diff options
Diffstat (limited to 'third_party/sqlite/src/select.c')
| -rw-r--r-- | third_party/sqlite/src/select.c | 2408 |
1 files changed, 1179 insertions, 1229 deletions
diff --git a/third_party/sqlite/src/select.c b/third_party/sqlite/src/select.c index 5a8ddf0..f470bef 100644 --- a/third_party/sqlite/src/select.c +++ b/third_party/sqlite/src/select.c @@ -12,7 +12,7 @@ ** This file contains C code routines that are called by the parser ** to handle SELECT statements in SQLite. ** -** $Id: select.c,v 1.463 2008/08/04 03:51:24 danielk1977 Exp $ +** $Id: select.c,v 1.526 2009/08/01 15:09:58 drh Exp $ */ #include "sqliteInt.h" @@ -37,7 +37,7 @@ static void clearSelect(sqlite3 *db, Select *p){ ** Initialize a SelectDest structure. */ void sqlite3SelectDestInit(SelectDest *pDest, int eDest, int iParm){ - pDest->eDest = eDest; + pDest->eDest = (u8)eDest; pDest->iParm = iParm; pDest->affinity = 0; pDest->iMem = 0; @@ -65,13 +65,13 @@ Select *sqlite3SelectNew( Select standin; sqlite3 *db = pParse->db; pNew = sqlite3DbMallocZero(db, sizeof(*pNew) ); - assert( !pOffset || pLimit ); /* Can't have OFFSET without LIMIT. */ + assert( db->mallocFailed || !pOffset || pLimit ); /* OFFSET implies LIMIT */ if( pNew==0 ){ pNew = &standin; memset(pNew, 0, sizeof(*pNew)); } if( pEList==0 ){ - pEList = sqlite3ExprListAppend(pParse, 0, sqlite3Expr(db,TK_ALL,0,0,0), 0); + pEList = sqlite3ExprListAppend(pParse, 0, sqlite3Expr(db,TK_ALL,0)); } pNew->pEList = pEList; pNew->pSrc = pSrc; @@ -79,16 +79,17 @@ Select *sqlite3SelectNew( pNew->pGroupBy = pGroupBy; pNew->pHaving = pHaving; pNew->pOrderBy = pOrderBy; - pNew->isDistinct = isDistinct; + pNew->selFlags = isDistinct ? SF_Distinct : 0; pNew->op = TK_SELECT; - assert( pOffset==0 || pLimit!=0 ); pNew->pLimit = pLimit; pNew->pOffset = pOffset; + assert( pOffset==0 || pLimit!=0 ); pNew->addrOpenEphm[0] = -1; pNew->addrOpenEphm[1] = -1; pNew->addrOpenEphm[2] = -1; - if( pNew==&standin) { + if( db->mallocFailed ) { clearSelect(db, pNew); + if( pNew!=&standin ) sqlite3DbFree(db, pNew); pNew = 0; } return pNew; @@ -125,18 +126,20 @@ int sqlite3JoinType(Parse *pParse, Token *pA, Token *pB, Token *pC){ int jointype = 0; Token *apAll[3]; Token *p; + /* 0123456789 123456789 123456789 123 */ + static const char zKeyText[] = "naturaleftouterightfullinnercross"; static const struct { - const char zKeyword[8]; - u8 nChar; - u8 code; - } keywords[] = { - { "natural", 7, JT_NATURAL }, - { "left", 4, JT_LEFT|JT_OUTER }, - { "right", 5, JT_RIGHT|JT_OUTER }, - { "full", 4, JT_LEFT|JT_RIGHT|JT_OUTER }, - { "outer", 5, JT_OUTER }, - { "inner", 5, JT_INNER }, - { "cross", 5, JT_INNER|JT_CROSS }, + u8 i; /* Beginning of keyword text in zKeyText[] */ + u8 nChar; /* Length of the keyword in characters */ + u8 code; /* Join type mask */ + } aKeyword[] = { + /* natural */ { 0, 7, JT_NATURAL }, + /* left */ { 6, 4, JT_LEFT|JT_OUTER }, + /* outer */ { 10, 5, JT_OUTER }, + /* right */ { 14, 5, JT_RIGHT|JT_OUTER }, + /* full */ { 19, 4, JT_LEFT|JT_RIGHT|JT_OUTER }, + /* inner */ { 23, 5, JT_INNER }, + /* cross */ { 28, 5, JT_INNER|JT_CROSS }, }; int i, j; apAll[0] = pA; @@ -144,14 +147,15 @@ int sqlite3JoinType(Parse *pParse, Token *pA, Token *pB, Token *pC){ apAll[2] = pC; for(i=0; i<3 && apAll[i]; i++){ p = apAll[i]; - for(j=0; j<sizeof(keywords)/sizeof(keywords[0]); j++){ - if( p->n==keywords[j].nChar - && sqlite3StrNICmp((char*)p->z, keywords[j].zKeyword, p->n)==0 ){ - jointype |= keywords[j].code; + for(j=0; j<ArraySize(aKeyword); j++){ + if( p->n==aKeyword[j].nChar + && sqlite3StrNICmp((char*)p->z, &zKeyText[aKeyword[j].i], p->n)==0 ){ + jointype |= aKeyword[j].code; break; } } - if( j>=sizeof(keywords)/sizeof(keywords[0]) ){ + testcase( j==0 || j==1 || j==2 || j==3 || j==4 || j==5 || j==6 ); + if( j>=ArraySize(aKeyword) ){ jointype |= JT_ERROR; break; } @@ -166,7 +170,8 @@ int sqlite3JoinType(Parse *pParse, Token *pA, Token *pB, Token *pC){ sqlite3ErrorMsg(pParse, "unknown or unsupported join type: " "%T %T%s%T", pA, pB, zSp, pC); jointype = JT_INNER; - }else if( jointype & JT_RIGHT ){ + }else if( (jointype & JT_OUTER)!=0 + && (jointype & (JT_LEFT|JT_RIGHT))!=JT_LEFT ){ sqlite3ErrorMsg(pParse, "RIGHT and FULL OUTER JOINs are not currently supported"); jointype = JT_INNER; @@ -187,55 +192,10 @@ static int columnIndex(Table *pTab, const char *zCol){ } /* -** Set the value of a token to a '\000'-terminated string. -*/ -static void setToken(Token *p, const char *z){ - p->z = (u8*)z; - p->n = z ? strlen(z) : 0; - p->dyn = 0; -} - -/* -** Set the token to the double-quoted and escaped version of the string pointed -** to by z. For example; -** -** {a"bc} -> {"a""bc"} -*/ -static void setQuotedToken(Parse *pParse, Token *p, const char *z){ - - /* Check if the string contains any " characters. If it does, then - ** this function will malloc space to create a quoted version of - ** the string in. Otherwise, save a call to sqlite3MPrintf() by - ** just copying the pointer to the string. - */ - const char *z2 = z; - while( *z2 ){ - if( *z2=='"' ) break; - z2++; - } - - if( *z2 ){ - /* String contains " characters - copy and quote the string. */ - p->z = (u8 *)sqlite3MPrintf(pParse->db, "\"%w\"", z); - if( p->z ){ - p->n = strlen((char *)p->z); - p->dyn = 1; - } - }else{ - /* String contains no " characters - copy the pointer. */ - p->z = (u8*)z; - p->n = (z2 - z); - p->dyn = 0; - } -} - -/* ** Create an expression node for an identifier with the name of zName */ Expr *sqlite3CreateIdExpr(Parse *pParse, const char *zName){ - Token dummy; - setToken(&dummy, zName); - return sqlite3PExpr(pParse, TK_ID, 0, 0, &dummy); + return sqlite3Expr(pParse->db, TK_ID, zName); } /* @@ -272,7 +232,9 @@ static void addWhereTerm( pE = sqlite3PExpr(pParse, TK_EQ, pE1c, pE2c, 0); if( pE && isOuterJoin ){ ExprSetProperty(pE, EP_FromJoin); - pE->iRightJoinTable = iRightJoinTable; + assert( !ExprHasAnyProperty(pE, EP_TokenOnly|EP_Reduced) ); + ExprSetIrreducible(pE); + pE->iRightJoinTable = (i16)iRightJoinTable; } *ppExpr = sqlite3ExprAnd(pParse->db,*ppExpr, pE); } @@ -306,7 +268,9 @@ static void addWhereTerm( static void setJoinExpr(Expr *p, int iTable){ while( p ){ ExprSetProperty(p, EP_FromJoin); - p->iRightJoinTable = iTable; + assert( !ExprHasAnyProperty(p, EP_TokenOnly|EP_Reduced) ); + ExprSetIrreducible(p); + p->iRightJoinTable = (i16)iTable; setJoinExpr(p->pLeft, iTable); p = p->pRight; } @@ -340,7 +304,7 @@ static int sqliteProcessJoin(Parse *pParse, Select *p){ Table *pRightTab = pRight->pTab; int isOuter; - if( pLeftTab==0 || pRightTab==0 ) continue; + if( NEVER(pLeftTab==0 || pRightTab==0) ) continue; isOuter = (pRight->jointype & JT_OUTER)!=0; /* When the NATURAL keyword is present, add WHERE clause terms for @@ -419,6 +383,7 @@ static void pushOntoSorter( int nExpr = pOrderBy->nExpr; int regBase = sqlite3GetTempRange(pParse, nExpr+2); int regRecord = sqlite3GetTempReg(pParse); + sqlite3ExprCacheClear(pParse); sqlite3ExprCodeExprList(pParse, pOrderBy, regBase, 0); sqlite3VdbeAddOp2(v, OP_Sequence, pOrderBy->iECursor, regBase+nExpr); sqlite3ExprCodeMove(pParse, regData, regBase+nExpr+1, 1); @@ -540,7 +505,8 @@ static void selectInnerLoop( int iParm = pDest->iParm; /* First argument to disposal method */ int nResultCol; /* Number of result columns */ - if( v==0 ) return; + assert( v ); + if( NEVER(v==0) ) return; assert( pEList!=0 ); hasDistinct = distinct>=0; if( pOrderBy==0 && !hasDistinct ){ @@ -558,11 +524,8 @@ static void selectInnerLoop( pDest->iMem = pParse->nMem+1; pDest->nMem = nResultCol; pParse->nMem += nResultCol; - }else if( pDest->nMem!=nResultCol ){ - /* This happens when two SELECTs of a compound SELECT have differing - ** numbers of result columns. The error message will be generated by - ** a higher-level routine. */ - return; + }else{ + assert( pDest->nMem==nResultCol ); } regResult = pDest->iMem; if( nColumn>0 ){ @@ -573,7 +536,8 @@ static void selectInnerLoop( /* If the destination is an EXISTS(...) expression, the actual ** values returned by the SELECT are not required. */ - sqlite3ExprCodeExprList(pParse, pEList, regResult, eDest==SRT_Callback); + sqlite3ExprCacheClear(pParse); + sqlite3ExprCodeExprList(pParse, pEList, regResult, eDest==SRT_Output); } nColumn = nResultCol; @@ -623,6 +587,8 @@ static void selectInnerLoop( case SRT_Table: case SRT_EphemTab: { int r1 = sqlite3GetTempReg(pParse); + testcase( eDest==SRT_Table ); + testcase( eDest==SRT_EphemTab ); sqlite3VdbeAddOp3(v, OP_MakeRecord, regResult, nColumn, r1); if( pOrderBy ){ pushOntoSorter(pParse, pOrderBy, p, r1); @@ -690,7 +656,9 @@ static void selectInnerLoop( ** popping the data from the stack. */ case SRT_Coroutine: - case SRT_Callback: { + case SRT_Output: { + testcase( eDest==SRT_Coroutine ); + testcase( eDest==SRT_Output ); if( pOrderBy ){ int r1 = sqlite3GetTempReg(pParse); sqlite3VdbeAddOp3(v, OP_MakeRecord, regResult, nColumn, r1); @@ -754,8 +722,9 @@ static KeyInfo *keyInfoFromExprList(Parse *pParse, ExprList *pList){ pInfo = sqlite3DbMallocZero(db, sizeof(*pInfo) + nExpr*(sizeof(CollSeq*)+1) ); if( pInfo ){ pInfo->aSortOrder = (u8*)&pInfo->aColl[nExpr]; - pInfo->nField = nExpr; + pInfo->nField = (u16)nExpr; pInfo->enc = ENC(db); + pInfo->db = db; for(i=0, pItem=pList->a; i<nExpr; i++, pItem++){ CollSeq *pColl; pColl = sqlite3ExprCollSeq(pParse, pItem->pExpr); @@ -783,8 +752,8 @@ static void generateSortTail( int nColumn, /* Number of columns of data */ SelectDest *pDest /* Write the sorted results here */ ){ - int brk = sqlite3VdbeMakeLabel(v); - int cont = sqlite3VdbeMakeLabel(v); + int addrBreak = sqlite3VdbeMakeLabel(v); /* Jump here to exit loop */ + int addrContinue = sqlite3VdbeMakeLabel(v); /* Jump here for next cycle */ int addr; int iTab; int pseudoTab = 0; @@ -797,19 +766,22 @@ static void generateSortTail( int regRowid; iTab = pOrderBy->iECursor; - if( eDest==SRT_Callback || eDest==SRT_Coroutine ){ + regRow = sqlite3GetTempReg(pParse); + if( eDest==SRT_Output || eDest==SRT_Coroutine ){ pseudoTab = pParse->nTab++; - sqlite3VdbeAddOp2(v, OP_SetNumColumns, 0, nColumn); - sqlite3VdbeAddOp2(v, OP_OpenPseudo, pseudoTab, eDest==SRT_Callback); + sqlite3VdbeAddOp3(v, OP_OpenPseudo, pseudoTab, regRow, nColumn); + regRowid = 0; + }else{ + regRowid = sqlite3GetTempReg(pParse); } - addr = 1 + sqlite3VdbeAddOp2(v, OP_Sort, iTab, brk); - codeOffset(v, p, cont); - regRow = sqlite3GetTempReg(pParse); - regRowid = sqlite3GetTempReg(pParse); + addr = 1 + sqlite3VdbeAddOp2(v, OP_Sort, iTab, addrBreak); + codeOffset(v, p, addrContinue); sqlite3VdbeAddOp3(v, OP_Column, iTab, pOrderBy->nExpr + 1, regRow); switch( eDest ){ case SRT_Table: case SRT_EphemTab: { + testcase( eDest==SRT_Table ); + testcase( eDest==SRT_EphemTab ); sqlite3VdbeAddOp2(v, OP_NewRowid, iParm, regRowid); sqlite3VdbeAddOp3(v, OP_Insert, iParm, regRow, regRowid); sqlite3VdbeChangeP5(v, OPFLAG_APPEND); @@ -830,16 +802,19 @@ static void generateSortTail( break; } #endif - case SRT_Callback: - case SRT_Coroutine: { + default: { int i; - sqlite3VdbeAddOp2(v, OP_Integer, 1, regRowid); - sqlite3VdbeAddOp3(v, OP_Insert, pseudoTab, regRow, regRowid); + assert( eDest==SRT_Output || eDest==SRT_Coroutine ); + testcase( eDest==SRT_Output ); + testcase( eDest==SRT_Coroutine ); for(i=0; i<nColumn; i++){ assert( regRow!=pDest->iMem+i ); sqlite3VdbeAddOp3(v, OP_Column, pseudoTab, i, pDest->iMem+i); + if( i==0 ){ + sqlite3VdbeChangeP5(v, OPFLAG_CLEARCACHE); + } } - if( eDest==SRT_Callback ){ + if( eDest==SRT_Output ){ sqlite3VdbeAddOp2(v, OP_ResultRow, pDest->iMem, nColumn); sqlite3ExprCacheAffinityChange(pParse, pDest->iMem, nColumn); }else{ @@ -847,10 +822,6 @@ static void generateSortTail( } break; } - default: { - /* Do nothing */ - break; - } } sqlite3ReleaseTempReg(pParse, regRow); sqlite3ReleaseTempReg(pParse, regRowid); @@ -861,13 +832,12 @@ static void generateSortTail( /* The bottom of the loop */ - sqlite3VdbeResolveLabel(v, cont); + sqlite3VdbeResolveLabel(v, addrContinue); sqlite3VdbeAddOp2(v, OP_Next, iTab, addr); - sqlite3VdbeResolveLabel(v, brk); - if( eDest==SRT_Callback || eDest==SRT_Coroutine ){ + sqlite3VdbeResolveLabel(v, addrBreak); + if( eDest==SRT_Output || eDest==SRT_Coroutine ){ sqlite3VdbeAddOp2(v, OP_Close, pseudoTab, 0); } - } /* @@ -900,7 +870,7 @@ static const char *columnType( char const *zOriginTab = 0; char const *zOriginCol = 0; int j; - if( pExpr==0 || pNC->pSrcList==0 ) return 0; + if( NEVER(pExpr==0) || pNC->pSrcList==0 ) return 0; switch( pExpr->op ){ case TK_AGG_COLUMN: @@ -912,6 +882,8 @@ static const char *columnType( Table *pTab = 0; /* Table structure column is extracted from */ Select *pS = 0; /* Select the column is extracted from */ int iCol = pExpr->iColumn; /* Index of column in pTab */ + testcase( pExpr->op==TK_AGG_COLUMN ); + testcase( pExpr->op==TK_COLUMN ); while( pNC && !pTab ){ SrcList *pTabList = pNC->pSrcList; for(j=0;j<pTabList->nSrc && pTabList->a[j].iCursor!=pExpr->iTable;j++); @@ -924,27 +896,33 @@ static const char *columnType( } if( pTab==0 ){ - /* FIX ME: - ** This can occurs if you have something like "SELECT new.x;" inside - ** a trigger. In other words, if you reference the special "new" - ** table in the result set of a select. We do not have a good way - ** to find the actual table type, so call it "TEXT". This is really - ** something of a bug, but I do not know how to fix it. + /* At one time, code such as "SELECT new.x" within a trigger would + ** cause this condition to run. Since then, we have restructured how + ** trigger code is generated and so this condition is no longer + ** possible. However, it can still be true for statements like + ** the following: ** - ** This code does not produce the correct answer - it just prevents - ** a segfault. See ticket #1229. - */ - zType = "TEXT"; + ** CREATE TABLE t1(col INTEGER); + ** SELECT (SELECT t1.col) FROM FROM t1; + ** + ** when columnType() is called on the expression "t1.col" in the + ** sub-select. In this case, set the column type to NULL, even + ** though it should really be "INTEGER". + ** + ** This is not a problem, as the column type of "t1.col" is never + ** used. When columnType() is called on the expression + ** "(SELECT t1.col)", the correct type is returned (see the TK_SELECT + ** branch below. */ break; } - assert( pTab ); + assert( pTab && pExpr->pTab==pTab ); if( pS ){ /* The "table" is actually a sub-select or a view in the FROM clause ** of the SELECT statement. Return the declaration type and origin ** data for the result-set column of the sub-select. */ - if( iCol>=0 && iCol<pS->pEList->nExpr ){ + if( ALWAYS(iCol>=0 && iCol<pS->pEList->nExpr) ){ /* If iCol is less than zero, then the expression requests the ** rowid of the sub-select or view. This expression is legal (see ** test case misc2.2.2) - it always evaluates to NULL. @@ -952,11 +930,11 @@ static const char *columnType( NameContext sNC; Expr *p = pS->pEList->a[iCol].pExpr; sNC.pSrcList = pS->pSrc; - sNC.pNext = 0; + sNC.pNext = pNC; sNC.pParse = pNC->pParse; zType = columnType(&sNC, p, &zOriginDb, &zOriginTab, &zOriginCol); } - }else if( pTab->pSchema ){ + }else if( ALWAYS(pTab->pSchema) ){ /* A real table */ assert( !pS ); if( iCol<0 ) iCol = pTab->iPKey; @@ -983,8 +961,9 @@ static const char *columnType( ** statement. */ NameContext sNC; - Select *pS = pExpr->pSelect; + Select *pS = pExpr->x.pSelect; Expr *p = pS->pEList->a[0].pExpr; + assert( ExprHasProperty(pExpr, EP_xIsSelect) ); sNC.pSrcList = pS->pSrc; sNC.pNext = pNC; sNC.pParse = pNC->pParse; @@ -1031,13 +1010,13 @@ static void generateColumnTypes( ** column specific strings, in case the schema is reset before this ** virtual machine is deleted. */ - sqlite3VdbeSetColName(v, i, COLNAME_DATABASE, zOrigDb, P4_TRANSIENT); - sqlite3VdbeSetColName(v, i, COLNAME_TABLE, zOrigTab, P4_TRANSIENT); - sqlite3VdbeSetColName(v, i, COLNAME_COLUMN, zOrigCol, P4_TRANSIENT); + sqlite3VdbeSetColName(v, i, COLNAME_DATABASE, zOrigDb, SQLITE_TRANSIENT); + sqlite3VdbeSetColName(v, i, COLNAME_TABLE, zOrigTab, SQLITE_TRANSIENT); + sqlite3VdbeSetColName(v, i, COLNAME_COLUMN, zOrigCol, SQLITE_TRANSIENT); #else zType = columnType(&sNC, p, 0, 0, 0); #endif - sqlite3VdbeSetColName(v, i, COLNAME_DECLTYPE, zType, P4_TRANSIENT); + sqlite3VdbeSetColName(v, i, COLNAME_DECLTYPE, zType, SQLITE_TRANSIENT); } #endif /* SQLITE_OMIT_DECLTYPE */ } @@ -1064,8 +1043,7 @@ static void generateColumnNames( } #endif - assert( v!