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Diffstat (limited to 'lib/libsqlite3/src/resolve.c')
| -rw-r--r-- | lib/libsqlite3/src/resolve.c | 1494 |
1 files changed, 0 insertions, 1494 deletions
diff --git a/lib/libsqlite3/src/resolve.c b/lib/libsqlite3/src/resolve.c deleted file mode 100644 index ac1706b5957..00000000000 --- a/lib/libsqlite3/src/resolve.c +++ /dev/null @@ -1,1494 +0,0 @@ -/* -** 2008 August 18 -** -** The author disclaims copyright to this source code. In place of -** a legal notice, here is a blessing: -** -** May you do good and not evil. -** May you find forgiveness for yourself and forgive others. -** May you share freely, never taking more than you give. -** -************************************************************************* -** -** This file contains routines used for walking the parser tree and -** resolve all identifiers by associating them with a particular -** table and column. -*/ -#include "sqliteInt.h" -#include <stdlib.h> -#include <string.h> - -/* -** Walk the expression tree pExpr and increase the aggregate function -** depth (the Expr.op2 field) by N on every TK_AGG_FUNCTION node. -** This needs to occur when copying a TK_AGG_FUNCTION node from an -** outer query into an inner subquery. -** -** incrAggFunctionDepth(pExpr,n) is the main routine. incrAggDepth(..) -** is a helper function - a callback for the tree walker. -*/ -static int incrAggDepth(Walker *pWalker, Expr *pExpr){ - if( pExpr->op==TK_AGG_FUNCTION ) pExpr->op2 += pWalker->u.n; - return WRC_Continue; -} -static void incrAggFunctionDepth(Expr *pExpr, int N){ - if( N>0 ){ - Walker w; - memset(&w, 0, sizeof(w)); - w.xExprCallback = incrAggDepth; - w.u.n = N; - sqlite3WalkExpr(&w, pExpr); - } -} - -/* -** Turn the pExpr expression into an alias for the iCol-th column of the -** result set in pEList. -** -** If the reference is followed by a COLLATE operator, then make sure -** the COLLATE operator is preserved. For example: -** -** SELECT a+b, c+d FROM t1 ORDER BY 1 COLLATE nocase; -** -** Should be transformed into: -** -** SELECT a+b, c+d FROM t1 ORDER BY (a+b) COLLATE nocase; -** -** The nSubquery parameter specifies how many levels of subquery the -** alias is removed from the original expression. The usual value is -** zero but it might be more if the alias is contained within a subquery -** of the original expression. The Expr.op2 field of TK_AGG_FUNCTION -** structures must be increased by the nSubquery amount. -*/ -static void resolveAlias( - Parse *pParse, /* Parsing context */ - ExprList *pEList, /* A result set */ - int iCol, /* A column in the result set. 0..pEList->nExpr-1 */ - Expr *pExpr, /* Transform this into an alias to the result set */ - const char *zType, /* "GROUP" or "ORDER" or "" */ - int nSubquery /* Number of subqueries that the label is moving */ -){ - Expr *pOrig; /* The iCol-th column of the result set */ - Expr *pDup; /* Copy of pOrig */ - sqlite3 *db; /* The database connection */ - - assert( iCol>=0 && iCol<pEList->nExpr ); - pOrig = pEList->a[iCol].pExpr; - assert( pOrig!=0 ); - db = pParse->db; - pDup = sqlite3ExprDup(db, pOrig, 0); - if( pDup==0 ) return; - if( zType[0]!='G' ) incrAggFunctionDepth(pDup, nSubquery); - if( pExpr->op==TK_COLLATE ){ - pDup = sqlite3ExprAddCollateString(pParse, pDup, pExpr->u.zToken); - } - ExprSetProperty(pDup, EP_Alias); - - /* Before calling sqlite3ExprDelete(), set the EP_Static flag. This - ** prevents ExprDelete() from deleting the Expr structure itself, - ** allowing it to be repopulated by the memcpy() on the following line. - ** The pExpr->u.zToken might point into memory that will be freed by the - ** sqlite3DbFree(db, pDup) on the last line of this block, so be sure to - ** make a copy of the token before doing the sqlite3DbFree(). - */ - ExprSetProperty(pExpr, EP_Static); - sqlite3ExprDelete(db, pExpr); - memcpy(pExpr, pDup, sizeof(*pExpr)); - if( !ExprHasProperty(pExpr, EP_IntValue) && pExpr->u.zToken!