diff options
Diffstat (limited to 'src/select.c')
| -rw-r--r-- | src/select.c | 3879 |
1 files changed, 2794 insertions, 1085 deletions
diff --git a/src/select.c b/src/select.c index 42474d61d..2b28d9ca5 100644 --- a/src/select.c +++ b/src/select.c @@ -21,7 +21,7 @@ */ typedef struct DistinctCtx DistinctCtx; struct DistinctCtx { - u8 isTnct; /* True if the DISTINCT keyword is present */ + u8 isTnct; /* 0: Not distinct. 1: DISTICT 2: DISTINCT and ORDER BY */ u8 eTnctType; /* One of the WHERE_DISTINCT_* operators */ int tabTnct; /* Ephemeral table used for DISTINCT processing */ int addrTnct; /* Address of OP_OpenEphemeral opcode for tabTnct */ @@ -65,6 +65,10 @@ struct SortCtx { } aDefer[4]; #endif struct RowLoadInfo *pDeferredRowLoad; /* Deferred row loading info or NULL */ +#ifdef SQLITE_ENABLE_STMT_SCANSTATUS + int addrPush; /* First instruction to push data into sorter */ + int addrPushEnd; /* Last instruction that pushes data into sorter */ +#endif }; #define SORTFLAG_UseSorter 0x01 /* Use SorterOpen instead of OpenEphemeral */ @@ -76,6 +80,7 @@ struct SortCtx { ** If bFree==0, Leave the first Select object unfreed */ static void clearSelect(sqlite3 *db, Select *p, int bFree){ + assert( db!=0 ); while( p ){ Select *pPrior = p->pPrior; sqlite3ExprListDelete(db, p->pEList); @@ -85,13 +90,17 @@ static void clearSelect(sqlite3 *db, Select *p, int bFree){ sqlite3ExprDelete(db, p->pHaving); sqlite3ExprListDelete(db, p->pOrderBy); sqlite3ExprDelete(db, p->pLimit); + if( OK_IF_ALWAYS_TRUE(p->pWith) ) sqlite3WithDelete(db, p->pWith); #ifndef SQLITE_OMIT_WINDOWFUNC if( OK_IF_ALWAYS_TRUE(p->pWinDefn) ){ sqlite3WindowListDelete(db, p->pWinDefn); } + while( p->pWin ){ + assert( p->pWin->ppThis==&p->pWin ); + sqlite3WindowUnlinkFromSelect(p->pWin); + } #endif - if( OK_IF_ALWAYS_TRUE(p->pWith) ) sqlite3WithDelete(db, p->pWith); - if( bFree ) sqlite3DbFreeNN(db, p); + if( bFree ) sqlite3DbNNFreeNN(db, p); p = pPrior; bFree = 1; } @@ -103,6 +112,7 @@ static void clearSelect(sqlite3 *db, Select *p, int bFree){ void sqlite3SelectDestInit(SelectDest *pDest, int eDest, int iParm){ pDest->eDest = (u8)eDest; pDest->iSDParm = iParm; + pDest->iSDParm2 = 0; pDest->zAffSdst = 0; pDest->iSdst = 0; pDest->nSdst = 0; @@ -176,21 +186,6 @@ void sqlite3SelectDelete(sqlite3 *db, Select *p){ } /* -** Delete all the substructure for p, but keep p allocated. Redefine -** p to be a single SELECT where every column of the result set has a -** value of NULL. -*/ -void sqlite3SelectReset(Parse *pParse, Select *p){ - if( ALWAYS(p) ){ - clearSelect(pParse->db, p, 0); - memset(&p->iLimit, 0, sizeof(Select) - offsetof(Select,iLimit)); - p->pEList = sqlite3ExprListAppend(pParse, 0, - sqlite3ExprAlloc(pParse->db,TK_NULL,0,0)); - p->pSrc = sqlite3DbMallocZero(pParse->db, sizeof(SrcList)); - } -} - -/* ** Return a pointer to the right-most SELECT statement in a compound. */ static Select *findRightmost(Select *p){ @@ -214,6 +209,52 @@ static Select *findRightmost(Select *p){ ** ** If an illegal or unsupported join type is seen, then still return ** a join type, but put an error in the pParse structure. +** +** These are the valid join types: +** +** +** pA pB pC Return Value +** ------- ----- ----- ------------ +** CROSS - - JT_CROSS +** INNER - - JT_INNER +** LEFT - - JT_LEFT|JT_OUTER +** LEFT OUTER - JT_LEFT|JT_OUTER +** RIGHT - - JT_RIGHT|JT_OUTER +** RIGHT OUTER - JT_RIGHT|JT_OUTER +** FULL - - JT_LEFT|JT_RIGHT|JT_OUTER +** FULL OUTER - JT_LEFT|JT_RIGHT|JT_OUTER +** NATURAL INNER - JT_NATURAL|JT_INNER +** NATURAL LEFT - JT_NATURAL|JT_LEFT|JT_OUTER +** NATURAL LEFT OUTER JT_NATURAL|JT_LEFT|JT_OUTER +** NATURAL RIGHT - JT_NATURAL|JT_RIGHT|JT_OUTER +** NATURAL RIGHT OUTER JT_NATURAL|JT_RIGHT|JT_OUTER +** NATURAL FULL - JT_NATURAL|JT_LEFT|JT_RIGHT +** NATURAL FULL OUTER JT_NATRUAL|JT_LEFT|JT_RIGHT +** +** To preserve historical compatibly, SQLite also accepts a variety +** of other non-standard and in many cases nonsensical join types. +** This routine makes as much sense at it can from the nonsense join +** type and returns a result. Examples of accepted nonsense join types +** include but are not limited to: +** +** INNER CROSS JOIN -> same as JOIN +** NATURAL CROSS JOIN -> same as NATURAL JOIN +** OUTER LEFT JOIN -> same as LEFT JOIN +** LEFT NATURAL JOIN -> same as NATURAL LEFT JOIN +** LEFT RIGHT JOIN -> same as FULL JOIN +** RIGHT OUTER FULL JOIN -> same as FULL JOIN +** CROSS CROSS CROSS JOIN -> same as JOIN +** +** The only restrictions on the join type name are: +** +** * "INNER" cannot appear together with "OUTER", "LEFT", "RIGHT", +** or "FULL". +** +** * "CROSS" cannot appear together with "OUTER", "LEFT", "RIGHT, +** or "FULL". +** +** * If "OUTER" is present then there must also be one of +** "LEFT", "RIGHT", or "FULL" */ int sqlite3JoinType(Parse *pParse, Token *pA, Token *pB, Token *pC){ int jointype = 0; @@ -226,13 +267,13 @@ int sqlite3JoinType(Parse *pParse, Token *pA, Token *pB, Token *pC){ 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 }, + /* (0) natural */ { 0, 7, JT_NATURAL }, + /* (1) left */ { 6, 4, JT_LEFT|JT_OUTER }, + /* (2) outer */ { 10, 5, JT_OUTER }, + /* (3) right */ { 14, 5, JT_RIGHT|JT_OUTER }, + /* (4) full */ { 19, 4, JT_LEFT|JT_RIGHT|JT_OUTER }, + /* (5) inner */ { 23, 5, JT_INNER }, + /* (6) cross */ { 28, 5, JT_INNER|JT_CROSS }, }; int i, j; apAll[0] = pA; @@ -241,7 +282,7 @@ int sqlite3JoinType(Parse *pParse, Token *pA, Token *pB, Token *pC){ for(i=0; i<3 && apAll[i]; i++){ p = apAll[i]; for(j=0; j<ArraySize(aKeyword); j++){ - if( p->n==aKeyword[j].nChar + if( p->n==aKeyword[j].nChar && sqlite3StrNICmp((char*)p->z, &zKeyText[aKeyword[j].i], p->n)==0 ){ jointype |= aKeyword[j].code; break; @@ -255,18 +296,15 @@ int sqlite3JoinType(Parse *pParse, Token *pA, Token *pB, Token *pC){ } if( (jointype & (JT_INNER|JT_OUTER))==(JT_INNER|JT_OUTER) || - (jointype & JT_ERROR)!=0 + (jointype & JT_ERROR)!=0 || + (jointype & (JT_OUTER|JT_LEFT|JT_RIGHT))==JT_OUTER ){ - const char *zSp = " "; - assert( pB!=0 ); - if( pC==0 ){ zSp++; } - sqlite3ErrorMsg(pParse, "unknown or unsupported join type: " - "%T %T%s%T", pA, pB, zSp, pC); - jointype = JT_INNER; - }else if( (jointype & JT_OUTER)!=0 - && (jointype & (JT_LEFT|JT_RIGHT))!=JT_LEFT ){ - sqlite3ErrorMsg(pParse, - "RIGHT and FULL OUTER JOINs are not currently supported"); + const char *zSp1 = " "; + const char *zSp2 = " "; + if( pB==0 ){ zSp1++; } + if( pC==0 ){ zSp2++; } + sqlite3ErrorMsg(pParse, "unknown join type: " + "%T%s%T%s%T", pA, zSp1, pB, zSp2, pC); jointype = JT_INNER; } return jointype; @@ -276,17 +314,36 @@ int sqlite3JoinType(Parse *pParse, Token *pA, Token *pB, Token *pC){ ** Return the index of a column in a table. Return -1 if the column ** is not contained in the table. */ -static int columnIndex(Table *pTab, const char *zCol){ +int sqlite3ColumnIndex(Table *pTab, const char *zCol){ int i; - for(i=0; i<pTab->nCol; i++){ - if( sqlite3StrICmp(pTab->aCol[i].zName, zCol)==0 ) return i; + u8 h = sqlite3StrIHash(zCol); + Column *pCol; + for(pCol=pTab->aCol, i=0; i<pTab->nCol; pCol++, i++){ + if( pCol->hName==h && sqlite3StrICmp(pCol->zCnName, zCol)==0 ) return i; } return -1; } /* -** Search the first N tables in pSrc, from left to right, looking for a -** table that has a column named zCol. +** Mark a subquery result column as having been used. +*/ +void sqlite3SrcItemColumnUsed(SrcItem *pItem, int iCol){ + assert( pItem!=0 ); + assert( (int)pItem->fg.isNestedFrom == IsNestedFrom(pItem->pSelect) ); + if( pItem->fg.isNestedFrom ){ + ExprList *pResults; + assert( pItem->pSelect!=0 ); + pResults = pItem->pSelect->pEList; + assert( pResults!=0 ); + assert( iCol>=0 && iCol<pResults->nExpr ); + pResults->a[iCol].fg.bUsed = 1; + } +} + +/* +** Search the tables iStart..iEnd (inclusive) in pSrc, looking for a +** table that has a column named zCol. The search is left-to-right. +** The first match found is returned. ** ** When found, set *piTab and *piCol to the table index and column index ** of the matching column and return TRUE. @@ -295,22 +352,27 @@ static int columnIndex(Table *pTab, const char *zCol){ */ static int tableAndColumnIndex( SrcList *pSrc, /* Array of tables to search */ - int N, /* Number of tables in pSrc->a[] to search */ + int iStart, /* First member of pSrc->a[] to check */ + int iEnd, /* Last member of pSrc->a[] to check */ const char *zCol, /* Name of the column we are looking for */ int *piTab, /* Write index of pSrc->a[] here */ int *piCol, /* Write index of pSrc->a[*piTab].pTab->aCol[] here */ - int bIgnoreHidden /* True to ignore hidden columns */ + int bIgnoreHidden /* Ignore hidden columns */ ){ int i; /* For looping over tables in pSrc */ int iCol; /* Index of column matching zCol */ + assert( iEnd<pSrc->nSrc ); + assert( iStart>=0 ); assert( (piTab==0)==(piCol==0) ); /* Both or neither are NULL */ - for(i=0; i<N; i++){ - iCol = columnIndex(pSrc->a[i].pTab, zCol); - if( iCol>=0 + + for(i=iStart; i<=iEnd; i++){ + iCol = sqlite3ColumnIndex(pSrc->a[i].pTab, zCol); + if( iCol>=0 && (bIgnoreHidden==0 || IsHiddenColumn(&pSrc->a[i].pTab->aCol[iCol])==0) ){ if( piTab ){ + sqlite3SrcItemColumnUsed(&pSrc->a[i], iCol); *piTab = i; *piCol = iCol; } @@ -321,63 +383,19 @@ static int tableAndColumnIndex( } /* -** This function is used to add terms implied by JOIN syntax to the -** WHERE clause expression of a SELECT statement. The new term, which -** is ANDed with the existing WHERE clause, is of the form: -** -** (tab1.col1 = tab2.col2) -** -** where tab1 is the iSrc'th table in SrcList pSrc and tab2 is the -** (iSrc+1)'th. Column col1 is column iColLeft of tab1, and col2 is -** column iColRight of tab2. -*/ -static void addWhereTerm( - Parse *pParse, /* Parsing context */ - SrcList *pSrc, /* List of tables in FROM clause */ - int iLeft, /* Index of first table to join in pSrc */ - int iColLeft, /* Index of column in first table */ - int iRight, /* Index of second table in pSrc */ - int iColRight, /* Index of column in second table */ - int isOuterJoin, /* True if this is an OUTER join */ - Expr **ppWhere /* IN/OUT: The WHERE clause to add to */ -){ - sqlite3 *db = pParse->db; - Expr *pE1; - Expr *pE2; - Expr *pEq; - - assert( iLeft<iRight ); - assert( pSrc->nSrc>iRight ); - assert( pSrc->a[iLeft].pTab ); - assert( pSrc->a[iRight].pTab ); - - pE1 = sqlite3CreateColumnExpr(db, pSrc, iLeft, iColLeft); - pE2 = sqlite3CreateColumnExpr(db, pSrc, iRight, iColRight); - - pEq = sqlite3PExpr(pParse, TK_EQ, pE1, pE2); - if( pEq && isOuterJoin ){ - ExprSetProperty(pEq, EP_FromJoin); - assert( !ExprHasProperty(pEq, EP_TokenOnly|EP_Reduced) ); - ExprSetVVAProperty(pEq, EP_NoReduce); - pEq->iRightJoinTable = (i16)pE2->iTable; - } - *ppWhere = sqlite3ExprAnd(pParse, *ppWhere, pEq); -} - -/* -** Set the EP_FromJoin property on all terms of the given expression. -** And set the Expr.iRightJoinTable to iTable for every term in the +** Set the EP_OuterON property on all terms of the given expression. +** And set the Expr.w.iJoin to iTable for every term in the ** expression. ** -** The EP_FromJoin property is used on terms of an expression to tell -** the LEFT OUTER JOIN processing logic that this term is part of the +** The EP_OuterON property is used on terms of an expression to tell +** the OUTER JOIN processing logic that this term is part of the ** join restriction specified in the ON or USING clause and not a part ** of the more general WHERE clause. These terms are moved over to the ** WHERE clause during join processing but we need to remember that they ** originated in the ON or USING clause. ** -** The Expr.iRightJoinTable tells the WHERE clause processing that the -** expression depends on table iRightJoinTable even if that table is not +** The Expr.w.iJoin tells the WHERE clause processing that the +** expression depends on table w.iJoin even if that table is not ** explicitly mentioned in the expression. That information is needed ** for cases like this: ** @@ -390,144 +408,223 @@ static void addWhereTerm( ** after the t1 loop and rows with t1.x!=5 will never appear in ** the output, which is incorrect. */ -void sqlite3SetJoinExpr(Expr *p, int iTable){ +void sqlite3SetJoinExpr(Expr *p, int iTable, u32 joinFlag){ + assert( joinFlag==EP_OuterON || joinFlag==EP_InnerON ); while( p ){ - ExprSetProperty(p, EP_FromJoin); + ExprSetProperty(p, joinFlag); assert( !ExprHasProperty(p, EP_TokenOnly|EP_Reduced) ); ExprSetVVAProperty(p, EP_NoReduce); - p->iRightJoinTable = (i16)iTable; - if( p->op==TK_FUNCTION && p->x.pList ){ - int i; - for(i=0; i<p->x.pList->nExpr; i++){ - sqlite3SetJoinExpr(p->x.pList->a[i].pExpr, iTable); + p->w.iJoin = iTable; + if( p->op==TK_FUNCTION ){ + assert( ExprUseXList(p) ); + if( p->x.pList ){ + int i; + for(i=0; i<p->x.pList->nExpr; i++){ + sqlite3SetJoinExpr(p->x.pList->a[i].pExpr, iTable, joinFlag); + } } } - sqlite3SetJoinExpr(p->pLeft, iTable); + sqlite3SetJoinExpr(p->pLeft, iTable, joinFlag); p = p->pRight; - } + } } -/* Undo the work of sqlite3SetJoinExpr(). In the expression p, convert every -** term that is marked with EP_FromJoin and iRightJoinTable==iTable into -** an ordinary term that omits the EP_FromJoin mark. +/* Undo the work of sqlite3SetJoinExpr(). This is used when a LEFT JOIN +** is simplified into an ordinary JOIN, and when an ON expression is +** "pushed down" into the WHERE clause of a subquery. +** +** Convert every term that is marked with EP_OuterON and w.iJoin==iTable into +** an ordinary term that omits the EP_OuterON mark. Or if iTable<0, then +** just clear every EP_OuterON and EP_InnerON mark from the expression tree. ** -** This happens when a LEFT JOIN is simplified into an ordinary JOIN. +** If nullable is true, that means that Expr p might evaluate to NULL even +** if it is a reference to a NOT NULL column. This can happen, for example, +** if the table that p references is on the left side of a RIGHT JOIN. +** If nullable is true, then take care to not remove the EP_CanBeNull bit. +** See forum thread https://sqlite.org/forum/forumpost/b40696f50145d21c */ -static void unsetJoinExpr(Expr *p, int iTable){ +static void unsetJoinExpr(Expr *p, int iTable, int nullable){ while( p ){ - if( ExprHasProperty(p, EP_FromJoin) - && (iTable<0 || p->iRightJoinTable==iTable) ){ - ExprClearProperty(p, EP_FromJoin); - } - if( p->op==TK_FUNCTION && p->x.pList ){ - int i; - for(i=0; i<p->x.pList->nExpr; i++){ - unsetJoinExpr(p->x.pList->a[i].pExpr, iTable); + if( iTable<0 || (ExprHasProperty(p, EP_OuterON) && p->w.iJoin==iTable) ){ + ExprClearProperty(p, EP_OuterON|EP_InnerON); + if( iTable>=0 ) ExprSetProperty(p, EP_InnerON); + } + if( p->op==TK_COLUMN && p->iTable==iTable && !nullable ){ + ExprClearProperty(p, EP_CanBeNull); + } + if( p->op==TK_FUNCTION ){ + assert( ExprUseXList(p) ); + assert( p->pLeft==0 ); + if( p->x.pList ){ + int i; + for(i=0; i<p->x.pList->nExpr; i++){ + unsetJoinExpr(p->x.pList->a[i].pExpr, iTable, nullable); + } } } - unsetJoinExpr(p->pLeft, iTable); + unsetJoinExpr(p->pLeft, iTable, nullable); p = p->pRight; - } + } } /* ** This routine processes the join information for a SELECT statement. -** ON and USING clauses are converted into extra terms of the WHERE clause. -** NATURAL joins also create extra WHERE clause terms. +** +** * A NATURAL join is converted into a USING join. After that, we +** do not need to be concerned with NATURAL joins and we only have +** think about USING joins. +** +** * ON and USING clauses result in extra terms being added to the +** WHERE clause to enforce the specified constraints. The extra +** WHERE clause terms will be tagged with EP_OuterON or +** EP_InnerON so that we know that they originated in ON/USING. ** ** The terms of a FROM clause are contained in the Select.pSrc structure. ** The left most table is the first entry in Select.pSrc. The right-most ** table is the last entry. The join operator is held in the entry to -** the left. Thus entry 0 contains the join operator for the join between +** the right. Thus entry 1 contains the join operator for the join between ** entries 0 and 1. Any ON or USING clauses associated with the join are -** also attached to the left entry. +** also attached to the right entry. ** ** This routine returns the number of errors encountered. */ -static int sqliteProcessJoin(Parse *pParse, Select *p){ +static int sqlite3ProcessJoin(Parse *pParse, Select *p){ SrcList *pSrc; /* All tables in the FROM clause */ int i, j; /* Loop counters */ - struct SrcList_item *pLeft; /* Left table being joined */ - struct SrcList_item *pRight; /* Right table being joined */ + SrcItem *pLeft; /* Left table being joined */ + SrcItem *pRight; /* Right table being joined */ pSrc = p->pSrc; pLeft = &pSrc->a[0]; pRight = &pLeft[1]; for(i=0; i<pSrc->nSrc-1; i++, pRight++, pLeft++){ Table *pRightTab = pRight->pTab; - int isOuter; + u32 joinType; if( NEVER(pLeft->pTab==0 || pRightTab==0) ) continue; - isOuter = (pRight->fg.jointype & JT_OUTER)!=0; + joinType = (pRight->fg.jointype & JT_OUTER)!=0 ? EP_OuterON : EP_InnerON; - /* When the NATURAL keyword is present, add WHERE clause terms for - ** every column that the two tables have in common. + /* If this is a NATURAL join, synthesize an appropriate USING clause + ** to specify which columns should be joined. */ if( pRight->fg.jointype & JT_NATURAL ){ - if( pRight->pOn || pRight->pUsing ){ + IdList *pUsing = 0; + if( pRight->fg.isUsing || pRight->u3.pOn ){ sqlite3ErrorMsg(pParse, "a NATURAL join may not have " "an ON or USING clause", 0); return 1; } for(j=0; j<pRightTab->nCol; j++){ char *zName; /* Name of column in the right table */ - int iLeft; /* Matching left table */ - int iLeftCol; /* Matching column in the left table */ if( IsHiddenColumn(&pRightTab->aCol[j]) ) continue; - zName = pRightTab->aCol[j].zName; - if( tableAndColumnIndex(pSrc, i+1, zName, &iLeft, &iLeftCol, 1) ){ - addWhereTerm(pParse, pSrc, iLeft, iLeftCol, i+1, j, - isOuter, &p->pWhere); + zName = pRightTab->aCol[j].zCnName; + if( tableAndColumnIndex(pSrc, 0, i, zName, 0, 0, 1) ){ + pUsing = sqlite3IdListAppend(pParse, pUsing, 0); + if( pUsing ){ + assert( pUsing->nId>0 ); + assert( pUsing->a[pUsing->nId-1].zName==0 ); + pUsing->a[pUsing->nId-1].zName = sqlite3DbStrDup(pParse->db, zName); + } } } - } - - /* Disallow both ON and USING clauses in the same join - */ - if( pRight->pOn && pRight->pUsing ){ - sqlite3ErrorMsg(pParse, "cannot have both ON and USING " - "clauses in the same join"); - return 1; - } - - /* Add the ON clause to the end of the WHERE clause, connected by - ** an AND operator. - */ - if( pRight->pOn ){ - if( isOuter ) sqlite3SetJoinExpr(pRight->pOn, pRight->iCursor); - p->pWhere = sqlite3ExprAnd(pParse, p->pWhere, pRight->pOn); - pRight->pOn = 0; + if( pUsing ){ + pRight->fg.isUsing = 1; + pRight->fg.isSynthUsing = 1; + pRight->u3.pUsing = pUsing; + } + if( pParse->nErr ) return 1; } /* Create extra terms on the WHERE clause for each column named - ** in the USING clause. Example: If the two tables to be joined are + ** in the USING clause. Example: If the two tables to be joined are ** A and B and the USING clause names X, Y, and Z, then add this ** to the WHERE clause: A.X=B.X AND A.Y=B.Y AND A.Z=B.Z ** Report an error if any column mentioned in the USING clause is ** not contained in both tables to be joined. */ - if( pRight->pUsing ){ - IdList *pList = pRight->pUsing; + if( pRight->fg.isUsing ){ + IdList *pList = pRight->u3.pUsing; + sqlite3 *db = pParse->db; + assert( pList!=0 ); for(j=0; j<pList->nId; j++){ char *zName; /* Name of the term in the USING clause */ int iLeft; /* Table on the left with matching column name */ int iLeftCol; /* Column number of matching column on the left */ int iRightCol; /* Column number of matching column on the right */ + Expr *pE1; /* Reference to the column on the LEFT of the join */ + Expr *pE2; /* Reference to the column on the RIGHT of the join */ + Expr *pEq; /* Equality constraint. pE1 == pE2 */ zName = pList->a[j].zName; - iRightCol = columnIndex(pRightTab, zName); + iRightCol = sqlite3ColumnIndex(pRightTab, zName); if( iRightCol<0 - || !tableAndColumnIndex(pSrc, i+1, zName, &iLeft, &iLeftCol, 0) + || tableAndColumnIndex(pSrc, 0, i, zName, &iLeft, &iLeftCol, + pRight->fg.isSynthUsing)==0 ){ sqlite3ErrorMsg(pParse, "cannot join using column %s - column " "not present in both tables", zName); return 1; } - addWhereTerm(pParse, pSrc, iLeft, iLeftCol, i+1, iRightCol, - isOuter, &p->pWhere); + pE1 = sqlite3CreateColumnExpr(db, pSrc, iLeft, iLeftCol); + sqlite3SrcItemColumnUsed(&pSrc->a[iLeft], iLeftCol); + if( (pSrc->a[0].fg.jointype & JT_LTORJ)!=0 ){ + /* This branch runs if the query contains one or more RIGHT or FULL + ** JOINs. If only a single table on the left side of this join + ** contains the zName column, then this branch is a no-op. + ** But if there are two or more tables on the left side + ** of the join, construct a coalesce() function that gathers all + ** such tables. Raise an error if more than one of those references + ** to zName is not also within a prior USING clause. + ** + ** We really ought to raise an error if there are two or more + ** non-USING references to zName on the left of an INNER or LEFT + ** JOIN. But older versions of SQLite do not do that, so we avoid + ** adding a new error so as to not break legacy applications. + */ + ExprList *pFuncArgs = 0; /* Arguments to the coalesce() */ + static const Token tkCoalesce = { "coalesce", 8 }; + while( tableAndColumnIndex(pSrc, iLeft+1, i, zName, &iLeft, &iLeftCol, + pRight->fg.isSynthUsing)!=0 ){ + if( pSrc->a[iLeft].fg.isUsing==0 + || sqlite3IdListIndex(pSrc->a[iLeft].u3.pUsing, zName)<0 + ){ + sqlite3ErrorMsg(pParse, "ambiguous reference to %s in USING()", + zName); + break; + } + pFuncArgs = sqlite3ExprListAppend(pParse, pFuncArgs, pE1); + pE1 = sqlite3CreateColumnExpr(db, pSrc, iLeft, iLeftCol); + sqlite3SrcItemColumnUsed(&pSrc->a[iLeft], iLeftCol); + } + if( pFuncArgs ){ + pFuncArgs = sqlite3ExprListAppend(pParse, pFuncArgs, pE1); + pE1 = sqlite3ExprFunction(pParse, pFuncArgs, &tkCoalesce, 0); + } + } + pE2 = sqlite3CreateColumnExpr(db, pSrc, i+1, iRightCol); + sqlite3SrcItemColumnUsed(pRight, iRightCol); + pEq = sqlite3PExpr(pParse, TK_EQ, pE1, pE2); + assert( pE2!=0 || pEq==0 ); + if( pEq ){ + ExprSetProperty(pEq, joinType); + assert( !ExprHasProperty(pEq, EP_TokenOnly|EP_Reduced) ); + ExprSetVVAProperty(pEq, EP_NoReduce); + pEq->w.iJoin = pE2->iTable; + } + p->pWhere = sqlite3ExprAnd(pParse, p->pWhere, pEq); } } + + /* Add the ON clause to the end of the WHERE clause, connected by + ** an AND operator. + */ + else if( pRight->u3.pOn ){ + sqlite3SetJoinExpr(pRight->u3.pOn, pRight->iCursor, joinType); + p->pWhere = sqlite3ExprAnd(pParse, p->pWhere, pRight->u3.pOn); + pRight->u3.pOn = 0; + pRight->fg.isOn = 1; + } } return 0; } @@ -621,14 +718,18 @@ static void pushOntoSorter( ** (2) All output columns are included in the sort record. In that ** case regData==regOrigData. ** (3) Some output columns are omitted from the sort record due to - ** the SQLITE_ENABLE_SORTER_REFERENCE optimization, or due to the - ** SQLITE_ECEL_OMITREF optimization, or due to the - ** SortCtx.pDeferredRowLoad optimiation. In any of these cases + ** the SQLITE_ENABLE_SORTER_REFERENCES optimization, or due to the + ** SQLITE_ECEL_OMITREF optimization, or due to the + ** SortCtx.pDeferredRowLoad optimization. In any of these cases ** regOrigData is 0 to prevent this routine from trying to copy ** values that might not yet exist. */ assert( nData==1 || regData==regOrigData || regOrigData==0 ); +#ifdef SQLITE_ENABLE_STMT_SCANSTATUS + pSort->addrPush = sqlite3VdbeCurrentAddr(v); +#endif + if( nPrefixReg ){ assert( nPrefixReg==nExpr+bSeq ); regBase = regData - nPrefixReg; @@ -660,7 +761,7 @@ static void pushOntoSorter( pParse->nMem += pSort->nOBSat; nKey = nExpr - pSort->nOBSat + bSeq; if( bSeq ){ - addrFirst = sqlite3VdbeAddOp1(v, OP_IfNot, regBase+nExpr); + addrFirst = sqlite3VdbeAddOp1(v, OP_IfNot, regBase+nExpr); }else{ addrFirst = sqlite3VdbeAddOp1(v, OP_SequenceTest, pSort->iECursor); } @@ -675,7 +776,7 @@ static void pushOntoSorter( testcase( pKI->nAllField > pKI->nKeyField+2 ); pOp->p4.pKeyInfo = sqlite3KeyInfoFromExprList(pParse,pSort->pOrderBy,nOBSat, pKI->nAllField-pKI->nKeyField-1); - pOp = 0; /* Ensure pOp not used after sqltie3VdbeAddOp3() */ + pOp = 0; /* Ensure pOp not used after sqlite3VdbeAddOp3() */ addrJmp = sqlite3VdbeCurrentAddr(v); sqlite3VdbeAddOp3(v, OP_Jump, addrJmp+1, 0, addrJmp+1); VdbeCoverage(v); pSort->labelBkOut = sqlite3VdbeMakeLabel(pParse); @@ -694,10 +795,10 @@ static void pushOntoSorter( /* At this point the values for the new sorter entry are stored ** in an array of registers. They need to be composed into a record ** and inserted into the sorter if either (a) there are currently - ** less than LIMIT+OFFSET items or (b) the new record is smaller than + ** less than LIMIT+OFFSET items or (b) the new record is smaller than ** the largest record currently in the sorter. If (b) is true and there ** are already LIMIT+OFFSET items in the sorter, delete the largest - ** entry before inserting the new one. This way there are never more + ** entry before inserting the new one. This way there are never more ** than LIMIT+OFFSET items in the sorter. ** ** If the new record does not need to be inserted into the sorter, @@ -729,6 +830,9 @@ static void pushOntoSorter( sqlite3VdbeChangeP2(v, iSkip, pSort->labelOBLopt ? pSort->labelOBLopt : sqlite3VdbeCurrentAddr(v)); } +#ifdef SQLITE_ENABLE_STMT_SCANSTATUS + pSort->addrPushEnd = sqlite3VdbeCurrentAddr(v)-1; +#endif } /* @@ -746,38 +850,164 @@ static void codeOffset( } /* -** Add code that will check to make sure the N registers starting at iMem -** form a distinct entry. iTab is a sorting index that holds previously -** seen combinations of the N values. A new entry is made in iTab -** if the current N values are new. -** -** A jump to addrRepeat is made and the N+1 values are popped from the -** stack if the top N elements are not distinct. +** Add code that will check to make sure the array of registers starting at +** iMem form a distinct entry. This is used by both "SELECT DISTINCT ..." and +** distinct aggregates ("SELECT count(DISTINCT <expr>) ..."). Three strategies +** are available. Which is used depends on the value of parameter eTnctType, +** as follows: +** +** WHERE_DISTINCT_UNORDERED/WHERE_DISTINCT_NOOP: +** Build an ephemeral table that contains all entries seen before and +** skip entries which have been seen before. +** +** Parameter iTab is the cursor number of an ephemeral table that must +** be opened before the VM code generated by this routine is executed. +** The ephemeral cursor table is queried for a record identical to the +** record formed by the current array of registers. If one is found, +** jump to VM address addrRepeat. Otherwise, insert a new record into +** the ephemeral cursor and proceed. +** +** The returned value in this case is a copy of parameter iTab. +** +** WHERE_DISTINCT_ORDERED: +** In this case rows are being delivered sorted order. The ephemeral +** table is not required. Instead, the current set of values +** is compared against previous row. If they match, the new row +** is not distinct and control jumps to VM address addrRepeat. Otherwise, +** the VM program proceeds with processing the new row. +** +** The returned value in this case is the register number of the first +** in an array of registers used to store the previous result row so that +** it can be compared to the next. The caller must ensure that this +** register is initialized to NULL. (The fixDistinctOpenEph() routine +** will take care of this initialization.) +** +** WHERE_DISTINCT_UNIQUE: +** In this case it has already been determined that the rows are distinct. +** No special action is required. The return value is zero. +** +** Parameter pEList is the list of expressions used to generated the +** contents of each row. It is used by this routine to determine (a) +** how many elements there are in the array of registers and (b) the +** collation sequences that should be used for the comparisons if +** eTnctType is WHERE_DISTINCT_ORDERED. */ -static void codeDistinct( +static int codeDistinct( Parse *pParse, /* Parsing and code generating context */ + int eTnctType, /* WHERE_DISTINCT_* value */ int iTab, /* A sorting index used to test for distinctness */ int addrRepeat, /* Jump to here if not distinct */ - int N, /* Number of elements */ - int iMem /* First element */ + ExprList *pEList, /* Expression for each element */ + int regElem /* First element */ ){ - Vdbe *v; - int r1; + int iRet = 0; + int nResultCol = pEList->nExpr; + Vdbe *v = pParse->pVdbe; - v = pParse->pVdbe; - r1 = sqlite3GetTempReg(pParse); - sqlite3VdbeAddOp4Int(v, OP_Found, iTab, addrRepeat, iMem, N); VdbeCoverage(v); - sqlite3VdbeAddOp3(v, OP_MakeRecord, iMem, N, r1); - sqlite3VdbeAddOp4Int(v, OP_IdxInsert, iTab, r1, iMem, N); - sqlite3VdbeChangeP5(v, OPFLAG_USESEEKRESULT); - sqlite3ReleaseTempReg(pParse, r1); + switch( eTnctType ){ + case WHERE_DISTINCT_ORDERED: { + int i; + int iJump; /* Jump destination */ + int regPrev; /* Previous row content */ + + /* Allocate space for the previous row */ + iRet = regPrev = pParse->nMem+1; + pParse->nMem += nResultCol; + + iJump = sqlite3VdbeCurrentAddr(v) + nResultCol; + for(i=0; i<nResultCol; i++){ + CollSeq *pColl = sqlite3ExprCollSeq(pParse, pEList->a[i].pExpr); + if( i<nResultCol-1 ){ + sqlite3VdbeAddOp3(v, OP_Ne, regElem+i, iJump, regPrev+i); + VdbeCoverage(v); + }else{ + sqlite3VdbeAddOp3(v, OP_Eq, regElem+i, addrRepeat, regPrev+i); + VdbeCoverage(v); + } + sqlite3VdbeChangeP4(v, -1, (const char *)pColl, P4_COLLSEQ); + sqlite3VdbeChangeP5(v, SQLITE_NULLEQ); + } + assert( sqlite3VdbeCurrentAddr(v)==iJump || pParse->db->mallocFailed ); + sqlite3VdbeAddOp3(v, OP_Copy, regElem, regPrev, nResultCol-1); + break; + } + + case WHERE_DISTINCT_UNIQUE: { + /* nothing to do */ + break; + } + + default: { + int r1 = sqlite3GetTempReg(pParse); + sqlite3VdbeAddOp4Int(v, OP_Found, iTab, addrRepeat, regElem, nResultCol); + VdbeCoverage(v); + sqlite3VdbeAddOp3(v, OP_MakeRecord, regElem, nResultCol, r1); + sqlite3VdbeAddOp4Int(v, OP_IdxInsert, iTab, r1, regElem, nResultCol); + sqlite3VdbeChangeP5(v, OPFLAG_USESEEKRESULT); + sqlite3ReleaseTempReg(pParse, r1); + iRet = iTab; + break; + } + } + + return iRet; +} + +/* +** This routine runs after codeDistinct(). It makes necessary +** adjustments to the OP_OpenEphemeral opcode that the codeDistinct() +** routine made use of. This processing must be done separately since +** sometimes codeDistinct is called before the OP_OpenEphemeral is actually +** laid down. +** +** WHERE_DISTINCT_NOOP: +** WHERE_DISTINCT_UNORDERED: +** +** No adjustments necessary. This function is a no-op. +** +** WHERE_DISTINCT_UNIQUE: +** +** The ephemeral table is not needed. So change the +** OP_OpenEphemeral opcode into an OP_Noop. +** +** WHERE_DISTINCT_ORDERED: +** +** The ephemeral table is not needed. But we do need register +** iVal to be initialized to NULL. So change the OP_OpenEphemeral +** into an OP_Null on the iVal register. +*/ +static void fixDistinctOpenEph( + Parse *pParse, /* Parsing and code generating context */ + int eTnctType, /* WHERE_DISTINCT_* value */ + int iVal, /* Value returned by codeDistinct() */ + int iOpenEphAddr /* Address of OP_OpenEphemeral instruction for iTab */ +){ + if( pParse->nErr==0 + && (eTnctType==WHERE_DISTINCT_UNIQUE || eTnctType==WHERE_DISTINCT_ORDERED) + ){ + Vdbe *v = pParse->pVdbe; + sqlite3VdbeChangeToNoop(v, iOpenEphAddr); + if( sqlite3VdbeGetOp(v, iOpenEphAddr+1)->opcode==OP_Explain ){ + sqlite3VdbeChangeToNoop(v, iOpenEphAddr+1); + } + if( eTnctType==WHERE_DISTINCT_ORDERED ){ + /* Change the OP_OpenEphemeral to an OP_Null that sets the MEM_Cleared + ** bit on the first register of the previous value. This will cause the + ** OP_Ne added in codeDistinct() to always fail on the first iteration of + ** the loop even if the first row is all NULLs. */ + VdbeOp *pOp = sqlite3VdbeGetOp(v, iOpenEphAddr); + pOp->opcode = OP_Null; + pOp->p1 = 1; + pOp->p2 = iVal; + } + } } #ifdef SQLITE_ENABLE_SORTER_REFERENCES /* ** This function is called as part of inner-loop generation for a SELECT -** statement with an ORDER BY that is not optimized by an index. It -** determines the expressions, if any, that the sorter-reference +** statement with an ORDER BY that is not optimized by an index. It +** determines the expressions, if any, that the sorter-reference ** optimization should be used for. The sorter-reference optimization ** is used for SELECT queries like: ** @@ -787,11 +1017,11 @@ static void codeDistinct( ** storing values read from that column in the sorter records, the PK of ** the row from table t1 is stored instead. Then, as records are extracted from ** the sorter to return to the user, the required value of bigblob is -** retrieved directly from table t1. If the values are very large, this +** retrieved directly from table t1. If the values are very large, this ** can be more efficient than storing them directly in the sorter records. ** -** The ExprList_item.bSorterRef flag is set for each expression in pEList -** for which the sorter-reference optimization should be enabled. +** The ExprList_item.fg.bSorterRef flag is set for each expression in pEList +** for which the sorter-reference optimization should be enabled. ** Additionally, the pSort->aDefer[] array is populated with entries ** for all cursors required to evaluate all selected expressions. Finally. ** output variable (*ppExtra) is set to an expression list containing @@ -811,9 +1041,13 @@ static void selectExprDefer( struct ExprList_item *pItem = &pEList->a[i]; if( pItem->u.x.iOrderByCol==0 ){ Expr *pExpr = pItem->pExpr; - Table *pTab = pExpr->y.pTab; - if( pExpr->op==TK_COLUMN && pExpr->iColumn>=0 && pTab && !IsVirtual(pTab) - && (pTab->aCol[pExpr->iColumn].colFlags & COLFLAG_SORTERREF) + Table *pTab; + if( pExpr->op==TK_COLUMN + && pExpr->iColumn>=0 + && ALWAYS( ExprUseYTab(pExpr) ) + && (pTab = pExpr->y.pTab)!=0 + && IsOrdinaryTable(pTab) + && (pTab->aCol[pExpr->iColumn].colFlags & COLFLAG_SORTERREF)!=0 ){ int j; for(j=0; j<nDefer; j++){ @@ -834,6 +1068,7 @@ static void selectExprDefer( Expr *pNew = sqlite3PExpr(pParse, TK_COLUMN, 0, 0); if( pNew ){ pNew->iTable = pExpr->iTable; + assert( ExprUseYTab(pNew) ); pNew->y.pTab = pExpr->y.pTab; pNew->iColumn = pPk ? pPk->aiColumn[k] : -1; pExtra = sqlite3ExprListAppend(pParse, pExtra, pNew); @@ -845,7 +1080,7 @@ static void selectExprDefer( nDefer++; } } - pItem->bSorterRef = 1; + pItem->fg.bSorterRef = 1; } } } @@ -860,7 +1095,7 @@ static void selectExprDefer( ** ** If srcTab is negative, then the p->pEList expressions ** are evaluated in order to get the data for this row. If srcTab is -** zero or more, then data is pulled from srcTab and p->pEList is used only +** zero or more, then data is pulled from srcTab and p->pEList is used only ** to get the number of columns and the collation sequence for each column. */ static void selectInnerLoop( @@ -942,8 +1177,8 @@ static void selectInnerLoop( } if( pSort && hasDistinct==0 && eDest!=SRT_EphemTab && eDest!=SRT_Table ){ /* For each expression in p->pEList that is a copy of an expression in - ** the ORDER BY clause (pSort->pOrderBy), set the associated - ** iOrderByCol value to one more than the index of the ORDER BY + ** the ORDER BY clause (pSort->pOrderBy), set the associated + ** iOrderByCol value to one more than the index of the ORDER BY ** expression within the sort-key that pushOntoSorter() will generate. ** This allows the p->pEList field to be omitted from the sorted record, ** saving space and CPU cycles. */ @@ -959,7 +1194,7 @@ static void selectInnerLoop( selectExprDefer(pParse, pSort, p->pEList, &pExtra); if( pExtra && pParse->db->mallocFailed==0 ){ /* If there are any extra PK columns to add to the sorter records, - ** allocate extra memory cells and adjust the OpenEphemeral + ** allocate extra memory cells and adjust the OpenEphemeral ** instruction to account for the larger records. This is only ** required if there are one or more WITHOUT ROWID tables with ** composite primary keys in the SortCtx.aDefer[] array. */ @@ -976,7 +1211,7 @@ static void selectInnerLoop( for(i=0; i<pEList->nExpr; i++){ if( pEList->a[i].u.x.iOrderByCol>0 #ifdef SQLITE_ENABLE_SORTER_REFERENCES - || pEList->a[i].bSorterRef + || pEList->a[i].fg.bSorterRef #endif ){ nResultCol--; @@ -989,8 +1224,9 @@ static void selectInnerLoop( testcase( eDest==SRT_Mem ); testcase( eDest==SRT_Coroutine ); testcase( eDest==SRT_Output ); - assert( eDest==SRT_Set || eDest==SRT_Mem - || eDest==SRT_Coroutine || eDest==SRT_Output ); + assert( eDest==SRT_Set || eDest==SRT_Mem + || eDest==SRT_Coroutine || eDest==SRT_Output + || eDest==SRT_Upfrom ); } sRowLoadInfo.regResult = regResult; sRowLoadInfo.ecelFlags = ecelFlags; @@ -1000,7 +1236,7 @@ static void selectInnerLoop( if( pExtra ) nResultCol += pExtra->nExpr; #endif if( p->iLimit - && (ecelFlags & SQLITE_ECEL_OMITREF)!=0 + && (ecelFlags & SQLITE_ECEL_OMITREF)!=0 && nPrefixReg>0 ){ assert( pSort!=0 ); @@ -1017,59 +1253,11 @@ static void selectInnerLoop( ** part of the result. */ if( hasDistinct ){ - switch( pDistinct->eTnctType ){ - case WHERE_DISTINCT_ORDERED: { - VdbeOp *pOp; /* No longer required OpenEphemeral instr. */ - int iJump; /* Jump destination */ - int regPrev; /* Previous row content */ - - /* Allocate space for the previous row */ - regPrev = pParse->nMem+1; - pParse->nMem += nResultCol; - - /* Change the OP_OpenEphemeral coded earlier to an OP_Null - ** sets the MEM_Cleared bit on the first register of the - ** previous value. This will cause the OP_Ne below to always - ** fail on the first iteration of the loop even if the first - ** row is all NULLs. - */ - sqlite3VdbeChangeToNoop(v, pDistinct->addrTnct); - pOp = sqlite3VdbeGetOp(v, pDistinct->addrTnct); - pOp->opcode = OP_Null; - pOp->p1 = 1; - pOp->p2 = regPrev; - pOp = 0; /* Ensure pOp is not used after sqlite3VdbeAddOp() */ - - iJump = sqlite3VdbeCurrentAddr(v) + nResultCol; - for(i=0; i<nResultCol; i++){ - CollSeq *pColl = sqlite3ExprCollSeq(pParse, p->pEList->a[i].pExpr); - if( i<nResultCol-1 ){ - sqlite3VdbeAddOp3(v, OP_Ne, regResult+i, iJump, regPrev+i); - VdbeCoverage(v); - }else{ - sqlite3VdbeAddOp3(v, OP_Eq, regResult+i, iContinue, regPrev+i); - VdbeCoverage(v); - } - sqlite3VdbeChangeP4(v, -1, (const char *)pColl, P4_COLLSEQ); - sqlite3VdbeChangeP5(v, SQLITE_NULLEQ); - } - assert( sqlite3VdbeCurrentAddr(v)==iJump || pParse->db->mallocFailed ); - sqlite3VdbeAddOp3(v, OP_Copy, regResult, regPrev, nResultCol-1); - break; - } - - case WHERE_DISTINCT_UNIQUE: { - sqlite3VdbeChangeToNoop(v, pDistinct->addrTnct); - break; - } - - default: { - assert( pDistinct->eTnctType==WHERE_DISTINCT_UNORDERED ); - codeDistinct(pParse, pDistinct->tabTnct, iContinue, nResultCol, - regResult); - break; - } - } + int eType = pDistinct->eTnctType; + int iTab = pDistinct->tabTnct; + assert( nResultCol==p->pEList->nExpr ); + iTab = codeDistinct(pParse, eType, iTab, iContinue, p->pEList, regResult); + fixDistinctOpenEph(pParse, eType, iTab, pDistinct->addrTnct); if( pSort==0 ){ codeOffset(v, p->iOffset, iContinue); } @@ -1111,6 +1299,16 @@ static void selectInnerLoop( testcase( eDest==SRT_Fifo ); testcase( eDest==SRT_DistFifo ); sqlite3VdbeAddOp3(v, OP_MakeRecord, regResult, nResultCol, r1+nPrefixReg); +#if !defined(SQLITE_ENABLE_NULL_TRIM) && defined(SQLITE_DEBUG) + /* A destination of SRT_Table and a non-zero iSDParm2 parameter means + ** that this is an "UPDATE ... FROM" on a virtual table or view. In this + ** case set the p5 parameter of the OP_MakeRecord to OPFLAG_NOCHNG_MAGIC. + ** This does not affect operation in any way - it just allows MakeRecord + ** to process OPFLAG_NOCHANGE values without an assert() failing. */ + if( eDest==SRT_Table && pDest->iSDParm2 ){ + sqlite3VdbeChangeP5(v, OPFLAG_NOCHNG_MAGIC); + } +#endif #ifndef SQLITE_OMIT_CTE if( eDest==SRT_DistFifo ){ /* If the destination is DistFifo, then cursor (iParm+1) is open @@ -1139,6 +1337,30 @@ static void selectInnerLoop( break; } + case SRT_Upfrom: { + if( pSort ){ + pushOntoSorter( + pParse, pSort, p, regResult, regOrig, nResultCol, nPrefixReg); + }else{ + int i2 = pDest->iSDParm2; + int r1 = sqlite3GetTempReg(pParse); + + /* If the UPDATE FROM join is an aggregate that matches no rows, it + ** might still be trying to return one row, because that is what + ** aggregates do. Don't record that empty row in the output table. */ + sqlite3VdbeAddOp2(v, OP_IsNull, regResult, iBreak); VdbeCoverage(v); + + sqlite3VdbeAddOp3(v, OP_MakeRecord, + regResult+(i2<0), nResultCol-(i2<0), r1); + if( i2<0 ){ + sqlite3VdbeAddOp3(v, OP_Insert, iParm, r1, regResult); + }else{ + sqlite3VdbeAddOp4Int(v, OP_IdxInsert, iParm, r1, regResult, i2); + } + } + break; + } + #ifndef SQLITE_OMIT_SUBQUERY /* If we are creating a set for an "expr IN (SELECT ...)" construct, ** then there should be a single item on the stack. Write this @@ -1155,7 +1377,7 @@ static void selectInnerLoop( }else{ int r1 = sqlite3GetTempReg(pParse); assert( sqlite3Strlen30(pDest->zAffSdst)==nResultCol ); - sqlite3VdbeAddOp4(v, OP_MakeRecord, regResult, nResultCol, + sqlite3VdbeAddOp4(v, OP_MakeRecord, regResult, nResultCol, r1, pDest->zAffSdst, nResultCol); sqlite3VdbeAddOp4Int(v, OP_IdxInsert, iParm, r1, regResult, nResultCol); sqlite3ReleaseTempReg(pParse, r1); @@ -1163,6 +1385,7 @@ static void selectInnerLoop( break; } + /* If any row exist in the result set, record that fact and abort. */ case SRT_Exists: { @@ -1172,7 +1395,7 @@ static void selectInnerLoop( } /* If this is a scalar select that is part of an expression, then - ** store the results in the appropriate memory cell or array of + ** store the results in the appropriate memory cell or array of ** memory cells and break out of the scan loop. */ case SRT_Mem: { @@ -1227,7 +1450,7 @@ static void selectInnerLoop( /* If the destination is DistQueue, then cursor (iParm+1) is open ** on a second ephemeral index that holds all values every previously ** added to the queue. */ - addrTest = sqlite3VdbeAddOp4Int(v, OP_Found, iParm+1, 0, + addrTest = sqlite3VdbeAddOp4Int(v, OP_Found, iParm+1, 0, regResult, nResultCol); VdbeCoverage(v); } @@ -1291,7 +1514,7 @@ KeyInfo *sqlite3KeyInfoAlloc(sqlite3 *db, int N, int X){ p->nRef = 1; memset(&p[1], 0, nExtra); }else{ - sqlite3OomFault(db); + return (KeyInfo*)sqlite3OomFault(db); } return p; } @@ -1301,9 +1524,10 @@ KeyInfo *sqlite3KeyInfoAlloc(sqlite3 *db, int N, int X){ */ void sqlite3KeyInfoUnref(KeyInfo *p){ if( p ){ + assert( p->db!=0 ); assert( p->nRef>0 ); p->nRef--; - if( p->nRef==0 ) sqlite3DbFreeNN(p->db, p); + if( p->nRef==0 ) sqlite3DbNNFreeNN(p->db, p); } } @@ -1360,7 +1584,7 @@ KeyInfo *sqlite3KeyInfoFromExprList( assert( sqlite3KeyInfoIsWriteable(pInfo) ); for(i=iStart, pItem=pList->a+iStart; i<nExpr; i++, pItem++){ pInfo->aColl[i-iStart] = sqlite3ExprNNCollSeq(pParse, pItem->pExpr); - pInfo->aSortFlags[i-iStart] = pItem->sortFlags; + pInfo->aSortFlags[i-iStart] = pItem->fg.sortFlags; } } return pInfo; @@ -1369,7 +1593,7 @@ KeyInfo *sqlite3KeyInfoFromExprList( /* ** Name of the connection operator, used for error messages. */ -static const char *selectOpName(int id){ +const char *sqlite3SelectOpName(int id){ char *z; switch( id ){ case TK_ALL: z = "UNION ALL"; break; @@ -1442,6 +1666,16 @@ static void generateSortTail( int bSeq; /* True if sorter record includes seq. no. */ int nRefKey = 0; struct ExprList_item *aOutEx = p->pEList->a; +#ifdef SQLITE_ENABLE_STMT_SCANSTATUS + int addrExplain; /* Address of OP_Explain instruction */ +#endif + + ExplainQueryPlan2(addrExplain, (pParse, 0, + "USE TEMP B-TREE FOR %sORDER BY", pSort->nOBSat>0?"RIGHT PART OF ":"") + ); + sqlite3VdbeScanStatusRange(v, addrExplain,pSort->addrPush,pSort->addrPushEnd); + sqlite3VdbeScanStatusCounters(v, addrExplain, addrExplain, pSort->addrPush); + assert( addrBreak<0 ); if( pSort->labelBkOut ){ @@ -1462,6 +1696,9 @@ static void generateSortTail( iTab = pSort->iECursor; if( eDest==SRT_Output || eDest==SRT_Coroutine || eDest==SRT_Mem ){ + if( eDest==SRT_Mem && p->iOffset ){ + sqlite3VdbeAddOp2(v, OP_Null, 0, pDest->iSdst); + } regRowid = 0; regRow = pDest->iSdst; }else{ @@ -1480,12 +1717,12 @@ static void generateSortTail( if( pSort->labelBkOut ){ addrOnce = sqlite3VdbeAddOp0(v, OP_Once); VdbeCoverage(v); } - sqlite3VdbeAddOp3(v, OP_OpenPseudo, iSortTab, regSortOut, + sqlite3VdbeAddOp3(v, OP_OpenPseudo, iSortTab, regSortOut, nKey+1+nColumn+nRefKey); if( addrOnce ) sqlite3VdbeJumpHere(v, addrOnce); addr = 1 + sqlite3VdbeAddOp2(v, OP_SorterSort, iTab, addrBreak); VdbeCoverage(v); - codeOffset(v, p->iOffset, addrContinue); + assert( p->iLimit==0 && p->iOffset==0 ); sqlite3VdbeAddOp3(v, OP_SorterData, iTab, regSortOut, iSortTab); bSeq = 0; }else{ @@ -1493,10 +1730,13 @@ static void generateSortTail( codeOffset(v, p->iOffset, addrContinue); iSortTab = iTab; bSeq = 1; + if( p->iOffset>0 ){ + sqlite3VdbeAddOp2(v, OP_AddImm, p->iLimit, -1); + } } for(i=0, iCol=nKey+bSeq-1; i<nColumn; i++){ #ifdef SQLITE_ENABLE_SORTER_REFERENCES - if( aOutEx[i].bSorterRef ) continue; + if( aOutEx[i].fg.bSorterRef ) continue; #endif if( aOutEx[i].u.x.iOrderByCol==0 ) iCol++; } @@ -1513,7 +1753,7 @@ static void generateSortTail( sqlite3VdbeAddOp1(v, OP_NullRow, iCsr); if( HasRowid(pTab) ){ sqlite3VdbeAddOp3(v, OP_Column, iSortTab, iKey++, regKey); - sqlite3VdbeAddOp3(v, OP_SeekRowid, iCsr, + sqlite3VdbeAddOp3(v, OP_SeekRowid, iCsr, sqlite3VdbeCurrentAddr(v)+1, regKey); }else{ int k; @@ -1533,7 +1773,7 @@ static void generateSortTail( #endif for(i=nColumn-1; i>=0; i--){ #ifdef SQLITE_ENABLE_SORTER_REFERENCES - if( aOutEx[i].bSorterRef ){ + if( aOutEx[i].fg.bSorterRef ){ sqlite3ExprCode(pParse, aOutEx[i].pExpr, regRow+i); }else #endif @@ -1548,6 +1788,7 @@ static void generateSortTail( VdbeComment((v, "%s", aOutEx[i].zEName)); } } + sqlite3VdbeScanStatusRange(v, addrExplain, addrExplain, -1); switch( eDest ){ case SRT_Table: case SRT_EphemTab: { @@ -1570,8 +1811,19 @@ static void generateSortTail( break; } #endif + case SRT_Upfrom: { + int i2 = pDest->iSDParm2; + int r1 = sqlite3GetTempReg(pParse); + sqlite3VdbeAddOp3(v, OP_MakeRecord,regRow+(i2<0),nColumn-(i2<0),r1); + if( i2<0 ){ + sqlite3VdbeAddOp3(v, OP_Insert, iParm, r1, regRow); + }else{ + sqlite3VdbeAddOp4Int(v, OP_IdxInsert, iParm, r1, regRow, i2); + } + break; + } default: { - assert( eDest==SRT_Output || eDest==SRT_Coroutine ); + assert( eDest==SRT_Output || eDest==SRT_Coroutine ); testcase( eDest==SRT_Output ); testcase( eDest==SRT_Coroutine ); if( eDest==SRT_Output ){ @@ -1598,6 +1850,7 @@ static void generateSortTail( }else{ sqlite3VdbeAddOp2(v, OP_Next, iTab, addr); VdbeCoverage(v); } + sqlite3VdbeScanStatusRange(v, addrExplain, sqlite3VdbeCurrentAddr(v)-1, -1); if( pSort->regReturn ) sqlite3VdbeAddOp1(v, OP_Return, pSort->regReturn); sqlite3VdbeResolveLabel(v, addrBreak); } @@ -1606,21 +1859,18 @@ static void generateSortTail( ** Return a pointer to a string containing the 'declaration type' of the ** expression pExpr. The string may be treated as static by the caller. ** -** Also try to estimate the size of the returned value and return that -** result in *pEstWidth. -** ** The declaration type is the exact datatype definition extracted from the ** original CREATE TABLE statement if the expression is a column. The ** declaration type for a ROWID field is INTEGER. Exactly when an expression ** is considered a column can be complex in the presence of subqueries. The -** result-set expression in all of the following SELECT statements is +** result-set expression in all of the following SELECT statements is ** considered a column by this function. ** ** SELECT col FROM tbl; ** SELECT (SELECT col FROM tbl; ** SELECT (SELECT col FROM tbl); ** SELECT abc FROM (SELECT col AS abc FROM tbl); -** +** ** The declaration type for any expression other than a column is NULL. ** ** This routine has either 3 or 6 parameters depending on whether or not @@ -1632,7 +1882,7 @@ static void generateSortTail( # define columnType(A,B,C,D,E) columnTypeImpl(A,B) #endif static const char *columnTypeImpl( - NameContext *pNC, + NameContext *pNC, #ifndef SQLITE_ENABLE_COLUMN_METADATA Expr *pExpr #else @@ -1675,33 +1925,39 @@ static const char *columnTypeImpl( if( pTab==0 ){ /* 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 + ** trigger code is generated and so this condition is no longer ** possible. However, it can still be true for statements like ** the following: ** ** CREATE TABLE t1(col INTEGER); ** SELECT (SELECT t1.col) FROM FROM t1; ** - ** when columnType() is called on the expression "t1.col" in the + ** 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 + ** 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 && pExpr->y.pTab==pTab ); + assert( pTab && ExprUseYTab(pExpr) && pExpr->y.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( iCol<pS->pEList->nExpr +#ifdef SQLITE_ALLOW_ROWID_IN_VIEW + && iCol>=0 +#else + && ALWAYS(iCol>=0) +#endif + ){ /* If iCol is less than zero, then the expression requests the - ** rowid of the sub-select or view. This expression is legal (see + ** rowid of the sub-select or view. This expression is legal (see ** test case misc2.2.2) - it always evaluates to NULL. */ NameContext sNC; @@ -1709,7 +1965,7 @@ static const char *columnTypeImpl( sNC.pSrcList = pS->pSrc; sNC.pNext = pNC; sNC.pParse = pNC->pParse; - zType = columnType(&sNC, p,&zOrigDb,&zOrigTab,&zOrigCol); + zType = columnType(&sNC, p,&zOrigDb,&zOrigTab,&zOrigCol); } }else{ /* A real table or a CTE table */ @@ -1721,7 +1977,7 @@ static const char *columnTypeImpl( zType = "INTEGER"; zOrigCol = "rowid"; }else{ - zOrigCol = pTab->aCol[iCol].zName; + zOrigCol = pTab->aCol[iCol].zCnName; zType = sqlite3ColumnType(&pTab->aCol[iCol],0); } zOrigTab = pTab->zName; @@ -1747,19 +2003,21 @@ static const char *columnTypeImpl( ** statement. */ NameContext sNC; - Select *pS = pExpr->x.pSelect; - Expr *p = pS->pEList->a[0].pExpr; - assert( ExprHasProperty(pExpr, EP_xIsSelect) ); + Select *pS; + Expr *p; + assert( ExprUseXSelect(pExpr) ); + pS = pExpr->x.pSelect; + p = pS->pEList->a[0].pExpr; sNC.pSrcList = pS->pSrc; sNC.pNext = pNC; sNC.pParse = pNC->pParse; - zType = columnType(&sNC, p, &zOrigDb, &zOrigTab, &zOrigCol); + zType = columnType(&sNC, p, &zOrigDb, &zOrigTab, &zOrigCol); break; } #endif } -#ifdef SQLITE_ENABLE_COLUMN_METADATA +#ifdef SQLITE_ENABLE_COLUMN_METADATA if( pzOrigDb ){ assert( pzOrigTab && pzOrigCol ); *pzOrigDb = zOrigDb; @@ -1795,7 +2053,7 @@ static void generateColumnTypes( const char *zOrigCol = 0; zType = columnType(&sNC, p, &zOrigDb, &zOrigTab, &zOrigCol); - /* The vdbe must make its own copy of the column-type and other + /* The vdbe must make its own copy of the column-type and other ** column specific strings, in case the schema is reset before this ** virtual machine is deleted. */ @@ -1841,7 +2099,7 @@ static void generateColumnTypes( ** then the result column name with the table name ** prefix, ex: TABLE.COLUMN. Otherwise use zSpan. */ -static void generateColumnNames( +void sqlite3GenerateColumnNames( Parse *pParse, /* Parser context */ Select *pSelect /* Generate column names for this SELECT statement */ ){ @@ -1854,17 +2112,10 @@ static void generateColumnNames( int fullName; /* TABLE.COLUMN if no AS clause and is a direct table ref */ int srcName; /* COLUMN or TABLE.COLUMN if no AS clause and is direct */ -#ifndef SQLITE_OMIT_EXPLAIN - /* If this is an EXPLAIN, skip this step */ - if( pParse->explain ){ - return; - } -#endif - if( pParse->colNamesSet ) return; /* Column names are determined by the left-most term of a compound select */ while( pSelect->pPrior ) pSelect = pSelect->pPrior; - SELECTTRACE(1,pParse,pSelect,("generating column names\n")); + TREETRACE(0x80,pParse,pSelect,("generating column names\n")); pTabList = pSelect->pSrc; pEList = pSelect->pEList; assert( v!=0 ); @@ -1878,8 +2129,9 @@ static void generateColumnNames( assert( p!=0 ); assert( p->op!=TK_AGG_COLUMN ); /* Agg processing has not run yet */ - assert( p->op!=TK_COLUMN || p->y.pTab!=0 ); /* Covering idx not yet coded */ - if( pEList->a[i].zEName && pEList->a[i].eEName==ENAME_NAME ){ + assert( p->op!=TK_COLUMN + || (ExprUseYTab(p) && p->y.pTab!=0) ); /* Covering idx not yet coded */ + if( pEList->a[i].zEName && pEList->a[i].fg.eEName==ENAME_NAME ){ /* An AS clause always takes first priority */ char *zName = pEList->a[i].zEName; sqlite3VdbeSetColName(v, i, COLNAME_NAME, zName, SQLITE_TRANSIENT); @@ -1893,7 +2145,7 @@ static void generateColumnNames( if( iCol<0 ){ zCol = "rowid"; }else{ - zCol = pTab->aCol[iCol].zName; + zCol = pTab->aCol[iCol].zCnName; } if( fullName ){ char *zName = 0; @@ -1931,7 +2183,7 @@ static void generateColumnNames( ** and will break if those assumptions changes. Hence, use extreme caution ** when modifying this routine to avoid breaking legacy. ** -** See Also: generateColumnNames() +** See Also: sqlite3GenerateColumnNames() */ int sqlite3ColumnsFromExprList( Parse *pParse, /* Parsing context */ @@ -1947,13 +2199,14 @@ int sqlite3ColumnsFromExprList( char *zName; /* Column name */ int nName; /* Size of name in zName[] */ Hash ht; /* Hash table of column names */ + Table *pTab; sqlite3HashInit(&ht); if( pEList ){ nCol = pEList->nExpr; aCol = sqlite3DbMallocZero(db, sizeof(aCol[0])*nCol); testcase( aCol==0 ); - if( nCol>32767 ) nCol = 32767; + if( NEVER(nCol>32767) ) nCol = 32767; }else{ nCol = 0; aCol = 0; @@ -1962,30 +2215,34 @@ int sqlite3ColumnsFromExprList( *pnCol = nCol; *paCol = aCol; - for(i=0, pCol=aCol; i<nCol && !db->mallocFailed; i++, pCol++){ + for(i=0, pCol=aCol; i<nCol && !pParse->nErr; i++, pCol++){ + struct ExprList_item *pX = &pEList->a[i]; + struct ExprList_item *pCollide; /* Get an appropriate name for the column */ - if( (zName = pEList->a[i].zEName)!=0 && pEList->a[i].eEName==ENAME_NAME ){ + if( (zName = pX->zEName)!=0 && pX->fg.eEName==ENAME_NAME ){ /* If the column contains an "AS <name>" phrase, use <name> as the name */ }else{ - Expr *pColExpr = sqlite3ExprSkipCollateAndLikely(pEList->a[i].pExpr); - while( pColExpr->op==TK_DOT ){ + Expr *pColExpr = sqlite3ExprSkipCollateAndLikely(pX->pExpr); + while( ALWAYS(pColExpr!=0) && pColExpr->op==TK_DOT ){ pColExpr = pColExpr->pRight; assert( pColExpr!=0 ); } - if( pColExpr->op==TK_COLUMN ){ + if( pColExpr->op==TK_COLUMN + && ALWAYS( ExprUseYTab(pColExpr) ) + && ALWAYS( pColExpr->y.pTab!=0 ) + ){ /* For columns use the column name name */ int iCol = pColExpr->iColumn; - Table *pTab = pColExpr->y.pTab; - assert( pTab!=0 ); + pTab = pColExpr->y.pTab; if( iCol<0 ) iCol = pTab->iPKey; - zName = iCol>=0 ? pTab->aCol[iCol].zName : "rowid"; + zName = iCol>=0 ? pTab->aCol[iCol].zCnName : "rowid"; }else if( pColExpr->op==TK_ID ){ assert( !ExprHasProperty(pColExpr, EP_IntValue) ); zName = pColExpr->u.zToken; }else{ /* Use the original text of the column expression as its name */ - zName = pEList->a[i].zEName; + assert( zName==pX->zEName ); /* pointer comparison intended */ } } if( zName && !sqlite3IsTrueOrFalse(zName) ){ @@ -1998,87 +2255,134 @@ int sqlite3ColumnsFromExprList( ** append an integer to the name so that it becomes unique. */ cnt = 0; - while( zName && sqlite3HashFind(&ht, zName)!=0 ){ + while( zName && (pCollide = sqlite3HashFind(&ht, zName))!=0 ){ + if( pCollide->fg.bUsingTerm ){ + pCol->colFlags |= COLFLAG_NOEXPAND; + } nName = sqlite3Strlen30(zName); if( nName>0 ){ for(j=nName-1; j>0 && sqlite3Isdigit(zName[j]); j--){} if( zName[j]==':' ) nName = j; } zName = sqlite3MPrintf(db, "%.