=0 ); - if( pParse->colNamesSet || v==0 || db->mallocFailed ) return; + if( pParse->colNamesSet || NEVER(v==0) || db->mallocFailed ) return; pParse->colNamesSet = 1; fullNames = (db->flags & SQLITE_FullColNames)!=0; shortNames = (db->flags & SQLITE_ShortColNames)!=0; @@ -1073,15 +1051,17 @@ static void generateColumnNames( for(i=0; i<pEList->nExpr; i++){ Expr *p; p = pEList->a[i].pExpr; - if( p==0 ) continue; + if( NEVER(p==0) ) continue; if( pEList->a[i].zName ){ char *zName = pEList->a[i].zName; - sqlite3VdbeSetColName(v, i, COLNAME_NAME, zName, strlen(zName)); - }else if( p->op==TK_COLUMN && pTabList ){ + sqlite3VdbeSetColName(v, i, COLNAME_NAME, zName, SQLITE_TRANSIENT); + }else if( (p->op==TK_COLUMN || p->op==TK_AGG_COLUMN) && pTabList ){ Table *pTab; char *zCol; int iCol = p->iColumn; - for(j=0; j<pTabList->nSrc && pTabList->a[j].iCursor!=p->iTable; j++){} + for(j=0; ALWAYS(j<pTabList->nSrc); j++){ + if( pTabList->a[j].iCursor==p->iTable ) break; + } assert( j<pTabList->nSrc ); pTab = pTabList->a[j].pTab; if( iCol<0 ) iCol = pTab->iPKey; @@ -1092,20 +1072,18 @@ static void generateColumnNames( zCol = pTab->aCol[iCol].zName; } if( !shortNames && !fullNames ){ - sqlite3VdbeSetColName(v, i, COLNAME_NAME, (char*)p->span.z, p->span.n); - }else if( fullNames || (!shortNames && pTabList->nSrc>1) ){ + sqlite3VdbeSetColName(v, i, COLNAME_NAME, + sqlite3DbStrDup(db, pEList->a[i].zSpan), SQLITE_DYNAMIC); + }else if( fullNames ){ char *zName = 0; - char *zTab; - - zTab = pTabList->a[j].zAlias; - if( fullNames || zTab==0 ) zTab = pTab->zName; - zName = sqlite3MPrintf(db, "%s.%s", zTab, zCol); - sqlite3VdbeSetColName(v, i, COLNAME_NAME, zName, P4_DYNAMIC); + zName = sqlite3MPrintf(db, "%s.%s", pTab->zName, zCol); + sqlite3VdbeSetColName(v, i, COLNAME_NAME, zName, SQLITE_DYNAMIC); }else{ - sqlite3VdbeSetColName(v, i, COLNAME_NAME, zCol, strlen(zCol)); + sqlite3VdbeSetColName(v, i, COLNAME_NAME, zCol, SQLITE_TRANSIENT); } }else{ - sqlite3VdbeSetColName(v, i, COLNAME_NAME, (char*)p->span.z, p->span.n); + sqlite3VdbeSetColName(v, i, COLNAME_NAME, + sqlite3DbStrDup(db, pEList->a[i].zSpan), SQLITE_DYNAMIC); } } generateColumnTypes(pParse, pTabList, pEList); @@ -1128,84 +1106,73 @@ static const char *selectOpName(int id){ #endif /* SQLITE_OMIT_COMPOUND_SELECT */ /* -** Forward declaration -*/ -static int prepSelectStmt(Parse*, Select*); - -/* -** Given a SELECT statement, generate a Table structure that describes -** the result set of that SELECT. +** Given a an expression list (which is really the list of expressions +** that form the result set of a SELECT statement) compute appropriate +** column names for a table that would hold the expression list. +** +** All column names will be unique. +** +** Only the column names are computed. Column.zType, Column.zColl, +** and other fields of Column are zeroed. +** +** Return SQLITE_OK on success. If a memory allocation error occurs, +** store NULL in *paCol and 0 in *pnCol and return SQLITE_NOMEM. */ -Table *sqlite3ResultSetOfSelect(Parse *pParse, char *zTabName, Select *pSelect){ - Table *pTab; - int i, j, rc; - ExprList *pEList; - Column *aCol, *pCol; - sqlite3 *db = pParse->db; - int savedFlags; - - savedFlags = db->flags; - db->flags &= ~SQLITE_FullColNames; - db->flags |= SQLITE_ShortColNames; - rc = sqlite3SelectResolve(pParse, pSelect, 0); - if( rc==SQLITE_OK ){ - while( pSelect->pPrior ) pSelect = pSelect->pPrior; - rc = prepSelectStmt(pParse, pSelect); - if( rc==SQLITE_OK ){ - rc = sqlite3SelectResolve(pParse, pSelect, 0); - } - } - db->flags = savedFlags; - if( rc ){ - return 0; - } - pTab = sqlite3DbMallocZero(db, sizeof(Table) ); - if( pTab==0 ){ - return 0; - } - pTab->db = db; - pTab->nRef = 1; - pTab->zName = zTabName ? sqlite3DbStrDup(db, zTabName) : 0; - pEList = pSelect->pEList; - pTab->nCol = pEList->nExpr; - assert( pTab->nCol>0 ); - pTab->aCol = aCol = sqlite3DbMallocZero(db, sizeof(pTab->aCol[0])*pTab->nCol); - testcase( aCol==0 ); - for(i=0, pCol=aCol; i<pTab->nCol; i++, pCol++){ - Expr *p; - char *zType; - char *zName; - int nName; - CollSeq *pColl; - int cnt; - NameContext sNC; - +static int selectColumnsFromExprList( + Parse *pParse, /* Parsing context */ + ExprList *pEList, /* Expr list from which to derive column names */ + int *pnCol, /* Write the number of columns here */ + Column **paCol /* Write the new column list here */ +){ + sqlite3 *db = pParse->db; /* Database connection */ + int i, j; /* Loop counters */ + int cnt; /* Index added to make the name unique */ + Column *aCol, *pCol; /* For looping over result columns */ + int nCol; /* Number of columns in the result set */ + Expr *p; /* Expression for a single result column */ + char *zName; /* Column name */ + int nName; /* Size of name in zName[] */ + + *pnCol = nCol = pEList->nExpr; + aCol = *paCol = sqlite3DbMallocZero(db, sizeof(aCol[0])*nCol); + if( aCol==0 ) return SQLITE_NOMEM; + for(i=0, pCol=aCol; i<nCol; i++, pCol++){ /* Get an appropriate name for the column */ p = pEList->a[i].pExpr; - assert( p->pRight==0 || p->pRight->token.z==0 || p->pRight->token.z[0]!=0 ); + assert( p->pRight==0 || ExprHasProperty(p->pRight, EP_IntValue) + || p->pRight->u.zToken==0 || p->pRight->u.zToken[0]!=0 ); if( (zName = pEList->a[i].zName)!=0 ){ /* If the column contains an "AS <name>" phrase, use <name> as the name */ zName = sqlite3DbStrDup(db, zName); - }else if( p->op==TK_COLUMN && p->pTab ){ - /* For columns use the column name name */ - int iCol = p->iColumn; - if( iCol<0 ) iCol = p->pTab->iPKey; - zName = sqlite3MPrintf(db, "%s", p->pTab->aCol[iCol].zName); }else{ - /* Use the original text of the column expression as its name */ - zName = sqlite3MPrintf(db, "%T", &p->span); + Expr *pColExpr = p; /* The expression that is the result column name */ + Table *pTab; /* Table associated with this expression */ + while( pColExpr->op==TK_DOT ) pColExpr = pColExpr->pRight; + if( pColExpr->op==TK_COLUMN && ALWAYS(pColExpr->pTab!=0) ){ + /* For columns use the column name name */ + int iCol = pColExpr->iColumn; + pTab = pColExpr->pTab; + if( iCol<0 ) iCol = pTab->iPKey; + zName = sqlite3MPrintf(db, "%s", + iCol>=0 ? pTab->aCol[iCol].zName : "rowid"); + }else if( pColExpr->op==TK_ID ){ + assert( !ExprHasProperty(pColExpr, EP_IntValue) ); + zName = sqlite3MPrintf(db, "%s", pColExpr->u.zToken); + }else{ + /* Use the original text of the column expression as its name */ + zName = sqlite3MPrintf(db, "%s", pEList->a[i].zSpan); + } } if( db->mallocFailed ){ sqlite3DbFree(db, zName); break; } - sqlite3Dequote(zName); /* Make sure the column name is unique. If the name is not unique, ** append a integer to the name so that it becomes unique. */ - nName = strlen(zName); + nName = sqlite3Strlen30(zName); for(j=cnt=0; j<i; j++){ if( sqlite3StrICmp(aCol[j].zName, zName)==0 ){ char *zNewName; @@ -1218,518 +1185,97 @@ Table *sqlite3ResultSetOfSelect(Parse *pParse, char *zTabName, Select *pSelect){ } } pCol->zName = zName; - - /* Get the typename, type affinity, and collating sequence for the - ** column. - */ - memset(&sNC, 0, sizeof(sNC)); - sNC.pSrcList = pSelect->pSrc; - zType = sqlite3DbStrDup(db, columnType(&sNC, p, 0, 0, 0)); - pCol->zType = zType; - pCol->affinity = sqlite3ExprAffinity(p); - pColl = sqlite3ExprCollSeq(pParse, p); - if( pColl ){ - pCol->zColl = sqlite3DbStrDup(db, pColl->zName); - } } - pTab->iPKey = -1; if( db->mallocFailed ){ - sqlite3DeleteTable(pTab); - return 0; - } - return pTab; -} - -/* -** Prepare a SELECT statement for processing by doing the following -** things: -** -** (1) Make sure VDBE cursor numbers have been assigned to every -** element of the FROM clause. -** -** (2) Fill in the pTabList->a[].pTab fields in the SrcList that -** defines FROM clause. When views appear in the FROM clause, -** fill pTabList->a[].pSelect with a copy of the SELECT statement -** that implements the view. A copy is made of the view's SELECT -** statement so that we can freely modify or delete that statement -** without worrying about messing up the presistent representation -** of the view. -** -** (3) Add terms to the WHERE clause to accomodate the NATURAL keyword -** on joins and the ON and USING clause of joins. -** -** (4) Scan the list of columns in the result set (pEList) looking -** for instances of the "*" operator or the TABLE.* operator. -** If found, expand each "*" to be every column in every table -** and TABLE.* to be every column in TABLE. -** -** Return 0 on success. If there are problems, leave an error message -** in pParse and return non-zero. -*/ -static int prepSelectStmt(Parse *pParse, Select *p){ - int i, j, k, rc; - SrcList *pTabList; - ExprList *pEList; - struct SrcList_item *pFrom; - sqlite3 *db = pParse->db; - - if( p==0 || p->pSrc==0 || db->mallocFailed ){ - return 1; - } - pTabList = p->pSrc; - pEList = p->pEList; - - /* Make sure cursor numbers have been assigned to all entries in - ** the FROM clause of the SELECT statement. - */ - sqlite3SrcListAssignCursors(pParse, p->pSrc); - - /* Look up every table named in the FROM clause of the select. If - ** an entry of the FROM clause is a subquery instead of a table or view, - ** then create a transient table structure to describe the subquery. - */ - for(i=0, pFrom=pTabList->a; i<pTabList->nSrc; i++, pFrom++){ - Table *pTab; - if( pFrom->pTab!=0 ){ - /* This statement has already been prepared. There is no need - ** to go further. */ - assert( i==0 ); - return 0; - } - if( pFrom->zName==0 ){ -#ifndef SQLITE_OMIT_SUBQUERY - /* A sub-query in the FROM clause of a SELECT */ - assert( pFrom->pSelect!=0 ); - if( pFrom->zAlias==0 ){ - pFrom->zAlias = - sqlite3MPrintf(db, "sqlite_subquery_%p_", (void*)pFrom->pSelect); - } - assert( pFrom->pTab==0 ); - pFrom->pTab = pTab = - sqlite3ResultSetOfSelect(pParse, pFrom->zAlias, pFrom->pSelect); - if( pTab==0 ){ - return 1; - } - /* The isEphem flag indicates that the Table structure has been - ** dynamically allocated and may be freed at any time. In other words, - ** pTab is not pointing to a persistent table structure that defines - ** part of the schema. */ - pTab->isEphem = 1; -#endif - }else{ - /* An ordinary table or view name in the FROM clause */ - assert( pFrom->pTab==0 ); - pFrom->pTab = pTab = - sqlite3LocateTable(pParse,0,pFrom->zName,pFrom->zDatabase); - if( pTab==0 ){ - return 1; - } - pTab->nRef++; -#if !defined(SQLITE_OMIT_VIEW) || !defined (SQLITE_OMIT_VIRTUALTABLE) - if( pTab->pSelect || IsVirtual(pTab) ){ - /* We reach here if the named table is a really a view */ - if( sqlite3ViewGetColumnNames(pParse, pTab) ){ - return 1; - } - /* If pFrom->pSelect!=0 it means we are dealing with a - ** view within a view. The SELECT structure has already been - ** copied by the outer view so we can skip the copy step here - ** in the inner view. - */ - if( pFrom->pSelect==0 ){ - pFrom->pSelect = sqlite3SelectDup(db, pTab->pSelect); - } - } -#endif - } - } - - /* Process NATURAL keywords, and ON and USING clauses of joins. - */ - if( sqliteProcessJoin(pParse, p) ) return 1; - - /* For every "*" that occurs in the column list, insert the names of - ** all columns in all tables. And for every TABLE.* insert the names - ** of all columns in TABLE. The parser inserted a special expression - ** with the TK_ALL operator for each "*" that it found in the column list. - ** The following code just has to locate the TK_ALL expressions and expand - ** each one to the list of all columns in all tables. - ** - ** The first loop just checks to see if there are any "*" operators - ** that need expanding. - */ - for(k=0; k<pEList->nExpr; k++){ - Expr *pE = pEList->a[k].pExpr; - if( pE->op==TK_ALL ) break; - if( pE->op==TK_DOT && pE->pRight && pE->pRight->op==TK_ALL - && pE->pLeft && pE->pLeft->op==TK_ID ) break; - } - rc = 0; - if( k<pEList->nExpr ){ - /* - ** If we get here it means the result set contains one or more "*" - ** operators that need to be expanded. Loop through each expression - ** in the result set and expand them one by one. - */ - struct ExprList_item *a = pEList->a; - ExprList *pNew = 0; - int flags = pParse->db->flags; - int longNames = (flags & SQLITE_FullColNames)!=0 - && (flags & SQLITE_ShortColNames)==0; - - for(k=0; k<pEList->nExpr; k++){ - Expr *pE = a[k].pExpr; - if( pE->op!=TK_ALL && - (pE->op!=TK_DOT || pE->pRight==0 || pE->pRight->op!=TK_ALL) ){ - /* This particular expression does not need to be expanded. - */ - pNew = sqlite3ExprListAppend(pParse, pNew, a[k].pExpr, 0); - if( pNew ){ - pNew->a[pNew->nExpr-1].zName = a[k].zName; - }else{ - rc = 1; - } - a[k].pExpr = 0; - a[k].zName = 0; - }else{ - /* This expression is a "*" or a "TABLE.*" and needs to be - ** expanded. */ - int tableSeen = 0; /* Set to 1 when TABLE matches */ - char *zTName; /* text of name of TABLE */ - if( pE->op==TK_DOT && pE->pLeft ){ - zTName = sqlite3NameFromToken(db, &pE->pLeft->token); - }else{ - zTName = 0; - } - for(i=0, pFrom=pTabList->a; i<pTabList->nSrc; i++, pFrom++){ - Table *pTab = pFrom->pTab; - char *zTabName = pFrom->zAlias; - if( zTabName==0 || zTabName[0]==0 ){ - zTabName = pTab->zName; - } - assert( zTabName ); - if( zTName && sqlite3StrICmp(zTName, zTabName)!=0 ){ - continue; - } - tableSeen = 1; - for(j=0; j<pTab->nCol; j++){ - Expr *pExpr, *pRight; - char *zName = pTab->aCol[j].zName; - - /* If a column is marked as 'hidden' (currently only possible - ** for virtual tables), do not include it in the expanded - ** result-set list. - */ - if( IsHiddenColumn(&pTab->aCol[j]) ){ - assert(IsVirtual(pTab)); - continue; - } - - if( i>0 ){ - struct SrcList_item *pLeft = &pTabList->a[i-1]; - if( (pLeft[1].jointype & JT_NATURAL)!