxCur, nxt);
start = sqlite3VdbeAddOp(v, OP_MemLoad, pLevel->iMem, 0);
sqlite3VdbeOp3(v, OP_IdxGE, iIdxCur, nxt, "+", P3_STATIC);
pLevel->op = OP_Next;
}
if( !omitTable ){
sqlite3VdbeAddOp(v, OP_IdxRowid, iIdxCur, 0);
sqlite3VdbeAddOp(v, OP_MoveGe, iCur, 0);
}
pLevel->p1 = iIdxCur;
pLevel->p2 = start;
}else{
assert( omitTable==0 );
assert( bRev==0 );
pLevel->op = OP_Next;
pLevel->p1 = iCur;
pLevel->p2 = 1 + sqlite3VdbeAddOp(v, OP_Rewind, iCur, brk);
}
notReady &= ~getMask(&maskSet, iCur);
for(pTerm=wc.a, j=wc.nTerm; j>0; j--, pTerm++){
Expr *pE;
if( pTerm->flags & (TERM_VIRTUAL|TERM_CODED) ) continue;
if( (pTerm->prereqAll & notReady)!=0 ) continue;
pE = pTerm->pExpr;
assert( pE!=0 );
if( pLevel->iLeftJoin && !ExprHasProperty(pE, EP_FromJoin) ){
continue;
}
sqlite3ExprIfFalse(pParse, pE, cont, 1);
pTerm->flags |= TERM_CODED;
}
if( pLevel->iLeftJoin ){
pLevel->top = sqlite3VdbeCurrentAddr(v);
sqlite3VdbeAddOp(v, OP_MemInt, 1, pLevel->iLeftJoin);
VdbeComment((v, "# record LEFT JOIN hit"));
for(pTerm=wc.a, j=0; j<wc.nTerm; j++, pTerm++){
if( pTerm->flags & (TERM_VIRTUAL|TERM_CODED) ) continue;
if( (pTerm->prereqAll & notReady)!=0 ) continue;
assert( pTerm->pExpr );
sqlite3ExprIfFalse(pParse, pTerm->pExpr, cont, 1);
pTerm->flags |= TERM_CODED;
}
}
}
#ifdef SQLITE_TEST
for(i=0; i<pTabList->nSrc; i++){
char *z;
int n;
pLevel = &pWInfo->a[i];
pTabItem = &pTabList->a[pLevel->iFrom];
z = pTabItem->zAlias;
if( z==0 ) z = pTabItem->pTab->zName;
n = strlen(z);
if( n+nQPlan < sizeof(sqlite3_query_plan)-10 ){
if( pLevel->flags & WHERE_IDX_ONLY ){
strcpy(&sqlite3_query_plan[nQPlan], "{}");
nQPlan += 2;
}else{
strcpy(&sqlite3_query_plan[nQPlan], z);
nQPlan += n;
}
sqlite3_query_plan[nQPlan++] = ' ';
}
if( pLevel->flags & (WHERE_ROWID_EQ|WHERE_ROWID_RANGE) ){
strcpy(&sqlite3_query_plan[nQPlan], "* ");
nQPlan += 2;
}else if( pLevel->pIdx==0 ){
strcpy(&sqlite3_query_plan[nQPlan], "{} ");
nQPlan += 3;
}else{
n = strlen(pLevel->pIdx->zName);
if( n+nQPlan < sizeof(sqlite3_query_plan)-2 ){
strcpy(&sqlite3_query_plan[nQPlan], pLevel->pIdx->zName);
nQPlan += n;
sqlite3_query_plan[nQPlan++] = ' ';
}
}
}
while( nQPlan>0 && sqlite3_query_plan[nQPlan-1]==' ' ){
sqlite3_query_plan[--nQPlan] = 0;
}
sqlite3_query_plan[nQPlan] = 0;
nQPlan = 0;
#endif
pWInfo->iContinue = cont;
whereClauseClear(&wc);
return pWInfo;
whereBeginNoMem:
whereClauseClear(&wc);
whereInfoFree(pWInfo);
return 0;
}
void sqlite3WhereEnd(WhereInfo *pWInfo){
Vdbe *v = pWInfo->pParse->pVdbe;
int i;
WhereLevel *pLevel;
SrcList *pTabList = pWInfo->pTabList;
for(i=pTabList->nSrc-1; i>=0; i--){
pLevel = &pWInfo->a[i];
sqlite3VdbeResolveLabel(v, pLevel->cont);
if( pLevel->op!=OP_Noop ){
sqlite3VdbeAddOp(v, pLevel->op, pLevel->p1, pLevel->p2);
}
if( pLevel->nIn ){
struct InLoop *pIn;
int j;
sqlite3VdbeResolveLabel(v, pLevel->nxt);
for(j=pLevel->nIn, pIn=&pLevel->aInLoop[j-1]; j>0; j--, pIn--){
sqlite3VdbeJumpHere(v, pIn->topAddr+1);
sqlite3VdbeAddOp(v, OP_Next, pIn->iCur, pIn->topAddr);
sqlite3VdbeJumpHere(v, pIn->topAddr-1);
}
sqliteFree(pLevel->aInLoop);
}
sqlite3VdbeResolveLabel(v, pLevel->brk);
if( pLevel->iLeftJoin ){
int addr;
addr = sqlite3VdbeAddOp(v, OP_IfMemPos, pLevel->iLeftJoin, 0);
sqlite3VdbeAddOp(v, OP_NullRow, pTabList->a[i].iCursor, 0);
if( pLevel->iIdxCur>=0 ){
sqlite3VdbeAddOp(v, OP_NullRow, pLevel->iIdxCur, 0);
}
sqlite3VdbeAddOp(v, OP_Goto, 0, pLevel->top);
sqlite3VdbeJumpHere(v, addr);
}
}
sqlite3VdbeResolveLabel(v, pWInfo->iBreak);
for(i=0, pLevel=pWInfo->a; i<pTabList->nSrc; i++, pLevel++){
struct SrcList_item *pTabItem = &pTabList->a[pLevel->iFrom];
Table *pTab = pTabItem->pTab;
assert( pTab!=0 );
if( pTab->isEphem || pTab->pSelect ) continue;
if( (pLevel->flags & WHERE_IDX_ONLY)==0 ){
sqlite3VdbeAddOp(v, OP_Close, pTabItem->iCursor, 0);
}
if( pLevel->pIdx!=0 ){
sqlite3VdbeAddOp(v, OP_Close, pLevel->iIdxCur, 0);
}
if( pLevel->flags & WHERE_IDX_ONLY ){
int k, j, last;
VdbeOp *pOp;
Index *pIdx = pLevel->pIdx;
assert( pIdx!=0 );
pOp = sqlite3VdbeGetOp(v, pWInfo->iTop);
last = sqlite3VdbeCurrentAddr(v);
for(k=pWInfo->iTop; k<last; k++, pOp++){
if( pOp->p1!=pLevel->iTabCur ) continue;
if( pOp->opcode==OP_Column ){
pOp->p1 = pLevel->iIdxCur;
for(j=0; j<pIdx->nColumn; j++){
if( pOp->p2==pIdx->aiColumn[j] ){
pOp->p2 = j;
break;
}
}
}else if( pOp->opcode==OP_Rowid ){
pOp->p1 = pLevel->iIdxCur;
pOp->opcode = OP_IdxRowid;
}else if( pOp->opcode==OP_NullRow ){
pOp->opcode = OP_Noop;
}
}
}
}
whereInfoFree(pWInfo);
return;
}