*z:%u", nName, zName, ++cnt); - if( cnt>3 ) sqlite3_randomness(sizeof(cnt), &cnt); + sqlite3ProgressCheck(pParse); + if( cnt>3 ){ + sqlite3_randomness(sizeof(cnt), &cnt); + } } - pCol->zName = zName; + pCol->zCnName = zName; pCol->hName = sqlite3StrIHash(zName); + if( pX->fg.bNoExpand ){ + pCol->colFlags |= COLFLAG_NOEXPAND; + } sqlite3ColumnPropertiesFromName(0, pCol); - if( zName && sqlite3HashInsert(&ht, zName, pCol)==pCol ){ + if( zName && sqlite3HashInsert(&ht, zName, pX)==pX ){ sqlite3OomFault(db); } } sqlite3HashClear(&ht); - if( db->mallocFailed ){ + if( pParse->nErr ){ for(j=0; j<i; j++){ - sqlite3DbFree(db, aCol[j].zName); + sqlite3DbFree(db, aCol[j].zCnName); } sqlite3DbFree(db, aCol); *paCol = 0; *pnCol = 0; - return SQLITE_NOMEM_BKPT; + return pParse->rc; } return SQLITE_OK; } /* -** 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. -** -** This routine requires that all identifiers in the SELECT -** statement be resolved. +** pTab is a transient Table object that represents a subquery of some +** kind (maybe a parenthesized subquery in the FROM clause of a larger +** query, or a VIEW, or a CTE). This routine computes type information +** for that Table object based on the Select object that implements the +** subquery. For the purposes of this routine, "type information" means: +** +** * The datatype name, as it might appear in a CREATE TABLE statement +** * Which collating sequence to use for the column +** * The affinity of the column */ -void sqlite3SelectAddColumnTypeAndCollation( - Parse *pParse, /* Parsing contexts */ - Table *pTab, /* Add column type information to this table */ - Select *pSelect, /* SELECT used to determine types and collations */ - char aff /* Default affinity for columns */ +void sqlite3SubqueryColumnTypes( + Parse *pParse, /* Parsing contexts */ + Table *pTab, /* Add column type information to this table */ + Select *pSelect, /* SELECT used to determine types and collations */ + char aff /* Default affinity. */ ){ sqlite3 *db = pParse->db; - NameContext sNC; Column *pCol; CollSeq *pColl; - int i; + int i,j; Expr *p; struct ExprList_item *a; + NameContext sNC; assert( pSelect!=0 ); assert( (pSelect->selFlags & SF_Resolved)!=0 ); - assert( pTab->nCol==pSelect->pEList->nExpr || db->mallocFailed ); - if( db->mallocFailed ) return; + assert( pTab->nCol==pSelect->pEList->nExpr || pParse->nErr>0 ); + assert( aff==SQLITE_AFF_NONE || aff==SQLITE_AFF_BLOB ); + if( db->mallocFailed || IN_RENAME_OBJECT ) return; + while( pSelect->pPrior ) pSelect = pSelect->pPrior; + a = pSelect->pEList->a; memset(&sNC, 0, sizeof(sNC)); sNC.pSrcList = pSelect->pSrc; - a = pSelect->pEList->a; for(i=0, pCol=pTab->aCol; i<pTab->nCol; i++, pCol++){ const char *zType; - int n, m; + i64 n; + pTab->tabFlags |= (pCol->colFlags & COLFLAG_NOINSERT); p = a[i].pExpr; - zType = columnType(&sNC, p, 0, 0, 0); /* pCol->szEst = ... // Column size est for SELECT tables never used */ pCol->affinity = sqlite3ExprAffinity(p); + if( pCol->affinity<=SQLITE_AFF_NONE ){ + pCol->affinity = aff; + } + if( pCol->affinity>=SQLITE_AFF_TEXT && pSelect->pNext ){ + int m = 0; + Select *pS2; + for(m=0, pS2=pSelect->pNext; pS2; pS2=pS2->pNext){ + m |= sqlite3ExprDataType(pS2->pEList->a[i].pExpr); + } + if( pCol->affinity==SQLITE_AFF_TEXT && (m&0x01)!=0 ){ + pCol->affinity = SQLITE_AFF_BLOB; + }else + if( pCol->affinity>=SQLITE_AFF_NUMERIC && (m&0x02)!=0 ){ + pCol->affinity = SQLITE_AFF_BLOB; + } + if( pCol->affinity>=SQLITE_AFF_NUMERIC && p->op==TK_CAST ){ + pCol->affinity = SQLITE_AFF_FLEXNUM; + } + } + zType = columnType(&sNC, p, 0, 0, 0); + if( zType==0 || pCol->affinity!=sqlite3AffinityType(zType, 0) ){ + if( pCol->affinity==SQLITE_AFF_NUMERIC + || pCol->affinity==SQLITE_AFF_FLEXNUM + ){ + zType = "NUM"; + }else{ + zType = 0; + for(j=1; j<SQLITE_N_STDTYPE; j++){ + if( sqlite3StdTypeAffinity[j]==pCol->affinity ){ + zType = sqlite3StdType[j]; + break; + } + } + } + } if( zType ){ - m = sqlite3Strlen30(zType); - n = sqlite3Strlen30(pCol->zName); - pCol->zName = sqlite3DbReallocOrFree(db, pCol->zName, n+m+2); - if( pCol->zName ){ - memcpy(&pCol->zName[n+1], zType, m+1); + i64 m = sqlite3Strlen30(zType); + n = sqlite3Strlen30(pCol->zCnName); + pCol->zCnName = sqlite3DbReallocOrFree(db, pCol->zCnName, n+m+2); + pCol->colFlags &= ~(COLFLAG_HASTYPE|COLFLAG_HASCOLL); + if( pCol->zCnName ){ + memcpy(&pCol->zCnName[n+1], zType, m+1); pCol->colFlags |= COLFLAG_HASTYPE; } } - if( pCol->affinity<=SQLITE_AFF_NONE ) pCol->affinity = aff; pColl = sqlite3ExprCollSeq(pParse, p); - if( pColl && pCol->zColl==0 ){ - pCol->zColl = sqlite3DbStrDup(db, pColl->zName); + if( pColl ){ + assert( pTab->pIndex==0 ); + sqlite3ColumnSetColl(db, pCol, pColl->zName); } } pTab->szTabRow = 1; /* Any non-zero value works */ @@ -2108,7 +2412,7 @@ Table *sqlite3ResultSetOfSelect(Parse *pParse, Select *pSelect, char aff){ pTab->zName = 0; pTab->nRowLogEst = 200; assert( 200==sqlite3LogEst(1048576) ); sqlite3ColumnsFromExprList(pParse, pSelect->pEList, &pTab->nCol, &pTab->aCol); - sqlite3SelectAddColumnTypeAndCollation(pParse, pTab, pSelect, aff); + sqlite3SubqueryColumnTypes(pParse, pTab, pSelect, aff); pTab->iPKey = -1; if( db->mallocFailed ){ sqlite3DeleteTable(db, pTab); @@ -2138,9 +2442,9 @@ Vdbe *sqlite3GetVdbe(Parse *pParse){ ** Compute the iLimit and iOffset fields of the SELECT based on the ** pLimit expressions. pLimit->pLeft and pLimit->pRight hold the expressions ** that appear in the original SQL statement after the LIMIT and OFFSET -** keywords. Or NULL if those keywords are omitted. iLimit and iOffset -** are the integer memory register numbers for counters used to compute -** the limit and offset. If there is no limit and/or offset, then +** keywords. Or NULL if those keywords are omitted. iLimit and iOffset +** are the integer memory register numbers for counters used to compute +** the limit and offset. If there is no limit and/or offset, then ** iLimit and iOffset are negative. ** ** This routine changes the values of iLimit and iOffset only if @@ -2166,7 +2470,7 @@ static void computeLimitRegisters(Parse *pParse, Select *p, int iBreak){ if( p->iLimit ) return; - /* + /* ** "LIMIT -1" always shows all rows. There is some ** controversy about what the correct behavior should be. ** The current implementation interprets "LIMIT 0" to mean @@ -2242,7 +2546,7 @@ static CollSeq *multiSelectCollSeq(Parse *pParse, Select *p, int iCol){ */ static KeyInfo *multiSelectOrderByKeyInfo(Parse *pParse, Select *p, int nExtra){ ExprList *pOrderBy = p->pOrderBy; - int nOrderBy = p->pOrderBy->nExpr; + int nOrderBy = ALWAYS(pOrderBy!=0) ? pOrderBy->nExpr : 0; sqlite3 *db = pParse->db; KeyInfo *pRet = sqlite3KeyInfoAlloc(db, nOrderBy+nExtra, 1); if( pRet ){ @@ -2262,7 +2566,7 @@ static KeyInfo *multiSelectOrderByKeyInfo(Parse *pParse, Select *p, int nExtra){ } assert( sqlite3KeyInfoIsWriteable(pRet) ); pRet->aColl[i] = pColl; - pRet->aSortFlags[i] = pOrderBy->a[i].sortFlags; + pRet->aSortFlags[i] = pOrderBy->a[i].fg.sortFlags; } } @@ -2294,7 +2598,7 @@ static KeyInfo *multiSelectOrderByKeyInfo(Parse *pParse, Select *p, int nExtra){ ** inserted into the Queue table. The iDistinct table keeps a copy of all rows ** that have ever been inserted into Queue and causes duplicates to be ** discarded. If the operator is UNION ALL, then duplicates are allowed. -** +** ** If the query has an ORDER BY, then entries in the Queue table are kept in ** ORDER BY order and the first entry is extracted for each cycle. Without ** an ORDER BY, the Queue table is just a FIFO. @@ -2314,7 +2618,8 @@ static void generateWithRecursiveQuery( SrcList *pSrc = p->pSrc; /* The FROM clause of the recursive query */ int nCol = p->pEList->nExpr; /* Number of columns in the recursive table */ Vdbe *v = pParse->pVdbe; /* The prepared statement under construction */ - Select *pSetup = p->pPrior; /* The setup query */ + Select *pSetup; /* The setup query */ + Select *pFirstRec; /* Left-most recursive term */ int addrTop; /* Top of the loop */ int addrCont, addrBreak; /* CONTINUE and BREAK addresses */ int iCurrent = 0; /* The Current table */ @@ -2322,7 +2627,7 @@ static void generateWithRecursiveQuery( int iQueue; /* The Queue table */ int iDistinct = 0; /* To ensure unique results if UNION */ int eDest = SRT_Fifo; /* How to write to Queue */ - SelectDest destQueue; /* SelectDest targetting the Queue table */ + SelectDest destQueue; /* SelectDest targeting the Queue table */ int i; /* Loop counter */ int rc; /* Result code */ ExprList *pOrderBy; /* The ORDER BY clause */ @@ -2390,7 +2695,24 @@ static void generateWithRecursiveQuery( /* Detach the ORDER BY clause from the compound SELECT */ p->pOrderBy = 0; + /* Figure out how many elements of the compound SELECT are part of the + ** recursive query. Make sure no recursive elements use aggregate + ** functions. Mark the recursive elements as UNION ALL even if they + ** are really UNION because the distinctness will be enforced by the + ** iDistinct table. pFirstRec is left pointing to the left-most + ** recursive term of the CTE. + */ + for(pFirstRec=p; ALWAYS(pFirstRec!=0); pFirstRec=pFirstRec->pPrior){ + if( pFirstRec->selFlags & SF_Aggregate ){ + sqlite3ErrorMsg(pParse, "recursive aggregate queries not supported"); + goto end_of_recursive_query; + } + pFirstRec->op = TK_ALL; + if( (pFirstRec->pPrior->selFlags & SF_Recursive)==0 ) break; + } + /* Store the results of the setup-query in Queue. */ + pSetup = pFirstRec->pPrior; pSetup->pNext = 0; ExplainQueryPlan((pParse, 1, "SETUP")); rc = sqlite3Select(pParse, pSetup, &destQueue); @@ -2423,15 +2745,11 @@ static void generateWithRecursiveQuery( /* Execute the recursive SELECT taking the single row in Current as ** the value for the recursive-table. Store the results in the Queue. */ - if( p->selFlags & SF_Aggregate ){ - sqlite3ErrorMsg(pParse, "recursive aggregate queries not supported"); - }else{ - p->pPrior = 0; - ExplainQueryPlan((pParse, 1, "RECURSIVE STEP")); - sqlite3Select(pParse, p, &destQueue); - assert( p->pPrior==0 ); - p->pPrior = pSetup; - } + pFirstRec->pPrior = 0; + ExplainQueryPlan((pParse, 1, "RECURSIVE STEP")); + sqlite3Select(pParse, p, &destQueue); + assert( pFirstRec->pPrior==0 ); + pFirstRec->pPrior = pSetup; /* Keep running the loop until the Queue is empty */ sqlite3VdbeGoto(v, addrTop); @@ -2466,7 +2784,7 @@ static int multiSelectOrderBy( ** The "LIMIT of exactly 1" case of condition (1) comes about when a VALUES ** clause occurs within scalar expression (ex: "SELECT (VALUES(1),(2),(3))"). ** The sqlite3CodeSubselect will have added the LIMIT 1 clause in tht case. -** Since the limit is exactly 1, we only need to evalutes the left-most VALUES. +** Since the limit is exactly 1, we only need to evaluate the left-most VALUES. */ static int multiSelectValues( Parse *pParse, /* Parsing context */ @@ -2501,13 +2819,23 @@ static int multiSelectValues( } /* +** Return true if the SELECT statement which is known to be the recursive +** part of a recursive CTE still has its anchor terms attached. If the +** anchor terms have already been removed, then return false. +*/ +static int hasAnchor(Select *p){ + while( p && (p->selFlags & SF_Recursive)!=0 ){ p = p->pPrior; } + return p!=0; +} + +/* ** This routine is called to process a compound query form from ** two or more separate queries using UNION, UNION ALL, EXCEPT, or ** INTERSECT ** ** "p" points to the right-most of the two queries. the query on the ** left is p->pPrior. The left query could also be a compound query -** in which case this routine will be called recursively. +** in which case this routine will be called recursively. ** ** The results of the total query are to be written into a destination ** of type eDest with parameter iParm. @@ -2552,12 +2880,8 @@ static int multiSelect( db = pParse->db; pPrior = p->pPrior; dest = *pDest; - if( pPrior->pOrderBy || pPrior->pLimit ){ - sqlite3ErrorMsg(pParse,"%s clause should come after %s not before", - pPrior->pOrderBy!=0 ? "ORDER BY" : "LIMIT", selectOpName(p->op)); - rc = 1; - goto multi_select_end; - } + assert( pPrior->pOrderBy==0 ); + assert( pPrior->pLimit==0 ); v = sqlite3GetVdbe(pParse); assert( v!=0 ); /* The VDBE already created by calling function */ @@ -2585,7 +2909,7 @@ static int multiSelect( assert( p->pEList->nExpr==pPrior->pEList->nExpr ); #ifndef SQLITE_OMIT_CTE - if( p->selFlags & SF_Recursive ){ + if( (p->selFlags & SF_Recursive)!=0 && hasAnchor(p) ){ generateWithRecursiveQuery(pParse, p, &dest); }else #endif @@ -2608,13 +2932,14 @@ static int multiSelect( switch( p->op ){ case TK_ALL: { int addr = 0; - int nLimit; + int nLimit = 0; /* Initialize to suppress harmless compiler warning */ assert( !pPrior->pLimit ); pPrior->iLimit = p->iLimit; pPrior->iOffset = p->iOffset; pPrior->pLimit = p->pLimit; + TREETRACE(0x200, pParse, p, ("multiSelect UNION ALL left...\n")); rc = sqlite3Select(pParse, pPrior, &dest); - p->pLimit = 0; + pPrior->pLimit = 0; if( rc ){ goto multi_select_end; } @@ -2630,14 +2955,15 @@ static int multiSelect( } } ExplainQueryPlan((pParse, 1, "UNION ALL")); + TREETRACE(0x200, pParse, p, ("multiSelect UNION ALL right...\n")); rc = sqlite3Select(pParse, p, &dest); testcase( rc!=SQLITE_OK ); pDelete = p->pPrior; p->pPrior = pPrior; p->nSelectRow = sqlite3LogEstAdd(p->nSelectRow, pPrior->nSelectRow); - if( pPrior->pLimit - && sqlite3ExprIsInteger(pPrior->pLimit->pLeft, &nLimit) - && nLimit>0 && p->nSelectRow > sqlite3LogEst((u64)nLimit) + if( p->pLimit + && sqlite3ExprIsInteger(p->pLimit->pLeft, &nLimit) + && nLimit>0 && p->nSelectRow > sqlite3LogEst((u64)nLimit) ){ p->nSelectRow = sqlite3LogEst((u64)nLimit); } @@ -2654,7 +2980,7 @@ static int multiSelect( Expr *pLimit; /* Saved values of p->nLimit */ int addr; SelectDest uniondest; - + testcase( p->op==TK_EXCEPT ); testcase( p->op==TK_UNION ); priorOp = SRT_Union; @@ -2676,16 +3002,18 @@ static int multiSelect( findRightmost(p)->selFlags |= SF_UsesEphemeral; assert( p->pEList ); } - + + /* Code the SELECT statements to our left */ assert( !pPrior->pOrderBy ); sqlite3SelectDestInit(&uniondest, priorOp, unionTab); + TREETRACE(0x200, pParse, p, ("multiSelect EXCEPT/UNION left...\n")); rc = sqlite3Select(pParse, pPrior, &uniondest); if( rc ){ goto multi_select_end; } - + /* Code the current SELECT statement */ if( p->op==TK_EXCEPT ){ @@ -2699,7 +3027,8 @@ static int multiSelect( p->pLimit = 0; uniondest.eDest = op; ExplainQueryPlan((pParse, 1, "%s USING TEMP B-TREE", - selectOpName(p->op))); + sqlite3SelectOpName(p->op))); + TREETRACE(0x200, pParse, p, ("multiSelect EXCEPT/UNION right...\n")); rc = sqlite3Select(pParse, p, &uniondest); testcase( rc!=SQLITE_OK ); assert( p->pOrderBy==0 ); @@ -2713,7 +3042,7 @@ static int multiSelect( p->pLimit = pLimit; p->iLimit = 0; p->iOffset = 0; - + /* Convert the data in the temporary table into whatever form ** it is that we currently need. */ @@ -2742,7 +3071,7 @@ static int multiSelect( int addr; SelectDest intersectdest; int r1; - + /* INTERSECT is different from the others since it requires ** two temporary tables. Hence it has its own case. Begin ** by allocating the tables we will need. @@ -2750,21 +3079,22 @@ static int multiSelect( tab1 = pParse->nTab++; tab2 = pParse->nTab++; assert( p->pOrderBy==0 ); - + addr = sqlite3VdbeAddOp2(v, OP_OpenEphemeral, tab1, 0); assert( p->addrOpenEphm[0] == -1 ); p->addrOpenEphm[0] = addr; findRightmost(p)->selFlags |= SF_UsesEphemeral; assert( p->pEList ); - + /* Code the SELECTs to our left into temporary table "tab1". */ sqlite3SelectDestInit(&intersectdest, SRT_Union, tab1); + TREETRACE(0x400, pParse, p, ("multiSelect INTERSECT left...\n")); rc = sqlite3Select(pParse, pPrior, &intersectdest); if( rc ){ goto multi_select_end; } - + /* Code the current SELECT into temporary table "tab2" */ addr = sqlite3VdbeAddOp2(v, OP_OpenEphemeral, tab2, 0); @@ -2775,7 +3105,8 @@ static int multiSelect( p->pLimit = 0; intersectdest.iSDParm = tab2; ExplainQueryPlan((pParse, 1, "%s USING TEMP B-TREE", - selectOpName(p->op))); + sqlite3SelectOpName(p->op))); + TREETRACE(0x400, pParse, p, ("multiSelect INTERSECT right...\n")); rc = sqlite3Select(pParse, p, &intersectdest); testcase( rc!=SQLITE_OK ); pDelete = p->pPrior; @@ -2785,7 +3116,7 @@ static int multiSelect( } sqlite3ExprDelete(db, p->pLimit); p->pLimit = pLimit; - + /* Generate code to take the intersection of the two temporary ** tables. */ @@ -2810,7 +3141,7 @@ static int multiSelect( break; } } - + #ifndef SQLITE_OMIT_EXPLAIN if( p->pNext==0 ){ ExplainQueryPlanPop(pParse); @@ -2818,8 +3149,8 @@ static int multiSelect( #endif } if( pParse->nErr ) goto multi_select_end; - - /* Compute collating sequences used by + + /* Compute collating sequences used by ** temporary tables needed to implement the compound select. ** Attach the KeyInfo structure to all temporary tables. ** @@ -2836,6 +3167,7 @@ static int multiSelect( int nCol; /* Number of columns in result set */ assert( p->pNext==0 ); + assert( p->pEList!=0 ); nCol = p->pEList->nExpr; pKeyInfo = sqlite3KeyInfoAlloc(db, nCol, 1); if( !pKeyInfo ){ @@ -2870,7 +3202,11 @@ static int multiSelect( multi_select_end: pDest->iSdst = dest.iSdst; pDest->nSdst = dest.nSdst; - sqlite3SelectDelete(db, pDelete); + if( pDelete ){ + sqlite3ParserAddCleanup(pParse, + (void(*)(sqlite3*,void*))sqlite3SelectDelete, + pDelete); + } return rc; } #endif /* SQLITE_OMIT_COMPOUND_SELECT */ @@ -2884,13 +3220,14 @@ void sqlite3SelectWrongNumTermsError(Parse *pParse, Select *p){ sqlite3ErrorMsg(pParse, "all VALUES must have the same number of terms"); }else{ sqlite3ErrorMsg(pParse, "SELECTs to the left and right of %s" - " do not have the same number of result columns", selectOpName(p->op)); + " do not have the same number of result columns", + sqlite3SelectOpName(p->op)); } } /* ** Code an output subroutine for a coroutine implementation of a -** SELECT statment. +** SELECT statement. ** ** The data to be output is contained in pIn->iSdst. There are ** pIn->nSdst columns to be output. pDest is where the output should @@ -2925,7 +3262,7 @@ static int generateOutputSubroutine( addr = sqlite3VdbeCurrentAddr(v); iContinue = sqlite3VdbeMakeLabel(pParse); - /* Suppress duplicates for UNION, EXCEPT, and INTERSECT + /* Suppress duplicates for UNION, EXCEPT, and INTERSECT */ if( regPrev ){ int addr1, addr2; @@ -2967,7 +3304,7 @@ static int generateOutputSubroutine( int r1; testcase( pIn->nSdst>1 ); r1 = sqlite3GetTempReg(pParse); - sqlite3VdbeAddOp4(v, OP_MakeRecord, pIn->iSdst, pIn->nSdst, + sqlite3VdbeAddOp4(v, OP_MakeRecord, pIn->iSdst, pIn->nSdst, r1, pDest->zAffSdst, pIn->nSdst); sqlite3VdbeAddOp4Int(v, OP_IdxInsert, pDest->iSDParm, r1, pIn->iSdst, pIn->nSdst); @@ -2981,10 +3318,8 @@ static int generateOutputSubroutine( ** if it is the RHS of a row-value IN operator. */ case SRT_Mem: { - if( pParse->nErr==0 ){ - testcase( pIn->nSdst>1 ); - sqlite3ExprCodeMove(pParse, pIn->iSdst, pDest->iSDParm, pIn->nSdst); - } + testcase( pIn->nSdst>1 ); + sqlite3ExprCodeMove(pParse, pIn->iSdst, pDest->iSDParm, pIn->nSdst); /* The LIMIT clause will jump out of the loop for us */ break; } @@ -3007,7 +3342,7 @@ static int generateOutputSubroutine( ** 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. + ** 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. */ @@ -3064,7 +3399,7 @@ static int generateOutputSubroutine( ** ** EofB: Called when data is exhausted from selectB. ** -** The implementation of the latter five subroutines depend on which +** The implementation of the latter five subroutines depend on which ** <operator> is used: ** ** @@ -3114,7 +3449,7 @@ static int generateOutputSubroutine( ** ** We call AltB, AeqB, AgtB, EofA, and EofB "subroutines" but they are not ** actually called using Gosub and they do not Return. EofA and EofB loop -** until all data is exhausted then jump to the "end" labe. AltB, AeqB, +** until all data is exhausted then jump to the "end" label. AltB, AeqB, ** and AgtB jump to either L2 or to one of EofA or EofB. */ #ifndef SQLITE_OMIT_COMPOUND_SELECT @@ -3125,6 +3460,8 @@ static int multiSelectOrderBy( ){ int i, j; /* Loop counters */ Select *pPrior; /* Another SELECT immediately to our left */ + Select *pSplit; /* Left-most SELECT in the right-hand group */ + int nSelect; /* Number of SELECT statements in the compound */ Vdbe *v; /* Generate code to this VDBE */ SelectDest destA; /* Destination for coroutine A */ SelectDest destB; /* Destination for coroutine B */ @@ -3149,14 +3486,14 @@ static int multiSelectOrderBy( int savedOffset; /* Saved value of p->iOffset */ int labelCmpr; /* Label for the start of the merge algorithm */ int labelEnd; /* Label for the end of the overall SELECT stmt */ - int addr1; /* Jump instructions that get retargetted */ + int addr1; /* Jump instructions that get retargeted */ int op; /* One of TK_ALL, TK_UNION, TK_EXCEPT, TK_INTERSECT */ 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 */ + u32 *aPermute; /* Mapping from ORDER BY terms to result set columns */ assert( p->pOrderBy!=0 ); assert( pKeyDup==0 ); /* "Managed" code needs this. Ticket #3382. */ @@ -3169,9 +3506,8 @@ static int multiSelectOrderBy( /* Patch up the ORDER BY clause */ - op = p->op; - pPrior = p->pPrior; - assert( pPrior->pOrderBy==0 ); + op = p->op; + assert( p->pPrior->pOrderBy==0 ); pOrderBy = p->pOrderBy; assert( pOrderBy ); nOrderBy = pOrderBy->nExpr; @@ -3184,6 +3520,7 @@ static int multiSelectOrderBy( for(i=1; db->mallocFailed==0 && i<=p->pEList->nExpr; i++){ struct ExprList_item *pItem; for(j=0, pItem=pOrderBy->a; j<nOrderBy; j++, pItem++){ + assert( pItem!=0 ); assert( pItem->u.x.iOrderByCol>0 ); if( pItem->u.x.iOrderByCol==i ) break; } @@ -3205,11 +3542,12 @@ static int multiSelectOrderBy( ** to the right and the left are evaluated, they use the correct ** collation. */ - aPermute = sqlite3DbMallocRawNN(db, sizeof(int)*(nOrderBy + 1)); + aPermute = sqlite3DbMallocRawNN(db, sizeof(u32)*(nOrderBy + 1)); if( aPermute ){ struct ExprList_item *pItem; aPermute[0] = nOrderBy; for(i=1, pItem=pOrderBy->a; i<=nOrderBy; i++, pItem++){ + assert( pItem!=0 ); assert( pItem->u.x.iOrderByCol>0 ); assert( pItem->u.x.iOrderByCol<=p->pEList->nExpr ); aPermute[i] = pItem->u.x.iOrderByCol - 1; @@ -3219,11 +3557,6 @@ static int multiSelectOrderBy( pKeyMerge = 0; } - /* Reattach the ORDER BY clause to the query. - */ - p->pOrderBy = 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 ** operator is UNION, EXCEPT, or INTERSECT (but not UNION ALL). @@ -3245,15 +3578,33 @@ static int multiSelectOrderBy( } } } - + /* Separate the left and the right query from one another */ - p->pPrior = 0; + nSelect = 1; + if( (op==TK_ALL || op==TK_UNION) + && OptimizationEnabled(db, SQLITE_BalancedMerge) + ){ + for(pSplit=p; pSplit->pPrior!=0 && pSplit->op==op; pSplit=pSplit->pPrior){ + nSelect++; + assert( pSplit->pPrior->pNext==pSplit ); + } + } + if( nSelect<=3 ){ + pSplit = p; + }else{ + pSplit = p; + for(i=2; i<nSelect; i+=2){ pSplit = pSplit->pPrior; } + } + pPrior = pSplit->pPrior; + assert( pPrior!=0 ); + pSplit->pPrior = 0; pPrior->pNext = 0; + assert( p->pOrderBy == pOrderBy ); + assert( pOrderBy!=0 || db->mallocFailed ); + pPrior->pOrderBy = sqlite3ExprListDup(pParse->db, pOrderBy, 0); sqlite3ResolveOrderGroupBy(pParse, p, p->pOrderBy, "ORDER"); - if( pPrior->pPrior==0 ){ - sqlite3ResolveOrderGroupBy(pParse, pPrior, pPrior->pOrderBy, "ORDER"); - } + sqlite3ResolveOrderGroupBy(pParse, pPrior, pPrior->pOrderBy, "ORDER"); /* Compute the limit registers */ computeLimitRegisters(pParse, p, labelEnd); @@ -3276,7 +3627,7 @@ static int multiSelectOrderBy( sqlite3SelectDestInit(&destA, SRT_Coroutine, regAddrA); sqlite3SelectDestInit(&destB, SRT_Coroutine, regAddrB); - ExplainQueryPlan((pParse, 1, "MERGE (%s)", selectOpName(p->op))); + ExplainQueryPlan((pParse, 1, "MERGE (%s)", sqlite3SelectOpName(p->op))); /* Generate a coroutine to evaluate the SELECT statement to the ** left of the compound operator - the "A" select. @@ -3290,7 +3641,7 @@ static int multiSelectOrderBy( sqlite3VdbeEndCoroutine(v, regAddrA); sqlite3VdbeJumpHere(v, addr1); - /* Generate a coroutine to evaluate the SELECT statement on + /* Generate a coroutine to evaluate the SELECT statement on ** the right - the "B" select */ addrSelectB = sqlite3VdbeCurrentAddr(v) + 1; @@ -3299,7 +3650,7 @@ static int multiSelectOrderBy( savedLimit = p->iLimit; savedOffset = p->iOffset; p->iLimit = regLimitB; - p->iOffset = 0; + p->iOffset = 0; ExplainQueryPlan((pParse, 1, "RIGHT")); sqlite3Select(pParse, p, &destB); p->iLimit = savedLimit; @@ -3313,7 +3664,7 @@ static int multiSelectOrderBy( addrOutA = generateOutputSubroutine(pParse, p, &destA, pDest, regOutA, regPrev, pKeyDup, labelEnd); - + /* Generate a subroutine that outputs the current row of the B ** select as the next output row of the compound select. */ @@ -3330,7 +3681,7 @@ static int multiSelectOrderBy( */ if( op==TK_EXCEPT || op==TK_INTERSECT ){ addrEofA_noB = addrEofA = labelEnd; - }else{ + }else{ VdbeNoopComment((v, "eof-A subroutine")); addrEofA = sqlite3VdbeAddOp2(v, OP_Gosub, regOutB, addrOutB); addrEofA_noB = sqlite3VdbeAddOp2(v, OP_Yield, regAddrB, labelEnd); @@ -3345,7 +3696,7 @@ static int multiSelectOrderBy( if( op==TK_INTERSECT ){ addrEofB = addrEofA; if( p->nSelectRow > pPrior->nSelectRow ) p->nSelectRow = pPrior->nSelectRow; - }else{ + }else{ VdbeNoopComment((v, "eof-B subroutine")); addrEofB = sqlite3VdbeAddOp2(v, OP_Gosub, regOutA, addrOutA); sqlite3VdbeAddOp2(v, OP_Yield, regAddrA, labelEnd); VdbeCoverage(v); @@ -3402,13 +3753,16 @@ static int multiSelectOrderBy( */ sqlite3VdbeResolveLabel(v, labelEnd); - /* Reassembly the compound query so that it will be freed correctly - ** by the calling function */ - if( p->pPrior ){ - sqlite3SelectDelete(db, p->pPrior); + /* Make arrangements to free the 2nd and subsequent arms of the compound + ** after the parse has finished */ + if( pSplit->pPrior ){ + sqlite3ParserAddCleanup(pParse, + (void(*)(sqlite3*,void*))sqlite3SelectDelete, pSplit->pPrior); } - p->pPrior = pPrior; - pPrior->pNext = p; + pSplit->pPrior = pPrior; + pPrior->pNext = pSplit; + sqlite3ExprListDelete(db, pPrior->pOrderBy); + pPrior->pOrderBy = 0; /*** TBD: Insert subroutine calls to close cursors on incomplete **** subqueries ****/ @@ -3424,13 +3778,42 @@ static int multiSelectOrderBy( ** ** All references to columns in table iTable are to be replaced by corresponding ** expressions in pEList. +** +** ## About "isOuterJoin": +** +** The isOuterJoin column indicates that the replacement will occur into a +** position in the parent that NULL-able due to an OUTER JOIN. Either the +** target slot in the parent is the right operand of a LEFT JOIN, or one of +** the left operands of a RIGHT JOIN. In either case, we need to potentially +** bypass the substituted expression with OP_IfNullRow. +** +** Suppose the original expression is an integer constant. Even though the table +** has the nullRow flag set, because the expression is an integer constant, +** it will not be NULLed out. So instead, we insert an OP_IfNullRow opcode +** that checks to see if the nullRow flag is set on the table. If the nullRow +** flag is set, then the value in the register is set to NULL and the original +** expression is bypassed. If the nullRow flag is not set, then the original +** expression runs to populate the register. +** +** Example where this is needed: +** +** CREATE TABLE t1(a INTEGER PRIMARY KEY, b INT); +** CREATE TABLE t2(x INT UNIQUE); +** +** SELECT a,b,m,x FROM t1 LEFT JOIN (SELECT 59 AS m,x FROM t2) ON b=x; +** +** When the subquery on the right side of the LEFT JOIN is flattened, we +** have to add OP_IfNullRow in front of the OP_Integer that implements the +** "m" value of the subquery so that a NULL will be loaded instead of 59 +** when processing a non-matched row of the left. */ typedef struct SubstContext { Parse *pParse; /* The parsing context */ int iTable; /* Replace references to this table */ int iNewTable; /* New table number */ - int isLeftJoin; /* Add TK_IF_NULL_ROW opcodes on each replacement */ + int isOuterJoin; /* Add TK_IF_NULL_ROW opcodes on each replacement */ ExprList *pEList; /* Replacement expressions */ + ExprList *pCList; /* Collation sequences for replacement expr */ } SubstContext; /* Forward Declarations */ @@ -3440,13 +3823,13 @@ static void substSelect(SubstContext*, Select*, int); /* ** Scan through the expression pExpr. Replace every reference to ** a column in table number iTable with a copy of the iColumn-th -** entry in pEList. (But leave references to the ROWID column +** entry in pEList. (But leave references to the ROWID column ** unchanged.) ** ** This routine is part of the flattening procedure. A subquery ** whose result set is defined by pEList appears as entry in the ** FROM clause of a SELECT such that the VDBE cursor assigned to that -** FORM clause entry is iTable. This routine makes the necessary +** FORM clause entry is iTable. This routine makes the necessary ** changes to pExpr so that it refers directly to the source table ** of the subquery rather the result set of the subquery. */ @@ -3455,58 +3838,81 @@ static Expr *substExpr( Expr *pExpr /* Expr in which substitution occurs */ ){ if( pExpr==0 ) return 0; - if( ExprHasProperty(pExpr, EP_FromJoin) - && pExpr->iRightJoinTable==pSubst->iTable + if( ExprHasProperty(pExpr, EP_OuterON|EP_InnerON) + && pExpr->w.iJoin==pSubst->iTable ){ - pExpr->iRightJoinTable = pSubst->iNewTable; + testcase( ExprHasProperty(pExpr, EP_InnerON) ); + pExpr->w.iJoin = pSubst->iNewTable; } if( pExpr->op==TK_COLUMN && pExpr->iTable==pSubst->iTable && !ExprHasProperty(pExpr, EP_FixedCol) ){ +#ifdef SQLITE_ALLOW_ROWID_IN_VIEW if( pExpr->iColumn<0 ){ pExpr->op = TK_NULL; - }else{ + }else +#endif + { Expr *pNew; - Expr *pCopy = pSubst->pEList->a[pExpr->iColumn].pExpr; + int iColumn; + Expr *pCopy; Expr ifNullRow; - assert( pSubst->pEList!