=0 && - columnIndex(pLeft->pTab, zName)>=0 ){ - /* In a NATURAL join, omit the join columns from the - ** table on the right */ - continue; - } - if( sqlite3IdListIndex(pLeft[1].pUsing, zName)>=0 ){ - /* In a join with a USING clause, omit columns in the - ** using clause from the table on the right. */ - continue; - } - } - pRight = sqlite3PExpr(pParse, TK_ID, 0, 0, 0); - if( pRight==0 ) break; - setQuotedToken(pParse, &pRight->token, zName); - if( longNames || pTabList->nSrc>1 ){ - Expr *pLeft = sqlite3PExpr(pParse, TK_ID, 0, 0, 0); - pExpr = sqlite3PExpr(pParse, TK_DOT, pLeft, pRight, 0); - if( pExpr==0 ) break; - setQuotedToken(pParse, &pLeft->token, zTabName); -#if 1 - setToken(&pExpr->span, - sqlite3MPrintf(db, "%s.%s", zTabName, zName)); - pExpr->span.dyn = 1; -#else - pExpr->span = pRight->token; - pExpr->span.dyn = 0; -#endif - pExpr->token.z = 0; - pExpr->token.n = 0; - pExpr->token.dyn = 0; - }else{ - pExpr = pRight; - pExpr->span = pExpr->token; - pExpr->span.dyn = 0; - } - if( longNames ){ - pNew = sqlite3ExprListAppend(pParse, pNew, pExpr, &pExpr->span); - }else{ - pNew = sqlite3ExprListAppend(pParse, pNew, pExpr, &pRight->token); - } - } - } - if( !tableSeen ){ - if( zTName ){ - sqlite3ErrorMsg(pParse, "no such table: %s", zTName); - }else{ - sqlite3ErrorMsg(pParse, "no tables specified"); - } - rc = 1; - } - sqlite3DbFree(db, zTName); - } + for(j=0; j<i; j++){ + sqlite3DbFree(db, aCol[j].zName); } - sqlite3ExprListDelete(db, pEList); - p->pEList = pNew; - } -#if SQLITE_MAX_COLUMN - if( p->pEList && p->pEList->nExpr>db->aLimit[SQLITE_LIMIT_COLUMN] ){ - sqlite3ErrorMsg(pParse, "too many columns in result set"); - rc = SQLITE_ERROR; - } -#endif - if( db->mallocFailed ){ - rc = SQLITE_NOMEM; + sqlite3DbFree(db, aCol); + *paCol = 0; + *pnCol = 0; + return SQLITE_NOMEM; } - return rc; + return SQLITE_OK; } /* -** pE is a pointer to an expression which is a single term in -** ORDER BY or GROUP BY clause. -** -** At the point this routine is called, we already know that the -** ORDER BY term is not an integer index into the result set. That -** casee is handled by the calling routine. -** -** If pE is a well-formed expression and the SELECT statement -** is not compound, then return 0. This indicates to the -** caller that it should sort by the value of the ORDER BY -** expression. +** Add type and collation information to a column list based on +** a SELECT statement. +** +** The column list presumably came from selectColumnNamesFromExprList(). +** The column list has only names, not types or collations. This +** routine goes through and adds the types and collations. ** -** If the SELECT is compound, then attempt to match pE against -** result set columns in the left-most SELECT statement. Return -** the index i of the matching column, as an indication to the -** caller that it should sort by the i-th column. If there is -** no match, return -1 and leave an error message in pParse. +** This routine requires that all identifiers in the SELECT +** statement be resolved. */ -static int matchOrderByTermToExprList( - Parse *pParse, /* Parsing context for error messages */ - Select *pSelect, /* The SELECT statement with the ORDER BY clause */ - Expr *pE, /* The specific ORDER BY term */ - int idx, /* When ORDER BY term is this */ - int isCompound, /* True if this is a compound SELECT */ - u8 *pHasAgg /* True if expression contains aggregate functions */ +static void selectAddColumnTypeAndCollation( + Parse *pParse, /* Parsing contexts */ + int nCol, /* Number of columns */ + Column *aCol, /* List of columns */ + Select *pSelect /* SELECT used to determine types and collations */ ){ - int i; /* Loop counter */ - ExprList *pEList; /* The columns of the result set */ - NameContext nc; /* Name context for resolving pE */ - - assert( sqlite3ExprIsInteger(pE, &i)==0 ); - pEList = pSelect->pEList; - - /* If the term is a simple identifier that try to match that identifier - ** against a column name in the result set. - */ - if( pE->op==TK_ID || (pE->op==TK_STRING && pE->token.z[0]!='\'') ){ - sqlite3 *db = pParse->db; - char *zCol = sqlite3NameFromToken(db, &pE->token); - if( zCol==0 ){ - return -1; - } - for(i=0; i<pEList->nExpr; i++){ - char *zAs = pEList->a[i].zName; - if( zAs!=0 && sqlite3StrICmp(zAs, zCol)==0 ){ - sqlite3DbFree(db, zCol); - return i+1; - } - } - sqlite3DbFree(db, zCol); - } - - /* Resolve all names in the ORDER BY term expression - */ - memset(&nc, 0, sizeof(nc)); - nc.pParse = pParse; - nc.pSrcList = pSelect->pSrc; - nc.pEList = pEList; - nc.allowAgg = 1; - nc.nErr = 0; - if( sqlite3ExprResolveNames(&nc, pE) ){ - if( isCompound ){ - sqlite3ErrorClear(pParse); - return 0; - }else{ - return -1; - } - } - if( nc.hasAgg && pHasAgg ){ - *pHasAgg = 1; - } + sqlite3 *db = pParse->db; + NameContext sNC; + Column *pCol; + CollSeq *pColl; + int i; + Expr *p; + struct ExprList_item *a; - /* For a compound SELECT, we need to try to match the ORDER BY - ** expression against an expression in the result set - */ - if( isCompound ){ - for(i=0; i<pEList->nExpr; i++){ - if( sqlite3ExprCompare(pEList->a[i].pExpr, pE) ){ - return i+1; - } + assert( pSelect!=0 ); + assert( (pSelect->selFlags & SF_Resolved)!=0 ); + assert( nCol==pSelect->pEList->nExpr || db->mallocFailed ); + if( db->mallocFailed ) return; + memset(&sNC, 0, sizeof(sNC)); + sNC.pSrcList = pSelect->pSrc; + a = pSelect->pEList->a; + for(i=0, pCol=aCol; i<nCol; i++, pCol++){ + p = a[i].pExpr; + pCol->zType = sqlite3DbStrDup(db, columnType(&sNC, p, 0, 0, 0)); + pCol->affinity = sqlite3ExprAffinity(p); + if( pCol->affinity==0 ) pCol->affinity = SQLITE_AFF_NONE; + pColl = sqlite3ExprCollSeq(pParse, p); + if( pColl ){ + pCol->zColl = sqlite3DbStrDup(db, pColl->zName); } } - return 0; } - /* -** Analyze and ORDER BY or GROUP BY clause in a simple SELECT statement. -** Return the number of errors seen. -** -** Every term of the ORDER BY or GROUP BY clause needs to be an -** expression. If any expression is an integer constant, then -** that expression is replaced by the corresponding -** expression from the result set. +** Given a SELECT statement, generate a Table structure that describes +** the result set of that SELECT. */ -static int processOrderGroupBy( - Parse *pParse, /* Parsing context. Leave error messages here */ - Select *pSelect, /* The SELECT statement containing the clause */ - ExprList *pOrderBy, /* The ORDER BY or GROUP BY clause to be processed */ - int isOrder, /* 1 for ORDER BY. 0 for GROUP BY */ - u8 *pHasAgg /* Set to TRUE if any term contains an aggregate */ -){ - int i; +Table *sqlite3ResultSetOfSelect(Parse *pParse, Select *pSelect){ + Table *pTab; sqlite3 *db = pParse->db; - ExprList *pEList; + int savedFlags; - if( pOrderBy==0 || pParse->db->mallocFailed ) return 0; -#if SQLITE_MAX_COLUMN - if( pOrderBy->nExpr>db->aLimit[SQLITE_LIMIT_COLUMN] ){ - const char *zType = isOrder ? "ORDER" : "GROUP"; - sqlite3ErrorMsg(pParse, "too many terms in %s BY clause", zType); - return 1; - } -#endif - pEList = pSelect->pEList; - if( pEList==0 ){ + savedFlags = db->flags; + db->flags &= ~SQLITE_FullColNames; + db->flags |= SQLITE_ShortColNames; + sqlite3SelectPrep(pParse, pSelect, 0); + if( pParse->nErr ) return 0; + while( pSelect->pPrior ) pSelect = pSelect->pPrior; + db->flags = savedFlags; + pTab = sqlite3DbMallocZero(db, sizeof(Table) ); + if( pTab==0 ){ return 0; } - for(i=0; i<pOrderBy->nExpr; i++){ - int iCol; - Expr *pE = pOrderBy->a[i].pExpr; - if( sqlite3ExprIsInteger(pE, &iCol) ){ - if( iCol<=0 || iCol>pEList->nExpr ){ - const char *zType = isOrder ? "ORDER" : "GROUP"; - sqlite3ErrorMsg(pParse, - "%r %s BY term out of range - should be " - "between 1 and %d", i+1, zType, pEList->nExpr); - return 1; - } - }else{ - iCol = matchOrderByTermToExprList(pParse, pSelect, pE, i+1, 0, pHasAgg); - if( iCol<0 ){ - return 1; - } - } - if( iCol>0 ){ - CollSeq *pColl = pE->pColl; - int flags = pE->flags & EP_ExpCollate; - sqlite3ExprDelete(db, pE); - pE = sqlite3ExprDup(db, pEList->a[iCol-1].pExpr); - pOrderBy->a[i].pExpr = pE; - if( pE && pColl && flags ){ - pE->pColl = pColl; - pE->flags |= flags; - } - } - } - return 0; -} - -/* -** Analyze and ORDER BY or GROUP BY clause in a SELECT statement. Return -** the number of errors seen. -** -** If iTable>0 then make the N-th term of the ORDER BY clause refer to -** the N-th column of table iTable. -** -** If iTable==0 then transform each term of the ORDER BY clause to refer -** to a column of the result set by number. -*/ -static int processCompoundOrderBy( - Parse *pParse, /* Parsing context. Leave error messages here */ - Select *pSelect /* The SELECT statement containing the ORDER BY */ -){ - int i; - ExprList *pOrderBy; - ExprList *pEList; - sqlite3 *db; - int moreToDo = 1; - - pOrderBy = pSelect->pOrderBy; - if( pOrderBy==0 ) return 0; - db = pParse->db; -#if SQLITE_MAX_COLUMN - if( pOrderBy->nExpr>db->aLimit[SQLITE_LIMIT_COLUMN] ){ - sqlite3ErrorMsg(pParse, "too many terms in ORDER BY clause"); - return 1; - } -#endif - for(i=0; i<pOrderBy->nExpr; i++){ - pOrderBy->a[i].done = 0; - } - while( pSelect->pPrior ){ - pSelect = pSelect->pPrior; - } - while( pSelect && moreToDo ){ - moreToDo = 0; - pEList = pSelect->pEList; - if( pEList==0 ){ - return 1; - } - for(i=0; i<pOrderBy->nExpr; i++){ - int iCol = -1; - Expr *pE, *pDup; - if( pOrderBy->a[i].done ) continue; - pE = pOrderBy->a[i].pExpr; - if( sqlite3ExprIsInteger(pE, &iCol) ){ - if( iCol<0 || iCol>pEList->nExpr ){ - sqlite3ErrorMsg(pParse, - "%r ORDER BY term out of range - should be " - "between 1 and %d", i+1, pEList->nExpr); - return 1; - } - }else{ - pDup = sqlite3ExprDup(db, pE); - if( !db->mallocFailed ){ - assert(pDup); - iCol = matchOrderByTermToExprList(pParse, pSelect, pDup, i+1, 1, 0); - } - sqlite3ExprDelete(db, pDup); - if( iCol<0 ){ - return 1; - } - } - if( iCol>0 ){ - pE->op = TK_INTEGER; - pE->flags |= EP_IntValue; - pE->iTable = iCol; - pOrderBy->a[i].done = 1; - }else{ - moreToDo = 1; - } - } - pSelect = pSelect->pNext; - } - for(i=0; i<pOrderBy->nExpr; i++){ - if( pOrderBy->a[i].done==0 ){ - sqlite3ErrorMsg(pParse, "%r ORDER BY term does not match any " - "column in the result set", i+1); - return 1; - } + /* The sqlite3ResultSetOfSelect() is only used n contexts where lookaside + ** is disabled, so we might as well hard-code pTab->dbMem to NULL. */ + assert( db->lookaside.bEnabled==0 ); + pTab->dbMem = 0; + pTab->nRef = 1; + pTab->zName = 0; + selectColumnsFromExprList(pParse, pSelect->pEList, &pTab->nCol, &pTab->aCol); + selectAddColumnTypeAndCollation(pParse, pTab->nCol, pTab->aCol, pSelect); + pTab->iPKey = -1; + if( db->mallocFailed ){ + sqlite3DeleteTable(pTab); + return 0; } - return 0; + return pTab; } /* @@ -1781,29 +1327,25 @@ static void computeLimitRegisters(Parse *pParse, Select *p, int iBreak){ ** The current implementation interprets "LIMIT 0" to mean ** no rows. */ + sqlite3ExprCacheClear(pParse); + assert( p->pOffset==0 || p->pLimit!=0 ); if( p->pLimit ){ p->iLimit = iLimit = ++pParse->nMem; v = sqlite3GetVdbe(pParse); - if( v==0 ) return; + if( NEVER(v==0) ) return; /* VDBE should have already been allocated */ sqlite3ExprCode(pParse, p->pLimit, iLimit); sqlite3VdbeAddOp1(v, OP_MustBeInt, iLimit); VdbeComment((v, "LIMIT counter")); sqlite3VdbeAddOp2(v, OP_IfZero, iLimit, iBreak); - } - if( p->pOffset ){ - p->iOffset = iOffset = ++pParse->nMem; - if( p->pLimit ){ + if( p->pOffset ){ + p->iOffset = iOffset = ++pParse->nMem; pParse->nMem++; /* Allocate an extra register for limit+offset */ - } - v = sqlite3GetVdbe(pParse); - if( v==0 ) return; - sqlite3ExprCode(pParse, p->pOffset, iOffset); - sqlite3VdbeAddOp1(v, OP_MustBeInt, iOffset); - VdbeComment((v, "OFFSET counter")); - addr1 = sqlite3VdbeAddOp1(v, OP_IfPos, iOffset); - sqlite3VdbeAddOp2(v, OP_Integer, 0, iOffset); - sqlite3VdbeJumpHere(v, addr1); - if( p->pLimit ){ + sqlite3ExprCode(pParse, p->pOffset, iOffset); + sqlite3VdbeAddOp1(v, OP_MustBeInt, iOffset); + VdbeComment((v, "OFFSET counter")); + addr1 = sqlite3VdbeAddOp1(v, OP_IfPos, iOffset); + sqlite3VdbeAddOp2(v, OP_Integer, 0, iOffset); + sqlite3VdbeJumpHere(v, addr1); sqlite3VdbeAddOp3(v, OP_Add, iLimit, iOffset, iOffset+1); VdbeComment((v, "LIMIT+OFFSET")); addr1 = sqlite3VdbeAddOp1(v, OP_IfPos, iLimit); @@ -1829,7 +1371,8 @@ static CollSeq *multiSelectCollSeq(Parse *pParse, Select *p, int iCol){ }else{ pRet = 0; } - if( pRet==0 ){ + assert( iCol>=0 ); + if( pRet==0 && iCol<p->pEList->nExpr ){ pRet = sqlite3ExprCollSeq(pParse, p->pEList->a[iCol].pExpr); } return pRet; @@ -1896,6 +1439,7 @@ static int multiSelect( pPrior = p->pPrior; assert( pPrior->pRightmost!=pPrior ); assert( pPrior->pRightmost==p->pRightmost ); + dest = *pDest; if( pPrior->pOrderBy ){ sqlite3ErrorMsg(pParse,"ORDER BY clause should come after %s not before", selectOpName(p->op)); @@ -1914,7 +1458,6 @@ static int multiSelect( /* Create the destination temporary table if necessary */ - dest = *pDest; if( dest.eDest==SRT_EphemTab ){ assert( p->pEList ); sqlite3VdbeAddOp2(v, OP_OpenEphemeral, dest.iParm, p->pEList->nExpr); @@ -1946,7 +1489,7 @@ static int multiSelect( assert( !pPrior->pLimit ); pPrior->pLimit = p->pLimit; pPrior->pOffset = p->pOffset; - rc = sqlite3Select(pParse, pPrior, &dest, 0, 0, 0); + rc = sqlite3Select(pParse, pPrior, &dest); p->pLimit = 0; p->pOffset = 0; if( rc ){ @@ -1959,12 +1502,10 @@ static int multiSelect( addr = sqlite3VdbeAddOp1(v, OP_IfZero, p->iLimit); VdbeComment((v, "Jump ahead if LIMIT reached")); } - rc = sqlite3Select(pParse, p, &dest, 0, 0, 0); + rc = sqlite3Select(pParse, p, &dest); + testcase( rc!=SQLITE_OK ); pDelete = p->pPrior; p->pPrior = pPrior; - if( rc ){ - goto multi_select_end; - } if( addr ){ sqlite3VdbeJumpHere(v, addr); } @@ -1973,17 +1514,23 @@ static int multiSelect( case TK_EXCEPT: case TK_UNION: { int unionTab; /* Cursor number of the temporary table holding result */ - int op = 0; /* One of the SRT_ operations to apply to self */ + u8 op = 0; /* One of the SRT_ operations to apply to self */ int priorOp; /* The SRT_ operation to apply to prior selects */ Expr *pLimit, *pOffset; /* Saved values of p->nLimit and p->nOffset */ int addr; SelectDest uniondest; + testcase( p->op==TK_EXCEPT ); + testcase( p->op==TK_UNION ); priorOp = SRT_Union; - if( dest.eDest==priorOp && !p->pLimit && !p->pOffset ){ + if( dest.eDest==priorOp && ALWAYS(!p->pLimit &&!p->pOffset) ){ /* We can reuse a temporary table generated by a SELECT to our ** right. */ + assert( p->pRightmost!