=0 ){ - assert( (pExpr->flags & (EP_Reduced|EP_TokenOnly))==0 ); - pExpr->u.zToken = sqlite3DbStrDup(db, pExpr->u.zToken); - pExpr->flags |= EP_MemToken; - } - sqlite3DbFree(db, pDup); -} - - -/* -** Return TRUE if the name zCol occurs anywhere in the USING clause. -** -** Return FALSE if the USING clause is NULL or if it does not contain -** zCol. -*/ -static int nameInUsingClause(IdList *pUsing, const char *zCol){ - if( pUsing ){ - int k; - for(k=0; k<pUsing->nId; k++){ - if( sqlite3StrICmp(pUsing->a[k].zName, zCol)==0 ) return 1; - } - } - return 0; -} - -/* -** Subqueries stores the original database, table and column names for their -** result sets in ExprList.a[].zSpan, in the form "DATABASE.TABLE.COLUMN". -** Check to see if the zSpan given to this routine matches the zDb, zTab, -** and zCol. If any of zDb, zTab, and zCol are NULL then those fields will -** match anything. -*/ -int sqlite3MatchSpanName( - const char *zSpan, - const char *zCol, - const char *zTab, - const char *zDb -){ - int n; - for(n=0; ALWAYS(zSpan[n]) && zSpan[n]!='.'; n++){} - if( zDb && (sqlite3StrNICmp(zSpan, zDb, n)!=0 || zDb[n]!=0) ){ - return 0; - } - zSpan += n+1; - for(n=0; ALWAYS(zSpan[n]) && zSpan[n]!='.'; n++){} - if( zTab && (sqlite3StrNICmp(zSpan, zTab, n)!=0 || zTab[n]!=0) ){ - return 0; - } - zSpan += n+1; - if( zCol && sqlite3StrICmp(zSpan, zCol)!=0 ){ - return 0; - } - return 1; -} - -/* -** Given the name of a column of the form X.Y.Z or Y.Z or just Z, look up -** that name in the set of source tables in pSrcList and make the pExpr -** expression node refer back to that source column. The following changes -** are made to pExpr: -** -** pExpr->iDb Set the index in db->aDb[] of the database X -** (even if X is implied). -** pExpr->iTable Set to the cursor number for the table obtained -** from pSrcList. -** pExpr->pTab Points to the Table structure of X.Y (even if -** X and/or Y are implied.) -** pExpr->iColumn Set to the column number within the table. -** pExpr->op Set to TK_COLUMN. -** pExpr->pLeft Any expression this points to is deleted -** pExpr->pRight Any expression this points to is deleted. -** -** The zDb variable is the name of the database (the "X"). This value may be -** NULL meaning that name is of the form Y.Z or Z. Any available database -** can be used. The zTable variable is the name of the table (the "Y"). This -** value can be NULL if zDb is also NULL. If zTable is NULL it -** means that the form of the name is Z and that columns from any table -** can be used. -** -** If the name cannot be resolved unambiguously, leave an error message -** in pParse and return WRC_Abort. Return WRC_Prune on success. -*/ -static int lookupName( - Parse *pParse, /* The parsing context */ - const char *zDb, /* Name of the database containing table, or NULL */ - const char *zTab, /* Name of table containing column, or NULL */ - const char *zCol, /* Name of the column. */ - NameContext *pNC, /* The name context used to resolve the name */ - Expr *pExpr /* Make this EXPR node point to the selected column */ -){ - int i, j; /* Loop counters */ - int cnt = 0; /* Number of matching column names */ - int cntTab = 0; /* Number of matching table names */ - int nSubquery = 0; /* How many levels of subquery */ - sqlite3 *db = pParse->db; /* The database connection */ - struct SrcList_item *pItem; /* Use for looping over pSrcList items */ - struct SrcList_item *pMatch = 0; /* The matching pSrcList item */ - NameContext *pTopNC = pNC; /* First namecontext in the list */ - Schema *pSchema = 0; /* Schema of the expression */ - int isTrigger = 0; /* True if resolved to a trigger column */ - Table *pTab = 0; /* Table hold the row */ - Column *pCol; /* A column of pTab */ - - assert( pNC ); /* the name context cannot be NULL. */ - assert( zCol ); /* The Z in X.Y.Z cannot be NULL */ - assert( !ExprHasProperty(pExpr, EP_TokenOnly|EP_Reduced) ); - - /* Initialize the node to no-match */ - pExpr->iTable = -1; - pExpr->pTab = 0; - ExprSetVVAProperty(pExpr, EP_NoReduce); - - /* Translate the schema name in zDb into a pointer to the corresponding - ** schema. If not found, pSchema will remain NULL and nothing will match - ** resulting in an appropriate error message toward the end of this routine - */ - if( zDb ){ - testcase( pNC->ncFlags & NC_PartIdx ); - testcase( pNC->ncFlags & NC_IsCheck ); - if( (pNC->ncFlags & (NC_PartIdx|NC_IsCheck))!