=0 && pExpr->iColumn<pSubst->pEList->nExpr ); + iColumn = pExpr->iColumn; + assert( iColumn>=0 ); + assert( pSubst->pEList!=0 && iColumn<pSubst->pEList->nExpr ); assert( pExpr->pRight==0 ); + pCopy = pSubst->pEList->a[iColumn].pExpr; if( sqlite3ExprIsVector(pCopy) ){ sqlite3VectorErrorMsg(pSubst->pParse, pCopy); }else{ sqlite3 *db = pSubst->pParse->db; - if( pSubst->isLeftJoin && pCopy->op!=TK_COLUMN ){ + if( pSubst->isOuterJoin + && (pCopy->op!=TK_COLUMN || pCopy->iTable!=pSubst->iNewTable) + ){ memset(&ifNullRow, 0, sizeof(ifNullRow)); ifNullRow.op = TK_IF_NULL_ROW; ifNullRow.pLeft = pCopy; ifNullRow.iTable = pSubst->iNewTable; - ifNullRow.flags = EP_Skip; + ifNullRow.iColumn = -99; + ifNullRow.flags = EP_IfNullRow; pCopy = &ifNullRow; } testcase( ExprHasProperty(pCopy, EP_Subquery) ); pNew = sqlite3ExprDup(db, pCopy, 0); - if( pNew && pSubst->isLeftJoin ){ + if( db->mallocFailed ){ + sqlite3ExprDelete(db, pNew); + return pExpr; + } + if( pSubst->isOuterJoin ){ ExprSetProperty(pNew, EP_CanBeNull); } - if( pNew && ExprHasProperty(pExpr,EP_FromJoin) ){ - pNew->iRightJoinTable = pExpr->iRightJoinTable; - ExprSetProperty(pNew, EP_FromJoin); + if( ExprHasProperty(pExpr,EP_OuterON|EP_InnerON) ){ + sqlite3SetJoinExpr(pNew, pExpr->w.iJoin, + pExpr->flags & (EP_OuterON|EP_InnerON)); } sqlite3ExprDelete(db, pExpr); pExpr = pNew; + if( pExpr->op==TK_TRUEFALSE ){ + pExpr->u.iValue = sqlite3ExprTruthValue(pExpr); + pExpr->op = TK_INTEGER; + ExprSetProperty(pExpr, EP_IntValue); + } /* Ensure that the expression now has an implicit collation sequence, ** just as it did when it was a column of a view or sub-query. */ - if( pExpr ){ - if( pExpr->op!=TK_COLUMN && pExpr->op!=TK_COLLATE ){ - CollSeq *pColl = sqlite3ExprCollSeq(pSubst->pParse, pExpr); - pExpr = sqlite3ExprAddCollateString(pSubst->pParse, pExpr, + { + CollSeq *pNat = sqlite3ExprCollSeq(pSubst->pParse, pExpr); + CollSeq *pColl = sqlite3ExprCollSeq(pSubst->pParse, + pSubst->pCList->a[iColumn].pExpr + ); + if( pNat!=pColl || (pExpr->op!=TK_COLUMN && pExpr->op!=TK_COLLATE) ){ + pExpr = sqlite3ExprAddCollateString(pSubst->pParse, pExpr, (pColl ? pColl->zName : "BINARY") ); } - ExprClearProperty(pExpr, EP_Collate); } + ExprClearProperty(pExpr, EP_Collate); } } }else{ @@ -3515,7 +3921,7 @@ static Expr *substExpr( } pExpr->pLeft = substExpr(pSubst, pExpr->pLeft); pExpr->pRight = substExpr(pSubst, pExpr->pRight); - if( ExprHasProperty(pExpr, EP_xIsSelect) ){ + if( ExprUseXSelect(pExpr) ){ substSelect(pSubst, pExpr->x.pSelect, 1); }else{ substExprList(pSubst, pExpr->x.pList); @@ -3547,7 +3953,7 @@ static void substSelect( int doPrior /* Do substitutes on p->pPrior too */ ){ SrcList *pSrc; - struct SrcList_item *pItem; + SrcItem *pItem; int i; if( !p ) return; do{ @@ -3577,7 +3983,7 @@ static void substSelect( ** pSrcItem->colUsed mask. */ static int recomputeColumnsUsedExpr(Walker *pWalker, Expr *pExpr){ - struct SrcList_item *pItem; + SrcItem *pItem; if( pExpr->op!=TK_COLUMN ) return WRC_Continue; pItem = pWalker->u.pSrcItem; if( pItem->iCursor!=pExpr->iTable ) return WRC_Continue; @@ -3587,7 +3993,7 @@ static int recomputeColumnsUsedExpr(Walker *pWalker, Expr *pExpr){ } static void recomputeColumnsUsed( Select *pSelect, /* The complete SELECT statement */ - struct SrcList_item *pSrcItem /* Which FROM clause item to recompute */ + SrcItem *pSrcItem /* Which FROM clause item to recompute */ ){ Walker w; if( NEVER(pSrcItem->pTab==0) ) return; @@ -3602,6 +4008,143 @@ static void recomputeColumnsUsed( #if !defined(SQLITE_OMIT_SUBQUERY) || !defined(SQLITE_OMIT_VIEW) /* +** Assign new cursor numbers to each of the items in pSrc. For each +** new cursor number assigned, set an entry in the aCsrMap[] array +** to map the old cursor number to the new: +** +** aCsrMap[iOld+1] = iNew; +** +** The array is guaranteed by the caller to be large enough for all +** existing cursor numbers in pSrc. aCsrMap[0] is the array size. +** +** If pSrc contains any sub-selects, call this routine recursively +** on the FROM clause of each such sub-select, with iExcept set to -1. +*/ +static void srclistRenumberCursors( + Parse *pParse, /* Parse context */ + int *aCsrMap, /* Array to store cursor mappings in */ + SrcList *pSrc, /* FROM clause to renumber */ + int iExcept /* FROM clause item to skip */ +){ + int i; + SrcItem *pItem; + for(i=0, pItem=pSrc->a; i<pSrc->nSrc; i++, pItem++){ + if( i!=iExcept ){ + Select *p; + assert( pItem->iCursor < aCsrMap[0] ); + if( !pItem->fg.isRecursive || aCsrMap[pItem->iCursor+1]==0 ){ + aCsrMap[pItem->iCursor+1] = pParse->nTab++; + } + pItem->iCursor = aCsrMap[pItem->iCursor+1]; + for(p=pItem->pSelect; p; p=p->pPrior){ + srclistRenumberCursors(pParse, aCsrMap, p->pSrc, -1); + } + } + } +} + +/* +** *piCursor is a cursor number. Change it if it needs to be mapped. +*/ +static void renumberCursorDoMapping(Walker *pWalker, int *piCursor){ + int *aCsrMap = pWalker->u.aiCol; + int iCsr = *piCursor; + if( iCsr < aCsrMap[0] && aCsrMap[iCsr+1]>0 ){ + *piCursor = aCsrMap[iCsr+1]; + } +} + +/* +** Expression walker callback used by renumberCursors() to update +** Expr objects to match newly assigned cursor numbers. +*/ +static int renumberCursorsCb(Walker *pWalker, Expr *pExpr){ + int op = pExpr->op; + if( op==TK_COLUMN || op==TK_IF_NULL_ROW ){ + renumberCursorDoMapping(pWalker, &pExpr->iTable); + } + if( ExprHasProperty(pExpr, EP_OuterON) ){ + renumberCursorDoMapping(pWalker, &pExpr->w.iJoin); + } + return WRC_Continue; +} + +/* +** Assign a new cursor number to each cursor in the FROM clause (Select.pSrc) +** of the SELECT statement passed as the second argument, and to each +** cursor in the FROM clause of any FROM clause sub-selects, recursively. +** Except, do not assign a new cursor number to the iExcept'th element in +** the FROM clause of (*p). Update all expressions and other references +** to refer to the new cursor numbers. +** +** Argument aCsrMap is an array that may be used for temporary working +** space. Two guarantees are made by the caller: +** +** * the array is larger than the largest cursor number used within the +** select statement passed as an argument, and +** +** * the array entries for all cursor numbers that do *not* appear in +** FROM clauses of the select statement as described above are +** initialized to zero. +*/ +static void renumberCursors( + Parse *pParse, /* Parse context */ + Select *p, /* Select to renumber cursors within */ + int iExcept, /* FROM clause item to skip */ + int *aCsrMap /* Working space */ +){ + Walker w; + srclistRenumberCursors(pParse, aCsrMap, p->pSrc, iExcept); + memset(&w, 0, sizeof(w)); + w.u.aiCol = aCsrMap; + w.xExprCallback = renumberCursorsCb; + w.xSelectCallback = sqlite3SelectWalkNoop; + sqlite3WalkSelect(&w, p); +} +#endif /* !defined(SQLITE_OMIT_SUBQUERY) || !defined(SQLITE_OMIT_VIEW) */ + +/* +** If pSel is not part of a compound SELECT, return a pointer to its +** expression list. Otherwise, return a pointer to the expression list +** of the leftmost SELECT in the compound. +*/ +static ExprList *findLeftmostExprlist(Select *pSel){ + while( pSel->pPrior ){ + pSel = pSel->pPrior; + } + return pSel->pEList; +} + +/* +** Return true if any of the result-set columns in the compound query +** have incompatible affinities on one or more arms of the compound. +*/ +static int compoundHasDifferentAffinities(Select *p){ + int ii; + ExprList *pList; + assert( p!=0 ); + assert( p->pEList!=0 ); + assert( p->pPrior!=0 ); + pList = p->pEList; + for(ii=0; ii<pList->nExpr; ii++){ + char aff; + Select *pSub1; + assert( pList->a[ii].pExpr!=0 ); + aff = sqlite3ExprAffinity(pList->a[ii].pExpr); + for(pSub1=p->pPrior; pSub1; pSub1=pSub1->pPrior){ + assert( pSub1->pEList!=0 ); + assert( pSub1->pEList->nExpr>ii ); + assert( pSub1->pEList->a[ii].pExpr!=0 ); + if( sqlite3ExprAffinity(pSub1->pEList->a[ii].pExpr)!=aff ){ + return 1; + } + } + } + return 0; +} + +#if !defined(SQLITE_OMIT_SUBQUERY) || !defined(SQLITE_OMIT_VIEW) +/* ** This routine attempts to flatten subqueries as a performance optimization. ** This routine returns 1 if it makes changes and 0 if no flattening occurs. ** @@ -3623,7 +4166,7 @@ static void recomputeColumnsUsed( ** SELECT x+y AS a FROM t1 WHERE z<100 AND a>5 ** ** The code generated for this simplification gives the same result -** but only has to scan the data once. And because indices might +** but only has to scan the data once. And because indices might ** exist on the table t1, a complete scan of the data might be ** avoided. ** @@ -3644,13 +4187,15 @@ static void recomputeColumnsUsed( ** (3a) the subquery may not be a join and ** (3b) the FROM clause of the subquery may not contain a virtual ** table and -** (3c) the outer query may not be an aggregate. +** (**) Was: "The outer query may not have a GROUP BY." This case +** is now managed correctly ** (3d) the outer query may not be DISTINCT. +** See also (26) for restrictions on RIGHT JOIN. ** ** (4) The subquery can not be DISTINCT. ** ** (**) At one point restrictions (4) and (5) defined a subset of DISTINCT -** sub-queries that were excluded from this optimization. Restriction +** sub-queries that were excluded from this optimization. Restriction ** (4) has since been expanded to exclude all DISTINCT subqueries. ** ** (**) We no longer attempt to flatten aggregate subqueries. Was: @@ -3666,8 +4211,8 @@ static void recomputeColumnsUsed( ** (9) If the subquery uses LIMIT then the outer query may not be aggregate. ** ** (**) Restriction (10) was removed from the code on 2005-02-05 but we -** accidently carried the comment forward until 2014-09-15. Original -** constraint: "If the subquery is aggregate then the outer query +** accidentally carried the comment forward until 2014-09-15. Original +** constraint: "If the subquery is aggregate then the outer query ** may not use LIMIT." ** ** (11) The subquery and the outer query may not both have ORDER BY clauses. @@ -3685,7 +4230,7 @@ static void recomputeColumnsUsed( ** ** (16) If the outer query is aggregate, then the subquery may not ** use ORDER BY. (Ticket #2942) This used to not matter -** until we introduced the group_concat() function. +** until we introduced the group_concat() function. ** ** (17) If the subquery is a compound select, then ** (17a) all compound operators must be a UNION ALL, and @@ -3694,9 +4239,14 @@ static void recomputeColumnsUsed( ** (17c) every term within the subquery compound must have a FROM clause ** (17d) the outer query may not be ** (17d1) aggregate, or -** (17d2) DISTINCT, or -** (17d3) a join. -** (17e) the subquery may not contain window functions +** (17d2) DISTINCT +** (17e) the subquery may not contain window functions, and +** (17f) the subquery must not be the RHS of a LEFT JOIN. +** (17g) either the subquery is the first element of the outer +** query or there are no RIGHT or FULL JOINs in any arm +** of the subquery. (This is a duplicate of condition (27b).) +** (17h) The corresponding result set expressions in all arms of the +** compound must have the same affinity. ** ** The parent and sub-query may contain WHERE clauses. Subject to ** rules (11), (13) and (14), they may also contain ORDER BY, @@ -3712,8 +4262,8 @@ static void recomputeColumnsUsed( ** syntax error and return a detailed message. ** ** (18) If the sub-query is a compound select, then all terms of the -** ORDER BY clause of the parent must be simple references to -** columns of the sub-query. +** ORDER BY clause of the parent must be copies of a term returned +** by the parent query. ** ** (19) If the subquery uses LIMIT then the outer query may not ** have a WHERE clause. @@ -3729,14 +4279,13 @@ static void recomputeColumnsUsed( ** ** (22) The subquery may not be a recursive CTE. ** -** (**) Subsumed into restriction (17d3). Was: If the outer query is -** a recursive CTE, then the sub-query may not be a compound query. -** This restriction is because transforming the +** (23) If the outer query is a recursive CTE, then the sub-query may not be +** a compound query. This restriction is because transforming the ** parent to a compound query confuses the code that handles ** recursive queries in multiSelect(). ** ** (**) We no longer attempt to flatten aggregate subqueries. Was: -** The subquery may not be an aggregate that uses the built-in min() or +** The subquery may not be an aggregate that uses the built-in min() or ** or max() functions. (Without this restriction, a query like: ** "SELECT x FROM (SELECT max(y), x FROM t1)" would not necessarily ** return the value X for which Y was maximal.) @@ -3745,6 +4294,18 @@ static void recomputeColumnsUsed( ** function in the select list or ORDER BY clause, flattening ** is not attempted. ** +** (26) The subquery may not be the right operand of a RIGHT JOIN. +** See also (3) for restrictions on LEFT JOIN. +** +** (27) The subquery may not contain a FULL or RIGHT JOIN unless it +** is the first element of the parent query. Two subcases: +** (27a) the subquery is not a compound query. +** (27b) the subquery is a compound query and the RIGHT JOIN occurs +** in any arm of the compound query. (See also (17g).) +** +** (28) The subquery is not a MATERIALIZED CTE. (This is handled +** in the caller before ever reaching this routine.) +** ** ** 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 @@ -3770,12 +4331,13 @@ static int flattenSubquery( SrcList *pSubSrc; /* The FROM clause of the subquery */ int iParent; /* VDBE cursor number of the pSub result set temp table */ int iNewParent = -1;/* Replacement table for iParent */ - int isLeftJoin = 0; /* True if pSub is the right side of a LEFT JOIN */ + int isOuterJoin = 0; /* True if pSub is the right side of a LEFT JOIN */ int i; /* Loop counter */ Expr *pWhere; /* The WHERE clause */ - struct SrcList_item *pSubitem; /* The subquery */ + SrcItem *pSubitem; /* The subquery */ sqlite3 *db = pParse->db; Walker w; /* Walker to persist agginfo data */ + int *aCsrMap = 0; /* Check to see if flattening is permitted. Return 0 if not. */ @@ -3835,32 +4397,26 @@ static int flattenSubquery( ** ** which is not at all the same thing. ** - ** If the subquery is the right operand of a LEFT JOIN, then the outer - ** query cannot be an aggregate. (3c) This is an artifact of the way - ** aggregates are processed - there is no mechanism to determine if - ** the LEFT JOIN table should be all-NULL. - ** ** See also tickets #306, #350, and #3300. */ - if( (pSubitem->fg.jointype & JT_OUTER)!=0 ){ - isLeftJoin = 1; - if( pSubSrc->nSrc>1 /* (3a) */ - || isAgg /* (3b) */ - || IsVirtual(pSubSrc->a[0].pTab) /* (3c) */ - || (p->selFlags & SF_Distinct)!=0 /* (3d) */ + if( (pSubitem->fg.jointype & (JT_OUTER|JT_LTORJ))!=0 ){ + if( pSubSrc->nSrc>1 /* (3a) */ + || IsVirtual(pSubSrc->a[0].pTab) /* (3b) */ + || (p->selFlags & SF_Distinct)!=0 /* (3d) */ + || (pSubitem->fg.jointype & JT_RIGHT)!=0 /* (26) */ ){ return 0; } + isOuterJoin = 1; } -#ifdef SQLITE_EXTRA_IFNULLROW - else if( iFrom>0 && !isAgg ){ - /* Setting isLeftJoin to -1 causes OP_IfNullRow opcodes to be generated for - ** every reference to any result column from subquery in a join, even - ** though they are not necessary. This will stress-test the OP_IfNullRow - ** opcode. */ - isLeftJoin = -1; + + assert( pSubSrc->nSrc>0 ); /* True by restriction (7) */ + if( iFrom>0 && (pSubSrc->a[0].fg.jointype & JT_LTORJ)!=0 ){ + return 0; /* Restriction (27a) */ } -#endif + + /* Condition (28) is blocked by the caller */ + assert( !pSubitem->fg.isCte || pSubitem->u2.pCteUse->eM10d!=M10d_Yes ); /* Restriction (17): If the sub-query is a compound SELECT, then it must ** use only the UNION ALL operator. And none of the simple select queries @@ -3868,16 +4424,18 @@ static int flattenSubquery( ** queries. */ if( pSub->pPrior ){ + int ii; if( pSub->pOrderBy ){ return 0; /* Restriction (20) */ } - if( isAgg || (p->selFlags & SF_Distinct)!=0 || pSrc->nSrc!=1 ){ - return 0; /* (17d1), (17d2), or (17d3) */ + if( isAgg || (p->selFlags & SF_Distinct)!=0 || isOuterJoin>0 ){ + return 0; /* (17d1), (17d2), or (17f) */ } for(pSub1=pSub; pSub1; pSub1=pSub1->pPrior){ testcase( (pSub1->selFlags & (SF_Distinct|SF_Aggregate))==SF_Distinct ); testcase( (pSub1->selFlags & (SF_Distinct|SF_Aggregate))==SF_Aggregate ); assert( pSub->pSrc!=0 ); + assert( (pSub->selFlags & SF_Recursive)==0 ); assert( pSub->pEList->nExpr==pSub1->pEList->nExpr ); if( (pSub1->selFlags & (SF_Distinct|SF_Aggregate))!=0 /* (17b) */ || (pSub1->pPrior && pSub1->op!=TK_ALL) /* (17a) */ @@ -3888,28 +4446,38 @@ static int flattenSubquery( ){ return 0; } + if( iFrom>0 && (pSub1->pSrc->a[0].fg.jointype & JT_LTORJ)!=0 ){ + /* Without this restriction, the JT_LTORJ flag would end up being + ** omitted on left-hand tables of the right join that is being + ** flattened. */ + return 0; /* Restrictions (17g), (27b) */ + } testcase( pSub1->pSrc->nSrc>1 ); } /* Restriction (18). */ if( p->pOrderBy ){ - int ii; for(ii=0; ii<p->pOrderBy->nExpr; ii++){ if( p->pOrderBy->a[ii].u.x.iOrderByCol==0 ) return 0; } } - } - /* Ex-restriction (23): - ** The only way that the recursive part of a CTE can contain a compound - ** subquery is for the subquery to be one term of a join. But if the - ** subquery is a join, then the flattening has already been stopped by - ** restriction (17d3) - */ - assert( (p->selFlags & SF_Recursive)==0 || pSub->pPrior==0 ); + /* Restriction (23) */ + if( (p->selFlags & SF_Recursive) ) return 0; + + /* Restriction (17h) */ + if( compoundHasDifferentAffinities(pSub) ) return 0; + + if( pSrc->nSrc>1 ){ + if( pParse->nSelect>500 ) return 0; + if( OptimizationDisabled(db, SQLITE_FlttnUnionAll) ) return 0; + aCsrMap = sqlite3DbMallocZero(db, ((i64)pParse->nTab+1)*sizeof(int)); + if( aCsrMap ) aCsrMap[0] = pParse->nTab; + } + } /***** If we reach this point, flattening is permitted. *****/ - SELECTTRACE(1,pParse,p,("flatten %u.%p from term %d\n", + TREETRACE(0x4,pParse,p,("flatten %u.%p from term %d\n", pSub->selId, pSub, iFrom)); /* Authorize the subquery */ @@ -3918,14 +4486,25 @@ static int flattenSubquery( testcase( i==SQLITE_DENY ); pParse->zAuthContext = zSavedAuthContext; + /* Delete the transient structures associated with the subquery */ + pSub1 = pSubitem->pSelect; + sqlite3DbFree(db, pSubitem->zDatabase); + sqlite3DbFree(db, pSubitem->zName); + sqlite3DbFree(db, pSubitem->zAlias); + pSubitem->zDatabase = 0; + pSubitem->zName = 0; + pSubitem->zAlias = 0; + pSubitem->pSelect = 0; + assert( pSubitem->fg.isUsing!=0 || pSubitem->u3.pOn==0 ); + /* 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 + ** 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> + ** SELECT <expr-list> FROM (<sub-query>) <where-clause> ** ** followed by any ORDER BY, LIMIT and/or OFFSET clauses. This block - ** creates N-1 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. @@ -3956,43 +4535,37 @@ static int flattenSubquery( ExprList *pOrderBy = p->pOrderBy; Expr *pLimit = p->pLimit; Select *pPrior = p->pPrior; + Table *pItemTab = pSubitem->pTab; + pSubitem->pTab = 0; p->pOrderBy = 0; - p->pSrc = 0; p->pPrior = 0; p->pLimit = 0; pNew = sqlite3SelectDup(db, p, 0); p->pLimit = pLimit; p->pOrderBy = pOrderBy; - p->pSrc = pSrc; p->op = TK_ALL; + pSubitem->pTab = pItemTab; if( pNew==0 ){ p->pPrior = pPrior; }else{ + pNew->selId = ++pParse->nSelect; + if( aCsrMap && ALWAYS(db->mallocFailed==0) ){ + renumberCursors(pParse, pNew, iFrom, aCsrMap); + } pNew->pPrior = pPrior; if( pPrior ) pPrior->pNext = pNew; pNew->pNext = p; p->pPrior = pNew; - SELECTTRACE(2,pParse,p,("compound-subquery flattener" + TREETRACE(0x4,pParse,p,("compound-subquery flattener" " creates %u as peer\n",pNew->selId)); } - if( db->mallocFailed ) return 1; + assert( pSubitem->pSelect==0 ); + } + sqlite3DbFree(db, aCsrMap); + if( db->mallocFailed ){ + pSubitem->pSelect = pSub1; + return 1; } - - /* 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 @@ -4005,8 +4578,10 @@ static int flattenSubquery( Table *pTabToDel = pSubitem->pTab; if( pTabToDel->nTabRef==1 ){ Parse *pToplevel = sqlite3ParseToplevel(pParse); - pTabToDel->pNextZombie = pToplevel->pZombieTab; - pToplevel->pZombieTab = pTabToDel; + sqlite3ParserAddCleanup(pToplevel, + (void(*)(sqlite3*,void*))sqlite3DeleteTable, + pTabToDel); + testcase( pToplevel->earlyCleanup ); }else{ pTabToDel->nTabRef--; } @@ -4026,24 +4601,20 @@ static int flattenSubquery( ** those references with expressions that resolve to the subquery FROM ** elements we are now copying in. */ + pSub = pSub1; for(pParent=p; pParent; pParent=pParent->pPrior, pSub=pSub->pPrior){ int nSubSrc; u8 jointype = 0; + u8 ltorj = pSrc->a[iFrom].fg.jointype & JT_LTORJ; assert( pSub!=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 ){ - assert( pParent==p ); /* First time through the loop */ - jointype = pSubitem->fg.jointype; - }else{ - assert( pParent!=p ); /* 2nd and subsequent times through the loop */ - pSrc = sqlite3SrcListAppend(pParse, 0, 0, 0); - if( pSrc==0 ) break; - pParent->pSrc = pSrc; + if( pParent==p ){ + jointype = pSubitem->fg.jointype; /* First time through the loop */ } - + /* 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 @@ -4069,17 +4640,20 @@ static int flattenSubquery( ** outer query. */ for(i=0; i<nSubSrc; i++){ - sqlite3IdListDelete(db, pSrc->a[i+iFrom].pUsing); - assert( pSrc->a[i+iFrom].fg.isTabFunc==0 ); - pSrc->a[i+iFrom] = pSubSrc->a[i]; + SrcItem *pItem = &pSrc->a[i+iFrom]; + if( pItem->fg.isUsing ) sqlite3IdListDelete(db, pItem->u3.pUsing); + assert( pItem->fg.isTabFunc==0 ); + *pItem = pSubSrc->a[i]; + pItem->fg.jointype |= ltorj; iNewParent = pSubSrc->a[i].iCursor; memset(&pSubSrc->a[i], 0, sizeof(pSubSrc->a[i])); } - pSrc->a[iFrom].fg.jointype = jointype; - - /* Now begin substituting subquery result set expressions for + pSrc->a[iFrom].fg.jointype &= JT_LTORJ; + pSrc->a[iFrom].fg.jointype |= jointype | ltorj; + + /* Now begin substituting subquery result set expressions for ** references to the iParent in the outer query. - ** + ** ** Example: ** ** SELECT a+5, b*10 FROM (SELECT x*3 AS a, y+10 AS b FROM t1) WHERE a>b; @@ -4094,7 +4668,7 @@ static int flattenSubquery( ** ORDER BY column expression is identical to the iOrderByCol'th ** expression returned by SELECT statement pSub. Since these values ** do not necessarily correspond to columns in SELECT statement pParent, - ** zero them before transfering the ORDER BY clause. + ** zero them before transferring the ORDER BY clause. ** ** Not doing this may cause an error if a subsequent call to this ** function attempts to flatten a compound sub-query into pParent @@ -4110,8 +4684,8 @@ static int flattenSubquery( } pWhere = pSub->pWhere; pSub->pWhere = 0; - if( isLeftJoin>0 ){ - sqlite3SetJoinExpr(pWhere, iNewParent); + if( isOuterJoin>0 ){ + sqlite3SetJoinExpr(pWhere, iNewParent, EP_OuterON); } if( pWhere ){ if( pParent->pWhere ){ @@ -4125,16 +4699,17 @@ static int flattenSubquery( x.pParse = pParse; x.iTable = iParent; x.iNewTable = iNewParent; - x.isLeftJoin = isLeftJoin; + x.isOuterJoin = isOuterJoin; x.pEList = pSub->pEList; + x.pCList = findLeftmostExprlist(pSub); substSelect(&x, pParent, 0); } - + /* The flattened query is a compound if either the inner or the ** outer query is a compound. */ pParent->selFlags |= pSub->selFlags & SF_Compound; assert( (pSub->selFlags & SF_Distinct)==0 ); /* restriction (17b) */ - + /* ** SELECT ... FROM (SELECT ... LIMIT a OFFSET b) LIMIT x OFFSET y; ** @@ -4146,23 +4721,22 @@ static int flattenSubquery( pSub->pLimit = 0; } - /* Recompute the SrcList_item.colUsed masks for the flattened + /* Recompute the SrcItem.colUsed masks for the flattened ** tables. */ for(i=0; i<nSubSrc; i++){ recomputeColumnsUsed(pParent, &pSrc->a[i+iFrom]); } } - /* Finially, delete what is left of the subquery and return - ** success. + /* Finally, delete what is left of the subquery and return success. */ sqlite3AggInfoPersistWalkerInit(&w, pParse); sqlite3WalkSelect(&w,pSub1); sqlite3SelectDelete(db, pSub1); -#if SELECTTRACE_ENABLED - if( sqlite3SelectTrace & 0x100 ){ - SELECTTRACE(0x100,pParse,p,("After flattening:\n")); +#if TREETRACE_ENABLED + if( sqlite3TreeTrace & 0x4 ){ + TREETRACE(0x4,pParse,p,("After flattening:\n")); sqlite3TreeViewSelect(0, p, 0); } #endif @@ -4178,14 +4752,18 @@ static int flattenSubquery( typedef struct WhereConst WhereConst; struct WhereConst { Parse *pParse; /* Parsing context */ + u8 *pOomFault; /* Pointer to pParse->db->mallocFailed */ int nConst; /* Number for COLUMN=CONSTANT terms */ int nChng; /* Number of times a constant is propagated */ + int bHasAffBlob; /* At least one column in apExpr[] as affinity BLOB */ + u32 mExcludeOn; /* Which ON expressions to exclude from considertion. + ** Either EP_OuterON or EP_InnerON|EP_OuterON */ Expr **apExpr; /* [i*2] is COLUMN and [i*2+1] is VALUE */ }; /* ** Add a new entry to the pConst object. Except, do not add duplicate -** pColumn entires. Also, do not add if doing so would not be appropriate. +** pColumn entries. Also, do not add if doing so would not be appropriate. ** ** The caller guarantees the pColumn is a column and pValue is a constant. ** This routine has to do some additional checks before completing the @@ -4218,6 +4796,9 @@ static void constInsert( return; /* Already present. Return without doing anything. */ } } + if( sqlite3ExprAffinity(pColumn)==SQLITE_AFF_BLOB ){ + pConst->bHasAffBlob = 1; + } pConst->nConst++; pConst->apExpr = sqlite3DbReallocOrFree(pConst->pParse->db, pConst->apExpr, @@ -4238,8 +4819,12 @@ static void constInsert( */ static void findConstInWhere(WhereConst *pConst, Expr *pExpr){ Expr *pRight, *pLeft; - if( pExpr==0 ) return; - if( ExprHasProperty(pExpr, EP_FromJoin) ) return; + if( NEVER(pExpr==0) ) return; + if( ExprHasProperty(pExpr, pConst->mExcludeOn) ){ + testcase( ExprHasProperty(pExpr, EP_OuterON) ); + testcase( ExprHasProperty(pExpr, EP_InnerON) ); + return; + } if( pExpr->op==TK_AND ){ findConstInWhere(pConst, pExpr->pRight); findConstInWhere(pConst, pExpr->pLeft); @@ -4259,38 +4844,85 @@ static void findConstInWhere(WhereConst *pConst, Expr *pExpr){ } /* -** This is a Walker expression callback. pExpr is a candidate expression -** to be replaced by a value. If pExpr is equivalent to one of the -** columns named in pWalker->u.pConst, then overwrite it with its -** corresponding value. +** This is a helper function for Walker callback propagateConstantExprRewrite(). +** +** Argument pExpr is a candidate expression to be replaced by a value. If +** pExpr is equivalent to one of the columns named in pWalker->u.pConst, +** then overwrite it with the corresponding value. Except, do not do so +** if argument bIgnoreAffBlob is non-zero and the affinity of pExpr +** is SQLITE_AFF_BLOB. */ -static int propagateConstantExprRewrite(Walker *pWalker, Expr *pExpr){ +static int propagateConstantExprRewriteOne( + WhereConst *pConst, + Expr *pExpr, + int bIgnoreAffBlob +){ int i; - WhereConst *pConst; + if( pConst->pOomFault[0] ) return WRC_Prune; if( pExpr->op!=TK_COLUMN ) return WRC_Continue; - if( ExprHasProperty(pExpr, EP_FixedCol|EP_FromJoin) ){ + if( ExprHasProperty(pExpr, EP_FixedCol|pConst->mExcludeOn) ){ testcase( ExprHasProperty(pExpr, EP_FixedCol) ); - testcase( ExprHasProperty(pExpr, EP_FromJoin) ); + testcase( ExprHasProperty(pExpr, EP_OuterON) ); + testcase( ExprHasProperty(pExpr, EP_InnerON) ); return WRC_Continue; } - pConst = pWalker->u.pConst; for(i=0; i<pConst->nConst; i++){ Expr *pColumn = pConst->apExpr[i*2]; if( pColumn==pExpr ) continue; if( pColumn->iTable!