=p ); /* Can only happen for leftward elements + ** of a 3-way or more compound */ + assert( p->pLimit==0 ); /* Not allowed on leftward elements */ + assert( p->pOffset==0 ); /* Not allowed on leftward elements */ unionTab = dest.iParm; }else{ /* We will need to create our own temporary table to hold the @@ -1994,7 +1541,7 @@ static int multiSelect( addr = sqlite3VdbeAddOp2(v, OP_OpenEphemeral, unionTab, 0); assert( p->addrOpenEphm[0] == -1 ); p->addrOpenEphm[0] = addr; - p->pRightmost->usesEphm = 1; + p->pRightmost->selFlags |= SF_UsesEphemeral; assert( p->pEList ); } @@ -2002,7 +1549,7 @@ static int multiSelect( */ assert( !pPrior->pOrderBy ); sqlite3SelectDestInit(&uniondest, priorOp, unionTab); - rc = sqlite3Select(pParse, pPrior, &uniondest, 0, 0, 0); + rc = sqlite3Select(pParse, pPrior, &uniondest); if( rc ){ goto multi_select_end; } @@ -2016,13 +1563,13 @@ static int multiSelect( op = SRT_Union; } p->pPrior = 0; - p->disallowOrderBy = 0; pLimit = p->pLimit; p->pLimit = 0; pOffset = p->pOffset; p->pOffset = 0; uniondest.eDest = op; - rc = sqlite3Select(pParse, p, &uniondest, 0, 0, 0); + rc = sqlite3Select(pParse, p, &uniondest); + testcase( rc!=SQLITE_OK ); /* Query flattening in sqlite3Select() might refill p->pOrderBy. ** Be sure to delete p->pOrderBy, therefore, to avoid a memory leak. */ sqlite3ExprListDelete(db, p->pOrderBy); @@ -2034,18 +1581,15 @@ static int multiSelect( p->pOffset = pOffset; p->iLimit = 0; p->iOffset = 0; - if( rc ){ - goto multi_select_end; - } - /* Convert the data in the temporary table into whatever form ** it is that we currently need. - */ - if( dest.eDest!=priorOp || unionTab!=dest.iParm ){ + */ + assert( unionTab==dest.iParm || dest.eDest!=priorOp ); + if( dest.eDest!=priorOp ){ int iCont, iBreak, iStart; assert( p->pEList ); - if( dest.eDest==SRT_Callback ){ + if( dest.eDest==SRT_Output ){ Select *pFirst = p; while( pFirst->pPrior ) pFirst = pFirst->pPrior; generateColumnNames(pParse, 0, pFirst->pEList); @@ -2064,7 +1608,7 @@ static int multiSelect( } break; } - case TK_INTERSECT: { + default: assert( p->op==TK_INTERSECT ); { int tab1, tab2; int iCont, iBreak, iStart; Expr *pLimit, *pOffset; @@ -2083,13 +1627,13 @@ static int multiSelect( addr = sqlite3VdbeAddOp2(v, OP_OpenEphemeral, tab1, 0); assert( p->addrOpenEphm[0] == -1 ); p->addrOpenEphm[0] = addr; - p->pRightmost->usesEphm = 1; + p->pRightmost->selFlags |= SF_UsesEphemeral; assert( p->pEList ); /* Code the SELECTs to our left into temporary table "tab1". */ sqlite3SelectDestInit(&intersectdest, SRT_Union, tab1); - rc = sqlite3Select(pParse, pPrior, &intersectdest, 0, 0, 0); + rc = sqlite3Select(pParse, pPrior, &intersectdest); if( rc ){ goto multi_select_end; } @@ -2105,21 +1649,19 @@ static int multiSelect( pOffset = p->pOffset; p->pOffset = 0; intersectdest.iParm = tab2; - rc = sqlite3Select(pParse, p, &intersectdest, 0, 0, 0); + rc = sqlite3Select(pParse, p, &intersectdest); + testcase( rc!=SQLITE_OK ); pDelete = p->pPrior; p->pPrior = pPrior; sqlite3ExprDelete(db, p->pLimit); p->pLimit = pLimit; p->pOffset = pOffset; - if( rc ){ - goto multi_select_end; - } /* Generate code to take the intersection of the two temporary ** tables. */ assert( p->pEList ); - if( dest.eDest==SRT_Callback ){ + if( dest.eDest==SRT_Output ){ Select *pFirst = p; while( pFirst->pPrior ) pFirst = pFirst->pPrior; generateColumnNames(pParse, 0, pFirst->pEList); @@ -2152,7 +1694,7 @@ static int multiSelect( ** SELECT might also skip this part if it has no ORDER BY clause and ** no temp tables are required. */ - if( p->usesEphm ){ + if( p->selFlags & SF_UsesEphemeral ){ int i; /* Loop counter */ KeyInfo *pKeyInfo; /* Collating sequence for the result set */ Select *pLoop; /* For looping through SELECT statements */ @@ -2169,7 +1711,7 @@ static int multiSelect( } pKeyInfo->enc = ENC(db); - pKeyInfo->nField = nCol; + pKeyInfo->nField = (u16)nCol; for(i=0, apColl=pKeyInfo->aColl; i<nCol; i++, apColl++){ *apColl = multiSelectCollSeq(pParse, p, i); @@ -2266,6 +1808,8 @@ static int generateOutputSubroutine( case SRT_EphemTab: { int r1 = sqlite3GetTempReg(pParse); int r2 = sqlite3GetTempReg(pParse); + testcase( pDest->eDest==SRT_Table ); + testcase( pDest->eDest==SRT_EphemTab ); sqlite3VdbeAddOp3(v, OP_MakeRecord, pIn->iMem, pIn->nMem, r1); sqlite3VdbeAddOp2(v, OP_NewRowid, pDest->iParm, r2); sqlite3VdbeAddOp3(v, OP_Insert, pDest->iParm, r1, r2); @@ -2315,9 +1859,8 @@ static int generateOutputSubroutine( } #endif /* #ifndef SQLITE_OMIT_SUBQUERY */ - /* Send the data to the callback function or to a subroutine. In the - ** case of a subroutine, the subroutine itself is responsible for - ** popping the data from the stack. + /* The results are stored in a sequence of registers + ** starting at pDest->iMem. Then the co-routine yields. */ case SRT_Coroutine: { if( pDest->iMem==0 ){ @@ -2329,22 +1872,20 @@ static int generateOutputSubroutine( break; } - case SRT_Callback: { - sqlite3VdbeAddOp2(v, OP_ResultRow, pIn->iMem, pIn->nMem); - sqlite3ExprCacheAffinityChange(pParse, pIn->iMem, pIn->nMem); - break; - } - -#if !defined(SQLITE_OMIT_TRIGGER) - /* Discard the results. This is used for SELECT statements inside - ** the body of a TRIGGER. The purpose of such selects is to call - ** user-defined functions that have side effects. We do not care - ** about the actual results of the select. + /* If none of the above, then the result destination must be + ** SRT_Output. This routine is never called with any other + ** destination other than the ones handled above or SRT_Output. + ** + ** For SRT_Output, results are stored in a sequence of registers. + ** Then the OP_ResultRow opcode is used to cause sqlite3_step() to + ** return the next row of result. */ default: { + assert( pDest->eDest==SRT_Output ); + sqlite3VdbeAddOp2(v, OP_ResultRow, pIn->iMem, pIn->nMem); + sqlite3ExprCacheAffinityChange(pParse, pIn->iMem, pIn->nMem); break; } -#endif } /* Jump to the end of the loop if the LIMIT is reached. @@ -2467,7 +2008,7 @@ static int multiSelectOrderBy( int regOutA; /* Address register for the output-A subroutine */ int regOutB; /* Address register for the output-B subroutine */ int addrOutA; /* Address of the output-A subroutine */ - int addrOutB; /* Address of the output-B subroutine */ + int addrOutB = 0; /* Address of the output-B subroutine */ int addrEofA; /* Address of the select-A-exhausted subroutine */ int addrEofB; /* Address of the select-B-exhausted subroutine */ int addrAltB; /* Address of the A<B subroutine */ @@ -2482,18 +2023,18 @@ static int multiSelectOrderBy( int labelEnd; /* Label for the end of the overall SELECT stmt */ int j1; /* Jump instructions that get retargetted */ int op; /* One of TK_ALL, TK_UNION, TK_EXCEPT, TK_INTERSECT */ - KeyInfo *pKeyDup; /* Comparison information for duplicate removal */ + KeyInfo *pKeyDup = 0; /* Comparison information for duplicate removal */ KeyInfo *pKeyMerge; /* Comparison information for merging rows */ sqlite3 *db; /* Database connection */ ExprList *pOrderBy; /* The ORDER BY clause */ int nOrderBy; /* Number of terms in the ORDER BY clause */ int *aPermute; /* Mapping from ORDER BY terms to result set columns */ - u8 NotUsed; /* Dummy variables */ assert( p->pOrderBy!=0 ); + assert( pKeyDup==0 ); /* "Managed" code needs this. Ticket #3382. */ db = pParse->db; v = pParse->pVdbe; - if( v==0 ) return SQLITE_NOMEM; + assert( v!=0 ); /* Already thrown the error if VDBE alloc failed */ labelEnd = sqlite3VdbeMakeLabel(v); labelCmpr = sqlite3VdbeMakeLabel(v); @@ -2505,9 +2046,6 @@ static int multiSelectOrderBy( assert( pPrior->pOrderBy==0 ); pOrderBy = p->pOrderBy; assert( pOrderBy ); - if( processCompoundOrderBy(pParse, p) ){ - return SQLITE_ERROR; - } nOrderBy = pOrderBy->nExpr; /* For operators other than UNION ALL we have to make sure that @@ -2516,25 +2054,24 @@ static int multiSelectOrderBy( */ if( op!=TK_ALL ){ for(i=1; db->mallocFailed==0 && i<=p->pEList->nExpr; i++){ - for(j=0; j<nOrderBy; j++){ - Expr *pTerm = pOrderBy->a[j].pExpr; - assert( pTerm->op==TK_INTEGER ); - assert( (pTerm->flags & EP_IntValue)!=0 ); - if( pTerm->iTable==i ) break; + struct ExprList_item *pItem; + for(j=0, pItem=pOrderBy->a; j<nOrderBy; j++, pItem++){ + assert( pItem->iCol>0 ); + if( pItem->iCol==i ) break; } if( j==nOrderBy ){ - Expr *pNew = sqlite3PExpr(pParse, TK_INTEGER, 0, 0, 0); + Expr *pNew = sqlite3Expr(db, TK_INTEGER, 0); if( pNew==0 ) return SQLITE_NOMEM; pNew->flags |= EP_IntValue; - pNew->iTable = i; - pOrderBy = sqlite3ExprListAppend(pParse, pOrderBy, pNew, 0); - nOrderBy++; + pNew->u.iValue = i; + pOrderBy = sqlite3ExprListAppend(pParse, pOrderBy, pNew); + pOrderBy->a[nOrderBy++].iCol = (u16)i; } } } /* Compute the comparison permutation and keyinfo that is used with - ** the permutation in order to comparisons to determine if the next + ** the permutation used to determine if the next ** row of results comes from selectA or selectB. Also add explicit ** collations to the ORDER BY clause terms so that when the subqueries ** to the right and the left are evaluated, they use the correct @@ -2542,18 +2079,16 @@ static int multiSelectOrderBy( */ aPermute = sqlite3DbMallocRaw(db, sizeof(int)*nOrderBy); if( aPermute ){ - for(i=0; i<nOrderBy; i++){ - Expr *pTerm = pOrderBy->a[i].pExpr; - assert( pTerm->op==TK_INTEGER ); - assert( (pTerm->flags & EP_IntValue)!=0 ); - aPermute[i] = pTerm->iTable-1; - assert( aPermute[i]>=0 && aPermute[i]<p->pEList->nExpr ); + struct ExprList_item *pItem; + for(i=0, pItem=pOrderBy->a; i<nOrderBy; i++, pItem++){ + assert( pItem->iCol>0 && pItem->iCol<=p->pEList->nExpr ); + aPermute[i] = pItem->iCol - 1; } pKeyMerge = sqlite3DbMallocRaw(db, sizeof(*pKeyMerge)+nOrderBy*(sizeof(CollSeq*)+1)); if( pKeyMerge ){ pKeyMerge->aSortOrder = (u8*)&pKeyMerge->aColl[nOrderBy]; - pKeyMerge->nField = nOrderBy; + pKeyMerge->nField = (u16)nOrderBy; pKeyMerge->enc = ENC(db); for(i=0; i<nOrderBy; i++){ CollSeq *pColl; @@ -2576,7 +2111,7 @@ static int multiSelectOrderBy( /* Reattach the ORDER BY clause to the query. */ p->pOrderBy = pOrderBy; - pPrior->pOrderBy = sqlite3ExprListDup(pParse->db, pOrderBy); + pPrior->pOrderBy = sqlite3ExprListDup(pParse->db, pOrderBy, 0); /* Allocate a range of temporary registers and the KeyInfo needed ** for the logic that removes duplicate result rows when the @@ -2586,14 +2121,14 @@ static int multiSelectOrderBy( regPrev = 0; }else{ int nExpr = p->pEList->nExpr; - assert( nOrderBy>=nExpr ); + assert( nOrderBy>=nExpr || db->mallocFailed ); regPrev = sqlite3GetTempRange(pParse, nExpr+1); sqlite3VdbeAddOp2(v, OP_Integer, 0, regPrev); pKeyDup = sqlite3DbMallocZero(db, sizeof(*pKeyDup) + nExpr*(sizeof(CollSeq*)+1) ); if( pKeyDup ){ pKeyDup->aSortOrder = (u8*)&pKeyDup->aColl[nExpr]; - pKeyDup->nField = nExpr; + pKeyDup->nField = (u16)nExpr; pKeyDup->enc = ENC(db); for(i=0; i<nExpr; i++){ pKeyDup->aColl[i] = multiSelectCollSeq(pParse, p, i); @@ -2606,9 +2141,9 @@ static int multiSelectOrderBy( */ p->pPrior = 0; pPrior->pRightmost = 0; - processOrderGroupBy(pParse, p, p->pOrderBy, 1, &NotUsed); + sqlite3ResolveOrderGroupBy(pParse, p, p->pOrderBy, "ORDER"); if( pPrior->pPrior==0 ){ - processOrderGroupBy(pParse, pPrior, pPrior->pOrderBy, 1, &NotUsed); + sqlite3ResolveOrderGroupBy(pParse, pPrior, pPrior->pOrderBy, "ORDER"); } /* Compute the limit registers */ @@ -2648,7 +2183,7 @@ static int multiSelectOrderBy( */ VdbeNoopComment((v, "Begin coroutine for left SELECT")); pPrior->iLimit = regLimitA; - sqlite3Select(pParse, pPrior, &destA, 0, 0, 0); + sqlite3Select(pParse, pPrior, &destA); sqlite3VdbeAddOp2(v, OP_Integer, 1, regEofA); sqlite3VdbeAddOp1(v, OP_Yield, regAddrA); VdbeNoopComment((v, "End coroutine for left SELECT")); @@ -2662,7 +2197,7 @@ static int multiSelectOrderBy( savedOffset = p->iOffset; p->iLimit = regLimitB; p->iOffset = 0; - sqlite3Select(pParse, p, &destB, 0, 0, 0); + sqlite3Select(pParse, p, &destB); p->iLimit = savedLimit; p->iOffset = savedOffset; sqlite3VdbeAddOp2(v, OP_Integer, 1, regEofB); @@ -2777,7 +2312,7 @@ static int multiSelectOrderBy( /* Set the number of output columns */ - if( pDest->eDest==SRT_Callback ){ + if( pDest->eDest==SRT_Output ){ Select *pFirst = pPrior; while( pFirst->pPrior ) pFirst = pFirst->pPrior; generateColumnNames(pParse, 0, pFirst->pEList); @@ -2814,44 +2349,37 @@ static void substSelect(sqlite3*, Select *, int, ExprList *); ** changes to pExpr so that it refers directly to the source table ** of the subquery rather the result set of the subquery. */ -static void substExpr( +static Expr *substExpr( sqlite3 *db, /* Report malloc errors to this connection */ Expr *pExpr, /* Expr in which substitution occurs */ int iTable, /* Table to be substituted */ ExprList *pEList /* Substitute expressions */ ){ - if( pExpr==0 ) return; + if( pExpr==0 ) return 0; if( pExpr->op==TK_COLUMN && pExpr->iTable==iTable ){ if( pExpr->iColumn<0 ){ pExpr->op = TK_NULL; }else{ Expr *pNew; assert( pEList!=0 && pExpr->iColumn<pEList->nExpr ); - assert( pExpr->pLeft==0 && pExpr->pRight==0 && pExpr->pList==0 ); - pNew = pEList->a[pExpr->iColumn].pExpr; - assert( pNew!=0 ); - pExpr->op = pNew->op; - assert( pExpr->pLeft==0 ); - pExpr->pLeft = sqlite3ExprDup(db, pNew->pLeft); - assert( pExpr->pRight==0 ); - pExpr->pRight = sqlite3ExprDup(db, pNew->pRight); - assert( pExpr->pList==0 ); - pExpr->pList = sqlite3ExprListDup(db, pNew->pList); - pExpr->iTable = pNew->iTable; - pExpr->pTab = pNew->pTab; - pExpr->iColumn = pNew->iColumn; - pExpr->iAgg = pNew->iAgg; - sqlite3TokenCopy(db, &pExpr->token, &pNew->token); - sqlite3TokenCopy(db, &pExpr->span, &pNew->span); - pExpr->pSelect = sqlite3SelectDup(db, pNew->pSelect); - pExpr->flags = pNew->flags; + assert( pExpr->pLeft==0 && pExpr->pRight==0 ); + pNew = sqlite3ExprDup(db, pEList->a[pExpr->iColumn].pExpr, 0); + if( pNew && pExpr->pColl ){ + pNew->pColl = pExpr->pColl; + } + sqlite3ExprDelete(db, pExpr); + pExpr = pNew; } }else{ - substExpr(db, pExpr->pLeft, iTable, pEList); - substExpr(db, pExpr->pRight, iTable, pEList); - substSelect(db, pExpr->pSelect, iTable, pEList); - substExprList(db, pExpr->pList, iTable, pEList); + pExpr->pLeft = substExpr(db, pExpr->pLeft, iTable, pEList); + pExpr->pRight = substExpr(db, pExpr->pRight, iTable, pEList); + if( ExprHasProperty(pExpr, EP_xIsSelect) ){ + substSelect(db, pExpr->x.pSelect, iTable, pEList); + }else{ + substExprList(db, pExpr->x.pList, iTable, pEList); + } } + return pExpr; } static void substExprList( sqlite3 *db, /* Report malloc errors here */ @@ -2862,7 +2390,7 @@ static void substExprList( int i; if( pList==0 ) return; for(i=0; i<pList->nExpr; i++){ - substExpr(db, pList->a[i].pExpr, iTable, pEList); + pList->a[i].pExpr = substExpr(db, pList->a[i].pExpr, iTable, pEList); } } static void substSelect( @@ -2871,13 +2399,23 @@ static void substSelect( int iTable, /* Table to be replaced */ ExprList *pEList /* Substitute values */ ){ + SrcList *pSrc; + struct SrcList_item *pItem; + int i; if( !p ) return; substExprList(db, p->pEList, iTable, pEList); substExprList(db, p->pGroupBy, iTable, pEList); substExprList(db, p->pOrderBy, iTable, pEList); - substExpr(db, p->pHaving, iTable, pEList); - substExpr(db, p->pWhere, iTable, pEList); + p->pHaving = substExpr(db, p->pHaving, iTable, pEList); + p->pWhere = substExpr(db, p->pWhere, iTable, pEList); substSelect(db, p->pPrior, iTable, pEList); + pSrc = p->pSrc; + assert( pSrc ); /* Even for (SELECT 1) we have: pSrc!=0 but pSrc->nSrc==0 */ + if( ALWAYS(pSrc) ){ + for(i=pSrc->nSrc, pItem=pSrc->a; i>0; i--, pItem++){ + substSelect(db, pItem->pSelect, iTable, pEList); + } + } } #endif /* !defined(SQLITE_OMIT_SUBQUERY) || !defined(SQLITE_OMIT_VIEW) */ @@ -2915,8 +2453,8 @@ static void substSelect( ** ** (2) The subquery is not an aggregate or the outer query is not a join. ** -** (3) The subquery is not the right operand of a left outer join, or -** the subquery is not itself a join. (Ticket #306) +** (3) The subquery is not the right operand of a left outer join +** (Originally ticket #306. Strenghtened by ticket #3300) ** ** (4) The subquery is not DISTINCT or the outer query is not a join. ** @@ -2938,8 +2476,8 @@ static void substSelect( ** ** (11) The subquery and the outer query do not both have ORDER BY clauses. ** -** (12) The subquery is not the right term of a LEFT OUTER JOIN or the -** subquery has no WHERE clause. (added by ticket #350) +** (12) Not implemented. Subsumed into restriction (3). Was previously +** a separate restriction deriving from ticket #350. ** ** (13) The subquery and outer query do not both use LIMIT ** @@ -2969,6 +2507,15 @@ static void substSelect( ** ORDER by clause of the parent must be simple references to ** columns of the sub-query. ** +** (19) The subquery does not use LIMIT or the outer query does not +** have a WHERE clause. +** +** (20) If the sub-query is a compound select, then it must not use +** an ORDER BY clause. Ticket #3773. We could relax this constraint +** somewhat by saying that the terms of the ORDER BY clause must +** appear as unmodified result columns in the outer query. But +** have other optimizations in mind to deal with that case. +** ** In this routine, the "p" parameter is a pointer to the outer query. ** The subquery is p->pSrc->a[iFrom]. isAgg is true if the outer query ** uses aggregates and subqueryIsAgg is true if the subquery uses aggregates. @@ -3001,7 +2548,8 @@ static int flattenSubquery( /* Check to see if flattening is permitted. Return 0 if not. */ - if( p==0 ) return 0; + assert( p!=0 ); + assert( p->pPrior==0 ); /* Unable to flatten compound queries */ pSrc = p->pSrc; assert( pSrc && iFrom>=0 && iFrom<pSrc->nSrc ); pSubitem = &pSrc->a[iFrom]; @@ -3023,17 +2571,21 @@ static int flattenSubquery( return 0; /* Restriction (15) */ } if( pSubSrc->nSrc==0 ) return 0; /* Restriction (7) */ - if( (pSub->isDistinct || pSub->pLimit) + if( ((pSub->selFlags & SF_Distinct)!=0 || pSub->pLimit) && (pSrc->nSrc>1 || isAgg) ){ /* Restrictions (4)(5)(8)(9) */ return 0; } - if( p->isDistinct && subqueryIsAgg ) return 0; /* Restriction (6) */ - if( (p->disallowOrderBy || p->pOrderBy) && pSub->pOrderBy ){ + if( (p->selFlags & SF_Distinct)!=0 && subqueryIsAgg ){ + return 0; /* Restriction (6) */ + } + if( p->pOrderBy && pSub->pOrderBy ){ return 0; /* Restriction (11) */ } if( isAgg && pSub->pOrderBy ) return 0; /* Restriction (16) */ + if( pSub->pLimit && p->pWhere ) return 0; /* Restriction (19) */ - /* Restriction 3: If the subquery is a join, make sure the subquery is + /* OBSOLETE COMMENT 1: + ** Restriction 3: If the subquery is a join, make sure the subquery is ** not used as the right operand of an outer join. Examples of why this ** is not allowed: ** @@ -3044,12 +2596,9 @@ static int flattenSubquery( ** (t1 LEFT OUTER JOIN t2) JOIN t3 ** ** which is not at all the same thing. - */ - if( pSubSrc->nSrc>1 && (pSubitem->jointype & JT_OUTER)!=0 ){ - return 0; - } - - /* Restriction 12: If the subquery is the right operand of a left outer + ** + ** OBSOLETE COMMENT 2: + ** Restriction 12: If the subquery is the right operand of a left outer ** join, make sure the subquery has no WHERE clause. ** An examples of why this is not allowed: ** @@ -3061,8 +2610,13 @@ static int flattenSubquery( ** ** But the t2.x>0 test will always fail on a NULL row of t2, which ** effectively converts the OUTER JOIN into an INNER JOIN. + ** + ** THIS OVERRIDES OBSOLETE COMMENTS 1 AND 2 ABOVE: + ** Ticket #3300 shows that flattening the right term of a LEFT JOIN + ** is fraught with danger. Best to avoid the whole thing. If the + ** subquery is the right term of a LEFT JOIN, then do not flatten. */ - if( (pSubitem->jointype & JT_OUTER)!=0 && pSub->pWhere!=0 ){ + if( (pSubitem->jointype & JT_OUTER)!=0 ){ return 0; } @@ -3072,13 +2626,18 @@ static int flattenSubquery( ** queries. */ if( pSub->pPrior ){ - if( p->pPrior || isAgg || p->isDistinct || pSrc->nSrc!=1 ){ + if( pSub->pOrderBy ){ + return 0; /* Restriction 20 */ + } + if( isAgg || (p->selFlags & SF_Distinct)!=0 || pSrc->nSrc!=1 ){ return 0; } for(pSub1=pSub; pSub1; pSub1=pSub1->pPrior){ - if( pSub1->isAgg || pSub1->isDistinct + testcase( (pSub1->selFlags & (SF_Distinct|SF_Aggregate))==SF_Distinct ); + testcase( (pSub1->selFlags & (SF_Distinct|SF_Aggregate))==SF_Aggregate ); + if( (pSub1->selFlags & (SF_Distinct|SF_Aggregate))!=0 || (pSub1->pPrior && pSub1->op!=TK_ALL) - || !pSub1->pSrc || pSub1->pSrc->nSrc!=1 + || NEVER(pSub1->pSrc==0) || pSub1->pSrc->nSrc!=1 ){ return 0; } @@ -3088,97 +2647,170 @@ static int flattenSubquery( if( p->pOrderBy ){ int ii; for(ii=0; ii<p->pOrderBy->nExpr; ii++){ - Expr *pExpr = p->pOrderBy->a[ii].pExpr; - if( pExpr->op!=TK_COLUMN || pExpr->iTable!=iParent ){ - return 0; - } + if( p->pOrderBy->a[ii].iCol==0 ) return 0; } } } + /***** If we reach this point, flattening is permitted. *****/ + + /* Authorize the subquery */ pParse->zAuthContext = pSubitem->zName; sqlite3AuthCheck(pParse, SQLITE_SELECT, 0, 0, 0); pParse->zAuthContext = zSavedAuthContext; - /* If the sub-query is a compound SELECT statement, then it must be - ** a UNION ALL and the parent query must be of the form: + /* If the sub-query is a compound SELECT statement, then (by restrictions + ** 17 and 18 above) it must be a UNION ALL and the parent query must + ** be of the form: ** ** SELECT <expr-list> FROM (<sub-query>) <where-clause> ** ** followed by any ORDER BY, LIMIT and/or OFFSET clauses. This block - ** creates N copies of the parent query without any ORDER BY, LIMIT or + ** creates N-1 copies of the parent query without any ORDER BY, LIMIT or ** OFFSET clauses and joins them to the left-hand-side of the original ** using UNION ALL operators. In this case N is the number of simple ** select statements in the compound sub-query. + ** + ** Example: + ** + ** SELECT a+1 FROM ( + ** SELECT x FROM tab + ** UNION ALL + ** SELECT y FROM tab + ** UNION ALL + ** SELECT abs(z*2) FROM tab2 + ** ) WHERE a!=5 ORDER BY 1 + ** + ** Transformed into: + ** + ** SELECT x+1 FROM tab WHERE x+1!=5 + ** UNION ALL + ** SELECT y+1 FROM tab WHERE y+1!=5 + ** UNION ALL + ** SELECT abs(z*2)+1 FROM tab2 WHERE abs(z*2)+1!=5 + ** ORDER BY 1 + ** + ** We call this the "compound-subquery flattening". */ for(pSub=pSub->pPrior; pSub; pSub=pSub->pPrior){ Select *pNew; ExprList *pOrderBy = p->pOrderBy; Expr *pLimit = p->pLimit; - Expr *pOffset = p->pOffset; Select *pPrior = p->pPrior; p->pOrderBy = 0; p->pSrc = 0; p->pPrior = 0; p->pLimit = 0; - pNew = sqlite3SelectDup(db, p); - pNew->pPrior = pPrior; - p->pPrior = pNew; + pNew = sqlite3SelectDup(db, p, 0); + p->pLimit = pLimit; p->pOrderBy = pOrderBy; - p->op = TK_ALL; p->pSrc = pSrc; - p->pLimit = pLimit; - p->pOffset = pOffset; + p->op = TK_ALL; p->pRightmost = 0; - pNew->pRightmost = 0; + if( pNew==0 ){ + pNew = pPrior; + }else{ + pNew->pPrior = pPrior; + pNew->pRightmost = 0; + } + p->pPrior = pNew; + if( db->mallocFailed ) return 1; } - /* If we reach this point, it means flattening is permitted for the - ** iFrom-th entry of the FROM clause in the outer query. + /* Begin flattening the iFrom-th entry of the FROM clause + ** in the outer query. */ pSub = pSub1 = pSubitem->pSelect; + + /* Delete the transient table structure associated with the + ** subquery + */ + sqlite3DbFree(db, pSubitem->zDatabase); + sqlite3DbFree(db, pSubitem->zName); + sqlite3DbFree(db, pSubitem->zAlias); + pSubitem->zDatabase = 0; + pSubitem->zName = 0; + pSubitem->zAlias = 0; + pSubitem->pSelect = 0; + + /* Defer deleting the Table object associated with the + ** subquery until code generation is + ** complete, since there may still exist Expr.pTab entries that + ** refer to the subquery even after flattening. Ticket #3346. + ** + ** pSubitem->pTab is always non-NULL by test restrictions and tests above. + */ + if( ALWAYS(pSubitem->pTab!=0) ){ + Table *pTabToDel = pSubitem->pTab; + if( pTabToDel->nRef==1 ){ + Parse *pToplevel = sqlite3ParseToplevel(pParse); + pTabToDel->pNextZombie = pToplevel->pZombieTab; + pToplevel->pZombieTab = pTabToDel; + }else{ + pTabToDel->nRef--; + } + pSubitem->pTab = 0; + } + + /* The following loop runs once for each term in a compound-subquery + ** flattening (as described above). If we are doing a different kind + ** of flattening - a flattening other than a compound-subquery flattening - + ** then this loop only runs once. + ** + ** This loop moves all of the FROM elements of the subquery into the + ** the FROM clause of the outer query. Before doing this, remember + ** the cursor number for the original outer query FROM element in + ** iParent. The iParent cursor will never be used. Subsequent code + ** will scan expressions looking for iParent references and replace + ** those references with expressions that resolve to the subquery FROM + ** elements we are now copying in. + */ for(pParent=p; pParent; pParent=pParent->pPrior, pSub=pSub->pPrior){ - int nSubSrc = pSubSrc->nSrc; - int jointype = 0; - pSubSrc = pSub->pSrc; - pSrc = pParent->pSrc; - - /* Move all of the FROM elements of the subquery into the - ** the FROM clause of the outer query. Before doing this, remember - ** the cursor number for the original outer query FROM element in - ** iParent. The iParent cursor will never be used. Subsequent code - ** will scan expressions looking for iParent references and replace - ** those references with expressions that resolve to the subquery FROM - ** elements we are now copying in. - */ + int nSubSrc; + u8 jointype = 0; + pSubSrc = pSub->pSrc; /* FROM clause of subquery */ + nSubSrc = pSubSrc->nSrc; /* Number of terms in subquery FROM clause */ + pSrc = pParent->pSrc; /* FROM clause of the outer query */ + if( pSrc ){ - pSubitem = &pSrc->a[iFrom]; - nSubSrc = pSubSrc->nSrc; + assert( pParent==p ); /* First time through the loop */ jointype = pSubitem->jointype; - sqlite3DeleteTable(pSubitem->pTab); - sqlite3DbFree(db, pSubitem->zDatabase); - sqlite3DbFree(db, pSubitem->zName); - sqlite3DbFree(db, pSubitem->zAlias); - pSubitem->pTab = 0; - pSubitem->zDatabase = 0; - pSubitem->zName = 0; - pSubitem->zAlias = 0; - } - if( nSubSrc!=1 || !pSrc ){ - int extra = nSubSrc - 1; - for(i=(pSrc?1:0); i<nSubSrc; i++){ - pSrc = sqlite3SrcListAppend(db, pSrc, 0, 0); - if( pSrc==0 ){ - pParent->pSrc = 0; - return 1; - } + }else{ + assert( pParent!=p ); /* 2nd and subsequent times through the loop */ + pSrc = pParent->pSrc = sqlite3SrcListAppend(db, 0, 0, 0); + if( pSrc==0 ){ + assert( db->mallocFailed ); + break; } - pParent->pSrc = pSrc; - for(i=pSrc->nSrc-1; i-extra>=iFrom; i--){ - pSrc->a[i] = pSrc->a[i-extra]; + } + + /* The subquery uses a single slot of the FROM clause of the outer + ** query. If the subquery has more than one element in its FROM clause, + ** then expand the outer query to make space for it to hold all elements + ** of the subquery. + ** + ** Example: + ** + ** SELECT * FROM tabA, (SELECT * FROM sub1, sub2), tabB; + ** + ** The outer query has 3 slots in its FROM clause. One slot of the + ** outer query (the middle slot) is used by the subquery. The next + ** block of code will expand the out query to 4 slots. The middle + ** slot is expanded to two slots in order to make space for the + ** two elements in the FROM clause of the subquery. + */ + if( nSubSrc>1 ){ + pParent->pSrc = pSrc = sqlite3SrcListEnlarge(db, pSrc, nSubSrc-1,iFrom+1); + if( db->mallocFailed ){ + break; } } + + /* Transfer the FROM clause terms from the subquery into the + ** outer query. + */ for(i=0; i<nSubSrc; i++){ + sqlite3IdListDelete(db, pSrc->a[i+iFrom].pUsing); pSrc->a[i+iFrom] = pSubSrc->a[i]; memset(&pSubSrc->a[i], 0, sizeof(pSubSrc->a[i])); } @@ -3198,16 +2830,17 @@ static int flattenSubquery( */ pList = pParent->pEList; for(i=0; i<pList->nExpr; i++){ - Expr *pExpr; - if( pList->a[i].zName==0 && (pExpr = pList->a[i].pExpr)->span.z!=0 ){ - pList->a[i].zName = - sqlite3DbStrNDup(db, (char*)pExpr->span.z, pExpr->span.n); + if( pList->a[i].zName==0 ){ + const char *zSpan = pList->a[i].zSpan; + if( ALWAYS(zSpan) ){ + pList->a[i].zName = sqlite3DbStrDup(db, zSpan); + } } } substExprList(db, pParent->pEList, iParent, pSub->pEList); if( isAgg ){ substExprList(db, pParent->pGroupBy, iParent, pSub->pEList); - substExpr(db, pParent->pHaving, iParent, pSub->pEList); + pParent->pHaving = substExpr(db, pParent->pHaving, iParent, pSub->pEList); } if( pSub->pOrderBy ){ assert( pParent->pOrderBy==0 ); @@ -3217,7 +2850,7 @@ static int flattenSubquery( substExprList(db, pParent->pOrderBy, iParent, pSub->pEList); } if( pSub->pWhere ){ - pWhere = sqlite3ExprDup(db, pSub->pWhere); + pWhere = sqlite3ExprDup(db, pSub->pWhere, 0); }else{ pWhere = 0; } @@ -3225,20 +2858,20 @@ static int flattenSubquery( assert( pParent->pHaving==0 ); pParent->pHaving = pParent->pWhere; pParent->pWhere = pWhere; - substExpr(db, pParent->pHaving, iParent, pSub->pEList); + pParent->pHaving = substExpr(db, pParent->pHaving, iParent, pSub->pEList); pParent->pHaving = sqlite3ExprAnd(db, pParent->pHaving, - sqlite3ExprDup(db, pSub->pHaving)); + sqlite3ExprDup(db, pSub->pHaving, 0)); assert( pParent->pGroupBy==0 ); - pParent->pGroupBy = sqlite3ExprListDup(db, pSub->pGroupBy); + pParent->pGroupBy = sqlite3ExprListDup(db, pSub->pGroupBy, 0); }else{ - substExpr(db, pParent->pWhere, iParent, pSub->pEList); + pParent->pWhere = substExpr(db, pParent->pWhere, iParent, pSub->pEList); pParent->pWhere = sqlite3ExprAnd(db, pParent->pWhere, pWhere); } /* The flattened query is distinct if either the inner or the ** outer query is distinct. */ - pParent->isDistinct = pParent->isDistinct || pSub->isDistinct; + pParent->selFlags |= pSub->selFlags & SF_Distinct; /* ** SELECT ... FROM (SELECT ... LIMIT a OFFSET b) LIMIT x OFFSET y; @@ -3272,152 +2905,448 @@ static int flattenSubquery( ** 2. There is a single expression in the result set, and it is ** either min(x) or max(x), where x is a column reference. */ -static int minMaxQuery(Parse *pParse, Select *p){ +static u8 minMaxQuery(Select *p){ Expr *pExpr; ExprList *pEList = p->pEList; if( pEList->nExpr!=1 ) return WHERE_ORDERBY_NORMAL; pExpr = pEList->a[0].pExpr; - pEList = pExpr->pList; - if( pExpr->op!=TK_AGG_FUNCTION || pEList==0 || pEList->nExpr!=1 ) return 0; + if( pExpr->op!=TK_AGG_FUNCTION ) return 0; + if( NEVER(ExprHasProperty(pExpr, EP_xIsSelect)) ) return 0; + pEList = pExpr->x.pList; + if( pEList==0 || pEList->nExpr!=1 ) return 0; if( pEList->a[0].pExpr->op!=TK_AGG_COLUMN ) return WHERE_ORDERBY_NORMAL; - if( pExpr->token.n!