=pExpr->iTable ) continue; if( pColumn->iColumn!=pExpr->iColumn ) continue; + if( bIgnoreAffBlob && sqlite3ExprAffinity(pColumn)==SQLITE_AFF_BLOB ){ + break; + } /* A match is found. Add the EP_FixedCol property */ pConst->nChng++; ExprClearProperty(pExpr, EP_Leaf); ExprSetProperty(pExpr, EP_FixedCol); assert( pExpr->pLeft==0 ); pExpr->pLeft = sqlite3ExprDup(pConst->pParse->db, pConst->apExpr[i*2+1], 0); + if( pConst->pParse->db->mallocFailed ) return WRC_Prune; break; } return WRC_Prune; } /* +** This is a Walker expression callback. pExpr is a node from the WHERE +** clause of a SELECT statement. This function examines pExpr to see if +** any substitutions based on the contents of pWalker->u.pConst should +** be made to pExpr or its immediate children. +** +** A substitution is made if: +** +** + pExpr is a column with an affinity other than BLOB that matches +** one of the columns in pWalker->u.pConst, or +** +** + pExpr is a binary comparison operator (=, <=, >=, <, >) that +** uses an affinity other than TEXT and one of its immediate +** children is a column that matches one of the columns in +** pWalker->u.pConst. +*/ +static int propagateConstantExprRewrite(Walker *pWalker, Expr *pExpr){ + WhereConst *pConst = pWalker->u.pConst; + assert( TK_GT==TK_EQ+1 ); + assert( TK_LE==TK_EQ+2 ); + assert( TK_LT==TK_EQ+3 ); + assert( TK_GE==TK_EQ+4 ); + if( pConst->bHasAffBlob ){ + if( (pExpr->op>=TK_EQ && pExpr->op<=TK_GE) + || pExpr->op==TK_IS + ){ + propagateConstantExprRewriteOne(pConst, pExpr->pLeft, 0); + if( pConst->pOomFault[0] ) return WRC_Prune; + if( sqlite3ExprAffinity(pExpr->pLeft)!=SQLITE_AFF_TEXT ){ + propagateConstantExprRewriteOne(pConst, pExpr->pRight, 0); + } + } + } + return propagateConstantExprRewriteOne(pConst, pExpr, pConst->bHasAffBlob); +} + +/* ** The WHERE-clause constant propagation optimization. ** ** If the WHERE clause contains terms of the form COLUMN=CONSTANT or @@ -4317,7 +4949,7 @@ static int propagateConstantExprRewrite(Walker *pWalker, Expr *pExpr){ ** SELECT * FROM t1 WHERE a=123 AND b=123; ** ** The two SELECT statements above should return different answers. b=a -** is alway true because the comparison uses numeric affinity, but b=123 +** is always true because the comparison uses numeric affinity, but b=123 ** is false because it uses text affinity and '0123' is not the same as '123'. ** To work around this, the expression tree is not actually changed from ** "b=a" to "b=123" but rather the "a" in "b=a" is tagged with EP_FixedCol @@ -4325,6 +4957,21 @@ static int propagateConstantExprRewrite(Walker *pWalker, Expr *pExpr){ ** routines know to generate the constant "123" instead of looking up the ** column value. Also, to avoid collation problems, this optimization is ** only attempted if the "a=123" term uses the default BINARY collation. +** +** 2021-05-25 forum post 6a06202608: Another troublesome case is... +** +** CREATE TABLE t1(x); +** INSERT INTO t1 VALUES(10.0); +** SELECT 1 FROM t1 WHERE x=10 AND x LIKE 10; +** +** The query should return no rows, because the t1.x value is '10.0' not '10' +** and '10.0' is not LIKE '10'. But if we are not careful, the first WHERE +** term "x=10" will cause the second WHERE term to become "10 LIKE 10", +** resulting in a false positive. To avoid this, constant propagation for +** columns with BLOB affinity is only allowed if the constant is used with +** operators ==, <=, <, >=, >, or IS in a way that will cause the correct +** type conversions to occur. See logic associated with the bHasAffBlob flag +** for details. */ static int propagateConstants( Parse *pParse, /* The parsing context */ @@ -4334,10 +4981,23 @@ static int propagateConstants( Walker w; int nChng = 0; x.pParse = pParse; + x.pOomFault = &pParse->db->mallocFailed; do{ x.nConst = 0; x.nChng = 0; x.apExpr = 0; + x.bHasAffBlob = 0; + if( ALWAYS(p->pSrc!=0) + && p->pSrc->nSrc>0 + && (p->pSrc->a[0].fg.jointype & JT_LTORJ)!=0 + ){ + /* Do not propagate constants on any ON clause if there is a + ** RIGHT JOIN anywhere in the query */ + x.mExcludeOn = EP_InnerON | EP_OuterON; + }else{ + /* Do not propagate constants through the ON clause of a LEFT JOIN */ + x.mExcludeOn = EP_OuterON; + } findConstInWhere(&x, p->pWhere); if( x.nConst ){ memset(&w, 0, sizeof(w)); @@ -4351,11 +5011,40 @@ static int propagateConstants( sqlite3DbFree(x.pParse->db, x.apExpr); nChng += x.nChng; } - }while( x.nChng ); + }while( x.nChng ); return nChng; } #if !defined(SQLITE_OMIT_SUBQUERY) || !defined(SQLITE_OMIT_VIEW) +# if !defined(SQLITE_OMIT_WINDOWFUNC) +/* +** This function is called to determine whether or not it is safe to +** push WHERE clause expression pExpr down to FROM clause sub-query +** pSubq, which contains at least one window function. Return 1 +** if it is safe and the expression should be pushed down, or 0 +** otherwise. +** +** It is only safe to push the expression down if it consists only +** of constants and copies of expressions that appear in the PARTITION +** BY clause of all window function used by the sub-query. It is safe +** to filter out entire partitions, but not rows within partitions, as +** this may change the results of the window functions. +** +** At the time this function is called it is guaranteed that +** +** * the sub-query uses only one distinct window frame, and +** * that the window frame has a PARTITION BY clause. +*/ +static int pushDownWindowCheck(Parse *pParse, Select *pSubq, Expr *pExpr){ + assert( pSubq->pWin->pPartition ); + assert( (pSubq->selFlags & SF_MultiPart)==0 ); + assert( pSubq->pPrior==0 ); + return sqlite3ExprIsConstantOrGroupBy(pParse, pExpr, pSubq->pWin->pPartition); +} +# endif /* SQLITE_OMIT_WINDOWFUNC */ +#endif /* !defined(SQLITE_OMIT_SUBQUERY) || !defined(SQLITE_OMIT_VIEW) */ + +#if !defined(SQLITE_OMIT_SUBQUERY) || !defined(SQLITE_OMIT_VIEW) /* ** Make copies of relevant WHERE clause terms of the outer query into ** the WHERE clause of subquery. Example: @@ -4402,9 +5091,47 @@ static int propagateConstants( ** But if the (b2=2) term were to be pushed down into the bb subquery, ** then the (1,1,NULL) row would be suppressed. ** -** (6) The inner query features one or more window-functions (since -** changes to the WHERE clause of the inner query could change the -** window over which window functions are calculated). +** (6) Window functions make things tricky as changes to the WHERE clause +** of the inner query could change the window over which window +** functions are calculated. Therefore, do not attempt the optimization +** if: +** +** (6a) The inner query uses multiple incompatible window partitions. +** +** (6b) The inner query is a compound and uses window-functions. +** +** (6c) The WHERE clause does not consist entirely of constants and +** copies of expressions found in the PARTITION BY clause of +** all window-functions used by the sub-query. It is safe to +** filter out entire partitions, as this does not change the +** window over which any window-function is calculated. +** +** (7) The inner query is a Common Table Expression (CTE) that should +** be materialized. (This restriction is implemented in the calling +** routine.) +** +** (8) If the subquery is a compound that uses UNION, INTERSECT, +** or EXCEPT, then all of the result set columns for all arms of +** the compound must use the BINARY collating sequence. +** +** (9) All three of the following are true: +** +** (9a) The WHERE clause expression originates in the ON or USING clause +** of a join (either an INNER or an OUTER join), and +** +** (9b) The subquery is to the right of the ON/USING clause +** +** (9c) There is a RIGHT JOIN (or FULL JOIN) in between the ON/USING +** clause and the subquery. +** +** Without this restriction, the push-down optimization might move +** the ON/USING filter expression from the left side of a RIGHT JOIN +** over to the right side, which leads to incorrect answers. See +** also restriction (6) in sqlite3ExprIsSingleTableConstraint(). +** +** (10) The inner query is not the right-hand table of a RIGHT JOIN. +** +** (11) The subquery is not a VALUES clause ** ** Return 0 if no changes are made and non-zero if one or more WHERE clause ** terms are duplicated into the subquery. @@ -4413,20 +5140,56 @@ static int pushDownWhereTerms( Parse *pParse, /* Parse context (for malloc() and error reporting) */ Select *pSubq, /* The subquery whose WHERE clause is to be augmented */ Expr *pWhere, /* The WHERE clause of the outer query */ - int iCursor, /* Cursor number of the subquery */ - int isLeftJoin /* True if pSubq is the right term of a LEFT JOIN */ + SrcList *pSrcList, /* The complete from clause of the outer query */ + int iSrc /* Which FROM clause term to try to push into */ ){ Expr *pNew; + SrcItem *pSrc; /* The subquery FROM term into which WHERE is pushed */ int nChng = 0; - Select *pSel; + pSrc = &pSrcList->a[iSrc]; if( pWhere==0 ) return 0; - if( pSubq->selFlags & SF_Recursive ) return 0; /* restriction (2) */ + if( pSubq->selFlags & (SF_Recursive|SF_MultiPart) ){ + return 0; /* restrictions (2) and (11) */ + } + if( pSrc->fg.jointype & (JT_LTORJ|JT_RIGHT) ){ + return 0; /* restrictions (10) */ + } + if( pSubq->pPrior ){ + Select *pSel; + int notUnionAll = 0; + for(pSel=pSubq; pSel; pSel=pSel->pPrior){ + u8 op = pSel->op; + assert( op==TK_ALL || op==TK_SELECT + || op==TK_UNION || op==TK_INTERSECT || op==TK_EXCEPT ); + if( op!=TK_ALL && op!=TK_SELECT ){ + notUnionAll = 1; + } #ifndef SQLITE_OMIT_WINDOWFUNC - for(pSel=pSubq; pSel; pSel=pSel->pPrior){ - if( pSel->pWin ) return 0; /* restriction (6) */ - } + if( pSel->pWin ) return 0; /* restriction (6b) */ +#endif + } + if( notUnionAll ){ + /* If any of the compound arms are connected using UNION, INTERSECT, + ** or EXCEPT, then we must ensure that none of the columns use a + ** non-BINARY collating sequence. */ + for(pSel=pSubq; pSel; pSel=pSel->pPrior){ + int ii; + const ExprList *pList = pSel->pEList; + assert( pList!=0 ); + for(ii=0; ii<pList->nExpr; ii++){ + CollSeq *pColl = sqlite3ExprCollSeq(pParse, pList->a[ii].pExpr); + if( !sqlite3IsBinary(pColl) ){ + return 0; /* Restriction (8) */ + } + } + } + } + }else{ +#ifndef SQLITE_OMIT_WINDOWFUNC + if( pSubq->pWin && pSubq->pWin->pPartition==0 ) return 0; #endif + } #ifdef SQLITE_DEBUG /* Only the first term of a compound can have a WITH clause. But make @@ -4434,7 +5197,7 @@ static int pushDownWhereTerms( ** in the future. */ { - Select *pX; + Select *pX; for(pX=pSubq; pX; pX=pX->pPrior){ assert( (pX->selFlags & (SF_Recursive))==0 ); } @@ -4445,31 +5208,63 @@ static int pushDownWhereTerms( return 0; /* restriction (3) */ } while( pWhere->op==TK_AND ){ - nChng += pushDownWhereTerms(pParse, pSubq, pWhere->pRight, - iCursor, isLeftJoin); + nChng += pushDownWhereTerms(pParse, pSubq, pWhere->pRight, pSrcList, iSrc); pWhere = pWhere->pLeft; } + +#if 0 /* These checks now done by sqlite3ExprIsSingleTableConstraint() */ + if( ExprHasProperty(pWhere, EP_OuterON|EP_InnerON) /* (9a) */ + && (pSrcList->a[0].fg.jointype & JT_LTORJ)!=0 /* Fast pre-test of (9c) */ + ){ + int jj; + for(jj=0; jj<iSrc; jj++){ + if( pWhere->w.iJoin==pSrcList->a[jj].iCursor ){ + /* If we reach this point, both (9a) and (9b) are satisfied. + ** The following loop checks (9c): + */ + for(jj++; jj<iSrc; jj++){ + if( (pSrcList->a[jj].fg.jointype & JT_RIGHT)!=0 ){ + return 0; /* restriction (9) */ + } + } + } + } + } if( isLeftJoin - && (ExprHasProperty(pWhere,EP_FromJoin)==0 - || pWhere->iRightJoinTable!=iCursor) + && (ExprHasProperty(pWhere,EP_OuterON)==0 + || pWhere->w.iJoin!=iCursor) ){ return 0; /* restriction (4) */ } - if( ExprHasProperty(pWhere,EP_FromJoin) && pWhere->iRightJoinTable!=iCursor ){ + if( ExprHasProperty(pWhere,EP_OuterON) + && pWhere->w.iJoin!=iCursor + ){ return 0; /* restriction (5) */ } - if( sqlite3ExprIsTableConstant(pWhere, iCursor) ){ +#endif + + if( sqlite3ExprIsSingleTableConstraint(pWhere, pSrcList, iSrc) ){ nChng++; + pSubq->selFlags |= SF_PushDown; while( pSubq ){ SubstContext x; pNew = sqlite3ExprDup(pParse->db, pWhere, 0); - unsetJoinExpr(pNew, -1); + unsetJoinExpr(pNew, -1, 1); x.pParse = pParse; - x.iTable = iCursor; - x.iNewTable = iCursor; - x.isLeftJoin = 0; + x.iTable = pSrc->iCursor; + x.iNewTable = pSrc->iCursor; + x.isOuterJoin = 0; x.pEList = pSubq->pEList; + x.pCList = findLeftmostExprlist(pSubq); pNew = substExpr(&x, pNew); +#ifndef SQLITE_OMIT_WINDOWFUNC + if( pSubq->pWin && 0==pushDownWindowCheck(pParse, pSubq, pNew) ){ + /* Restriction 6c has prevented push-down in this case */ + sqlite3ExprDelete(pParse->db, pNew); + nChng--; + break; + } +#endif if( pSubq->selFlags & SF_Aggregate ){ pSubq->pHaving = sqlite3ExprAnd(pParse, pSubq->pHaving, pNew); }else{ @@ -4483,8 +5278,80 @@ static int pushDownWhereTerms( #endif /* !defined(SQLITE_OMIT_SUBQUERY) || !defined(SQLITE_OMIT_VIEW) */ /* +** Check to see if a subquery contains result-set columns that are +** never used. If it does, change the value of those result-set columns +** to NULL so that they do not cause unnecessary work to compute. +** +** Return the number of column that were changed to NULL. +*/ +static int disableUnusedSubqueryResultColumns(SrcItem *pItem){ + int nCol; + Select *pSub; /* The subquery to be simplified */ + Select *pX; /* For looping over compound elements of pSub */ + Table *pTab; /* The table that describes the subquery */ + int j; /* Column number */ + int nChng = 0; /* Number of columns converted to NULL */ + Bitmask colUsed; /* Columns that may not be NULLed out */ + + assert( pItem!=0 ); + if( pItem->fg.isCorrelated || pItem->fg.isCte ){ + return 0; + } + assert( pItem->pTab!=0 ); + pTab = pItem->pTab; + assert( pItem->pSelect!=0 ); + pSub = pItem->pSelect; + assert( pSub->pEList->nExpr==pTab->nCol ); + for(pX=pSub; pX; pX=pX->pPrior){ + if( (pX->selFlags & (SF_Distinct|SF_Aggregate))!=0 ){ + testcase( pX->selFlags & SF_Distinct ); + testcase( pX->selFlags & SF_Aggregate ); + return 0; + } + if( pX->pPrior && pX->op!=TK_ALL ){ + /* This optimization does not work for compound subqueries that + ** use UNION, INTERSECT, or EXCEPT. Only UNION ALL is allowed. */ + return 0; + } +#ifndef SQLITE_OMIT_WINDOWFUNC + if( pX->pWin ){ + /* This optimization does not work for subqueries that use window + ** functions. */ + return 0; + } +#endif + } + colUsed = pItem->colUsed; + if( pSub->pOrderBy ){ + ExprList *pList = pSub->pOrderBy; + for(j=0; j<pList->nExpr; j++){ + u16 iCol = pList->a[j].u.x.iOrderByCol; + if( iCol>0 ){ + iCol--; + colUsed |= ((Bitmask)1)<<(iCol>=BMS ? BMS-1 : iCol); + } + } + } + nCol = pTab->nCol; + for(j=0; j<nCol; j++){ + Bitmask m = j<BMS-1 ? MASKBIT(j) : TOPBIT; + if( (m & colUsed)!=0 ) continue; + for(pX=pSub; pX; pX=pX->pPrior) { + Expr *pY = pX->pEList->a[j].pExpr; + if( pY->op==TK_NULL ) continue; + pY->op = TK_NULL; + ExprClearProperty(pY, EP_Skip|EP_Unlikely); + pX->selFlags |= SF_PushDown; + nChng++; + } + } + return nChng; +} + + +/* ** The pFunc is the only aggregate function in the query. Check to see -** if the query is a candidate for the min/max optimization. +** if the query is a candidate for the min/max optimization. ** ** If the query is a candidate for the min/max optimization, then set ** *ppMinMax to be an ORDER BY clause to be used for the optimization @@ -4500,7 +5367,7 @@ static int pushDownWhereTerms( */ static u8 minMaxQuery(sqlite3 *db, Expr *pFunc, ExprList **ppMinMax){ int eRet = WHERE_ORDERBY_NORMAL; /* Return value */ - ExprList *pEList = pFunc->x.pList; /* Arguments to agg function */ + ExprList *pEList; /* Arguments to agg function */ const char *zFunc; /* Name of aggregate function pFunc */ ExprList *pOrderBy; u8 sortFlags = 0; @@ -4508,9 +5375,16 @@ static u8 minMaxQuery(sqlite3 *db, Expr *pFunc, ExprList **ppMinMax){ assert( *ppMinMax==0 ); assert( pFunc->op==TK_AGG_FUNCTION ); assert( !IsWindowFunc(pFunc) ); - if( pEList==0 || pEList->nExpr!=1 || ExprHasProperty(pFunc, EP_WinFunc) ){ + assert( ExprUseXList(pFunc) ); + pEList = pFunc->x.pList; + if( pEList==0 + || pEList->nExpr!=1 + || ExprHasProperty(pFunc, EP_WinFunc) + || OptimizationDisabled(db, SQLITE_MinMaxOpt) + ){ return eRet; } + assert( !ExprHasProperty(pFunc, EP_IntValue) ); zFunc = pFunc->u.zToken; if( sqlite3StrICmp(zFunc, "min")==0 ){ eRet = WHERE_ORDERBY_MIN; @@ -4525,20 +5399,26 @@ static u8 minMaxQuery(sqlite3 *db, Expr *pFunc, ExprList **ppMinMax){ } *ppMinMax = pOrderBy = sqlite3ExprListDup(db, pEList, 0); assert( pOrderBy!=0 || db->mallocFailed ); - if( pOrderBy ) pOrderBy->a[0].sortFlags = sortFlags; + if( pOrderBy ) pOrderBy->a[0].fg.sortFlags = sortFlags; return eRet; } /* ** The select statement passed as the first argument is an aggregate query. -** The second argument is the associated aggregate-info object. This +** The second argument 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. +** <tbl> is returned. Otherwise, NULL is returned. +** +** This routine checks to see if it is safe to use the count optimization. +** A correct answer is still obtained (though perhaps more slowly) if +** this routine returns NULL when it could have returned a table pointer. +** But returning the pointer when NULL should have been returned can +** result in incorrect answers and/or crashes. So, when in doubt, return NULL. */ static Table *isSimpleCount(Select *p, AggInfo *pAggInfo){ Table *pTab; @@ -4546,19 +5426,27 @@ static Table *isSimpleCount(Select *p, AggInfo *pAggInfo){ assert( !p->pGroupBy ); - if( p->pWhere || p->pEList->nExpr!=1 - || p->pSrc->nSrc!=1 || p->pSrc->a[0].pSelect + if( p->pWhere + || p->pEList->nExpr!=1 + || p->pSrc->nSrc!=1 + || p->pSrc->a[0].pSelect + || pAggInfo->nFunc!=1 + || p->pHaving ){ return 0; } pTab = p->pSrc->a[0].pTab; + assert( pTab!=0 ); + assert( !IsView(pTab) ); + if( !IsOrdinaryTable(pTab) ) return 0; pExpr = p->pEList->a[0].pExpr; - assert( pTab && !pTab->pSelect && pExpr ); - - if( IsVirtual(pTab) ) return 0; + assert( pExpr!=0 ); if( pExpr->op!=TK_AGG_FUNCTION ) return 0; - if( NEVER(pAggInfo->nFunc==0) ) return 0; + if( pExpr->pAggInfo!=pAggInfo ) return 0; if( (pAggInfo->aFunc[0].pFunc->funcFlags&SQLITE_FUNC_COUNT)==0 ) return 0; + assert( pAggInfo->aFunc[0].pFExpr==pExpr ); + testcase( ExprHasProperty(pExpr, EP_Distinct) ); + testcase( ExprHasProperty(pExpr, EP_WinFunc) ); if( ExprHasProperty(pExpr, EP_Distinct|EP_WinFunc) ) return 0; return pTab; @@ -4567,30 +5455,33 @@ static Table *isSimpleCount(Select *p, AggInfo *pAggInfo){ /* ** 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 +** 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->fg.isIndexedBy ){ - Table *pTab = pFrom->pTab; - char *zIndexedBy = pFrom->u1.zIndexedBy; - Index *pIdx; - for(pIdx=pTab->pIndex; - pIdx && sqlite3StrICmp(pIdx->zName, zIndexedBy); - pIdx=pIdx->pNext - ); - if( !pIdx ){ - sqlite3ErrorMsg(pParse, "no such index: %s", zIndexedBy, 0); - pParse->checkSchema = 1; - return SQLITE_ERROR; - } - pFrom->pIBIndex = pIdx; +int sqlite3IndexedByLookup(Parse *pParse, SrcItem *pFrom){ + Table *pTab = pFrom->pTab; + char *zIndexedBy = pFrom->u1.zIndexedBy; + Index *pIdx; + assert( pTab!=0 ); + assert( pFrom->fg.isIndexedBy!=0 ); + + for(pIdx=pTab->pIndex; + pIdx && sqlite3StrICmp(pIdx->zName, zIndexedBy); + pIdx=pIdx->pNext + ); + if( !pIdx ){ + sqlite3ErrorMsg(pParse, "no such index: %s", zIndexedBy, 0); + pParse->checkSchema = 1; + return SQLITE_ERROR; } + assert( pFrom->fg.isCte==0 ); + pFrom->u2.pIBIndex = pIdx; return SQLITE_OK; } + /* -** Detect compound SELECT statements that use an ORDER BY clause with +** Detect compound SELECT statements that use an ORDER BY clause with ** an alternative collating sequence. ** ** SELECT ... FROM t1 EXCEPT SELECT ... FROM t2 ORDER BY .. COLLATE ... @@ -4645,7 +5536,7 @@ static int convertCompoundSelectToSubquery(Walker *pWalker, Select *p){ pNew = sqlite3DbMallocZero(db, sizeof(*pNew) ); if( pNew==0 ) return WRC_Abort; memset(&dummy, 0, sizeof(dummy)); - pNewSrc = sqlite3SrcListAppendFromTerm(pParse,0,0,0,&dummy,pNew,0,0); + pNewSrc = sqlite3SrcListAppendFromTerm(pParse,0,0,0,&dummy,pNew,0); if( pNewSrc==0 ) return WRC_Abort; *pNew = *p; p->pSrc = pNewSrc; @@ -4675,7 +5566,7 @@ static int convertCompoundSelectToSubquery(Walker *pWalker, Select *p){ ** arguments. If it does, leave an error message in pParse and return ** non-zero, since pFrom is not allowed to be a table-valued function. */ -static int cannotBeFunction(Parse *pParse, struct SrcList_item *pFrom){ +static int cannotBeFunction(Parse *pParse, SrcItem *pFrom){ if( pFrom->fg.isTabFunc ){ sqlite3ErrorMsg(pParse, "'%s' is not a function", pFrom->zName); return 1; @@ -4685,9 +5576,9 @@ static int cannotBeFunction(Parse *pParse, struct SrcList_item *pFrom){ #ifndef SQLITE_OMIT_CTE /* -** Argument pWith (which may be NULL) points to a linked list of nested -** WITH contexts, from inner to outermost. If the table identified by -** FROM clause element pItem is really a common-table-expression (CTE) +** Argument pWith (which may be NULL) points to a linked list of nested +** WITH contexts, from inner to outermost. If the table identified by +** FROM clause element pItem is really a common-table-expression (CTE) ** then return a pointer to the CTE definition for that table. Otherwise ** return NULL. ** @@ -4696,21 +5587,22 @@ static int cannotBeFunction(Parse *pParse, struct SrcList_item *pFrom){ */ static struct Cte *searchWith( With *pWith, /* Current innermost WITH clause */ - struct SrcList_item *pItem, /* FROM clause element to resolve */ + SrcItem *pItem, /* FROM clause element to resolve */ With **ppContext /* OUT: WITH clause return value belongs to */ ){ - const char *zName; - if( pItem->zDatabase==0 && (zName = pItem->zName)!=0 ){ - With *p; - for(p=pWith; p; p=p->pOuter){ - int i; - for(i=0; i<p->nCte; i++){ - if( sqlite3StrICmp(zName, p->a[i].zName)==0 ){ - *ppContext = p; - return &p->a[i]; - } + const char *zName = pItem->zName; + With *p; + assert( pItem->zDatabase==0 ); + assert( zName!=0 ); + for(p=pWith; p; p=p->pOuter){ + int i; + for(i=0; i<p->nCte; i++){ + if( sqlite3StrICmp(zName, p->a[i].zName)==0 ){ + *ppContext = p; + return &p->a[i]; } } + if( p->bView ) break; } return 0; } @@ -4720,58 +5612,92 @@ static struct Cte *searchWith( ** ** This routine pushes the WITH clause passed as the second argument ** onto the top of the stack. If argument bFree is true, then this -** WITH clause will never be popped from the stack. In this case it -** should be freed along with the Parse object. In other cases, when -** bFree==0, the With object will be freed along with the SELECT +** WITH clause will never be popped from the stack but should instead +** be freed along with the Parse object. In other cases, when +** bFree==0, the With object will be freed along with the SELECT ** statement with which it is associated. +** +** This routine returns a copy of pWith. Or, if bFree is true and +** the pWith object is destroyed immediately due to an OOM condition, +** then this routine return NULL. +** +** If bFree is true, do not continue to use the pWith pointer after +** calling this routine, Instead, use only the return value. */ -void sqlite3WithPush(Parse *pParse, With *pWith, u8 bFree){ - assert( bFree==0 || (pParse->pWith==0 && pParse->pWithToFree==0) ); +With *sqlite3WithPush(Parse *pParse, With *pWith, u8 bFree){ if( pWith ){ - assert( pParse->pWith!=pWith ); - pWith->pOuter = pParse->pWith; - pParse->pWith = pWith; - if( bFree ) pParse->pWithToFree = pWith; + if( bFree ){ + pWith = (With*)sqlite3ParserAddCleanup(pParse, + (void(*)(sqlite3*,void*))sqlite3WithDelete, + pWith); + if( pWith==0 ) return 0; + } + if( pParse->nErr==0 ){ + assert( pParse->pWith!=pWith ); + pWith->pOuter = pParse->pWith; + pParse->pWith = pWith; + } } + return pWith; } /* -** This function checks if argument pFrom refers to a CTE declared by -** a WITH clause on the stack currently maintained by the parser. And, -** if currently processing a CTE expression, if it is a recursive -** reference to the current CTE. -** -** If pFrom falls into either of the two categories above, pFrom->pTab -** and other fields are populated accordingly. The caller should check -** (pFrom->pTab!=0) to determine whether or not a successful match -** was found. -** -** Whether or not a match is found, SQLITE_OK is returned if no error -** occurs. If an error does occur, an error message is stored in the -** parser and some error code other than SQLITE_OK returned. +** This function checks if argument pFrom refers to a CTE declared by +** a WITH clause on the stack currently maintained by the parser (on the +** pParse->pWith linked list). And if currently processing a CTE +** CTE expression, through routine checks to see if the reference is +** a recursive reference to the CTE. +** +** If pFrom matches a CTE according to either of these two above, pFrom->pTab +** and other fields are populated accordingly. +** +** Return 0 if no match is found. +** Return 1 if a match is found. +** Return 2 if an error condition is detected. */ -static int withExpand( - Walker *pWalker, - struct SrcList_item *pFrom +static int resolveFromTermToCte( + Parse *pParse, /* The parsing context */ + Walker *pWalker, /* Current tree walker */ + SrcItem *pFrom /* The FROM clause term to check */ ){ - Parse *pParse = pWalker->pParse; - sqlite3 *db = pParse->db; - struct Cte *pCte; /* Matched CTE (or NULL if no match) */ - With *pWith; /* WITH clause that pCte belongs to */ + Cte *pCte; /* Matched CTE (or NULL if no match) */ + With *pWith; /* The matching WITH */ assert( pFrom->pTab==0 ); + if( pParse->pWith==0 ){ + /* There are no WITH clauses in the stack. No match is possible */ + return 0; + } if( pParse->nErr ){ - return SQLITE_ERROR; + /* Prior errors might have left pParse->pWith in a goofy state, so + ** go no further. */ + return 0; + } + if( pFrom->zDatabase!=0 ){ + /* The FROM term contains a schema qualifier (ex: main.t1) and so + ** it cannot possibly be a CTE reference. */ + return 0; + } + if( pFrom->fg.notCte ){ + /* The FROM term is specifically excluded from matching a CTE. + ** (1) It is part of a trigger that used to have zDatabase but had + ** zDatabase removed by sqlite3FixTriggerStep(). + ** (2) This is the first term in the FROM clause of an UPDATE. + */ + return 0; } - pCte = searchWith(pParse->pWith, pFrom, &pWith); if( pCte ){ + sqlite3 *db = pParse->db; Table *pTab; ExprList *pEList; Select *pSel; Select *pLeft; /* Left-most SELECT statement */ + Select *pRecTerm; /* Left-most recursive term */ int bMayRecursive; /* True if compound joined by UNION [ALL] */ With *pSavedWith; /* Initial value of pParse->pWith */ + int iRecTab = -1; /* Cursor for recursive table */ + CteUse *pCteUse; /* If pCte->zCteErr is non-NULL at this point, then this is an illegal ** recursive reference to CTE pCte. Leave an error in pParse and return @@ -4779,63 +5705,95 @@ static int withExpand( ** In this case, proceed. */ if( pCte->zCteErr ){ sqlite3ErrorMsg(pParse, pCte->zCteErr, pCte->zName); - return SQLITE_ERROR; + return 2; } - if( cannotBeFunction(pParse, pFrom) ) return SQLITE_ERROR; + if( cannotBeFunction(pParse, pFrom) ) return 2; assert( pFrom->pTab==0 ); - pFrom->pTab = pTab = sqlite3DbMallocZero(db, sizeof(Table)); - if( pTab==0 ) return WRC_Abort; + pTab = sqlite3DbMallocZero(db, sizeof(Table)); + if( pTab==0 ) return 2; + pCteUse = pCte->pUse; + if( pCteUse==0 ){ + pCte->pUse = pCteUse = sqlite3DbMallocZero(db, sizeof(pCteUse[0])); + if( pCteUse==0 + || sqlite3ParserAddCleanup(pParse,sqlite3DbFree,pCteUse)==0 + ){ + sqlite3DbFree(db, pTab); + return 2; + } + pCteUse->eM10d = pCte->eM10d; + } + pFrom->pTab = pTab; pTab->nTabRef = 1; pTab->zName = sqlite3DbStrDup(db, pCte->zName); pTab->iPKey = -1; pTab->nRowLogEst = 200; assert( 200==sqlite3LogEst(1048576) ); pTab->tabFlags |= TF_Ephemeral | TF_NoVisibleRowid; pFrom->pSelect = sqlite3SelectDup(db, pCte->pSelect, 0); - if( db->mallocFailed ) return SQLITE_NOMEM_BKPT; + if( db->mallocFailed ) return 2; + pFrom->pSelect->selFlags |= SF_CopyCte; assert( pFrom->pSelect ); + if( pFrom->fg.isIndexedBy ){ + sqlite3ErrorMsg(pParse, "no such index: \"%s\"", pFrom->u1.zIndexedBy); + return 2; + } + pFrom->fg.isCte = 1; + pFrom->u2.pCteUse = pCteUse; + pCteUse->nUse++; /* Check if this is a recursive CTE. */ - pSel = pFrom->pSelect; + pRecTerm = pSel = pFrom->pSelect; bMayRecursive = ( pSel->op==TK_ALL || pSel->op==TK_UNION ); - if( bMayRecursive ){ + while( bMayRecursive && pRecTerm->op==pSel->op ){ int i; - SrcList *pSrc = pFrom->pSelect->pSrc; + SrcList *pSrc = pRecTerm->pSrc; + assert( pRecTerm->pPrior!