=3 ) return WHERE_ORDERBY_NORMAL; - if( sqlite3StrNICmp((char*)pExpr->token.z,"min",3)==0 ){ + assert( !ExprHasProperty(pExpr, EP_IntValue) ); + if( sqlite3StrICmp(pExpr->u.zToken,"min")==0 ){ return WHERE_ORDERBY_MIN; - }else if( sqlite3StrNICmp((char*)pExpr->token.z,"max",3)==0 ){ + }else if( sqlite3StrICmp(pExpr->u.zToken,"max")==0 ){ return WHERE_ORDERBY_MAX; } return WHERE_ORDERBY_NORMAL; } /* -** This routine resolves any names used in the result set of the -** supplied SELECT statement. If the SELECT statement being resolved -** is a sub-select, then pOuterNC is a pointer to the NameContext -** of the parent SELECT. +** The select statement passed as the first argument is an aggregate query. +** The second argment is the associated aggregate-info object. This +** function tests if the SELECT is of the form: +** +** SELECT count(*) FROM <tbl> +** +** where table is a database table, not a sub-select or view. If the query +** does match this pattern, then a pointer to the Table object representing +** <tbl> is returned. Otherwise, 0 is returned. */ -int sqlite3SelectResolve( - Parse *pParse, /* The parser context */ - Select *p, /* The SELECT statement being coded. */ - NameContext *pOuterNC /* The outer name context. May be NULL. */ -){ - ExprList *pEList; /* Result set. */ - int i; /* For-loop variable used in multiple places */ - NameContext sNC; /* Local name-context */ - ExprList *pGroupBy; /* The group by clause */ - - /* If this routine has run before, return immediately. */ - if( p->isResolved ){ - assert( !pOuterNC ); - return SQLITE_OK; - } - p->isResolved = 1; +static Table *isSimpleCount(Select *p, AggInfo *pAggInfo){ + Table *pTab; + Expr *pExpr; - /* If there have already been errors, do nothing. */ - if( pParse->nErr>0 ){ - return SQLITE_ERROR; - } + assert( !p->pGroupBy ); - /* Prepare the select statement. This call will allocate all cursors - ** required to handle the tables and subqueries in the FROM clause. - */ - if( prepSelectStmt(pParse, p) ){ - return SQLITE_ERROR; + if( p->pWhere || p->pEList->nExpr!=1 + || p->pSrc->nSrc!=1 || p->pSrc->a[0].pSelect + ){ + return 0; } + pTab = p->pSrc->a[0].pTab; + pExpr = p->pEList->a[0].pExpr; + assert( pTab && !pTab->pSelect && pExpr ); - /* Resolve the expressions in the LIMIT and OFFSET clauses. These - ** are not allowed to refer to any names, so pass an empty NameContext. - */ - memset(&sNC, 0, sizeof(sNC)); - sNC.pParse = pParse; - if( sqlite3ExprResolveNames(&sNC, p->pLimit) || - sqlite3ExprResolveNames(&sNC, p->pOffset) ){ - return SQLITE_ERROR; - } + if( IsVirtual(pTab) ) return 0; + if( pExpr->op!=TK_AGG_FUNCTION ) return 0; + if( (pAggInfo->aFunc[0].pFunc->flags&SQLITE_FUNC_COUNT)==0 ) return 0; + if( pExpr->flags&EP_Distinct ) return 0; - /* Set up the local name-context to pass to ExprResolveNames() to - ** resolve the expression-list. - */ - sNC.allowAgg = 1; - sNC.pSrcList = p->pSrc; - sNC.pNext = pOuterNC; + return pTab; +} - /* Resolve names in the result set. */ - pEList = p->pEList; - if( !pEList ) return SQLITE_ERROR; - for(i=0; i<pEList->nExpr; i++){ - Expr *pX = pEList->a[i].pExpr; - if( sqlite3ExprResolveNames(&sNC, pX) ){ +/* +** If the source-list item passed as an argument was augmented with an +** INDEXED BY clause, then try to locate the specified index. If there +** was such a clause and the named index cannot be found, return +** SQLITE_ERROR and leave an error in pParse. Otherwise, populate +** pFrom->pIndex and return SQLITE_OK. +*/ +int sqlite3IndexedByLookup(Parse *pParse, struct SrcList_item *pFrom){ + if( pFrom->pTab && pFrom->zIndex ){ + Table *pTab = pFrom->pTab; + char *zIndex = pFrom->zIndex; + Index *pIdx; + for(pIdx=pTab->pIndex; + pIdx && sqlite3StrICmp(pIdx->zName, zIndex); + pIdx=pIdx->pNext + ); + if( !pIdx ){ + sqlite3ErrorMsg(pParse, "no such index: %s", zIndex, 0); return SQLITE_ERROR; } + pFrom->pIndex = pIdx; + } + return SQLITE_OK; +} + +/* +** This routine is a Walker callback for "expanding" a SELECT statement. +** "Expanding" means to do the following: +** +** (1) Make sure VDBE cursor numbers have been assigned to every +** element of the FROM clause. +** +** (2) Fill in the pTabList->a[].pTab fields in the SrcList that +** defines FROM clause. When views appear in the FROM clause, +** fill pTabList->a[].pSelect with a copy of the SELECT statement +** that implements the view. A copy is made of the view's SELECT +** statement so that we can freely modify or delete that statement +** without worrying about messing up the presistent representation +** of the view. +** +** (3) Add terms to the WHERE clause to accomodate the NATURAL keyword +** on joins and the ON and USING clause of joins. +** +** (4) Scan the list of columns in the result set (pEList) looking +** for instances of the "*" operator or the TABLE.* operator. +** If found, expand each "*" to be every column in every table +** and TABLE.* to be every column in TABLE. +** +*/ +static int selectExpander(Walker *pWalker, Select *p){ + Parse *pParse = pWalker->pParse; + int i, j, k; + SrcList *pTabList; + ExprList *pEList; + struct SrcList_item *pFrom; + sqlite3 *db = pParse->db; + + if( db->mallocFailed ){ + return WRC_Abort; } + if( NEVER(p->pSrc==0) || (p->selFlags & SF_Expanded)!=0 ){ + return WRC_Prune; + } + p->selFlags |= SF_Expanded; + pTabList = p->pSrc; + pEList = p->pEList; - /* If there are no aggregate functions in the result-set, and no GROUP BY - ** expression, do not allow aggregates in any of the other expressions. + /* Make sure cursor numbers have been assigned to all entries in + ** the FROM clause of the SELECT statement. */ - assert( !p->isAgg ); - pGroupBy = p->pGroupBy; - if( pGroupBy || sNC.hasAgg ){ - p->isAgg = 1; - }else{ - sNC.allowAgg = 0; + sqlite3SrcListAssignCursors(pParse, pTabList); + + /* Look up every table named in the FROM clause of the select. If + ** an entry of the FROM clause is a subquery instead of a table or view, + ** then create a transient table structure to describe the subquery. + */ + for(i=0, pFrom=pTabList->a; i<pTabList->nSrc; i++, pFrom++){ + Table *pTab; + if( pFrom->pTab!=0 ){ + /* This statement has already been prepared. There is no need + ** to go further. */ + assert( i==0 ); + return WRC_Prune; + } + if( pFrom->zName==0 ){ +#ifndef SQLITE_OMIT_SUBQUERY + Select *pSel = pFrom->pSelect; + /* A sub-query in the FROM clause of a SELECT */ + assert( pSel!=0 ); + assert( pFrom->pTab==0 ); + sqlite3WalkSelect(pWalker, pSel); + pFrom->pTab = pTab = sqlite3DbMallocZero(db, sizeof(Table)); + if( pTab==0 ) return WRC_Abort; + pTab->dbMem = db->lookaside.bEnabled ? db : 0; + pTab->nRef = 1; + pTab->zName = sqlite3MPrintf(db, "sqlite_subquery_%p_", (void*)pTab); + while( pSel->pPrior ){ pSel = pSel->pPrior; } + selectColumnsFromExprList(pParse, pSel->pEList, &pTab->nCol, &pTab->aCol); + pTab->iPKey = -1; + pTab->tabFlags |= TF_Ephemeral; +#endif + }else{ + /* An ordinary table or view name in the FROM clause */ + assert( pFrom->pTab==0 ); + pFrom->pTab = pTab = + sqlite3LocateTable(pParse,0,pFrom->zName,pFrom->zDatabase); + if( pTab==0 ) return WRC_Abort; + pTab->nRef++; +#if !defined(SQLITE_OMIT_VIEW) || !defined (SQLITE_OMIT_VIRTUALTABLE) + if( pTab->pSelect || IsVirtual(pTab) ){ + /* We reach here if the named table is a really a view */ + if( sqlite3ViewGetColumnNames(pParse, pTab) ) return WRC_Abort; + assert( pFrom->pSelect==0 ); + pFrom->pSelect = sqlite3SelectDup(db, pTab->pSelect, 0); + sqlite3WalkSelect(pWalker, pFrom->pSelect); + } +#endif + } + + /* Locate the index named by the INDEXED BY clause, if any. */ + if( sqlite3IndexedByLookup(pParse, pFrom) ){ + return WRC_Abort; + } } - /* If a HAVING clause is present, then there must be a GROUP BY clause. + /* Process NATURAL keywords, and ON and USING clauses of joins. */ - if( p->pHaving && !pGroupBy ){ - sqlite3ErrorMsg(pParse, "a GROUP BY clause is required before HAVING"); - return SQLITE_ERROR; + if( db->mallocFailed || sqliteProcessJoin(pParse, p) ){ + return WRC_Abort; } - /* Add the expression list to the name-context before parsing the - ** other expressions in the SELECT statement. This is so that - ** expressions in the WHERE clause (etc.) can refer to expressions by - ** aliases in the result set. + /* For every "*" that occurs in the column list, insert the names of + ** all columns in all tables. And for every TABLE.* insert the names + ** of all columns in TABLE. The parser inserted a special expression + ** with the TK_ALL operator for each "*" that it found in the column list. + ** The following code just has to locate the TK_ALL expressions and expand + ** each one to the list of all columns in all tables. ** - ** Minor point: If this is the case, then the expression will be - ** re-evaluated for each reference to it. + ** The first loop just checks to see if there are any "*" operators + ** that need expanding. */ - sNC.pEList = p->pEList; - if( sqlite3ExprResolveNames(&sNC, p->pWhere) || - sqlite3ExprResolveNames(&sNC, p->pHaving) ){ - return SQLITE_ERROR; + for(k=0; k<pEList->nExpr; k++){ + Expr *pE = pEList->a[k].pExpr; + if( pE->op==TK_ALL ) break; + assert( pE->op!=TK_DOT || pE->pRight!=0 ); + assert( pE->op!=TK_DOT || (pE->pLeft!=0 && pE->pLeft->op==TK_ID) ); + if( pE->op==TK_DOT && pE->pRight->op==TK_ALL ) break; } - if( p->pPrior==0 ){ - if( processOrderGroupBy(pParse, p, p->pOrderBy, 1, &sNC.hasAgg) ){ - return SQLITE_ERROR; + if( k<pEList->nExpr ){ + /* + ** If we get here it means the result set contains one or more "*" + ** operators that need to be expanded. Loop through each expression + ** in the result set and expand them one by one. + */ + struct ExprList_item *a = pEList->a; + ExprList *pNew = 0; + int flags = pParse->db->flags; + int longNames = (flags & SQLITE_FullColNames)!=0 + && (flags & SQLITE_ShortColNames)==0; + + for(k=0; k<pEList->nExpr; k++){ + Expr *pE = a[k].pExpr; + assert( pE->op!=TK_DOT || pE->pRight!=0 ); + if( pE->op!=TK_ALL && (pE->op!=TK_DOT || pE->pRight->op!=TK_ALL) ){ + /* This particular expression does not need to be expanded. + */ + pNew = sqlite3ExprListAppend(pParse, pNew, a[k].pExpr); + if( pNew ){ + pNew->a[pNew->nExpr-1].zName = a[k].zName; + pNew->a[pNew->nExpr-1].zSpan = a[k].zSpan; + a[k].zName = 0; + a[k].zSpan = 0; + } + a[k].pExpr = 0; + }else{ + /* This expression is a "*" or a "TABLE.*" and needs to be + ** expanded. */ + int tableSeen = 0; /* Set to 1 when TABLE matches */ + char *zTName; /* text of name of TABLE */ + if( pE->op==TK_DOT ){ + assert( pE->pLeft!=0 ); + assert( !ExprHasProperty(pE->pLeft, EP_IntValue) ); + zTName = pE->pLeft->u.zToken; + }else{ + zTName = 0; + } + for(i=0, pFrom=pTabList->a; i<pTabList->nSrc; i++, pFrom++){ + Table *pTab = pFrom->pTab; + char *zTabName = pFrom->zAlias; + if( zTabName==0 ){ + zTabName = pTab->zName; + } + if( db->mallocFailed ) break; + if( zTName && sqlite3StrICmp(zTName, zTabName)!=0 ){ + continue; + } + tableSeen = 1; + for(j=0; j<pTab->nCol; j++){ + Expr *pExpr, *pRight; + char *zName = pTab->aCol[j].zName; + char *zColname; /* The computed column name */ + char *zToFree; /* Malloced string that needs to be freed */ + Token sColname; /* Computed column name as a token */ + + /* If a column is marked as 'hidden' (currently only possible + ** for virtual tables), do not include it in the expanded + ** result-set list. + */ + if( IsHiddenColumn(&pTab->aCol[j]) ){ + assert(IsVirtual(pTab)); + continue; + } + + if( i>0 && zTName==0 ){ + struct SrcList_item *pLeft = &pTabList->a[i-1]; + if( (pLeft[1].jointype & JT_NATURAL)!=0 && + columnIndex(pLeft->pTab, zName)>=0 ){ + /* In a NATURAL join, omit the join columns from the + ** table on the right */ + continue; + } + if( sqlite3IdListIndex(pLeft[1].pUsing, zName)>=0 ){ + /* In a join with a USING clause, omit columns in the + ** using clause from the table on the right. */ + continue; + } + } + pRight = sqlite3Expr(db, TK_ID, zName); + zColname = zName; + zToFree = 0; + if( longNames || pTabList->nSrc>1 ){ + Expr *pLeft; + pLeft = sqlite3Expr(db, TK_ID, zTabName); + pExpr = sqlite3PExpr(pParse, TK_DOT, pLeft, pRight, 0); + if( longNames ){ + zColname = sqlite3MPrintf(db, "%s.%s", zTabName, zName); + zToFree = zColname; + } + }else{ + pExpr = pRight; + } + pNew = sqlite3ExprListAppend(pParse, pNew, pExpr); + sColname.z = zColname; + sColname.n = sqlite3Strlen30(zColname); + sqlite3ExprListSetName(pParse, pNew, &sColname, 0); + sqlite3DbFree(db, zToFree); + } + } + if( !tableSeen ){ + if( zTName ){ + sqlite3ErrorMsg(pParse, "no such table: %s", zTName); + }else{ + sqlite3ErrorMsg(pParse, "no tables specified"); + } + } + } } + sqlite3ExprListDelete(db, pEList); + p->pEList = pNew; } - if( processOrderGroupBy(pParse, p, pGroupBy, 0, &sNC.hasAgg) ){ - return SQLITE_ERROR; +#if SQLITE_MAX_COLUMN + if( p->pEList && p->pEList->nExpr>db->aLimit[SQLITE_LIMIT_COLUMN] ){ + sqlite3ErrorMsg(pParse, "too many columns in result set"); } +#endif + return WRC_Continue; +} - if( pParse->db->mallocFailed ){ - return SQLITE_NOMEM; - } +/* +** No-op routine for the parse-tree walker. +** +** When this routine is the Walker.xExprCallback then expression trees +** are walked without any actions being taken at each node. Presumably, +** when this routine is used for Walker.xExprCallback then +** Walker.xSelectCallback is set to do something useful for every +** subquery in the parser tree. +*/ +static int exprWalkNoop(Walker *NotUsed, Expr *NotUsed2){ + UNUSED_PARAMETER2(NotUsed, NotUsed2); + return WRC_Continue; +} - /* Make sure the GROUP BY clause does not contain aggregate functions. - */ - if( pGroupBy ){ - struct ExprList_item *pItem; - - for(i=0, pItem=pGroupBy->a; i<pGroupBy->nExpr; i++, pItem++){ - if( ExprHasProperty(pItem->pExpr, EP_Agg) ){ - sqlite3ErrorMsg(pParse, "aggregate functions are not allowed in " - "the GROUP BY clause"); - return SQLITE_ERROR; - } +/* +** This routine "expands" a SELECT statement and all of its subqueries. +** For additional information on what it means to "expand" a SELECT +** statement, see the comment on the selectExpand worker callback above. +** +** Expanding a SELECT statement is the first step in processing a +** SELECT statement. The SELECT statement must be expanded before +** name resolution is performed. +** +** If anything goes wrong, an error message is written into pParse. +** The calling function can detect the problem by looking at pParse->nErr +** and/or pParse->db->mallocFailed. +*/ +static void sqlite3SelectExpand(Parse *pParse, Select *pSelect){ + Walker w; + w.xSelectCallback = selectExpander; + w.xExprCallback = exprWalkNoop; + w.pParse = pParse; + sqlite3WalkSelect(&w, pSelect); +} + + +#ifndef SQLITE_OMIT_SUBQUERY +/* +** This is a Walker.xSelectCallback callback for the sqlite3SelectTypeInfo() +** interface. +** +** For each FROM-clause subquery, add Column.zType and Column.zColl +** information to the Table structure that represents the result set +** of that subquery. +** +** The Table structure that represents the result set was constructed +** by selectExpander() but the type and collation information was omitted +** at that point because identifiers had not yet been resolved. This +** routine is called after identifier resolution. +*/ +static int selectAddSubqueryTypeInfo(Walker *pWalker, Select *p){ + Parse *pParse; + int i; + SrcList *pTabList; + struct SrcList_item *pFrom; + + assert( p->selFlags & SF_Resolved ); + assert( (p->selFlags & SF_HasTypeInfo)==0 ); + p->selFlags |= SF_HasTypeInfo; + pParse = pWalker->pParse; + pTabList = p->pSrc; + for(i=0, pFrom=pTabList->a; i<pTabList->nSrc; i++, pFrom++){ + Table *pTab = pFrom->pTab; + if( ALWAYS(pTab!=0) && (pTab->tabFlags & TF_Ephemeral)!=0 ){ + /* A sub-query in the FROM clause of a SELECT */ + Select *pSel = pFrom->pSelect; + assert( pSel ); + while( pSel->pPrior ) pSel = pSel->pPrior; + selectAddColumnTypeAndCollation(pParse, pTab->nCol, pTab->aCol, pSel); } } + return WRC_Continue; +} +#endif - /* If this is one SELECT of a compound, be sure to resolve names - ** in the other SELECTs. - */ - if( p->pPrior ){ - return sqlite3SelectResolve(pParse, p->pPrior, pOuterNC); - }else{ - return SQLITE_OK; - } + +/* +** This routine adds datatype and collating sequence information to +** the Table structures of all FROM-clause subqueries in a +** SELECT statement. +** +** Use this routine after name resolution. +*/ +static void sqlite3SelectAddTypeInfo(Parse *pParse, Select *pSelect){ +#ifndef SQLITE_OMIT_SUBQUERY + Walker w; + w.xSelectCallback = selectAddSubqueryTypeInfo; + w.xExprCallback = exprWalkNoop; + w.pParse = pParse; + sqlite3WalkSelect(&w, pSelect); +#endif +} + + +/* +** This routine sets of a SELECT statement for processing. The +** following is accomplished: +** +** * VDBE Cursor numbers are assigned to all FROM-clause terms. +** * Ephemeral Table objects are created for all FROM-clause subqueries. +** * ON and USING clauses are shifted into WHERE statements +** * Wildcards "*" and "TABLE.*" in result sets are expanded. +** * Identifiers in expression are matched to tables. +** +** This routine acts recursively on all subqueries within the SELECT. +*/ +void sqlite3SelectPrep( + Parse *pParse, /* The parser context */ + Select *p, /* The SELECT statement being coded. */ + NameContext *pOuterNC /* Name context for container */ +){ + sqlite3 *db; + if( NEVER(p==0) ) return; + db = pParse->db; + if( p->selFlags & SF_HasTypeInfo ) return; + sqlite3SelectExpand(pParse, p); + if( pParse->nErr || db->mallocFailed ) return; + sqlite3ResolveSelectNames(pParse, p, pOuterNC); + if( pParse->nErr || db->mallocFailed ) return; + sqlite3SelectAddTypeInfo(pParse, p); } /* @@ -3441,12 +3370,13 @@ static void resetAccumulator(Parse *pParse, AggInfo *pAggInfo){ sqlite3VdbeAddOp2(v, OP_Null, 0, pFunc->iMem); if( pFunc->iDistinct>=0 ){ Expr *pE = pFunc->pExpr; - if( pE->pList==0 || pE->pList->nExpr!=1 ){ - sqlite3ErrorMsg(pParse, "DISTINCT in aggregate must be followed " - "by an expression"); + assert( !ExprHasProperty(pE, EP_xIsSelect) ); + if( pE->x.pList==0 || pE->x.pList->nExpr!=1 ){ + sqlite3ErrorMsg(pParse, "DISTINCT aggregates must have exactly one " + "argument"); pFunc->iDistinct = -1; }else{ - KeyInfo *pKeyInfo = keyInfoFromExprList(pParse, pE->pList); + KeyInfo *pKeyInfo = keyInfoFromExprList(pParse, pE->x.pList); sqlite3VdbeAddOp4(v, OP_OpenEphemeral, pFunc->iDistinct, 0, 0, (char*)pKeyInfo, P4_KEYINFO_HANDOFF); } @@ -3463,7 +3393,8 @@ static void finalizeAggFunctions(Parse *pParse, AggInfo *pAggInfo){ int i; struct AggInfo_func *pF; for(i=0, pF=pAggInfo->aFunc; i<pAggInfo->nFunc; i++, pF++){ - ExprList *pList = pF->pExpr->pList; + ExprList *pList = pF->pExpr->x.pList; + assert( !ExprHasProperty(pF->pExpr, EP_xIsSelect) ); sqlite3VdbeAddOp4(v, OP_AggFinal, pF->iMem, pList ? pList->nExpr : 0, 0, (void*)pF->pFunc, P4_FUNCDEF); } @@ -3480,11 +3411,13 @@ static void updateAccumulator(Parse *pParse, AggInfo *pAggInfo){ struct AggInfo_col *pC; pAggInfo->directMode = 1; + sqlite3ExprCacheClear(pParse); for(i=0, pF=pAggInfo->aFunc; i<pAggInfo->nFunc; i++, pF++){ int nArg; int addrNext = 0; int regAgg; - ExprList *pList = pF->pExpr->pList; + ExprList *pList = pF->pExpr->x.pList; + assert( !ExprHasProperty(pF->pExpr, EP_xIsSelect) ); if( pList ){ nArg = pList->nExpr; regAgg = sqlite3GetTempRange(pParse, nArg); @@ -3498,11 +3431,11 @@ static void updateAccumulator(Parse *pParse, AggInfo *pAggInfo){ assert( nArg==1 ); codeDistinct(pParse, pF->iDistinct, addrNext, 1, regAgg); } - if( pF->pFunc->needCollSeq ){ + if( pF->pFunc->flags & SQLITE_FUNC_NEEDCOLL ){ CollSeq *pColl = 0; struct ExprList_item *pItem; int j; - assert( pList!=0 ); /* pList!=0 if pF->pFunc->needCollSeq is true */ + assert( pList!=0 ); /* pList!=0 if pF->pFunc has NEEDCOLL */ for(j=0, pItem=pList->a; !pColl && j<nArg; j++, pItem++){ pColl = sqlite3ExprCollSeq(pParse, pItem->pExpr); } @@ -3513,21 +3446,23 @@ static void updateAccumulator(Parse *pParse, AggInfo *pAggInfo){ } sqlite3VdbeAddOp4(v, OP_AggStep, 0, regAgg, pF->iMem, (void*)pF->pFunc, P4_FUNCDEF); - sqlite3VdbeChangeP5(v, nArg); + sqlite3VdbeChangeP5(v, (u8)nArg); sqlite3ReleaseTempRange(pParse, regAgg, nArg); sqlite3ExprCacheAffinityChange(pParse, regAgg, nArg); if( addrNext ){ sqlite3VdbeResolveLabel(v, addrNext); + sqlite3ExprCacheClear(pParse); } } for(i=0, pC=pAggInfo->aCol; i<pAggInfo->nAccumulator; i++, pC++){ sqlite3ExprCode(pParse, pC->pExpr, pC->iMem); } pAggInfo->directMode = 0; + sqlite3ExprCacheClear(pParse); } /* -** Generate code for the given SELECT statement. +** Generate code for the SELECT statement given in the p argument. ** ** The results are distributed in various ways depending on the ** contents of the SelectDest structure pointed to by argument pDest @@ -3535,33 +3470,43 @@ static void updateAccumulator(Parse *pParse, AggInfo *pAggInfo){ ** ** pDest->eDest Result ** ------------ ------------------------------------------- -** SRT_Callback Invoke the callback for each row of the result. +** SRT_Output Generate a row of output (using the OP_ResultRow +** opcode) for each row in the result set. ** -** SRT_Mem Store first result in memory cell pDest->iParm +** SRT_Mem Only valid if the result is a single column. +** Store the first column of the first result row +** in register pDest->iParm then abandon the rest +** of the query. This destination implies "LIMIT 1". ** -** SRT_Set Store results as keys of table pDest->iParm. -** Apply the affinity pDest->affinity before storing them. +** SRT_Set The result must be a single column. Store each +** row of result as the key in table pDest->iParm. +** Apply the affinity pDest->affinity before storing +** results. Used to implement "IN (SELECT ...)". ** ** SRT_Union Store results as a key in a temporary table pDest->iParm. ** ** SRT_Except Remove results from the temporary table pDest->iParm. ** -** SRT_Table Store results in temporary table pDest->iParm +** SRT_Table Store results in temporary table pDest->iParm. +** This is like SRT_EphemTab except that the table +** is assumed to already be open. ** ** SRT_EphemTab Create an temporary table pDest->iParm and store ** the result there. The cursor is left open after -** returning. +** returning. This is like SRT_Table except that +** this destination uses OP_OpenEphemeral to create +** the table first. ** -** SRT_Coroutine Invoke a co-routine to compute a single row of -** the result +** SRT_Coroutine Generate a co-routine that returns a new row of +** results each time it is invoked. The entry point +** of the co-routine is stored in register pDest->iParm. ** ** SRT_Exists Store a 1 in memory cell pDest->iParm if the result ** set is not empty. ** -** SRT_Discard Throw the results away. -** -** See the selectInnerLoop() function for a canonical listing of the -** allowed values of eDest and their meanings. +** SRT_Discard Throw the results away. This is used by SELECT +** statements within triggers whose only purpose is +** the side-effects of functions. ** ** This routine returns the number of errors. If any errors are ** encountered, then an appropriate error message is left in @@ -3569,35 +3514,11 @@ static void updateAccumulator(Parse *pParse, AggInfo *pAggInfo){ ** ** This routine does NOT free the Select structure passed in. The ** calling function needs to do that. -** -** The pParent, parentTab, and *pParentAgg fields are filled in if this -** SELECT is a subquery. This routine may try to combine this SELECT -** with its parent to form a single flat query. In so doing, it might -** change the parent query from a non-aggregate to an aggregate query. -** For that reason, the pParentAgg flag is passed as a pointer, so it -** can be changed. -** -** Example 1: The meaning of the pParent parameter. -** -** SELECT * FROM t1 JOIN (SELECT x, count(*) FROM t2) JOIN t3; -** \ \_______ subquery _______/ / -** \ / -** \____________________ outer query ___________________/ -** -** This routine is called for the outer query first. For that call, -** pParent will be NULL. During the processing of the outer query, this -** routine is called recursively to handle the subquery. For the recursive -** call, pParent will point to the outer query. Because the subquery is -** the second element in a three-way join, the parentTab parameter will -** be 1 (the 2nd value of a 0-indexed array.) */ int sqlite3Select( Parse *pParse, /* The parser context */ Select *p, /* The SELECT statement being coded. */ - SelectDest *pDest, /* What to do with the query results */ - Select *pParent, /* Another SELECT for which this is a sub-query */ - int parentTab, /* Index in pParent->pSrc of this query */ - int *pParentAgg /* True if pParent uses aggregate functions */ + SelectDest *pDest /* What to do with the query results */ ){ int i, j; /* Loop counters */ WhereInfo *pWInfo; /* Return from sqlite3WhereBegin() */ @@ -3624,41 +3545,24 @@ int sqlite3Select( if( sqlite3AuthCheck(pParse, SQLITE_SELECT, 0, 0, 0) ) return 1; memset(&sAggInfo, 0, sizeof(sAggInfo)); - pOrderBy = p->pOrderBy; if( IgnorableOrderby(pDest) ){ - p->pOrderBy = 0; - - /* In these cases the DISTINCT operator makes no difference to the - ** results, so remove it if it were specified. - */ assert(pDest->eDest==SRT_Exists || pDest->eDest==SRT_Union || pDest->eDest==SRT_Except || pDest->eDest==SRT_Discard); - p->isDistinct = 0; - } - if( sqlite3SelectResolve(pParse, p, 0) ){ - goto select_end; + /* If ORDER BY makes no difference in the output then neither does + ** DISTINCT so it can be removed too. */ + sqlite3ExprListDelete(db, p->pOrderBy); + p->pOrderBy = 0; + p->selFlags &= ~SF_Distinct; } - p->pOrderBy = pOrderBy; - - - /* Make local copies of the parameters for this query. - */ + sqlite3SelectPrep(pParse, p, 0); + pOrderBy = p->pOrderBy; pTabList = p->pSrc; - isAgg = p->isAgg; pEList = p->pEList; - if( pEList==0 ) goto select_end; - - /* - ** Do not even attempt to generate any code if we have already seen - ** errors before this routine starts. - */ - if( pParse->nErr>0 ) goto select_end; - - /* ORDER BY is ignored for some destinations. - */ - if( IgnorableOrderby(pDest) ){ - pOrderBy = 0; + if( pParse->nErr || db->mallocFailed ){ + goto select_end; } + isAgg = (p->selFlags & SF_Aggregate)!=0; + assert( pEList!=0 ); /* Begin generating code. */ @@ -3673,18 +3577,8 @@ int sqlite3Select( SelectDest dest; Select *pSub = pItem->pSelect; int isAggSub; - char *zName = pItem->zName; if( pSub==0 || pItem->isPopulated ) continue; - if( zName!=0 ){ /* An sql view */ - const char *zSavedAuthContext = pParse->zAuthContext; - pParse->zAuthContext = zName; - rc = sqlite3SelectResolve(pParse, pSub, 0); - pParse->zAuthContext = zSavedAuthContext; - if( rc ){ - goto select_end; - } - } /* Increment Parse.nHeight by the height of the largest expression ** tree refered to by this, the parent select. The child select @@ -3696,17 +3590,20 @@ int sqlite3Select( pParse->nHeight += sqlite3SelectExprHeight(p); /* Check to see if the subquery can be absorbed into the parent. */ - isAggSub = pSub->isAgg; + isAggSub = (pSub->selFlags & SF_Aggregate)!=0; if( flattenSubquery(pParse, p, i, isAgg, isAggSub) ){ if( isAggSub ){ - p->isAgg = isAgg = 1; + isAgg = 1; + p->selFlags |= SF_Aggregate; } i = -1; }else{ sqlite3SelectDestInit(&dest, SRT_EphemTab, pItem->iCursor); - sqlite3Select(pParse, pSub, &dest, p, i, &isAgg); + assert( pItem->isPopulated==0 ); + sqlite3Select(pParse, pSub, &dest); + pItem->isPopulated = 1; } - if( pParse->nErr || db->mallocFailed ){ + if( /*pParse->nErr ||*/ db->mallocFailed ){ goto select_end; } pParse->nHeight -= sqlite3SelectExprHeight(p); @@ -3720,7 +3617,7 @@ int sqlite3Select( pWhere = p->pWhere; pGroupBy = p->pGroupBy; pHaving = p->pHaving; - isDistinct = p->isDistinct; + isDistinct = (p->selFlags & SF_Distinct)!=0; #ifndef SQLITE_OMIT_COMPOUND_SELECT /* If there is are a sequence of queries, do the earlier ones first. @@ -3755,12 +3652,13 @@ int sqlite3Select( #endif /* If possible, rewrite the query to use GROUP BY instead of DISTINCT. - ** GROUP BY may use an index, DISTINCT never does. + ** GROUP BY might use an index, DISTINCT never does. */ - if( p->isDistinct && !p->isAgg && !p->pGroupBy ){ - p->pGroupBy = sqlite3ExprListDup(db, p->pEList); + assert( p->pGroupBy==0 || (p->selFlags & SF_Aggregate)!