=0 ); for(i=0; i<pSrc->nSrc; i++){ - struct SrcList_item *pItem = &pSrc->a[i]; - if( pItem->zDatabase==0 - && pItem->zName!=0 + SrcItem *pItem = &pSrc->a[i]; + if( pItem->zDatabase==0 + && pItem->zName!=0 && 0==sqlite3StrICmp(pItem->zName, pCte->zName) - ){ + ){ pItem->pTab = pTab; - pItem->fg.isRecursive = 1; pTab->nTabRef++; - pSel->selFlags |= SF_Recursive; + pItem->fg.isRecursive = 1; + if( pRecTerm->selFlags & SF_Recursive ){ + sqlite3ErrorMsg(pParse, + "multiple references to recursive table: %s", pCte->zName + ); + return 2; + } + pRecTerm->selFlags |= SF_Recursive; + if( iRecTab<0 ) iRecTab = pParse->nTab++; + pItem->iCursor = iRecTab; } } + if( (pRecTerm->selFlags & SF_Recursive)==0 ) break; + pRecTerm = pRecTerm->pPrior; } - /* Only one recursive reference is permitted. */ - if( pTab->nTabRef>2 ){ - sqlite3ErrorMsg( - pParse, "multiple references to recursive table: %s", pCte->zName - ); - return SQLITE_ERROR; - } - assert( pTab->nTabRef==1 || - ((pSel->selFlags&SF_Recursive) && pTab->nTabRef==2 )); - pCte->zCteErr = "circular reference: %s"; pSavedWith = pParse->pWith; pParse->pWith = pWith; - if( bMayRecursive ){ - Select *pPrior = pSel->pPrior; - assert( pPrior->pWith==0 ); - pPrior->pWith = pSel->pWith; - sqlite3WalkSelect(pWalker, pPrior); - pPrior->pWith = 0; + if( pSel->selFlags & SF_Recursive ){ + int rc; + assert( pRecTerm!=0 ); + assert( (pRecTerm->selFlags & SF_Recursive)==0 ); + assert( pRecTerm->pNext!=0 ); + assert( (pRecTerm->pNext->selFlags & SF_Recursive)!=0 ); + assert( pRecTerm->pWith==0 ); + pRecTerm->pWith = pSel->pWith; + rc = sqlite3WalkSelect(pWalker, pRecTerm); + pRecTerm->pWith = 0; + if( rc ){ + pParse->pWith = pSavedWith; + return 2; + } }else{ - sqlite3WalkSelect(pWalker, pSel); + if( sqlite3WalkSelect(pWalker, pSel) ){ + pParse->pWith = pSavedWith; + return 2; + } } pParse->pWith = pWith; @@ -4847,7 +5805,7 @@ static int withExpand( pCte->zName, pEList->nExpr, pCte->pCols->nExpr ); pParse->pWith = pSavedWith; - return SQLITE_ERROR; + return 2; } pEList = pCte->pCols; } @@ -4863,22 +5821,22 @@ static int withExpand( } pCte->zCteErr = 0; pParse->pWith = pSavedWith; + return 1; /* Success */ } - - return SQLITE_OK; + return 0; /* No match */ } #endif #ifndef SQLITE_OMIT_CTE /* -** If the SELECT passed as the second argument has an associated WITH +** If the SELECT passed as the second argument has an associated WITH ** clause, pop it from the stack stored as part of the Parse object. ** ** This function is used as the xSelectCallback2() callback by ** sqlite3SelectExpand() when walking a SELECT tree to resolve table -** names and other FROM clause elements. +** names and other FROM clause elements. */ -static void selectPopWith(Walker *pWalker, Select *p){ +void sqlite3SelectPopWith(Walker *pWalker, Select *p){ Parse *pParse = pWalker->pParse; if( OK_IF_ALWAYS_TRUE(pParse->pWith) && p->pPrior==0 ){ With *pWith = findRightmost(p)->pWith; @@ -4888,18 +5846,16 @@ static void selectPopWith(Walker *pWalker, Select *p){ } } } -#else -#define selectPopWith 0 #endif /* -** The SrcList_item structure passed as the second argument represents a +** The SrcItem structure passed as the second argument represents a ** sub-query in the FROM clause of a SELECT statement. This function -** allocates and populates the SrcList_item.pTab object. If successful, +** allocates and populates the SrcItem.pTab object. If successful, ** SQLITE_OK is returned. Otherwise, if an OOM error is encountered, ** SQLITE_NOMEM. */ -int sqlite3ExpandSubquery(Parse *pParse, struct SrcList_item *pFrom){ +int sqlite3ExpandSubquery(Parse *pParse, SrcItem *pFrom){ Select *pSel = pFrom->pSelect; Table *pTab; @@ -4910,17 +5866,47 @@ int sqlite3ExpandSubquery(Parse *pParse, struct SrcList_item *pFrom){ if( pFrom->zAlias ){ pTab->zName = sqlite3DbStrDup(pParse->db, pFrom->zAlias); }else{ - pTab->zName = sqlite3MPrintf(pParse->db, "subquery_%u", pSel->selId); + pTab->zName = sqlite3MPrintf(pParse->db, "%!S", pFrom); } while( pSel->pPrior ){ pSel = pSel->pPrior; } sqlite3ColumnsFromExprList(pParse, pSel->pEList,&pTab->nCol,&pTab->aCol); pTab->iPKey = -1; pTab->nRowLogEst = 200; assert( 200==sqlite3LogEst(1048576) ); - pTab->tabFlags |= TF_Ephemeral; - +#ifndef SQLITE_ALLOW_ROWID_IN_VIEW + /* The usual case - do not allow ROWID on a subquery */ + pTab->tabFlags |= TF_Ephemeral | TF_NoVisibleRowid; +#else + pTab->tabFlags |= TF_Ephemeral; /* Legacy compatibility mode */ +#endif return pParse->nErr ? SQLITE_ERROR : SQLITE_OK; } + +/* +** Check the N SrcItem objects to the right of pBase. (N might be zero!) +** If any of those SrcItem objects have a USING clause containing zName +** then return true. +** +** If N is zero, or none of the N SrcItem objects to the right of pBase +** contains a USING clause, or if none of the USING clauses contain zName, +** then return false. +*/ +static int inAnyUsingClause( + const char *zName, /* Name we are looking for */ + SrcItem *pBase, /* The base SrcItem. Looking at pBase[1] and following */ + int N /* How many SrcItems to check */ +){ + while( N>0 ){ + N--; + pBase++; + if( pBase->fg.isUsing==0 ) continue; + if( NEVER(pBase->u3.pUsing==0) ) continue; + if( sqlite3IdListIndex(pBase->u3.pUsing, zName)>=0 ) return 1; + } + return 0; +} + + /* ** This routine is a Walker callback for "expanding" a SELECT statement. ** "Expanding" means to do the following: @@ -4928,7 +5914,7 @@ int sqlite3ExpandSubquery(Parse *pParse, struct SrcList_item *pFrom){ ** (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 +** (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 @@ -4947,10 +5933,10 @@ int sqlite3ExpandSubquery(Parse *pParse, struct SrcList_item *pFrom){ */ static int selectExpander(Walker *pWalker, Select *p){ Parse *pParse = pWalker->pParse; - int i, j, k; + int i, j, k, rc; SrcList *pTabList; ExprList *pEList; - struct SrcList_item *pFrom; + SrcItem *pFrom; sqlite3 *db = pParse->db; Expr *pE, *pRight, *pExpr; u16 selFlags = p->selFlags; @@ -4970,6 +5956,15 @@ static int selectExpander(Walker *pWalker, Select *p){ } pTabList = p->pSrc; pEList = p->pEList; + if( pParse->pWith && (p->selFlags & SF_View) ){ + if( p->pWith==0 ){ + p->pWith = (With*)sqlite3DbMallocZero(db, sizeof(With)); + if( p->pWith==0 ){ + return WRC_Abort; + } + } + p->pWith->bView = 1; + } sqlite3WithPush(pParse, p->pWith, 0); /* Make sure cursor numbers have been assigned to all entries in @@ -4984,12 +5979,8 @@ static int selectExpander(Walker *pWalker, Select *p){ for(i=0, pFrom=pTabList->a; i<pTabList->nSrc; i++, pFrom++){ Table *pTab; assert( pFrom->fg.isRecursive==0 || pFrom->pTab!=0 ); - if( pFrom->fg.isRecursive ) continue; - assert( pFrom->pTab==0 ); -#ifndef SQLITE_OMIT_CTE - if( withExpand(pWalker, pFrom) ) return WRC_Abort; - if( pFrom->pTab ) {} else -#endif + if( pFrom->pTab ) continue; + assert( pFrom->fg.isRecursive==0 ); if( pFrom->zName==0 ){ #ifndef SQLITE_OMIT_SUBQUERY Select *pSel = pFrom->pSelect; @@ -4999,6 +5990,12 @@ static int selectExpander(Walker *pWalker, Select *p){ if( sqlite3WalkSelect(pWalker, pSel) ) return WRC_Abort; if( sqlite3ExpandSubquery(pParse, pFrom) ) return WRC_Abort; #endif +#ifndef SQLITE_OMIT_CTE + }else if( (rc = resolveFromTermToCte(pParse, pWalker, pFrom))!=0 ){ + if( rc>1 ) return WRC_Abort; + pTab = pFrom->pTab; + assert( pTab!=0 ); +#endif }else{ /* An ordinary table or view name in the FROM clause */ assert( pFrom->pTab==0 ); @@ -5015,26 +6012,31 @@ static int selectExpander(Walker *pWalker, Select *p){ return WRC_Abort; } #if !defined(SQLITE_OMIT_VIEW) || !defined(SQLITE_OMIT_VIRTUALTABLE) - if( IsVirtual(pTab) || pTab->pSelect ){ + if( !IsOrdinaryTable(pTab) ){ i16 nCol; u8 eCodeOrig = pWalker->eCode; if( sqlite3ViewGetColumnNames(pParse, pTab) ) return WRC_Abort; assert( pFrom->pSelect==0 ); - if( pTab->pSelect && (db->flags & SQLITE_EnableView)==0 ){ - sqlite3ErrorMsg(pParse, "access to view \"%s\" prohibited", - pTab->zName); + if( IsView(pTab) ){ + if( (db->flags & SQLITE_EnableView)==0 + && pTab->pSchema!=db->aDb[1].pSchema + ){ + sqlite3ErrorMsg(pParse, "access to view \"%s\" prohibited", + pTab->zName); + } + pFrom->pSelect = sqlite3SelectDup(db, pTab->u.view.pSelect, 0); } #ifndef SQLITE_OMIT_VIRTUALTABLE - if( IsVirtual(pTab) + else if( ALWAYS(IsVirtual(pTab)) && pFrom->fg.fromDDL - && ALWAYS(pTab->pVTable!=0) - && pTab->pVTable->eVtabRisk > ((db->flags & SQLITE_TrustedSchema)!=0) + && ALWAYS(pTab->u.vtab.p!=0) + && pTab->u.vtab.p->eVtabRisk > ((db->flags & SQLITE_TrustedSchema)!=0) ){ sqlite3ErrorMsg(pParse, "unsafe use of virtual table \"%s\"", pTab->zName); } + assert( SQLITE_VTABRISK_Normal==1 && SQLITE_VTABRISK_High==2 ); #endif - pFrom->pSelect = sqlite3SelectDup(db, pTab->pSelect, 0); nCol = pTab->nCol; pTab->nCol = -1; pWalker->eCode = 1; /* Turn on Select.selId renumbering */ @@ -5046,14 +6048,15 @@ static int selectExpander(Walker *pWalker, Select *p){ } /* Locate the index named by the INDEXED BY clause, if any. */ - if( sqlite3IndexedByLookup(pParse, pFrom) ){ + if( pFrom->fg.isIndexedBy && sqlite3IndexedByLookup(pParse, pFrom) ){ return WRC_Abort; } } /* Process NATURAL keywords, and ON and USING clauses of joins. */ - if( pParse->nErr || db->mallocFailed || sqliteProcessJoin(pParse, p) ){ + assert( db->mallocFailed==0 || pParse->nErr!=0 ); + if( pParse->nErr || sqlite3ProcessJoin(pParse, p) ){ return WRC_Abort; } @@ -5101,7 +6104,7 @@ static int selectExpander(Walker *pWalker, Select *p){ pNew = sqlite3ExprListAppend(pParse, pNew, a[k].pExpr); if( pNew ){ pNew->a[pNew->nExpr-1].zEName = a[k].zEName; - pNew->a[pNew->nExpr-1].eEName = a[k].eEName; + pNew->a[pNew->nExpr-1].fg.eEName = a[k].fg.eEName; a[k].zEName = 0; } a[k].pExpr = 0; @@ -5110,102 +6113,174 @@ static int selectExpander(Walker *pWalker, Select *p){ ** expanded. */ int tableSeen = 0; /* Set to 1 when TABLE matches */ char *zTName = 0; /* text of name of TABLE */ + int iErrOfst; if( pE->op==TK_DOT ){ + assert( (selFlags & SF_NestedFrom)==0 ); assert( pE->pLeft!=0 ); assert( !ExprHasProperty(pE->pLeft, EP_IntValue) ); zTName = pE->pLeft->u.zToken; + assert( ExprUseWOfst(pE->pLeft) ); + iErrOfst = pE->pRight->w.iOfst; + }else{ + assert( ExprUseWOfst(pE) ); + iErrOfst = pE->w.iOfst; } for(i=0, pFrom=pTabList->a; i<pTabList->nSrc; i++, pFrom++){ - Table *pTab = pFrom->pTab; - Select *pSub = pFrom->pSelect; - char *zTabName = pFrom->zAlias; - const char *zSchemaName = 0; - int iDb; - if( zTabName==0 ){ + int nAdd; /* Number of cols including rowid */ + Table *pTab = pFrom->pTab; /* Table for this data source */ + ExprList *pNestedFrom; /* Result-set of a nested FROM clause */ + char *zTabName; /* AS name for this data source */ + const char *zSchemaName = 0; /* Schema name for this data source */ + int iDb; /* Schema index for this data src */ + IdList *pUsing; /* USING clause for pFrom[1] */ + + if( (zTabName = pFrom->zAlias)==0 ){ zTabName = pTab->zName; } if( db->mallocFailed ) break; - if( pSub==0 || (pSub->selFlags & SF_NestedFrom)==0 ){ - pSub = 0; + assert( (int)pFrom->fg.isNestedFrom == IsNestedFrom(pFrom->pSelect) ); + if( pFrom->fg.isNestedFrom ){ + assert( pFrom->pSelect!=0 ); + pNestedFrom = pFrom->pSelect->pEList; + assert( pNestedFrom!=0 ); + assert( pNestedFrom->nExpr==pTab->nCol ); + assert( VisibleRowid(pTab)==0 ); + }else{ if( zTName && sqlite3StrICmp(zTName, zTabName)!=0 ){ continue; } + pNestedFrom = 0; iDb = sqlite3SchemaToIndex(db, pTab->pSchema); zSchemaName = iDb>=0 ? db->aDb[iDb].zDbSName : "*"; } - for(j=0; j<pTab->nCol; j++){ - 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 */ - - assert( zName ); - if( zTName && pSub - && sqlite3MatchEName(&pSub->pEList->a[j], 0, zTName, 0)==0 - ){ - continue; + if( i+1<pTabList->nSrc + && pFrom[1].fg.isUsing + && (selFlags & SF_NestedFrom)!=0 + ){ + int ii; + pUsing = pFrom[1].u3.pUsing; + for(ii=0; ii<pUsing->nId; ii++){ + const char *zUName = pUsing->a[ii].zName; + pRight = sqlite3Expr(db, TK_ID, zUName); + sqlite3ExprSetErrorOffset(pRight, iErrOfst); + pNew = sqlite3ExprListAppend(pParse, pNew, pRight); + if( pNew ){ + struct ExprList_item *pX = &pNew->a[pNew->nExpr-1]; + assert( pX->zEName==0 ); + pX->zEName = sqlite3MPrintf(db,"..%s", zUName); + pX->fg.eEName = ENAME_TAB; + pX->fg.bUsingTerm = 1; + } } + }else{ + pUsing = 0; + } - /* If a column is marked as 'hidden', omit it from the expanded - ** result-set list unless the SELECT has the SF_IncludeHidden - ** bit set. - */ - if( (p->selFlags & SF_IncludeHidden)==0 - && IsHiddenColumn(&pTab->aCol[j]) - ){ - continue; - } - tableSeen = 1; + nAdd = pTab->nCol + (VisibleRowid(pTab) && (selFlags&SF_NestedFrom)); + for(j=0; j<nAdd; j++){ + const char *zName; + struct ExprList_item *pX; /* Newly added ExprList term */ + + if( j==pTab->nCol ){ + zName = sqlite3RowidAlias(pTab); + if( zName==0 ) continue; + }else{ + zName = pTab->aCol[j].zCnName; + + /* If pTab is actually an SF_NestedFrom sub-select, do not + ** expand any ENAME_ROWID columns. */ + if( pNestedFrom && pNestedFrom->a[j].fg.eEName==ENAME_ROWID ){ + continue; + } - if( i>0 && zTName==0 ){ - if( (pFrom->fg.jointype & JT_NATURAL)!=0 - && tableAndColumnIndex(pTabList, i, zName, 0, 0, 1) + if( zTName + && pNestedFrom + && sqlite3MatchEName(&pNestedFrom->a[j], 0, zTName, 0, 0)==0 + ){ + continue; + } + + /* If a column is marked as 'hidden', omit it from the expanded + ** result-set list unless the SELECT has the SF_IncludeHidden + ** bit set. + */ + if( (p->selFlags & SF_IncludeHidden)==0 + && IsHiddenColumn(&pTab->aCol[j]) + ){ + continue; + } + if( (pTab->aCol[j].colFlags & COLFLAG_NOEXPAND)!=0 + && zTName==0 + && (selFlags & (SF_NestedFrom))==0 ){ - /* In a NATURAL join, omit the join columns from the - ** table to the right of the join */ continue; } - if( sqlite3IdListIndex(pFrom->pUsing, zName)>=0 ){ + } + assert( zName ); + tableSeen = 1; + + if( i>0 && zTName==0 && (selFlags & SF_NestedFrom)==0 ){ + if( pFrom->fg.isUsing + && sqlite3IdListIndex(pFrom->u3.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 ){ + if( (pTabList->nSrc>1 + && ( (pFrom->fg.jointype & JT_LTORJ)==0 + || (selFlags & SF_NestedFrom)!=0 + || !inAnyUsingClause(zName,pFrom,pTabList->nSrc-i-1) + ) + ) + || IN_RENAME_OBJECT + ){ Expr *pLeft; pLeft = sqlite3Expr(db, TK_ID, zTabName); pExpr = sqlite3PExpr(pParse, TK_DOT, pLeft, pRight); + if( IN_RENAME_OBJECT && pE->pLeft ){ + sqlite3RenameTokenRemap(pParse, pLeft, pE->pLeft); + } if( zSchemaName ){ pLeft = sqlite3Expr(db, TK_ID, zSchemaName); pExpr = sqlite3PExpr(pParse, TK_DOT, pLeft, pExpr); } - if( longNames ){ - zColname = sqlite3MPrintf(db, "%s.%s", zTabName, zName); - zToFree = zColname; - } }else{ pExpr = pRight; } + sqlite3ExprSetErrorOffset(pExpr, iErrOfst); pNew = sqlite3ExprListAppend(pParse, pNew, pExpr); - sqlite3TokenInit(&sColname, zColname); - sqlite3ExprListSetName(pParse, pNew, &sColname, 0); - if( pNew && (p->selFlags & SF_NestedFrom)!=0 && !IN_RENAME_OBJECT ){ - struct ExprList_item *pX = &pNew->a[pNew->nExpr-1]; - sqlite3DbFree(db, pX->zEName); - if( pSub ){ - pX->zEName = sqlite3DbStrDup(db, pSub->pEList->a[j].zEName); + if( pNew==0 ){ + break; /* OOM */ + } + pX = &pNew->a[pNew->nExpr-1]; + assert( pX->zEName==0 ); + if( (selFlags & SF_NestedFrom)!=0 && !IN_RENAME_OBJECT ){ + if( pNestedFrom ){ + pX->zEName = sqlite3DbStrDup(db, pNestedFrom->a[j].zEName); testcase( pX->zEName==0 ); }else{ pX->zEName = sqlite3MPrintf(db, "%s.%s.%s", - zSchemaName, zTabName, zColname); + zSchemaName, zTabName, zName); testcase( pX->zEName==0 ); } - pX->eEName = ENAME_TAB; + pX->fg.eEName = (j==pTab->nCol ? ENAME_ROWID : ENAME_TAB); + if( (pFrom->fg.isUsing + && sqlite3IdListIndex(pFrom->u3.pUsing, zName)>=0) + || (pUsing && sqlite3IdListIndex(pUsing, zName)>=0) + || (j<pTab->nCol && (pTab->aCol[j].colFlags & COLFLAG_NOEXPAND)) + ){ + pX->fg.bNoExpand = 1; + } + }else if( longNames ){ + pX->zEName = sqlite3MPrintf(db, "%s.%s", zTabName, zName); + pX->fg.eEName = ENAME_NAME; + }else{ + pX->zEName = sqlite3DbStrDup(db, zName); + pX->fg.eEName = ENAME_NAME; } - sqlite3DbFree(db, zToFree); } } if( !tableSeen ){ @@ -5229,6 +6304,12 @@ static int selectExpander(Walker *pWalker, Select *p){ p->selFlags |= SF_ComplexResult; } } +#if TREETRACE_ENABLED + if( sqlite3TreeTrace & 0x8 ){ + TREETRACE(0x8,pParse,p,("After result-set wildcard expansion:\n")); + sqlite3TreeViewSelect(0, p, 0); + } +#endif return WRC_Continue; } @@ -5265,7 +6346,7 @@ static void sqlite3SelectExpand(Parse *pParse, Select *pSelect){ sqlite3WalkSelect(&w, pSelect); } w.xSelectCallback = selectExpander; - w.xSelectCallback2 = selectPopWith; + w.xSelectCallback2 = sqlite3SelectPopWith; w.eCode = 0; sqlite3WalkSelect(&w, pSelect); } @@ -5276,20 +6357,20 @@ static void sqlite3SelectExpand(Parse *pParse, Select *pSelect){ ** 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. +** For each FROM-clause subquery, add Column.zType, Column.zColl, and +** Column.affinity 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. +** by selectExpander() but the type and collation and affinity information +** was omitted at that point because identifiers had not yet been resolved. +** This routine is called after identifier resolution. */ static void selectAddSubqueryTypeInfo(Walker *pWalker, Select *p){ Parse *pParse; int i; SrcList *pTabList; - struct SrcList_item *pFrom; + SrcItem *pFrom; assert( p->selFlags & SF_Resolved ); if( p->selFlags & SF_HasTypeInfo ) return; @@ -5303,9 +6384,7 @@ static void selectAddSubqueryTypeInfo(Walker *pWalker, Select *p){ /* A sub-query in the FROM clause of a SELECT */ Select *pSel = pFrom->pSelect; if( pSel ){ - while( pSel->pPrior ) pSel = pSel->pPrior; - sqlite3SelectAddColumnTypeAndCollation(pParse, pTab, pSel, - SQLITE_AFF_NONE); + sqlite3SubqueryColumnTypes(pParse, pTab, pSel, SQLITE_AFF_NONE); } } } @@ -5350,15 +6429,194 @@ void sqlite3SelectPrep( NameContext *pOuterNC /* Name context for container */ ){ assert( p!=0 || pParse->db->mallocFailed ); + assert( pParse->db->pParse==pParse ); if( pParse->db->mallocFailed ) return; if( p->selFlags & SF_HasTypeInfo ) return; sqlite3SelectExpand(pParse, p); - if( pParse->nErr || pParse->db->mallocFailed ) return; + if( pParse->nErr ) return; sqlite3ResolveSelectNames(pParse, p, pOuterNC); - if( pParse->nErr || pParse->db->mallocFailed ) return; + if( pParse->nErr ) return; sqlite3SelectAddTypeInfo(pParse, p); } +#if TREETRACE_ENABLED +/* +** Display all information about an AggInfo object +*/ +static void printAggInfo(AggInfo *pAggInfo){ + int ii; + for(ii=0; ii<pAggInfo->nColumn; ii++){ + struct AggInfo_col *pCol = &pAggInfo->aCol[ii]; + sqlite3DebugPrintf( + "agg-column[%d] pTab=%s iTable=%d iColumn=%d iMem=%d" + " iSorterColumn=%d %s\n", + ii, pCol->pTab ? pCol->pTab->zName : "NULL", + pCol->iTable, pCol->iColumn, pAggInfo->iFirstReg+ii, + pCol->iSorterColumn, + ii>=pAggInfo->nAccumulator ? "" : " Accumulator"); + sqlite3TreeViewExpr(0, pAggInfo->aCol[ii].pCExpr, 0); + } + for(ii=0; ii<pAggInfo->nFunc; ii++){ + sqlite3DebugPrintf("agg-func[%d]: iMem=%d\n", + ii, pAggInfo->iFirstReg+pAggInfo->nColumn+ii); + sqlite3TreeViewExpr(0, pAggInfo->aFunc[ii].pFExpr, 0); + } +} +#endif /* TREETRACE_ENABLED */ + +/* +** Analyze the arguments to aggregate functions. Create new pAggInfo->aCol[] +** entries for columns that are arguments to aggregate functions but which +** are not otherwise used. +** +** The aCol[] entries in AggInfo prior to nAccumulator are columns that +** are referenced outside of aggregate functions. These might be columns +** that are part of the GROUP by clause, for example. Other database engines +** would throw an error if there is a column reference that is not in the +** GROUP BY clause and that is not part of an aggregate function argument. +** But SQLite allows this. +** +** The aCol[] entries beginning with the aCol[nAccumulator] and following +** are column references that are used exclusively as arguments to +** aggregate functions. This routine is responsible for computing +** (or recomputing) those aCol[] entries. +*/ +static void analyzeAggFuncArgs( + AggInfo *pAggInfo, + NameContext *pNC +){ + int i; + assert( pAggInfo!=0 ); + assert( pAggInfo->iFirstReg==0 ); + pNC->ncFlags |= NC_InAggFunc; + for(i=0; i<pAggInfo->nFunc; i++){ + Expr *pExpr = pAggInfo->aFunc[i].pFExpr; + assert( pExpr->op==TK_FUNCTION || pExpr->op==TK_AGG_FUNCTION ); + assert( ExprUseXList(pExpr) ); + sqlite3ExprAnalyzeAggList(pNC, pExpr->x.pList); + if( pExpr->pLeft ){ + assert( pExpr->pLeft->op==TK_ORDER ); + assert( ExprUseXList(pExpr->pLeft) ); + sqlite3ExprAnalyzeAggList(pNC, pExpr->pLeft->x.pList); + } +#ifndef SQLITE_OMIT_WINDOWFUNC + assert( !IsWindowFunc(pExpr) ); + if( ExprHasProperty(pExpr, EP_WinFunc) ){ + sqlite3ExprAnalyzeAggregates(pNC, pExpr->y.pWin->pFilter); + } +#endif + } + pNC->ncFlags &= ~NC_InAggFunc; +} + +/* +** An index on expressions is being used in the inner loop of an +** aggregate query with a GROUP BY clause. This routine attempts +** to adjust the AggInfo object to take advantage of index and to +** perhaps use the index as a covering index. +** +*/ +static void optimizeAggregateUseOfIndexedExpr( + Parse *pParse, /* Parsing context */ + Select *pSelect, /* The SELECT statement being processed */ + AggInfo *pAggInfo, /* The aggregate info */ + NameContext *pNC /* Name context used to resolve agg-func args */ +){ + assert( pAggInfo->iFirstReg==0 ); + assert( pSelect!=0 ); + assert( pSelect->pGroupBy!=0 ); + pAggInfo->nColumn = pAggInfo->nAccumulator; + if( ALWAYS(pAggInfo->nSortingColumn>0) ){ + int mx = pSelect->pGroupBy->nExpr - 1; + int j, k; + for(j=0; j<pAggInfo->nColumn; j++){ + k = pAggInfo->aCol[j].iSorterColumn; + if( k>mx ) mx = k; + } + pAggInfo->nSortingColumn = mx+1; + } + analyzeAggFuncArgs(pAggInfo, pNC); +#if TREETRACE_ENABLED + if( sqlite3TreeTrace & 0x20 ){ + IndexedExpr *pIEpr; + TREETRACE(0x20, pParse, pSelect, + ("AggInfo (possibly) adjusted for Indexed Exprs\n")); + sqlite3TreeViewSelect(0, pSelect, 0); + for(pIEpr=pParse->pIdxEpr; pIEpr; pIEpr=pIEpr->pIENext){ + printf("data-cursor=%d index={%d,%d}\n", + pIEpr->iDataCur, pIEpr->iIdxCur, pIEpr->iIdxCol); + sqlite3TreeViewExpr(0, pIEpr->pExpr, 0); + } + printAggInfo(pAggInfo); + } +#else + UNUSED_PARAMETER(pSelect); + UNUSED_PARAMETER(pParse); +#endif +} + +/* +** Walker callback for aggregateConvertIndexedExprRefToColumn(). +*/ +static int aggregateIdxEprRefToColCallback(Walker *pWalker, Expr *pExpr){ + AggInfo *pAggInfo; + struct AggInfo_col *pCol; + UNUSED_PARAMETER(pWalker); + if( pExpr->pAggInfo==0 ) return WRC_Continue; + if( pExpr->op==TK_AGG_COLUMN ) return WRC_Continue; + if( pExpr->op==TK_AGG_FUNCTION ) return WRC_Continue; + if( pExpr->op==TK_IF_NULL_ROW ) return WRC_Continue; + pAggInfo = pExpr->pAggInfo; + if( NEVER(pExpr->iAgg>=pAggInfo->nColumn) ) return WRC_Continue; + assert( pExpr->iAgg>=0 ); + pCol = &pAggInfo->aCol[pExpr->iAgg]; + pExpr->op = TK_AGG_COLUMN; + pExpr->iTable = pCol->iTable; + pExpr->iColumn = pCol->iColumn; + ExprClearProperty(pExpr, EP_Skip|EP_Collate|EP_Unlikely); + return WRC_Prune; +} + +/* +** Convert every pAggInfo->aFunc[].pExpr such that any node within +** those expressions that has pAppInfo set is changed into a TK_AGG_COLUMN +** opcode. +*/ +static void aggregateConvertIndexedExprRefToColumn(AggInfo *pAggInfo){ + int i; + Walker w; + memset(&w, 0, sizeof(w)); + w.xExprCallback = aggregateIdxEprRefToColCallback; + for(i=0; i<pAggInfo->nFunc; i++){ + sqlite3WalkExpr(&w, pAggInfo->aFunc[i].pFExpr); + } +} + + +/* +** Allocate a block of registers so that there is one register for each +** pAggInfo->aCol[] and pAggInfo->aFunc[] entry in pAggInfo. The first +** register in this block is stored in pAggInfo->iFirstReg. +** +** This routine may only be called once for each AggInfo object. Prior +** to calling this routine: +** +** * The aCol[] and aFunc[] arrays may be modified +** * The AggInfoColumnReg() and AggInfoFuncReg() macros may not be used +** +** After calling this routine: +** +** * The aCol[] and aFunc[] arrays are fixed +** * The AggInfoColumnReg() and AggInfoFuncReg() macros may be used +** +*/ +static void assignAggregateRegisters(Parse *pParse, AggInfo *pAggInfo){ + assert( pAggInfo!=0 ); + assert( pAggInfo->iFirstReg==0 ); + pAggInfo->iFirstReg = pParse->nMem + 1; + pParse->nMem += pAggInfo->nColumn + pAggInfo->nFunc; +} + /* ** Reset the aggregate accumulator. ** @@ -5372,35 +6630,54 @@ static void resetAccumulator(Parse *pParse, AggInfo *pAggInfo){ int i; struct AggInfo_func *pFunc; int nReg = pAggInfo->nFunc + pAggInfo->nColumn; + assert( pAggInfo->iFirstReg>0 ); + assert( pParse->db->pParse==pParse ); + assert( pParse->db->mallocFailed==0 || pParse->nErr!=0 ); if( nReg==0 ) return; - if( pParse->nErr || pParse->db->mallocFailed ) return; -#ifdef SQLITE_DEBUG - /* Verify that all AggInfo registers are within the range specified by - ** AggInfo.mnReg..AggInfo.mxReg */ - assert( nReg==pAggInfo->mxReg-pAggInfo->mnReg+1 ); - for(i=0; i<pAggInfo->nColumn; i++){ - assert( pAggInfo->aCol[i].iMem>=pAggInfo->mnReg - && pAggInfo->aCol[i].iMem<=pAggInfo->mxReg ); - } - for(i=0; i<pAggInfo->nFunc; i++){ - assert( pAggInfo->aFunc[i].iMem>=pAggInfo->mnReg - && pAggInfo->aFunc[i].iMem<=pAggInfo->mxReg ); - } -#endif - sqlite3VdbeAddOp3(v, OP_Null, 0, pAggInfo->mnReg, pAggInfo->mxReg); + if( pParse->nErr ) return; + sqlite3VdbeAddOp3(v, OP_Null, 0, pAggInfo->iFirstReg, + pAggInfo->iFirstReg+nReg-1); for(pFunc=pAggInfo->aFunc, i=0; i<pAggInfo->nFunc; i++, pFunc++){ if( pFunc->iDistinct>=0 ){ Expr *pE = pFunc->pFExpr; - assert( !ExprHasProperty(pE, EP_xIsSelect) ); + assert( ExprUseXList(pE) ); 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 = sqlite3KeyInfoFromExprList(pParse, pE->x.pList,0,0); - sqlite3VdbeAddOp4(v, OP_OpenEphemeral, pFunc->iDistinct, 0, 0, - (char*)pKeyInfo, P4_KEYINFO); + pFunc->iDistAddr = sqlite3VdbeAddOp4(v, OP_OpenEphemeral, + pFunc->iDistinct, 0, 0, (char*)pKeyInfo, P4_KEYINFO); + ExplainQueryPlan((pParse, 0, "USE TEMP B-TREE FOR %s(DISTINCT)", + pFunc->pFunc->zName)); + } + } + if( pFunc->iOBTab>=0 ){ + ExprList *pOBList; + KeyInfo *pKeyInfo; + int nExtra = 0; + assert( pFunc->pFExpr->pLeft!=0 ); + assert( pFunc->pFExpr->pLeft->op==TK_ORDER ); + assert( ExprUseXList(pFunc->pFExpr->pLeft) ); + pOBList = pFunc->pFExpr->pLeft->x.pList; + if( !pFunc->bOBUnique ){ + nExtra++; /* One extra column for the OP_Sequence */ + } + if( pFunc->bOBPayload ){ + /* extra columns for the function arguments */ + assert( ExprUseXList(pFunc->pFExpr) ); + nExtra += pFunc->pFExpr->x.pList->nExpr; } + pKeyInfo = sqlite3KeyInfoFromExprList(pParse, pOBList, 0, nExtra); + if( !pFunc->bOBUnique && pParse->nErr==0 ){ + pKeyInfo->nKeyField++; + } + sqlite3VdbeAddOp4(v, OP_OpenEphemeral, + pFunc->iOBTab, pOBList->nExpr+nExtra, 0, + (char*)pKeyInfo, P4_KEYINFO); + ExplainQueryPlan((pParse, 0, "USE TEMP B-TREE FOR %s(ORDER BY)", + pFunc->pFunc->zName)); } } } @@ -5414,24 +6691,71 @@ 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->pFExpr->x.pList; - assert( !ExprHasProperty(pF->pFExpr, EP_xIsSelect) ); - sqlite3VdbeAddOp2(v, OP_AggFinal, pF->iMem, pList ? pList->nExpr : 0); + ExprList *pList; + assert( ExprUseXList(pF->pFExpr) ); + pList = pF->pFExpr->x.pList; + if( pF->iOBTab>=0 ){ + /* For an ORDER BY aggregate, calls to OP_AggStep where deferred and + ** all content was stored in emphermal table pF->iOBTab. Extract that + ** content now (in ORDER BY order) and make all calls to OP_AggStep + ** before doing the OP_AggFinal call. */ + int iTop; /* Start of loop for extracting columns */ + int nArg; /* Number of columns to extract */ + int nKey; /* Key columns to be skipped */ + int regAgg; /* Extract into this array */ + int j; /* Loop counter */ + + nArg = pList->nExpr; + regAgg = sqlite3GetTempRange(pParse, nArg); + + if( pF->bOBPayload==0 ){ + nKey = 0; + }else{ + assert( pF->pFExpr->pLeft!