=0 ); + if( (p->selFlags & (SF_Distinct|SF_Aggregate))==SF_Distinct ){ + p->pGroupBy = sqlite3ExprListDup(db, p->pEList, 0); pGroupBy = p->pGroupBy; - p->isDistinct = 0; + p->selFlags &= ~SF_Distinct; isDistinct = 0; } @@ -3843,20 +3741,25 @@ int sqlite3Select( ** processed */ int iAbortFlag; /* Mem address which causes query abort if positive */ int groupBySort; /* Rows come from source in GROUP BY order */ + int addrEnd; /* End of processing for this SELECT */ + /* Remove any and all aliases between the result set and the + ** GROUP BY clause. + */ + if( pGroupBy ){ + int k; /* Loop counter */ + struct ExprList_item *pItem; /* For looping over expression in a list */ - /* The following variables hold addresses or labels for parts of the - ** virtual machine program we are putting together */ - int addrOutputRow; /* Start of subroutine that outputs a result row */ - int regOutputRow; /* Return address register for output subroutine */ - int addrSetAbort; /* Set the abort flag and return */ - int addrInitializeLoop; /* Start of code that initializes the input loop */ - int addrTopOfLoop; /* Top of the input loop */ - int addrEnd; /* End of all processing */ - int addrSortingIdx; /* The OP_OpenEphemeral for the sorting index */ - int addrReset; /* Subroutine for resetting the accumulator */ - int regReset; /* Return address register for reset subroutine */ + for(k=p->pEList->nExpr, pItem=p->pEList->a; k>0; k--, pItem++){ + pItem->iAlias = 0; + } + for(k=pGroupBy->nExpr, pItem=pGroupBy->a; k>0; k--, pItem++){ + pItem->iAlias = 0; + } + } + + /* Create a label to jump to when we want to abort the query */ addrEnd = sqlite3VdbeMakeLabel(v); /* Convert TK_COLUMN nodes into TK_AGG_COLUMN and make entries in @@ -3876,7 +3779,8 @@ int sqlite3Select( } sAggInfo.nAccumulator = sAggInfo.nColumn; for(i=0; i<sAggInfo.nFunc; i++){ - sqlite3ExprAnalyzeAggList(&sNC, sAggInfo.aFunc[i].pExpr->pList); + assert( !ExprHasProperty(sAggInfo.aFunc[i].pExpr, EP_xIsSelect) ); + sqlite3ExprAnalyzeAggList(&sNC, sAggInfo.aFunc[i].pExpr->x.pList); } if( db->mallocFailed ) goto select_end; @@ -3885,11 +3789,14 @@ int sqlite3Select( */ if( pGroupBy ){ KeyInfo *pKeyInfo; /* Keying information for the group by clause */ - int j1; - - /* Create labels that we will be needing - */ - addrInitializeLoop = sqlite3VdbeMakeLabel(v); + int j1; /* A-vs-B comparision jump */ + int addrOutputRow; /* Start of subroutine that outputs a result row */ + int regOutputRow; /* Return address register for output subroutine */ + int addrSetAbort; /* Set the abort flag and return */ + int addrTopOfLoop; /* Top of the input loop */ + int addrSortingIdx; /* The OP_OpenEphemeral for the sorting index */ + int addrReset; /* Subroutine for resetting the accumulator */ + int regReset; /* Return address register for reset subroutine */ /* If there is a GROUP BY clause we might need a sorting index to ** implement it. Allocate that sorting index now. If it turns out @@ -3906,6 +3813,10 @@ int sqlite3Select( */ iUseFlag = ++pParse->nMem; iAbortFlag = ++pParse->nMem; + regOutputRow = ++pParse->nMem; + addrOutputRow = sqlite3VdbeMakeLabel(v); + regReset = ++pParse->nMem; + addrReset = sqlite3VdbeMakeLabel(v); iAMem = pParse->nMem + 1; pParse->nMem += pGroupBy->nExpr; iBMem = pParse->nMem + 1; @@ -3914,47 +3825,12 @@ int sqlite3Select( VdbeComment((v, "clear abort flag")); sqlite3VdbeAddOp2(v, OP_Integer, 0, iUseFlag); VdbeComment((v, "indicate accumulator empty")); - sqlite3VdbeAddOp2(v, OP_Goto, 0, addrInitializeLoop); - - /* Generate a subroutine that outputs a single row of the result - ** set. This subroutine first looks at the iUseFlag. If iUseFlag - ** is less than or equal to zero, the subroutine is a no-op. If - ** the processing calls for the query to abort, this subroutine - ** increments the iAbortFlag memory location before returning in - ** order to signal the caller to abort. - */ - addrSetAbort = sqlite3VdbeCurrentAddr(v); - sqlite3VdbeAddOp2(v, OP_Integer, 1, iAbortFlag); - VdbeComment((v, "set abort flag")); - regOutputRow = ++pParse->nMem; - sqlite3VdbeAddOp1(v, OP_Return, regOutputRow); - addrOutputRow = sqlite3VdbeCurrentAddr(v); - sqlite3VdbeAddOp2(v, OP_IfPos, iUseFlag, addrOutputRow+2); - VdbeComment((v, "Groupby result generator entry point")); - sqlite3VdbeAddOp1(v, OP_Return, regOutputRow); - finalizeAggFunctions(pParse, &sAggInfo); - if( pHaving ){ - sqlite3ExprIfFalse(pParse, pHaving, addrOutputRow+1, SQLITE_JUMPIFNULL); - } - selectInnerLoop(pParse, p, p->pEList, 0, 0, pOrderBy, - distinct, pDest, - addrOutputRow+1, addrSetAbort); - sqlite3VdbeAddOp1(v, OP_Return, regOutputRow); - VdbeComment((v, "end groupby result generator")); - - /* Generate a subroutine that will reset the group-by accumulator - */ - addrReset = sqlite3VdbeCurrentAddr(v); - regReset = ++pParse->nMem; - resetAccumulator(pParse, &sAggInfo); - sqlite3VdbeAddOp1(v, OP_Return, regReset); /* Begin a loop that will extract all source rows in GROUP BY order. ** This might involve two separate loops with an OP_Sort in between, or ** it might be a single loop that uses an index to extract information ** in the right order to begin with. */ - sqlite3VdbeResolveLabel(v, addrInitializeLoop); sqlite3VdbeAddOp2(v, OP_Gosub, regReset, addrReset); pWInfo = sqlite3WhereBegin(pParse, pTabList, pWhere, &pGroupBy, 0); if( pWInfo==0 ) goto select_end; @@ -3987,6 +3863,7 @@ int sqlite3Select( } } regBase = sqlite3GetTempRange(pParse, nCol); + sqlite3ExprCacheClear(pParse); sqlite3ExprCodeExprList(pParse, pGroupBy, regBase, 0); sqlite3VdbeAddOp2(v, OP_Sequence, sAggInfo.sortingIdx,regBase+nGroupBy); j = nGroupBy+1; @@ -3994,20 +3871,14 @@ int sqlite3Select( struct AggInfo_col *pCol = &sAggInfo.aCol[i]; if( pCol->iSorterColumn>=j ){ int r1 = j + regBase; -#ifndef NDEBUG - int r2 = -#endif - sqlite3ExprCodeGetColumn(pParse, + int r2; + + r2 = sqlite3ExprCodeGetColumn(pParse, pCol->pTab, pCol->iColumn, pCol->iTable, r1, 0); + if( r1!=r2 ){ + sqlite3VdbeAddOp2(v, OP_SCopy, r2, r1); + } j++; - - /* sAggInfo.aCol[] only contains one entry per column. So - ** The reference to pCol->iColumn,pCol->iTable must have been - ** the first reference to that column. Hence, - ** sqliteExprCodeGetColumn is guaranteed to put the result in - ** the column requested. - */ - assert( r1==r2 ); } } regRecord = sqlite3GetTempReg(pParse); @@ -4019,6 +3890,7 @@ int sqlite3Select( sqlite3VdbeAddOp2(v, OP_Sort, sAggInfo.sortingIdx, addrEnd); VdbeComment((v, "GROUP BY sort")); sAggInfo.useSortingIdx = 1; + sqlite3ExprCacheClear(pParse); } /* Evaluate the current GROUP BY terms and store in b0, b1, b2... @@ -4027,6 +3899,7 @@ int sqlite3Select( ** from the previous row currently stored in a0, a1, a2... */ addrTopOfLoop = sqlite3VdbeCurrentAddr(v); + sqlite3ExprCacheClear(pParse); for(j=0; j<pGroupBy->nExpr; j++){ if( groupBySort ){ sqlite3VdbeAddOp3(v, OP_Column, sAggInfo.sortingIdx, j, iBMem+j); @@ -4078,71 +3951,162 @@ int sqlite3Select( */ sqlite3VdbeAddOp2(v, OP_Gosub, regOutputRow, addrOutputRow); VdbeComment((v, "output final row")); - - } /* endif pGroupBy */ - else { - ExprList *pMinMax = 0; - ExprList *pDel = 0; - u8 flag; - /* Check if the query is of one of the following forms: - ** - ** SELECT min(x) FROM ... - ** SELECT max(x) FROM ... - ** - ** If it is, then ask the code in where.c to attempt to sort results - ** as if there was an "ORDER ON x" or "ORDER ON x DESC" clause. - ** If where.c is able to produce results sorted in this order, then - ** add vdbe code to break out of the processing loop after the - ** first iteration (since the first iteration of the loop is - ** guaranteed to operate on the row with the minimum or maximum - ** value of x, the only row required). - ** - ** A special flag must be passed to sqlite3WhereBegin() to slightly - ** modify behaviour as follows: - ** - ** + If the query is a "SELECT min(x)", then the loop coded by - ** where.c should not iterate over any values with a NULL value - ** for x. - ** - ** + The optimizer code in where.c (the thing that decides which - ** index or indices to use) should place a different priority on - ** satisfying the 'ORDER BY' clause than it does in other cases. - ** Refer to code and comments in where.c for details. + /* Jump over the subroutines */ - flag = minMaxQuery(pParse, p); - if( flag ){ - pDel = pMinMax = sqlite3ExprListDup(db, p->pEList->a[0].pExpr->pList); - if( pMinMax && !db->mallocFailed ){ - pMinMax->a[0].sortOrder = flag!=WHERE_ORDERBY_MIN; - pMinMax->a[0].pExpr->op = TK_COLUMN; - } - } + sqlite3VdbeAddOp2(v, OP_Goto, 0, addrEnd); - /* This case runs if the aggregate has no GROUP BY clause. The - ** processing is much simpler since there is only a single row - ** of output. + /* Generate a subroutine that outputs a single row of the result + ** set. This subroutine first looks at the iUseFlag. If iUseFlag + ** is less than or equal to zero, the subroutine is a no-op. If + ** the processing calls for the query to abort, this subroutine + ** increments the iAbortFlag memory location before returning in + ** order to signal the caller to abort. */ + addrSetAbort = sqlite3VdbeCurrentAddr(v); + sqlite3VdbeAddOp2(v, OP_Integer, 1, iAbortFlag); + VdbeComment((v, "set abort flag")); + sqlite3VdbeAddOp1(v, OP_Return, regOutputRow); + sqlite3VdbeResolveLabel(v, addrOutputRow); + addrOutputRow = sqlite3VdbeCurrentAddr(v); + sqlite3VdbeAddOp2(v, OP_IfPos, iUseFlag, addrOutputRow+2); + VdbeComment((v, "Groupby result generator entry point")); + sqlite3VdbeAddOp1(v, OP_Return, regOutputRow); + finalizeAggFunctions(pParse, &sAggInfo); + sqlite3ExprIfFalse(pParse, pHaving, addrOutputRow+1, SQLITE_JUMPIFNULL); + selectInnerLoop(pParse, p, p->pEList, 0, 0, pOrderBy, + distinct, pDest, + addrOutputRow+1, addrSetAbort); + sqlite3VdbeAddOp1(v, OP_Return, regOutputRow); + VdbeComment((v, "end groupby result generator")); + + /* Generate a subroutine that will reset the group-by accumulator + */ + sqlite3VdbeResolveLabel(v, addrReset); resetAccumulator(pParse, &sAggInfo); - pWInfo = sqlite3WhereBegin(pParse, pTabList, pWhere, &pMinMax, flag); - if( pWInfo==0 ){ - sqlite3ExprListDelete(db, pDel); - goto select_end; - } - updateAccumulator(pParse, &sAggInfo); - if( !pMinMax && flag ){ - sqlite3VdbeAddOp2(v, OP_Goto, 0, pWInfo->iBreak); - VdbeComment((v, "%s() by index",(flag==WHERE_ORDERBY_MIN?"min":"max"))); + sqlite3VdbeAddOp1(v, OP_Return, regReset); + + } /* endif pGroupBy. Begin aggregate queries without GROUP BY: */ + else { + ExprList *pDel = 0; +#ifndef SQLITE_OMIT_BTREECOUNT + Table *pTab; + if( (pTab = isSimpleCount(p, &sAggInfo))!=0 ){ + /* If isSimpleCount() returns a pointer to a Table structure, then + ** the SQL statement is of the form: + ** + ** SELECT count(*) FROM <tbl> + ** + ** where the Table structure returned represents table <tbl>. + ** + ** This statement is so common that it is optimized specially. The + ** OP_Count instruction is executed either on the intkey table that + ** contains the data for table <tbl> or on one of its indexes. It + ** is better to execute the op on an index, as indexes are almost + ** always spread across less pages than their corresponding tables. + */ + const int iDb = sqlite3SchemaToIndex(pParse->db, pTab->pSchema); + const int iCsr = pParse->nTab++; /* Cursor to scan b-tree */ + Index *pIdx; /* Iterator variable */ + KeyInfo *pKeyInfo = 0; /* Keyinfo for scanned index */ + Index *pBest = 0; /* Best index found so far */ + int iRoot = pTab->tnum; /* Root page of scanned b-tree */ + + sqlite3CodeVerifySchema(pParse, iDb); + sqlite3TableLock(pParse, iDb, pTab->tnum, 0, pTab->zName); + + /* Search for the index that has the least amount of columns. If + ** there is such an index, and it has less columns than the table + ** does, then we can assume that it consumes less space on disk and + ** will therefore be cheaper to scan to determine the query result. + ** In this case set iRoot to the root page number of the index b-tree + ** and pKeyInfo to the KeyInfo structure required to navigate the + ** index. + ** + ** In practice the KeyInfo structure will not be used. It is only + ** passed to keep OP_OpenRead happy. + */ + for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){ + if( !pBest || pIdx->nColumn<pBest->nColumn ){ + pBest = pIdx; + } + } + if( pBest && pBest->nColumn<pTab->nCol ){ + iRoot = pBest->tnum; + pKeyInfo = sqlite3IndexKeyinfo(pParse, pBest); + } + + /* Open a read-only cursor, execute the OP_Count, close the cursor. */ + sqlite3VdbeAddOp3(v, OP_OpenRead, iCsr, iRoot, iDb); + if( pKeyInfo ){ + sqlite3VdbeChangeP4(v, -1, (char *)pKeyInfo, P4_KEYINFO_HANDOFF); + } + sqlite3VdbeAddOp2(v, OP_Count, iCsr, sAggInfo.aFunc[0].iMem); + sqlite3VdbeAddOp1(v, OP_Close, iCsr); + }else +#endif /* SQLITE_OMIT_BTREECOUNT */ + { + /* Check if the query is of one of the following forms: + ** + ** SELECT min(x) FROM ... + ** SELECT max(x) FROM ... + ** + ** If it is, then ask the code in where.c to attempt to sort results + ** as if there was an "ORDER ON x" or "ORDER ON x DESC" clause. + ** If where.c is able to produce results sorted in this order, then + ** add vdbe code to break out of the processing loop after the + ** first iteration (since the first iteration of the loop is + ** guaranteed to operate on the row with the minimum or maximum + ** value of x, the only row required). + ** + ** A special flag must be passed to sqlite3WhereBegin() to slightly + ** modify behaviour as follows: + ** + ** + If the query is a "SELECT min(x)", then the loop coded by + ** where.c should not iterate over any values with a NULL value + ** for x. + ** + ** + The optimizer code in where.c (the thing that decides which + ** index or indices to use) should place a different priority on + ** satisfying the 'ORDER BY' clause than it does in other cases. + ** Refer to code and comments in where.c for details. + */ + ExprList *pMinMax = 0; + u8 flag = minMaxQuery(p); + if( flag ){ + assert( !ExprHasProperty(p->pEList->a[0].pExpr, EP_xIsSelect) ); + pMinMax = sqlite3ExprListDup(db, p->pEList->a[0].pExpr->x.pList,0); + pDel = pMinMax; + if( pMinMax && !db->mallocFailed ){ + pMinMax->a[0].sortOrder = flag!=WHERE_ORDERBY_MIN ?1:0; + pMinMax->a[0].pExpr->op = TK_COLUMN; + } + } + + /* This case runs if the aggregate has no GROUP BY clause. The + ** processing is much simpler since there is only a single row + ** of output. + */ + resetAccumulator(pParse, &sAggInfo); + pWInfo = sqlite3WhereBegin(pParse, pTabList, pWhere, &pMinMax, flag); + if( pWInfo==0 ){ + sqlite3ExprListDelete(db, pDel); + goto select_end; + } + updateAccumulator(pParse, &sAggInfo); + if( !pMinMax && flag ){ + sqlite3VdbeAddOp2(v, OP_Goto, 0, pWInfo->iBreak); + VdbeComment((v, "%s() by index", + (flag==WHERE_ORDERBY_MIN?"min":"max"))); + } + sqlite3WhereEnd(pWInfo); + finalizeAggFunctions(pParse, &sAggInfo); } - sqlite3WhereEnd(pWInfo); - finalizeAggFunctions(pParse, &sAggInfo); + pOrderBy = 0; - if( pHaving ){ - sqlite3ExprIfFalse(pParse, pHaving, addrEnd, SQLITE_JUMPIFNULL); - } + sqlite3ExprIfFalse(pParse, pHaving, addrEnd, SQLITE_JUMPIFNULL); selectInnerLoop(pParse, p, p->pEList, 0, 0, 0, -1, pDest, addrEnd, addrEnd); - sqlite3ExprListDelete(db, pDel); } sqlite3VdbeResolveLabel(v, addrEnd); @@ -4156,19 +4120,6 @@ int sqlite3Select( generateSortTail(pParse, p, v, pEList->nExpr, pDest); } -#ifndef SQLITE_OMIT_SUBQUERY - /* If this was a subquery, we have now converted the subquery into a - ** temporary table. So set the SrcList_item.isPopulated flag to prevent - ** this subquery from being evaluated again and to force the use of - ** the temporary table. - */ - if( pParent ){ - assert( pParent->pSrc->nSrc>parentTab ); - assert( pParent->pSrc->a[parentTab].pSelect==p ); - pParent->pSrc->a[parentTab].isPopulated = 1; - } -#endif - /* Jump here to skip this query */ sqlite3VdbeResolveLabel(v, iEnd); @@ -4183,10 +4134,9 @@ int sqlite3Select( */ select_end: - /* Identify column names if we will be using them in a callback. This - ** step is skipped if the output is going to some other destination. + /* Identify column names if results of the SELECT are to be output. */ - if( rc==SQLITE_OK && pDest->eDest==SRT_Callback ){ + if( rc==SQLITE_OK && pDest->eDest==SRT_Output ){ generateColumnNames(pParse, pTabList, pEList); } @@ -4211,8 +4161,8 @@ select_end: ** or from temporary "printf" statements inserted for debugging. */ void sqlite3PrintExpr(Expr *p){ - if( p->token.z && p->token.n>0 ){ - sqlite3DebugPrintf("(%.*s", p->token.n, p->token.z); + if( !ExprHasProperty(p, EP_IntValue) && p->u.zToken ){ + sqlite3DebugPrintf("(%s", p->u.zToken); }else{ sqlite3DebugPrintf("(%d", p->op); } |