=0 ); + assert( ExprUseXList(pF->pFExpr->pLeft) ); + assert( pF->pFExpr->pLeft->x.pList!=0 ); + nKey = pF->pFExpr->pLeft->x.pList->nExpr; + if( ALWAYS(!pF->bOBUnique) ) nKey++; + } + iTop = sqlite3VdbeAddOp1(v, OP_Rewind, pF->iOBTab); VdbeCoverage(v); + for(j=nArg-1; j>=0; j--){ + sqlite3VdbeAddOp3(v, OP_Column, pF->iOBTab, nKey+j, regAgg+j); + } + sqlite3VdbeAddOp3(v, OP_AggStep, 0, regAgg, AggInfoFuncReg(pAggInfo,i)); + sqlite3VdbeAppendP4(v, pF->pFunc, P4_FUNCDEF); + sqlite3VdbeChangeP5(v, (u8)nArg); + sqlite3VdbeAddOp2(v, OP_Next, pF->iOBTab, iTop+1); VdbeCoverage(v); + sqlite3VdbeJumpHere(v, iTop); + sqlite3ReleaseTempRange(pParse, regAgg, nArg); + } + sqlite3VdbeAddOp2(v, OP_AggFinal, AggInfoFuncReg(pAggInfo,i), + pList ? pList->nExpr : 0); sqlite3VdbeAppendP4(v, pF->pFunc, P4_FUNCDEF); } } - /* -** Update the accumulator memory cells for an aggregate based on -** the current cursor position. +** Generate code that will update the accumulator memory cells for an +** aggregate based on the current cursor position. ** ** If regAcc is non-zero and there are no min() or max() aggregates ** in pAggInfo, then only populate the pAggInfo->nAccumulator accumulator ** registers if register regAcc contains 0. The caller will take care ** of setting and clearing regAcc. +** +** For an ORDER BY aggregate, the actual accumulator memory cell update +** is deferred until after all input rows have been received, so that they +** can be run in the requested order. In that case, instead of invoking +** OP_AggStep to update the accumulator, just add the arguments that would +** have been passed into OP_AggStep into the sorting ephemeral table +** (along with the appropriate sort key). */ -static void updateAccumulator(Parse *pParse, int regAcc, AggInfo *pAggInfo){ +static void updateAccumulator( + Parse *pParse, + int regAcc, + AggInfo *pAggInfo, + int eDistinctType +){ Vdbe *v = pParse->pVdbe; int i; int regHit = 0; @@ -5439,66 +6763,120 @@ static void updateAccumulator(Parse *pParse, int regAcc, AggInfo *pAggInfo){ struct AggInfo_func *pF; struct AggInfo_col *pC; + assert( pAggInfo->iFirstReg>0 ); + if( pParse->nErr ) return; pAggInfo->directMode = 1; for(i=0, pF=pAggInfo->aFunc; i<pAggInfo->nFunc; i++, pF++){ int nArg; int addrNext = 0; int regAgg; - ExprList *pList = pF->pFExpr->x.pList; - assert( !ExprHasProperty(pF->pFExpr, EP_xIsSelect) ); + int regAggSz = 0; + int regDistinct = 0; + ExprList *pList; + assert( ExprUseXList(pF->pFExpr) ); assert( !IsWindowFunc(pF->pFExpr) ); + pList = pF->pFExpr->x.pList; if( ExprHasProperty(pF->pFExpr, EP_WinFunc) ){ Expr *pFilter = pF->pFExpr->y.pWin->pFilter; - if( pAggInfo->nAccumulator - && (pF->pFunc->funcFlags & SQLITE_FUNC_NEEDCOLL) + if( pAggInfo->nAccumulator + && (pF->pFunc->funcFlags & SQLITE_FUNC_NEEDCOLL) + && regAcc ){ + /* If regAcc==0, there there exists some min() or max() function + ** without a FILTER clause that will ensure the magnet registers + ** are populated. */ if( regHit==0 ) regHit = ++pParse->nMem; - /* If this is the first row of the group (regAcc==0), clear the + /* If this is the first row of the group (regAcc contains 0), clear the ** "magnet" register regHit so that the accumulator registers - ** are populated if the FILTER clause jumps over the the + ** are populated if the FILTER clause jumps over the the ** invocation of min() or max() altogether. Or, if this is not - ** the first row (regAcc==1), set the magnet register so that the - ** accumulators are not populated unless the min()/max() is invoked and - ** indicates that they should be. */ + ** the first row (regAcc contains 1), set the magnet register so that + ** the accumulators are not populated unless the min()/max() is invoked + ** and indicates that they should be. */ sqlite3VdbeAddOp2(v, OP_Copy, regAcc, regHit); } addrNext = sqlite3VdbeMakeLabel(pParse); sqlite3ExprIfFalse(pParse, pFilter, addrNext, SQLITE_JUMPIFNULL); } - if( pList ){ + if( pF->iOBTab>=0 ){ + /* Instead of invoking AggStep, we must push the arguments that would + ** have been passed to AggStep onto the sorting table. */ + int jj; /* Registered used so far in building the record */ + ExprList *pOBList; /* The ORDER BY clause */ + assert( pList!=0 ); + nArg = pList->nExpr; + assert( nArg>0 ); + assert( pF->pFExpr->pLeft!=0 ); + assert( pF->pFExpr->pLeft->op==TK_ORDER ); + assert( ExprUseXList(pF->pFExpr->pLeft) ); + pOBList = pF->pFExpr->pLeft->x.pList; + assert( pOBList!=0 ); + assert( pOBList->nExpr>0 ); + regAggSz = pOBList->nExpr; + if( !pF->bOBUnique ){ + regAggSz++; /* One register for OP_Sequence */ + } + if( pF->bOBPayload ){ + regAggSz += nArg; + } + regAggSz++; /* One extra register to hold result of MakeRecord */ + regAgg = sqlite3GetTempRange(pParse, regAggSz); + regDistinct = regAgg; + sqlite3ExprCodeExprList(pParse, pOBList, regAgg, 0, SQLITE_ECEL_DUP); + jj = pOBList->nExpr; + if( !pF->bOBUnique ){ + sqlite3VdbeAddOp2(v, OP_Sequence, pF->iOBTab, regAgg+jj); + jj++; + } + if( pF->bOBPayload ){ + regDistinct = regAgg+jj; + sqlite3ExprCodeExprList(pParse, pList, regDistinct, 0, SQLITE_ECEL_DUP); + } + }else if( pList ){ nArg = pList->nExpr; regAgg = sqlite3GetTempRange(pParse, nArg); + regDistinct = regAgg; sqlite3ExprCodeExprList(pParse, pList, regAgg, 0, SQLITE_ECEL_DUP); }else{ nArg = 0; regAgg = 0; } - if( pF->iDistinct>=0 ){ - if( addrNext==0 ){ + if( pF->iDistinct>=0 && pList ){ + if( addrNext==0 ){ addrNext = sqlite3VdbeMakeLabel(pParse); } - testcase( nArg==0 ); /* Error condition */ - testcase( nArg>1 ); /* Also an error */ - codeDistinct(pParse, pF->iDistinct, addrNext, 1, regAgg); - } - if( pF->pFunc->funcFlags & SQLITE_FUNC_NEEDCOLL ){ - CollSeq *pColl = 0; - struct ExprList_item *pItem; - int j; - 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); - } - if( !pColl ){ - pColl = pParse->db->pDfltColl; + pF->iDistinct = codeDistinct(pParse, eDistinctType, + pF->iDistinct, addrNext, pList, regDistinct); + } + if( pF->iOBTab>=0 ){ + /* Insert a new record into the ORDER BY table */ + sqlite3VdbeAddOp3(v, OP_MakeRecord, regAgg, regAggSz-1, + regAgg+regAggSz-1); + sqlite3VdbeAddOp4Int(v, OP_IdxInsert, pF->iOBTab, regAgg+regAggSz-1, + regAgg, regAggSz-1); + sqlite3ReleaseTempRange(pParse, regAgg, regAggSz); + }else{ + /* Invoke the AggStep function */ + if( pF->pFunc->funcFlags & SQLITE_FUNC_NEEDCOLL ){ + CollSeq *pColl = 0; + struct ExprList_item *pItem; + int j; + 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); + } + if( !pColl ){ + pColl = pParse->db->pDfltColl; + } + if( regHit==0 && pAggInfo->nAccumulator ) regHit = ++pParse->nMem; + sqlite3VdbeAddOp4(v, OP_CollSeq, regHit, 0, 0, + (char *)pColl, P4_COLLSEQ); } - if( regHit==0 && pAggInfo->nAccumulator ) regHit = ++pParse->nMem; - sqlite3VdbeAddOp4(v, OP_CollSeq, regHit, 0, 0, (char *)pColl, P4_COLLSEQ); + sqlite3VdbeAddOp3(v, OP_AggStep, 0, regAgg, AggInfoFuncReg(pAggInfo,i)); + sqlite3VdbeAppendP4(v, pF->pFunc, P4_FUNCDEF); + sqlite3VdbeChangeP5(v, (u8)nArg); + sqlite3ReleaseTempRange(pParse, regAgg, nArg); } - sqlite3VdbeAddOp3(v, OP_AggStep, 0, regAgg, pF->iMem); - sqlite3VdbeAppendP4(v, pF->pFunc, P4_FUNCDEF); - sqlite3VdbeChangeP5(v, (u8)nArg); - sqlite3ReleaseTempRange(pParse, regAgg, nArg); if( addrNext ){ sqlite3VdbeResolveLabel(v, addrNext); } @@ -5510,7 +6888,7 @@ static void updateAccumulator(Parse *pParse, int regAcc, AggInfo *pAggInfo){ addrHitTest = sqlite3VdbeAddOp1(v, OP_If, regHit); VdbeCoverage(v); } for(i=0, pC=pAggInfo->aCol; i<pAggInfo->nAccumulator; i++, pC++){ - sqlite3ExprCode(pParse, pC->pCExpr, pC->iMem); + sqlite3ExprCode(pParse, pC->pCExpr, AggInfoColumnReg(pAggInfo,i)); } pAggInfo->directMode = 0; @@ -5531,7 +6909,7 @@ static void explainSimpleCount( ){ if( pParse->explain==2 ){ int bCover = (pIdx!=0 && (HasRowid(pTab) || !IsPrimaryKeyIndex(pIdx))); - sqlite3VdbeExplain(pParse, 0, "SCAN TABLE %s%s%s", + sqlite3VdbeExplain(pParse, 0, "SCAN %s%s%s", pTab->zName, bCover ? " USING COVERING INDEX " : "", bCover ? pIdx->zName : "" @@ -5545,10 +6923,10 @@ static void explainSimpleCount( /* ** sqlite3WalkExpr() callback used by havingToWhere(). ** -** If the node passed to the callback is a TK_AND node, return +** If the node passed to the callback is a TK_AND node, return ** WRC_Continue to tell sqlite3WalkExpr() to iterate through child nodes. ** -** Otherwise, return WRC_Prune. In this case, also check if the +** Otherwise, return WRC_Prune. In this case, also check if the ** sub-expression matches the criteria for being moved to the WHERE ** clause. If so, add it to the WHERE clause and replace the sub-expression ** within the HAVING expression with a constant "1". @@ -5556,7 +6934,17 @@ static void explainSimpleCount( static int havingToWhereExprCb(Walker *pWalker, Expr *pExpr){ if( pExpr->op!=TK_AND ){ Select *pS = pWalker->u.pSelect; - if( sqlite3ExprIsConstantOrGroupBy(pWalker->pParse, pExpr, pS->pGroupBy) ){ + /* This routine is called before the HAVING clause of the current + ** SELECT is analyzed for aggregates. So if pExpr->pAggInfo is set + ** here, it indicates that the expression is a correlated reference to a + ** column from an outer aggregate query, or an aggregate function that + ** belongs to an outer query. Do not move the expression to the WHERE + ** clause in this obscure case, as doing so may corrupt the outer Select + ** statements AggInfo structure. */ + if( sqlite3ExprIsConstantOrGroupBy(pWalker->pParse, pExpr, pS->pGroupBy) + && ExprAlwaysFalse(pExpr)==0 + && pExpr->pAggInfo==0 + ){ sqlite3 *db = pWalker->pParse->db; Expr *pNew = sqlite3Expr(db, TK_INTEGER, "1"); if( pNew ){ @@ -5594,26 +6982,33 @@ static void havingToWhere(Parse *pParse, Select *p){ sWalker.xExprCallback = havingToWhereExprCb; sWalker.u.pSelect = p; sqlite3WalkExpr(&sWalker, p->pHaving); -#if SELECTTRACE_ENABLED - if( sWalker.eCode && (sqlite3SelectTrace & 0x100)!=0 ){ - SELECTTRACE(0x100,pParse,p,("Move HAVING terms into WHERE:\n")); +#if TREETRACE_ENABLED + if( sWalker.eCode && (sqlite3TreeTrace & 0x100)!=0 ){ + TREETRACE(0x100,pParse,p,("Move HAVING terms into WHERE:\n")); sqlite3TreeViewSelect(0, p, 0); } #endif } /* -** Check to see if the pThis entry of pTabList is a self-join of a prior view. -** If it is, then return the SrcList_item for the prior view. If it is not, -** then return 0. +** Check to see if the pThis entry of pTabList is a self-join of another view. +** Search FROM-clause entries in the range of iFirst..iEnd, including iFirst +** but stopping before iEnd. +** +** If pThis is a self-join, then return the SrcItem for the first other +** instance of that view found. If pThis is not a self-join then return 0. */ -static struct SrcList_item *isSelfJoinView( +static SrcItem *isSelfJoinView( SrcList *pTabList, /* Search for self-joins in this FROM clause */ - struct SrcList_item *pThis /* Search for prior reference to this subquery */ + SrcItem *pThis, /* Search for prior reference to this subquery */ + int iFirst, int iEnd /* Range of FROM-clause entries to search. */ ){ - struct SrcList_item *pItem; - for(pItem = pTabList->a; pItem<pThis; pItem++){ + SrcItem *pItem; + assert( pThis->pSelect!=0 ); + if( pThis->pSelect->selFlags & SF_PushDown ) return 0; + while( iFirst<iEnd ){ Select *pS1; + pItem = &pTabList->a[iFirst++]; if( pItem->pSelect==0 ) continue; if( pItem->fg.viaCoroutine ) continue; if( pItem->zName==0 ) continue; @@ -5627,9 +7022,7 @@ static struct SrcList_item *isSelfJoinView( ** names in the same FROM clause. */ continue; } - if( sqlite3ExprCompare(0, pThis->pSelect->pWhere, pS1->pWhere, -1) - || sqlite3ExprCompare(0, pThis->pSelect->pHaving, pS1->pHaving, -1) - ){ + if( pItem->pSelect->selFlags & SF_PushDown ){ /* The view was modified by some other optimization such as ** pushDownWhereTerms() */ continue; @@ -5639,7 +7032,15 @@ static struct SrcList_item *isSelfJoinView( return 0; } -#ifdef SQLITE_COUNTOFVIEW_OPTIMIZATION +/* +** Deallocate a single AggInfo object +*/ +static void agginfoFree(sqlite3 *db, AggInfo *p){ + sqlite3DbFree(db, p->aCol); + sqlite3DbFree(db, p->aFunc); + sqlite3DbFreeNN(db, p); +} + /* ** Attempt to transform a query of the form ** @@ -5667,21 +7068,28 @@ static int countOfViewOptimization(Parse *pParse, Select *p){ if( (p->selFlags & SF_Aggregate)==0 ) return 0; /* This is an aggregate */ if( p->pEList->nExpr!=1 ) return 0; /* Single result column */ if( p->pWhere ) return 0; + if( p->pHaving ) return 0; if( p->pGroupBy ) return 0; + if( p->pOrderBy ) return 0; pExpr = p->pEList->a[0].pExpr; if( pExpr->op!=TK_AGG_FUNCTION ) return 0; /* Result is an aggregate */ + assert( ExprUseUToken(pExpr) ); if( sqlite3_stricmp(pExpr->u.zToken,"count") ) return 0; /* Is count() */ + assert( ExprUseXList(pExpr) ); if( pExpr->x.pList!=0 ) return 0; /* Must be count(*) */ if( p->pSrc->nSrc!=1 ) return 0; /* One table in FROM */ + if( ExprHasProperty(pExpr, EP_WinFunc) ) return 0;/* Not a window function */ pSub = p->pSrc->a[0].pSelect; if( pSub==0 ) return 0; /* The FROM is a subquery */ - if( pSub->pPrior==0 ) return 0; /* Must be a compound ry */ + if( pSub->pPrior==0 ) return 0; /* Must be a compound */ + if( pSub->selFlags & SF_CopyCte ) return 0; /* Not a CTE */ do{ if( pSub->op!=TK_ALL && pSub->pPrior ) return 0; /* Must be UNION ALL */ if( pSub->pWhere ) return 0; /* No WHERE clause */ if( pSub->pLimit ) return 0; /* No LIMIT clause */ if( pSub->selFlags & SF_Aggregate ) return 0; /* Not an aggregate */ - pSub = pSub->pPrior; /* Repeat over compound */ + assert( pSub->pHaving==0 ); /* Due to the previous */ + pSub = pSub->pPrior; /* Repeat over compound */ }while( pSub ); /* If we reach this point then it is OK to perform the transformation */ @@ -5716,18 +7124,102 @@ static int countOfViewOptimization(Parse *pParse, Select *p){ p->pEList->a[0].pExpr = pExpr; p->selFlags &= ~SF_Aggregate; -#if SELECTTRACE_ENABLED - if( sqlite3SelectTrace & 0x400 ){ - SELECTTRACE(0x400,pParse,p,("After count-of-view optimization:\n")); +#if TREETRACE_ENABLED + if( sqlite3TreeTrace & 0x200 ){ + TREETRACE(0x200,pParse,p,("After count-of-view optimization:\n")); sqlite3TreeViewSelect(0, p, 0); } #endif return 1; } -#endif /* SQLITE_COUNTOFVIEW_OPTIMIZATION */ /* -** Generate code for the SELECT statement given in the p argument. +** If any term of pSrc, or any SF_NestedFrom sub-query, is not the same +** as pSrcItem but has the same alias as p0, then return true. +** Otherwise return false. +*/ +static int sameSrcAlias(SrcItem *p0, SrcList *pSrc){ + int i; + for(i=0; i<pSrc->nSrc; i++){ + SrcItem *p1 = &pSrc->a[i]; + if( p1==p0 ) continue; + if( p0->pTab==p1->pTab && 0==sqlite3_stricmp(p0->zAlias, p1->zAlias) ){ + return 1; + } + if( p1->pSelect + && (p1->pSelect->selFlags & SF_NestedFrom)!=0 + && sameSrcAlias(p0, p1->pSelect->pSrc) + ){ + return 1; + } + } + return 0; +} + +/* +** Return TRUE (non-zero) if the i-th entry in the pTabList SrcList can +** be implemented as a co-routine. The i-th entry is guaranteed to be +** a subquery. +** +** The subquery is implemented as a co-routine if all of the following are +** true: +** +** (1) The subquery will likely be implemented in the outer loop of +** the query. This will be the case if any one of the following +** conditions hold: +** (a) The subquery is the only term in the FROM clause +** (b) The subquery is the left-most term and a CROSS JOIN or similar +** requires it to be the outer loop +** (c) All of the following are true: +** (i) The subquery is the left-most subquery in the FROM clause +** (ii) There is nothing that would prevent the subquery from +** being used as the outer loop if the sqlite3WhereBegin() +** routine nominates it to that position. +** (iii) The query is not a UPDATE ... FROM +** (2) The subquery is not a CTE that should be materialized because +** (a) the AS MATERIALIZED keyword is used, or +** (b) the CTE is used multiple times and does not have the +** NOT MATERIALIZED keyword +** (3) The subquery is not part of a left operand for a RIGHT JOIN +** (4) The SQLITE_Coroutine optimization disable flag is not set +** (5) The subquery is not self-joined +*/ +static int fromClauseTermCanBeCoroutine( + Parse *pParse, /* Parsing context */ + SrcList *pTabList, /* FROM clause */ + int i, /* Which term of the FROM clause holds the subquery */ + int selFlags /* Flags on the SELECT statement */ +){ + SrcItem *pItem = &pTabList->a[i]; + if( pItem->fg.isCte ){ + const CteUse *pCteUse = pItem->u2.pCteUse; + if( pCteUse->eM10d==M10d_Yes ) return 0; /* (2a) */ + if( pCteUse->nUse>=2 && pCteUse->eM10d!=M10d_No ) return 0; /* (2b) */ + } + if( pTabList->a[0].fg.jointype & JT_LTORJ ) return 0; /* (3) */ + if( OptimizationDisabled(pParse->db, SQLITE_Coroutines) ) return 0; /* (4) */ + if( isSelfJoinView(pTabList, pItem, i+1, pTabList->nSrc)!=0 ){ + return 0; /* (5) */ + } + if( i==0 ){ + if( pTabList->nSrc==1 ) return 1; /* (1a) */ + if( pTabList->a[1].fg.jointype & JT_CROSS ) return 1; /* (1b) */ + if( selFlags & SF_UpdateFrom ) return 0; /* (1c-iii) */ + return 1; + } + if( selFlags & SF_UpdateFrom ) return 0; /* (1c-iii) */ + while( 1 /*exit-by-break*/ ){ + if( pItem->fg.jointype & (JT_OUTER|JT_CROSS) ) return 0; /* (1c-ii) */ + if( i==0 ) break; + i--; + pItem--; + if( pItem->pSelect!=0 ) return 0; /* (1c-i) */ + } + return 1; +} + +/* +** Generate code for the SELECT statement given in the p argument. ** ** The results are returned according to the SelectDest structure. ** See comments in sqliteInt.h for further information. @@ -5763,15 +7255,21 @@ int sqlite3Select( u8 minMaxFlag; /* Flag for min/max queries */ db = pParse->db; + assert( pParse==db->pParse ); v = sqlite3GetVdbe(pParse); - if( p==0 || db->mallocFailed || pParse->nErr ){ + if( p==0 || pParse->nErr ){ return 1; } + assert( db->mallocFailed==0 ); if( sqlite3AuthCheck(pParse, SQLITE_SELECT, 0, 0, 0) ) return 1; -#if SELECTTRACE_ENABLED - SELECTTRACE(1,pParse,p, ("begin processing:\n", pParse->addrExplain)); - if( sqlite3SelectTrace & 0x100 ){ - sqlite3TreeViewSelect(0, p, 0); +#if TREETRACE_ENABLED + TREETRACE(0x1,pParse,p, ("begin processing:\n", pParse->addrExplain)); + if( sqlite3TreeTrace & 0x10000 ){ + if( (sqlite3TreeTrace & 0x10001)==0x10000 ){ + sqlite3TreeViewLine(0, "In sqlite3Select() at %s:%d", + __FILE__, __LINE__); + } + sqlite3ShowSelect(p); } #endif @@ -5779,43 +7277,78 @@ int sqlite3Select( assert( p->pOrderBy==0 || pDest->eDest!=SRT_Fifo ); assert( p->pOrderBy==0 || pDest->eDest!=SRT_DistQueue ); assert( p->pOrderBy==0 || pDest->eDest!=SRT_Queue ); - if( IgnorableOrderby(pDest) ){ - assert(pDest->eDest==SRT_Exists || pDest->eDest==SRT_Union || - pDest->eDest==SRT_Except || pDest->eDest==SRT_Discard || - pDest->eDest==SRT_Queue || pDest->eDest==SRT_DistFifo || - pDest->eDest==SRT_DistQueue || pDest->eDest==SRT_Fifo); - /* 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; + if( IgnorableDistinct(pDest) ){ + assert(pDest->eDest==SRT_Exists || pDest->eDest==SRT_Union || + pDest->eDest==SRT_Except || pDest->eDest==SRT_Discard || + pDest->eDest==SRT_DistQueue || pDest->eDest==SRT_DistFifo ); + /* All of these destinations are also able to ignore the ORDER BY clause */ + if( p->pOrderBy ){ +#if TREETRACE_ENABLED + TREETRACE(0x800,pParse,p, ("dropping superfluous ORDER BY:\n")); + if( sqlite3TreeTrace & 0x800 ){ + sqlite3TreeViewExprList(0, p->pOrderBy, 0, "ORDERBY"); + } +#endif + sqlite3ParserAddCleanup(pParse, + (void(*)(sqlite3*,void*))sqlite3ExprListDelete, + p->pOrderBy); + testcase( pParse->earlyCleanup ); + p->pOrderBy = 0; + } p->selFlags &= ~SF_Distinct; p->selFlags |= SF_NoopOrderBy; } sqlite3SelectPrep(pParse, p, 0); - if( pParse->nErr || db->mallocFailed ){ + if( pParse->nErr ){ goto select_end; } + assert( db->mallocFailed==0 ); assert( p->pEList!=0 ); -#if SELECTTRACE_ENABLED - if( sqlite3SelectTrace & 0x104 ){ - SELECTTRACE(0x104,pParse,p, ("after name resolution:\n")); +#if TREETRACE_ENABLED + if( sqlite3TreeTrace & 0x10 ){ + TREETRACE(0x10,pParse,p, ("after name resolution:\n")); sqlite3TreeViewSelect(0, p, 0); } #endif + /* If the SF_UFSrcCheck flag is set, then this function is being called + ** as part of populating the temp table for an UPDATE...FROM statement. + ** In this case, it is an error if the target object (pSrc->a[0]) name + ** or alias is duplicated within FROM clause (pSrc->a[1..n]). + ** + ** Postgres disallows this case too. The reason is that some other + ** systems handle this case differently, and not all the same way, + ** which is just confusing. To avoid this, we follow PG's lead and + ** disallow it altogether. */ + if( p->selFlags & SF_UFSrcCheck ){ + SrcItem *p0 = &p->pSrc->a[0]; + if( sameSrcAlias(p0, p->pSrc) ){ + sqlite3ErrorMsg(pParse, + "target object/alias may not appear in FROM clause: %s", + p0->zAlias ? p0->zAlias : p0->pTab->zName + ); + goto select_end; + } + + /* Clear the SF_UFSrcCheck flag. The check has already been performed, + ** and leaving this flag set can cause errors if a compound sub-query + ** in p->pSrc is flattened into this query and this function called + ** again as part of compound SELECT processing. */ + p->selFlags &= ~SF_UFSrcCheck; + } + if( pDest->eDest==SRT_Output ){ - generateColumnNames(pParse, p); + sqlite3GenerateColumnNames(pParse, p); } #ifndef SQLITE_OMIT_WINDOWFUNC - rc = sqlite3WindowRewrite(pParse, p); - if( rc ){ - assert( db->mallocFailed || pParse->nErr>0 ); + if( sqlite3WindowRewrite(pParse, p) ){ + assert( pParse->nErr ); goto select_end; } -#if SELECTTRACE_ENABLED - if( p->pWin && (sqlite3SelectTrace & 0x108)!=0 ){ - SELECTTRACE(0x104,pParse,p, ("after window rewrite:\n")); +#if TREETRACE_ENABLED + if( p->pWin && (sqlite3TreeTrace & 0x40)!=0 ){ + TREETRACE(0x40,pParse,p, ("after window rewrite:\n")); sqlite3TreeViewSelect(0, p, 0); } #endif @@ -5830,7 +7363,7 @@ int sqlite3Select( */ #if !defined(SQLITE_OMIT_SUBQUERY) || !defined(SQLITE_OMIT_VIEW) for(i=0; !p->pPrior && i<pTabList->nSrc; i++){ - struct SrcList_item *pItem = &pTabList->a[i]; + SrcItem *pItem = &pTabList->a[i]; Select *pSub = pItem->pSelect; Table *pTab = pItem->pTab; @@ -5839,20 +7372,58 @@ int sqlite3Select( ** to a real table */ assert( pTab!=0 ); - /* Convert LEFT JOIN into JOIN if there are terms of the right table - ** of the LEFT JOIN used in the WHERE clause. + /* Try to simplify joins: + ** + ** LEFT JOIN -> JOIN + ** RIGHT JOIN -> JOIN + ** FULL JOIN -> RIGHT JOIN + ** + ** If terms of the i-th table are used in the WHERE clause in such a + ** way that the i-th table cannot be the NULL row of a join, then + ** perform the appropriate simplification. This is called + ** "OUTER JOIN strength reduction" in the SQLite documentation. */ - if( (pItem->fg.jointype & JT_LEFT)!=0 - && sqlite3ExprImpliesNonNullRow(p->pWhere, pItem->iCursor) + if( (pItem->fg.jointype & (JT_LEFT|JT_LTORJ))!=0 + && sqlite3ExprImpliesNonNullRow(p->pWhere, pItem->iCursor, + pItem->fg.jointype & JT_LTORJ) && OptimizationEnabled(db, SQLITE_SimplifyJoin) ){ - SELECTTRACE(0x100,pParse,p, - ("LEFT-JOIN simplifies to JOIN on term %d\n",i)); - pItem->fg.jointype &= ~(JT_LEFT|JT_OUTER); - unsetJoinExpr(p->pWhere, pItem->iCursor); + if( pItem->fg.jointype & JT_LEFT ){ + if( pItem->fg.jointype & JT_RIGHT ){ + TREETRACE(0x1000,pParse,p, + ("FULL-JOIN simplifies to RIGHT-JOIN on term %d\n",i)); + pItem->fg.jointype &= ~JT_LEFT; + }else{ + TREETRACE(0x1000,pParse,p, + ("LEFT-JOIN simplifies to JOIN on term %d\n",i)); + pItem->fg.jointype &= ~(JT_LEFT|JT_OUTER); + unsetJoinExpr(p->pWhere, pItem->iCursor, 0); + } + } + if( pItem->fg.jointype & JT_LTORJ ){ + for(j=i+1; j<pTabList->nSrc; j++){ + SrcItem *pI2 = &pTabList->a[j]; + if( pI2->fg.jointype & JT_RIGHT ){ + if( pI2->fg.jointype & JT_LEFT ){ + TREETRACE(0x1000,pParse,p, + ("FULL-JOIN simplifies to LEFT-JOIN on term %d\n",j)); + pI2->fg.jointype &= ~JT_RIGHT; + }else{ + TREETRACE(0x1000,pParse,p, + ("RIGHT-JOIN simplifies to JOIN on term %d\n",j)); + pI2->fg.jointype &= ~(JT_RIGHT|JT_OUTER); + unsetJoinExpr(p->pWhere, pI2->iCursor, 1); + } + } + } + for(j=pTabList->nSrc-1; j>=0; j--){ + pTabList->a[j].fg.jointype &= ~JT_LTORJ; + if( pTabList->a[j].fg.jointype & JT_RIGHT ) break; + } + } } - /* No futher action if this term of the FROM clause is no a subquery */ + /* No further action if this term of the FROM clause is not a subquery */ if( pSub==0 ) continue; /* Catch mismatch in the declared columns of a view and the number of @@ -5863,6 +7434,14 @@ int sqlite3Select( goto select_end; } + /* Do not attempt the usual optimizations (flattening and ORDER BY + ** elimination) on a MATERIALIZED common table expression because + ** a MATERIALIZED common table expression is an optimization fence. + */ + if( pItem->fg.isCte && pItem->u2.pCteUse->eM10d==M10d_Yes ){ + continue; + } + /* Do not try to flatten an aggregate subquery. ** ** Flattening an aggregate subquery is only possible if the outer query @@ -5873,6 +7452,43 @@ int sqlite3Select( if( (pSub->selFlags & SF_Aggregate)!=0 ) continue; assert( pSub->pGroupBy==0 ); + /* If a FROM-clause subquery has an ORDER BY clause that is not + ** really doing anything, then delete it now so that it does not + ** interfere with query flattening. See the discussion at + ** https://sqlite.org/forum/forumpost/2d76f2bcf65d256a + ** + ** Beware of these cases where the ORDER BY clause may not be safely + ** omitted: + ** + ** (1) There is also a LIMIT clause + ** (2) The subquery was added to help with window-function + ** processing + ** (3) The subquery is in the FROM clause of an UPDATE + ** (4) The outer query uses an aggregate function other than + ** the built-in count(), min(), or max(). + ** (5) The ORDER BY isn't going to accomplish anything because + ** one of: + ** (a) The outer query has a different ORDER BY clause + ** (b) The subquery is part of a join + ** See forum post 062d576715d277c8 + ** + ** Also retain the ORDER BY if the OmitOrderBy optimization is disabled. + */ + if( pSub->pOrderBy!=0 + && (p->pOrderBy!=0 || pTabList->nSrc>1) /* Condition (5) */ + && pSub->pLimit==0 /* Condition (1) */ + && (pSub->selFlags & SF_OrderByReqd)==0 /* Condition (2) */ + && (p->selFlags & SF_OrderByReqd)==0 /* Condition (3) and (4) */ + && OptimizationEnabled(db, SQLITE_OmitOrderBy) + ){ + TREETRACE(0x800,pParse,p, + ("omit superfluous ORDER BY on %r FROM-clause subquery\n",i+1)); + sqlite3ParserAddCleanup(pParse, + (void(*)(sqlite3*,void*))sqlite3ExprListDelete, + pSub->pOrderBy); + pSub->pOrderBy = 0; + } + /* If the outer query contains a "complex" result set (that is, ** if the result set of the outer query uses functions or subqueries) ** and if the subquery contains an ORDER BY clause and if @@ -5895,7 +7511,7 @@ int sqlite3Select( && i==0 && (p->selFlags & SF_ComplexResult)!=0 && (pTabList->nSrc==1 - || (pTabList->a[1].fg.jointype&(JT_LEFT|JT_CROSS))!=0) + || (pTabList->a[1].fg.jointype&(JT_OUTER|JT_CROSS))!=0) ){ continue; } @@ -5919,9 +7535,9 @@ int sqlite3Select( */ if( p->pPrior ){ rc = multiSelect(pParse, p, pDest); -#if SELECTTRACE_ENABLED - SELECTTRACE(0x1,pParse,p,("end compound-select processing\n")); - if( (sqlite3SelectTrace & 0x2000)!=0 && ExplainQueryPlanParent(pParse)==0 ){ +#if TREETRACE_ENABLED + TREETRACE(0x400,pParse,p,("end compound-select processing\n")); + if( (sqlite3TreeTrace & 0x400)!=0 && ExplainQueryPlanParent(pParse)==0 ){ sqlite3TreeViewSelect(0, p, 0); } #endif @@ -5935,36 +7551,35 @@ int sqlite3Select( ** as the equivalent optimization will be handled by query planner in ** sqlite3WhereBegin(). */ - if( pTabList->nSrc>1 + if( p->pWhere!=0 + && p->pWhere->op==TK_AND && OptimizationEnabled(db, SQLITE_PropagateConst) && propagateConstants(pParse, p) ){ -#if SELECTTRACE_ENABLED - if( sqlite3SelectTrace & 0x100 ){ - SELECTTRACE(0x100,pParse,p,("After constant propagation:\n")); +#if TREETRACE_ENABLED + if( sqlite3TreeTrace & 0x2000 ){ + TREETRACE(0x2000,pParse,p,("After constant propagation:\n")); sqlite3TreeViewSelect(0, p, 0); } #endif }else{ - SELECTTRACE(0x100,pParse,p,("Constant propagation not helpful\n")); + TREETRACE(0x2000,pParse,p,("Constant propagation not helpful\n")); } -#ifdef SQLITE_COUNTOFVIEW_OPTIMIZATION if( OptimizationEnabled(db, SQLITE_QueryFlattener|SQLITE_CountOfView) && countOfViewOptimization(pParse, p) ){ if( db->mallocFailed ) goto select_end; - pEList = p->pEList; pTabList = p->pSrc; } -#endif /* For each term in the FROM clause, do two things: ** (1) Authorized unreferenced tables ** (2) Generate code for all sub-queries */ for(i=0; i<pTabList->nSrc; i++){ - struct SrcList_item *pItem = &pTabList->a[i]; + SrcItem *pItem = &pTabList->a[i]; + SrcItem *pPrior; SelectDest dest; Select *pSub; #if !defined(SQLITE_OMIT_SUBQUERY) || !defined(SQLITE_OMIT_VIEW) @@ -5997,19 +7612,8 @@ int sqlite3Select( pSub = pItem->pSelect; if( pSub==0 ) continue; - /* The code for a subquery should only be generated once, though it is - ** technically harmless for it to be generated multiple times. The - ** following assert() will detect if something changes to cause - ** the same subquery to be coded multiple times, as a signal to the - ** developers to try to optimize the situation. - ** - ** Update 2019-07-24: - ** See ticket https://sqlite.org/src/tktview/c52b09c7f38903b1311cec40. - ** The dbsqlfuzz fuzzer found a case where the same subquery gets - ** coded twice. So this assert() now becomes a testcase(). It should - ** be very rare, though. - */ - testcase( pItem->addrFillSub!=0 ); + /* The code for a subquery should only be generated once. */ + assert( pItem->addrFillSub==0 ); /* Increment Parse.nHeight by the height of the largest expression ** tree referred to by this, the parent select. The child select @@ -6024,47 +7628,55 @@ int sqlite3Select( ** inside the subquery. This can help the subquery to run more efficiently. */ if( OptimizationEnabled(db, SQLITE_PushDown) - && pushDownWhereTerms(pParse, pSub, p->pWhere, pItem->iCursor, - (pItem->fg.jointype & JT_OUTER)!=0) + && (pItem->fg.isCte==0 + || (pItem->u2.pCteUse->eM10d!=M10d_Yes && pItem->u2.pCteUse->nUse<2)) + && pushDownWhereTerms(pParse, pSub, p->pWhere, pTabList, i) ){ -#if SELECTTRACE_ENABLED - if( sqlite3SelectTrace & 0x100 ){ - SELECTTRACE(0x100,pParse,p, +#if TREETRACE_ENABLED + if( sqlite3TreeTrace & 0x4000 ){ + TREETRACE(0x4000,pParse,p, ("After WHERE-clause push-down into subquery %d:\n", pSub->selId)); sqlite3TreeViewSelect(0, p, 0); } #endif + assert( pItem->pSelect && (pItem->pSelect->selFlags & SF_PushDown)!=0 ); }else{ - SELECTTRACE(0x100,pParse,p,("Push-down not possible\n")); + TREETRACE(0x4000,pParse,p,("Push-down not possible\n")); + } + + /* Convert unused result columns of the subquery into simple NULL + ** expressions, to avoid unneeded searching and computation. + */ + if( OptimizationEnabled(db, SQLITE_NullUnusedCols) + && disableUnusedSubqueryResultColumns(pItem) + ){ +#if TREETRACE_ENABLED + if( sqlite3TreeTrace & 0x4000 ){ + TREETRACE(0x4000,pParse,p, + ("Change unused result columns to NULL for subquery %d:\n", + pSub->selId)); + sqlite3TreeViewSelect(0, p, 0); + } +#endif } zSavedAuthContext = pParse->zAuthContext; pParse->zAuthContext = pItem->zName; /* Generate code to implement the subquery - ** - ** The subquery is implemented as a co-routine if the subquery is - ** guaranteed to be the outer loop (so that it does not need to be - ** computed more than once) - ** - ** TODO: Are there other reasons beside (1) to use a co-routine - ** implementation? */ - if( i==0 - && (pTabList->nSrc==1 - || (pTabList->a[1].fg.jointype&(JT_LEFT|JT_CROSS))!=0) /* (1) */ - ){ + if( fromClauseTermCanBeCoroutine(pParse, pTabList, i, p->selFlags) ){ /* Implement a co-routine that will return a single row of the result ** set on each invocation. */ int addrTop = sqlite3VdbeCurrentAddr(v)+1; - + pItem->regReturn = ++pParse->nMem; sqlite3VdbeAddOp3(v, OP_InitCoroutine, pItem->regReturn, 0, addrTop); - VdbeComment((v, "%s", pItem->pTab->zName)); + VdbeComment((v, "%!S", pItem)); pItem->addrFillSub = addrTop; sqlite3SelectDestInit(&dest, SRT_Coroutine, pItem->regReturn); - ExplainQueryPlan((pParse, 1, "CO-ROUTINE %u", pSub->selId)); + ExplainQueryPlan((pParse, 1, "CO-ROUTINE %!S", pItem)); sqlite3Select(pParse, pSub, &dest); pItem->pTab->nRowLogEst = pSub->nSelectRow; pItem->fg.viaCoroutine = 1; @@ -6072,46 +7684,67 @@ int sqlite3Select( sqlite3VdbeEndCoroutine(v, pItem->regReturn); sqlite3VdbeJumpHere(v, addrTop-1); sqlite3ClearTempRegCache(pParse); + }else if( pItem->fg.isCte && pItem->u2.pCteUse->addrM9e>0 ){ + /* This is a CTE for which materialization code has already been + ** generated. Invoke the subroutine to compute the materialization, + ** the make the pItem->iCursor be a copy of the ephemeral table that + ** holds the result of the materialization. */ + CteUse *pCteUse = pItem->u2.pCteUse; + sqlite3VdbeAddOp2(v, OP_Gosub, pCteUse->regRtn, pCteUse->addrM9e); + if( pItem->iCursor!=pCteUse->iCur ){ + sqlite3VdbeAddOp2(v, OP_OpenDup, pItem->iCursor, pCteUse->iCur); + VdbeComment((v, "%!S", pItem)); + } + pSub->nSelectRow = pCteUse->nRowEst; + }else if( (pPrior = isSelfJoinView(pTabList, pItem, 0, i))!=0 ){ + /* This view has already been materialized by a prior entry in + ** this same FROM clause. Reuse it. */ + if( pPrior->addrFillSub ){ + sqlite3VdbeAddOp2(v, OP_Gosub, pPrior->regReturn, pPrior->addrFillSub); + } + sqlite3VdbeAddOp2(v, OP_OpenDup, pItem->iCursor, pPrior->iCursor); + pSub->nSelectRow = pPrior->pSelect->nSelectRow; }else{ - /* Generate a subroutine that will fill an ephemeral table with - ** the content of this subquery. pItem->addrFillSub will point - ** to the address of the generated subroutine. pItem->regReturn - ** is a register allocated to hold the subroutine return address - */ + /* Materialize the view. If the view is not correlated, generate a + ** subroutine to do the materialization so that subsequent uses of + ** the same view can reuse the materialization. */ int topAddr; int onceAddr = 0; - int retAddr; - struct SrcList_item *pPrior; +#ifdef SQLITE_ENABLE_STMT_SCANSTATUS + int addrExplain; +#endif - testcase( pItem->addrFillSub==0 ); /* Ticket c52b09c7f38903b1311 */ pItem->regReturn = ++pParse->nMem; - topAddr = sqlite3VdbeAddOp2(v, OP_Integer, 0, pItem->regReturn); + topAddr = sqlite3VdbeAddOp0(v, OP_Goto); pItem->addrFillSub = topAddr+1; + pItem->fg.isMaterialized = 1; if( pItem->fg.isCorrelated==0 ){ /* If the subquery is not correlated and if we are not inside of ** a trigger, then we only need to compute the value of the subquery ** once. */ onceAddr = sqlite3VdbeAddOp0(v, OP_Once); VdbeCoverage(v); - VdbeComment((v, "materialize \"%s\"", pItem->pTab->zName)); - }else{ - VdbeNoopComment((v, "materialize \"%s\"", pItem->pTab->zName)); - } - pPrior = isSelfJoinView(pTabList, pItem); - if( pPrior ){ - sqlite3VdbeAddOp2(v, OP_OpenDup, pItem->iCursor, pPrior->iCursor); - assert( pPrior->pSelect!=0 ); - pSub->nSelectRow = pPrior->pSelect->nSelectRow; + VdbeComment((v, "materialize %!S", pItem)); }else{ - sqlite3SelectDestInit(&dest, SRT_EphemTab, pItem->iCursor); - ExplainQueryPlan((pParse, 1, "MATERIALIZE %u", pSub->selId)); - sqlite3Select(pParse, pSub, &dest); + VdbeNoopComment((v, "materialize %!S", pItem)); } + sqlite3SelectDestInit(&dest, SRT_EphemTab, pItem->iCursor); + + ExplainQueryPlan2(addrExplain, (pParse, 1, "MATERIALIZE %!S", pItem)); + sqlite3Select(pParse, pSub, &dest); pItem->pTab->nRowLogEst = pSub->nSelectRow; if( onceAddr ) sqlite3VdbeJumpHere(v, onceAddr); - retAddr = sqlite3VdbeAddOp1(v, OP_Return, pItem->regReturn); - VdbeComment((v, "end %s", pItem->pTab->zName)); - sqlite3VdbeChangeP1(v, topAddr, retAddr); + sqlite3VdbeAddOp2(v, OP_Return, pItem->regReturn, topAddr+1); + VdbeComment((v, "end %!S", pItem)); + sqlite3VdbeScanStatusRange(v, addrExplain, addrExplain, -1); + sqlite3VdbeJumpHere(v, topAddr); sqlite3ClearTempRegCache(pParse); + if( pItem->fg.isCte && pItem->fg.isCorrelated==0 ){ + CteUse *pCteUse = pItem->u2.pCteUse; + pCteUse->addrM9e = pItem->addrFillSub; + pCteUse->regRtn = pItem->regReturn; + pCteUse->iCur = pItem->iCursor; + pCteUse->nRowEst = pSub->nSelectRow; + } } if( db->mallocFailed ) goto select_end; pParse->nHeight -= sqlite3SelectExprHeight(p); @@ -6127,14 +7760,14 @@ int sqlite3Select( pHaving = p->pHaving; sDistinct.isTnct = (p->selFlags & SF_Distinct)!=0; -#if SELECTTRACE_ENABLED - if( sqlite3SelectTrace & 0x400 ){ - SELECTTRACE(0x400,pParse,p,("After all FROM-clause analysis:\n")); +#if TREETRACE_ENABLED + if( sqlite3TreeTrace & 0x8000 ){ + TREETRACE(0x8000,pParse,p,("After all FROM-clause analysis:\n")); sqlite3TreeViewSelect(0, p, 0); } #endif - /* If the query is DISTINCT with an ORDER BY but is not an aggregate, and + /* If the query is DISTINCT with an ORDER BY but is not an aggregate, and ** if the select-list is the same as the ORDER BY list, then this query ** can be rewritten as a GROUP BY. In other words, this: ** @@ -6144,12 +7777,12 @@ int sqlite3Select( ** ** SELECT xyz FROM ... GROUP BY xyz ORDER BY xyz ** - ** The second form is preferred as a single index (or temp-table) may be - ** used for both the ORDER BY and DISTINCT processing. As originally - ** written the query must use a temp-table for at least one of the ORDER + ** The second form is preferred as a single index (or temp-table) may be + ** used for both the ORDER BY and DISTINCT processing. As originally + ** written the query must use a temp-table for at least one of the ORDER ** BY and DISTINCT, and an index or separate temp-table for the other. */ - if( (p->selFlags & (SF_Distinct|SF_Aggregate))==SF_Distinct + if( (p->selFlags & (SF_Distinct|SF_Aggregate))==SF_Distinct && sqlite3ExprListCompare(sSort.pOrderBy, pEList, -1)==0 #ifndef SQLITE_OMIT_WINDOWFUNC && p->pWin==0 @@ -6162,10 +7795,11 @@ int sqlite3Select( ** the sDistinct.isTnct is still set. Hence, isTnct represents the ** original setting of the SF_Distinct flag, not the current setting */ assert( sDistinct.isTnct ); + sDistinct.isTnct = 2; -#if SELECTTRACE_ENABLED - if( sqlite3SelectTrace & 0x400 ){ - SELECTTRACE(0x400,pParse,p,("Transform DISTINCT into GROUP BY:\n")); +#if TREETRACE_ENABLED + if( sqlite3TreeTrace & 0x20000 ){ + TREETRACE(0x20000,pParse,p,("Transform DISTINCT into GROUP BY:\n")); sqlite3TreeViewSelect(0, p, 0); } #endif @@ -6197,6 +7831,18 @@ int sqlite3Select( */ if( pDest->eDest==SRT_EphemTab ){ sqlite3VdbeAddOp2(v, OP_OpenEphemeral, pDest->iSDParm, pEList->nExpr); + if( p->selFlags & SF_NestedFrom ){ + /* Delete or NULL-out result columns that will never be used */ + int ii; + for(ii=pEList->nExpr-1; ii>0 && pEList->a[ii].fg.bUsed==0; ii--){ + sqlite3ExprDelete(db, pEList->a[ii].pExpr); + sqlite3DbFree(db, pEList->a[ii].zEName); + pEList->nExpr--; + } + for(ii=0; ii<pEList->nExpr; ii++){ + if( pEList->a[ii].fg.bUsed==0 ) pEList->a[ii].pExpr->op = TK_NULL; + } + } } /* Set the limiter. @@ -6205,7 +7851,7 @@ int sqlite3Select( if( (p->selFlags & SF_FixedLimit)==0 ){ p->nSelectRow = 320; /* 4 billion rows */ } - computeLimitRegisters(pParse, p, iEnd); + if( p->pLimit ) computeLimitRegisters(pParse, p, iEnd); if( p->iLimit==0 && sSort.addrSortIndex>=0 ){ sqlite3VdbeChangeOpcode(v, sSort.addrSortIndex, OP_SorterOpen); sSort.sortFlags |= SORTFLAG_UseSorter; @@ -6239,9 +7885,9 @@ int sqlite3Select( /* Begin the database scan. */ - SELECTTRACE(1,pParse,p,("WhereBegin\n")); + TREETRACE(0x2,pParse,p,("WhereBegin\n")); pWInfo = sqlite3WhereBegin(pParse, pTabList, pWhere, sSort.pOrderBy, - p->pEList, wctrlFlags, p->nSelectRow); + p->pEList, p, wctrlFlags, p->nSelectRow); if( pWInfo==0 ) goto select_end; if( sqlite3WhereOutputRowCount(pWInfo) < p->nSelectRow ){ p->nSelectRow = sqlite3WhereOutputRowCount(pWInfo); @@ -6256,8 +7902,9 @@ int sqlite3Select( sSort.pOrderBy = 0; } } + TREETRACE(0x2,pParse,p,("WhereBegin returns\n")); - /* If sorting index that was created by a prior OP_OpenEphemeral + /* If sorting index that was created by a prior OP_OpenEphemeral ** instruction ended up not being needed, then change the OP_OpenEphemeral ** into an OP_Noop. */ @@ -6294,6 +7941,7 @@ int sqlite3Select( /* End the database scan loop. */ + TREETRACE(0x2,pParse,p,("WhereEnd\n")); sqlite3WhereEnd(pWInfo); } }else{ @@ -6329,8 +7977,8 @@ int sqlite3Select( if( p->nSelectRow>66 ) p->nSelectRow = 66; /* If there is both a GROUP BY and an ORDER BY clause and they are - ** identical, then it may be possible to disable the ORDER BY clause - ** on the grounds that the GROUP BY will cause elements to come out + ** identical, then it may be possible to disable the ORDER BY clause + ** on the grounds that the GROUP BY will cause elements to come out ** in the correct order. It also may not - the GROUP BY might use a ** database index that causes rows to be grouped together as required ** but not actually sorted. Either way, record the fact that the @@ -6340,12 +7988,13 @@ int sqlite3Select( int ii; /* The GROUP BY processing doesn't care whether rows are delivered in ** ASC or DESC order - only that each group is returned contiguously. - ** So set the ASC/DESC flags in the GROUP BY to match those in the - ** ORDER BY to maximize the chances of rows being delivered in an + ** So set the ASC/DESC flags in the GROUP BY to match those in the + ** ORDER BY to maximize the chances of rows being delivered in an ** order that makes the ORDER BY redundant. */ for(ii=0; ii<pGroupBy->nExpr; ii++){ - u8 sortFlags = sSort.pOrderBy->a[ii].sortFlags & KEYINFO_ORDER_DESC; - pGroupBy->a[ii].sortFlags = sortFlags; + u8 sortFlags; + sortFlags = sSort.pOrderBy->a[ii].fg.sortFlags & KEYINFO_ORDER_DESC; + pGroupBy->a[ii].fg.sortFlags = sortFlags; } if( sqlite3ExprListCompare(pGroupBy, sSort.pOrderBy, -1)==0 ){ orderByGrp = 1; @@ -6364,18 +8013,23 @@ int sqlite3Select( ** SELECT statement. */ pAggInfo = sqlite3DbMallocZero(db, sizeof(*pAggInfo) ); - if( pAggInfo==0 ){ + if( pAggInfo ){ + sqlite3ParserAddCleanup(pParse, + (void(*)(sqlite3*,void*))agginfoFree, pAggInfo); + testcase( pParse->earlyCleanup ); + } + if( db->mallocFailed ){ goto select_end; } - pAggInfo->pNext = pParse->pAggList; - pParse->pAggList = pAggInfo; pAggInfo->selId = p->selId; +#ifdef SQLITE_DEBUG + pAggInfo->pSelect = p; +#endif memset(&sNC, 0, sizeof(sNC)); sNC.pParse = pParse; sNC.pSrcList = pTabList; sNC.uNC.pAggInfo = pAggInfo; VVA_ONLY( sNC.ncFlags = NC_UAggInfo; ) - pAggInfo->mnReg = pParse->nMem+1; pAggInfo->nSortingColumn = pGroupBy ? pGroupBy->nExpr : 0; pAggInfo->pGroupBy = pGroupBy; sqlite3ExprAnalyzeAggList(&sNC, pEList); @@ -6396,36 +8050,17 @@ int sqlite3Select( }else{ minMaxFlag = WHERE_ORDERBY_NORMAL; } - for(i=0; i<pAggInfo->nFunc; i++){ - Expr *pExpr = pAggInfo->aFunc[i].pFExpr; - assert( !ExprHasProperty(pExpr, EP_xIsSelect) ); - sNC.ncFlags |= NC_InAggFunc; - sqlite3ExprAnalyzeAggList(&sNC, pExpr->x.pList); -#ifndef SQLITE_OMIT_WINDOWFUNC - assert( !IsWindowFunc(pExpr) ); - if( ExprHasProperty(pExpr, EP_WinFunc) ){ - sqlite3ExprAnalyzeAggregates(&sNC, pExpr->y.pWin->pFilter); - } -#endif - sNC.ncFlags &= ~NC_InAggFunc; - } - pAggInfo->mxReg = pParse->nMem; + analyzeAggFuncArgs(pAggInfo, &sNC); if( db->mallocFailed ) goto select_end; -#if SELECTTRACE_ENABLED - if( sqlite3SelectTrace & 0x400 ){ - int ii; - SELECTTRACE(0x400,pParse,p,("After aggregate analysis %p:\n", pAggInfo)); +#if TREETRACE_ENABLED + if( sqlite3TreeTrace & 0x20 ){ + TREETRACE(0x20,pParse,p,("After aggregate analysis %p:\n", pAggInfo)); sqlite3TreeViewSelect(0, p, 0); - for(ii=0; ii<pAggInfo->nColumn; ii++){ - sqlite3DebugPrintf("agg-column[%d] iMem=%d\n", - ii, pAggInfo->aCol[ii].iMem); - sqlite3TreeViewExpr(0, pAggInfo->aCol[ii].pCExpr, 0); - } - for(ii=0; ii<pAggInfo->nFunc; ii++){ - sqlite3DebugPrintf("agg-func[%d]: iMem=%d\n", - ii, pAggInfo->aFunc[ii].iMem); - sqlite3TreeViewExpr(0, pAggInfo->aFunc[ii].pFExpr, 0); + if( minMaxFlag ){ + sqlite3DebugPrintf("MIN/MAX Optimization (0x%02x) adds:\n", minMaxFlag); + sqlite3TreeViewExprList(0, pMinMaxOrderBy, 0, "ORDERBY"); } + printAggInfo(pAggInfo); } #endif @@ -6435,7 +8070,7 @@ int sqlite3Select( */ if( pGroupBy ){ KeyInfo *pKeyInfo; /* Keying information for the group by clause */ - int addr1; /* A-vs-B comparision jump */ + int addr1; /* A-vs-B comparison 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 */ @@ -6443,17 +8078,33 @@ int sqlite3Select( int addrSortingIdx; /* The OP_OpenEphemeral for the sorting index */ int addrReset; /* Subroutine for resetting the accumulator */ int regReset; /* Return address register for reset subroutine */ + ExprList *pDistinct = 0; + u16 distFlag = 0; + int eDist = WHERE_DISTINCT_NOOP; + + if( pAggInfo->nFunc==1 + && pAggInfo->aFunc[0].iDistinct>=0 + && ALWAYS(pAggInfo->aFunc[0].pFExpr!=0) + && ALWAYS(ExprUseXList(pAggInfo->aFunc[0].pFExpr)) + && pAggInfo->aFunc[0].pFExpr->x.pList!=0 + ){ + Expr *pExpr = pAggInfo->aFunc[0].pFExpr->x.pList->a[0].pExpr; + pExpr = sqlite3ExprDup(db, pExpr, 0); + pDistinct = sqlite3ExprListDup(db, pGroupBy, 0); + pDistinct = sqlite3ExprListAppend(pParse, pDistinct, pExpr); + distFlag = pDistinct ? (WHERE_WANT_DISTINCT|WHERE_AGG_DISTINCT) : 0; + } /* 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 ** that we do not need it after all, the OP_SorterOpen instruction - ** will be converted into a Noop. + ** will be converted into a Noop. */ pAggInfo->sortingIdx = pParse->nTab++; pKeyInfo = sqlite3KeyInfoFromExprList(pParse, pGroupBy, 0, pAggInfo->nColumn); - addrSortingIdx = sqlite3VdbeAddOp4(v, OP_SorterOpen, - pAggInfo->sortingIdx, pAggInfo->nSortingColumn, + addrSortingIdx = sqlite3VdbeAddOp4(v, OP_SorterOpen, + pAggInfo->sortingIdx, pAggInfo->nSortingColumn, 0, (char*)pKeyInfo, P4_KEYINFO); /* Initialize memory locations used by GROUP BY aggregate processing @@ -6478,11 +8129,21 @@ int sqlite3Select( ** in the right order to begin with. */ sqlite3VdbeAddOp2(v, OP_Gosub, regReset, addrReset); - SELECTTRACE(1,pParse,p,("WhereBegin\n")); - pWInfo = sqlite3WhereBegin(pParse, pTabList, pWhere, pGroupBy, 0, - WHERE_GROUPBY | (orderByGrp ? WHERE_SORTBYGROUP : 0), 0 + TREETRACE(0x2,pParse,p,("WhereBegin\n")); + pWInfo = sqlite3WhereBegin(pParse, pTabList, pWhere, pGroupBy, pDistinct, + p, (sDistinct.isTnct==2 ? WHERE_DISTINCTBY : WHERE_GROUPBY) + | (orderByGrp ? WHERE_SORTBYGROUP : 0) | distFlag, 0 ); - if( pWInfo==0 ) goto select_end; + if( pWInfo==0 ){ + sqlite3ExprListDelete(db, pDistinct); + goto select_end; + } + if( pParse->pIdxEpr ){ + optimizeAggregateUseOfIndexedExpr(pParse, p, pAggInfo, &sNC); + } + assignAggregateRegisters(pParse, pAggInfo); + eDist = sqlite3WhereIsDistinct(pWInfo); + TREETRACE(0x2,pParse,p,("WhereBegin returns\n")); if( sqlite3WhereIsOrdered(pWInfo)==pGroupBy->nExpr ){ /* The optimizer is able to deliver rows in group by order so ** we do not have to sort. The OP_OpenEphemeral table will be @@ -6500,9 +8161,13 @@ int sqlite3Select( int nCol; int nGroupBy; - explainTempTable(pParse, +#ifdef SQLITE_ENABLE_STMT_SCANSTATUS + int addrExp; /* Address of OP_Explain instruction */ +#endif + ExplainQueryPlan2(addrExp, (pParse, 0, "USE TEMP B-TREE FOR %s", (sDistinct.isTnct && (p->selFlags&SF_Distinct)==0) ? - "DISTINCT" : "GROUP BY"); + "DISTINCT" : "GROUP BY" + )); groupBySort = 1; nGroupBy = pGroupBy->nExpr; @@ -6517,27 +8182,50 @@ int sqlite3Select( regBase = sqlite3GetTempRange(pParse, nCol); sqlite3ExprCodeExprList(pParse, pGroupBy, regBase, 0, 0); j = nGroupBy; + pAggInfo->directMode = 1; for(i=0; i<pAggInfo->nColumn; i++){ struct AggInfo_col *pCol = &pAggInfo->aCol[i]; if( pCol->iSorterColumn>=j ){ - int r1 = j + regBase; - sqlite3ExprCodeGetColumnOfTable(v, - pCol->pTab, pCol->iTable, pCol->iColumn, r1); + sqlite3ExprCode(pParse, pCol->pCExpr, j + regBase); j++; } } + pAggInfo->directMode = 0; regRecord = sqlite3GetTempReg(pParse); + sqlite3VdbeScanStatusCounters(v, addrExp, 0, sqlite3VdbeCurrentAddr(v)); sqlite3VdbeAddOp3(v, OP_MakeRecord, regBase, nCol, regRecord); sqlite3VdbeAddOp2(v, OP_SorterInsert, pAggInfo->sortingIdx, regRecord); + sqlite3VdbeScanStatusRange(v, addrExp, sqlite3VdbeCurrentAddr(v)-2, -1); sqlite3ReleaseTempReg(pParse, regRecord); sqlite3ReleaseTempRange(pParse, regBase, nCol); + TREETRACE(0x2,pParse,p,("WhereEnd\n")); sqlite3WhereEnd(pWInfo); pAggInfo->sortingIdxPTab = sortPTab = pParse->nTab++; sortOut = sqlite3GetTempReg(pParse); + sqlite3VdbeScanStatusCounters(v, addrExp, sqlite3VdbeCurrentAddr(v), 0); sqlite3VdbeAddOp3(v, OP_OpenPseudo, sortPTab, sortOut, nCol); sqlite3VdbeAddOp2(v, OP_SorterSort, pAggInfo->sortingIdx, addrEnd); VdbeComment((v, "GROUP BY sort")); VdbeCoverage(v); pAggInfo->useSortingIdx = 1; + sqlite3VdbeScanStatusRange(v, addrExp, -1, sortPTab); + sqlite3VdbeScanStatusRange(v, addrExp, -1, pAggInfo->sortingIdx); + } + + /* If there are entries in pAgggInfo->aFunc[] that contain subexpressions + ** that are indexed (and that were previously identified and tagged + ** in optimizeAggregateUseOfIndexedExpr()) then those subexpressions + ** must now be converted into a TK_AGG_COLUMN node so that the value + ** is correctly pulled from the index rather than being recomputed. */ + if( pParse->pIdxEpr ){ + aggregateConvertIndexedExprRefToColumn(pAggInfo); +#if TREETRACE_ENABLED + if( sqlite3TreeTrace & 0x20 ){ + TREETRACE(0x20, pParse, p, + ("AggInfo function expressions converted to reference index\n")); + sqlite3TreeViewSelect(0, p, 0); + printAggInfo(pAggInfo); + } +#endif } /* If the index or temporary table used by the GROUP BY sort @@ -6545,9 +8233,9 @@ int sqlite3Select( ** clause, cancel the ephemeral table open coded earlier. ** ** This is an optimization - the correct answer should result regardless. - ** Use the SQLITE_GroupByOrder flag with SQLITE_TESTCTRL_OPTIMIZER to + ** Use the SQLITE_GroupByOrder flag with SQLITE_TESTCTRL_OPTIMIZER to ** disable this optimization for testing purposes. */ - if( orderByGrp && OptimizationEnabled(db, SQLITE_GroupByOrder) + if( orderByGrp && OptimizationEnabled(db, SQLITE_GroupByOrder) && (groupBySort || sqlite3WhereIsSorted(pWInfo)) ){ sSort.pOrderBy = 0; @@ -6598,19 +8286,21 @@ int sqlite3Select( ** the current row */ sqlite3VdbeJumpHere(v, addr1); - updateAccumulator(pParse, iUseFlag, pAggInfo); + updateAccumulator(pParse, iUseFlag, pAggInfo, eDist); sqlite3VdbeAddOp2(v, OP_Integer, 1, iUseFlag); VdbeComment((v, "indicate data in accumulator")); /* End of the loop */ if( groupBySort ){ - sqlite3VdbeAddOp2(v, OP_SorterNext, pAggInfo->sortingIdx, addrTopOfLoop); + sqlite3VdbeAddOp2(v, OP_SorterNext, pAggInfo->sortingIdx,addrTopOfLoop); VdbeCoverage(v); }else{ + TREETRACE(0x2,pParse,p,("WhereEnd\n")); sqlite3WhereEnd(pWInfo); sqlite3VdbeChangeToNoop(v, addrSortingIdx); } + sqlite3ExprListDelete(db, pDistinct); /* Output the final row of result */ @@ -6653,7 +8343,11 @@ int sqlite3Select( sqlite3VdbeAddOp2(v, OP_Integer, 0, iUseFlag); VdbeComment((v, "indicate accumulator empty")); sqlite3VdbeAddOp1(v, OP_Return, regReset); - + + if( distFlag!=0 && eDist!=WHERE_DISTINCT_NOOP ){ + struct AggInfo_func *pF = &pAggInfo->aFunc[0]; + fixDistinctOpenEph(pParse, eDist, pF->iDistinct, pF->iDistAddr); + } } /* endif pGroupBy. Begin aggregate queries without GROUP BY: */ else { Table *pTab; @@ -6676,7 +8370,7 @@ int sqlite3Select( 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 */ + Pgno iRoot = pTab->tnum; /* Root page of scanned b-tree */ sqlite3CodeVerifySchema(pParse, iDb); sqlite3TableLock(pParse, iDb, pTab->tnum, 0, pTab->zName); @@ -6687,7 +8381,7 @@ int sqlite3Select( ** ** (2013-10-03) Do not count the entries in a partial index. ** - ** In practice the KeyInfo structure will not be used. It is only + ** In practice the KeyInfo structure will not be used. It is only ** passed to keep OP_OpenRead happy. */ if( !HasRowid(pTab) ) pBest = sqlite3PrimaryKeyIndex(pTab); @@ -6708,15 +8402,19 @@ int sqlite3Select( } /* Open a read-only cursor, execute the OP_Count, close the cursor. */ - sqlite3VdbeAddOp4Int(v, OP_OpenRead, iCsr, iRoot, iDb, 1); + sqlite3VdbeAddOp4Int(v, OP_OpenRead, iCsr, (int)iRoot, iDb, 1); if( pKeyInfo ){ sqlite3VdbeChangeP4(v, -1, (char *)pKeyInfo, P4_KEYINFO); } - sqlite3VdbeAddOp2(v, OP_Count, iCsr, pAggInfo->aFunc[0].iMem); + assignAggregateRegisters(pParse, pAggInfo); + sqlite3VdbeAddOp2(v, OP_Count, iCsr, AggInfoFuncReg(pAggInfo,0)); sqlite3VdbeAddOp1(v, OP_Close, iCsr); explainSimpleCount(pParse, pTab, pBest); }else{ int regAcc = 0; /* "populate accumulators" flag */ + ExprList *pDistinct = 0; + u16 distFlag = 0; + int eDist; /* If there are accumulator registers but no min() or max() functions ** without FILTER clauses, allocate register regAcc. Register regAcc @@ -6725,7 +8423,7 @@ int sqlite3Select( ** that the accumulator registers are (a) updated only once if ** there are no min() or max functions or (b) always updated for the ** first row visited by the aggregate, so that they are updated at - ** least once even if the FILTER clause means the min() or max() + ** least once even if the FILTER clause means the min() or max() ** function visits zero rows. */ if( pAggInfo->nAccumulator ){ for(i=0; i<pAggInfo->nFunc; i++){ @@ -6740,7 +8438,12 @@ int sqlite3Select( regAcc = ++pParse->nMem; sqlite3VdbeAddOp2(v, OP_Integer, 0, regAcc); } + }else if( pAggInfo->nFunc==1 && pAggInfo->aFunc[0].iDistinct>=0 ){ + assert( ExprUseXList(pAggInfo->aFunc[0].pFExpr) ); + pDistinct = pAggInfo->aFunc[0].pFExpr->x.pList; + distFlag = pDistinct ? (WHERE_WANT_DISTINCT|WHERE_AGG_DISTINCT) : 0; } + assignAggregateRegisters(pParse, pAggInfo); /* This case runs if the aggregate has no GROUP BY clause. The ** processing is much simpler since there is only a single row @@ -6757,30 +8460,38 @@ int sqlite3Select( assert( minMaxFlag==WHERE_ORDERBY_NORMAL || pMinMaxOrderBy!=0 ); assert( pMinMaxOrderBy==0 || pMinMaxOrderBy->nExpr==1 ); - SELECTTRACE(1,pParse,p,("WhereBegin\n")); + TREETRACE(0x2,pParse,p,("WhereBegin\n")); pWInfo = sqlite3WhereBegin(pParse, pTabList, pWhere, pMinMaxOrderBy, - 0, minMaxFlag, 0); + pDistinct, p, minMaxFlag|distFlag, 0); if( pWInfo==0 ){ goto select_end; } - updateAccumulator(pParse, regAcc, pAggInfo); + TREETRACE(0x2,pParse,p,("WhereBegin returns\n")); + eDist = sqlite3WhereIsDistinct(pWInfo); + updateAccumulator(pParse, regAcc, pAggInfo, eDist); + if( eDist!=WHERE_DISTINCT_NOOP ){ + struct AggInfo_func *pF = pAggInfo->aFunc; + if( pF ){ + fixDistinctOpenEph(pParse, eDist, pF->iDistinct, pF->iDistAddr); + } + } + if( regAcc ) sqlite3VdbeAddOp2(v, OP_Integer, 1, regAcc); - if( sqlite3WhereIsOrdered(pWInfo)>0 ){ - sqlite3VdbeGoto(v, sqlite3WhereBreakLabel(pWInfo)); - VdbeComment((v, "%s() by index", - (minMaxFlag==WHERE_ORDERBY_MIN?"min":"max"))); + if( minMaxFlag ){ + sqlite3WhereMinMaxOptEarlyOut(v, pWInfo); } + TREETRACE(0x2,pParse,p,("WhereEnd\n")); sqlite3WhereEnd(pWInfo); finalizeAggFunctions(pParse, pAggInfo); } sSort.pOrderBy = 0; sqlite3ExprIfFalse(pParse, pHaving, addrEnd, SQLITE_JUMPIFNULL); - selectInnerLoop(pParse, p, -1, 0, 0, + selectInnerLoop(pParse, p, -1, 0, 0, pDest, addrEnd, addrEnd); } sqlite3VdbeResolveLabel(v, addrEnd); - + } /* endif aggregate query */ if( sDistinct.eTnctType==WHERE_DISTINCT_UNORDERED ){ @@ -6791,8 +8502,6 @@ int sqlite3Select( ** and send them to the callback one by one. */ if( sSort.pOrderBy ){ - explainTempTable(pParse, - sSort.nOBSat>0 ? "RIGHT PART OF ORDER BY":"ORDER BY"); assert( p->pEList==pEList ); generateSortTail(pParse, p, &sSort, pEList->nExpr, pDest); } @@ -6809,29 +8518,29 @@ int sqlite3Select( ** successful coding of the SELECT. */ select_end: + assert( db->mallocFailed==0 || db->mallocFailed==1 ); + assert( db->mallocFailed==0 || pParse->nErr!=0 ); sqlite3ExprListDelete(db, pMinMaxOrderBy); #ifdef SQLITE_DEBUG if( pAggInfo && !db->mallocFailed ){ for(i=0; i<pAggInfo->nColumn; i++){ Expr *pExpr = pAggInfo->aCol[i].pCExpr; - assert( pExpr!=0 || db->mallocFailed ); if( pExpr==0 ) continue; assert( pExpr->pAggInfo==pAggInfo ); assert( pExpr->iAgg==i ); } for(i=0; i<pAggInfo->nFunc; i++){ Expr *pExpr = pAggInfo->aFunc[i].pFExpr; - assert( pExpr!=0 || db->mallocFailed ); - if( pExpr==0 ) continue; + assert( pExpr!=0 ); assert( pExpr->pAggInfo==pAggInfo ); assert( pExpr->iAgg==i ); } } #endif -#if SELECTTRACE_ENABLED - SELECTTRACE(0x1,pParse,p,("end processing\n")); - if( (sqlite3SelectTrace & 0x2000)!=0 && ExplainQueryPlanParent(pParse)==0 ){ +#if TREETRACE_ENABLED + TREETRACE(0x1,pParse,p,("end processing\n")); + if( (sqlite3TreeTrace & 0x40000)!=0 && ExplainQueryPlanParent(pParse)==0 ){ sqlite3TreeViewSelect(0, p, 0); } #endif |