=0 ){ - /* Silently ignore database qualifiers inside CHECK constraints and - ** partial indices. Do not raise errors because that might break - ** legacy and because it does not hurt anything to just ignore the - ** database name. */ - zDb = 0; - }else{ - for(i=0; i<db->nDb; i++){ - assert( db->aDb[i].zName ); - if( sqlite3StrICmp(db->aDb[i].zName,zDb)==0 ){ - pSchema = db->aDb[i].pSchema; - break; - } - } - } - } - - /* Start at the inner-most context and move outward until a match is found */ - while( pNC && cnt==0 ){ - ExprList *pEList; - SrcList *pSrcList = pNC->pSrcList; - - if( pSrcList ){ - for(i=0, pItem=pSrcList->a; i<pSrcList->nSrc; i++, pItem++){ - pTab = pItem->pTab; - assert( pTab!=0 && pTab->zName!=0 ); - assert( pTab->nCol>0 ); - if( pItem->pSelect && (pItem->pSelect->selFlags & SF_NestedFrom)!=0 ){ - int hit = 0; - pEList = pItem->pSelect->pEList; - for(j=0; j<pEList->nExpr; j++){ - if( sqlite3MatchSpanName(pEList->a[j].zSpan, zCol, zTab, zDb) ){ - cnt++; - cntTab = 2; - pMatch = pItem; - pExpr->iColumn = j; - hit = 1; - } - } - if( hit || zTab==0 ) continue; - } - if( zDb && pTab->pSchema!=pSchema ){ - continue; - } - if( zTab ){ - const char *zTabName = pItem->zAlias ? pItem->zAlias : pTab->zName; - assert( zTabName!=0 ); - if( sqlite3StrICmp(zTabName, zTab)!=0 ){ - continue; - } - } - if( 0==(cntTab++) ){ - pMatch = pItem; - } - for(j=0, pCol=pTab->aCol; j<pTab->nCol; j++, pCol++){ - if( sqlite3StrICmp(pCol->zName, zCol)==0 ){ - /* If there has been exactly one prior match and this match - ** is for the right-hand table of a NATURAL JOIN or is in a - ** USING clause, then skip this match. - */ - if( cnt==1 ){ - if( pItem->fg.jointype & JT_NATURAL ) continue; - if( nameInUsingClause(pItem->pUsing, zCol) ) continue; - } - cnt++; - pMatch = pItem; - /* Substitute the rowid (column -1) for the INTEGER PRIMARY KEY */ - pExpr->iColumn = j==pTab->iPKey ? -1 : (i16)j; - break; - } - } - } - if( pMatch ){ - pExpr->iTable = pMatch->iCursor; - pExpr->pTab = pMatch->pTab; - /* RIGHT JOIN not (yet) supported */ - assert( (pMatch->fg.jointype & JT_RIGHT)==0 ); - if( (pMatch->fg.jointype & JT_LEFT)!=0 ){ - ExprSetProperty(pExpr, EP_CanBeNull); - } - pSchema = pExpr->pTab->pSchema; - } - } /* if( pSrcList ) */ - -#ifndef SQLITE_OMIT_TRIGGER - /* If we have not already resolved the name, then maybe - ** it is a new.* or old.* trigger argument reference - */ - if( zDb==0 && zTab!=0 && cntTab==0 && pParse->pTriggerTab!=0 ){ - int op = pParse->eTriggerOp; - assert( op==TK_DELETE || op==TK_UPDATE || op==TK_INSERT ); - if( op!=TK_DELETE && sqlite3StrICmp("new",zTab) == 0 ){ - pExpr->iTable = 1; - pTab = pParse->pTriggerTab; - }else if( op!=TK_INSERT && sqlite3StrICmp("old",zTab)==0 ){ - pExpr->iTable = 0; - pTab = pParse->pTriggerTab; - }else{ - pTab = 0; - } - - if( pTab ){ - int iCol; - pSchema = pTab->pSchema; - cntTab++; - for(iCol=0, pCol=pTab->aCol; iCol<pTab->nCol; iCol++, pCol++){ - if( sqlite3StrICmp(pCol->zName, zCol)==0 ){ - if( iCol==pTab->iPKey ){ - iCol = -1; - } - break; - } - } - if( iCol>=pTab->nCol && sqlite3IsRowid(zCol) && VisibleRowid(pTab) ){ - /* IMP: R-51414-32910 */ - /* IMP: R-44911-55124 */ - iCol = -1; - } - if( iCol<pTab->nCol ){ - cnt++; - if( iCol<0 ){ - pExpr->affinity = SQLITE_AFF_INTEGER; - }else if( pExpr->iTable==0 ){ - testcase( iCol==31 ); - testcase( iCol==32 ); - pParse->oldmask |= (iCol>=32 ? 0xffffffff : (((u32)1)<<iCol)); - }else{ - testcase( iCol==31 ); - testcase( iCol==32 ); - pParse->newmask |= (iCol>=32 ? 0xffffffff : (((u32)1)<<iCol)); - } - pExpr->iColumn = (i16)iCol; - pExpr->pTab = pTab; - isTrigger = 1; - } - } - } -#endif /* !defined(SQLITE_OMIT_TRIGGER) */ - - /* - ** Perhaps the name is a reference to the ROWID - */ - if( cnt==0 - && cntTab==1 - && pMatch - && (pNC->ncFlags & NC_IdxExpr)==0 - && sqlite3IsRowid(zCol) - && VisibleRowid(pMatch->pTab) - ){ - cnt = 1; - pExpr->iColumn = -1; /* IMP: R-44911-55124 */ - pExpr->affinity = SQLITE_AFF_INTEGER; - } - - /* - ** If the input is of the form Z (not Y.Z or X.Y.Z) then the name Z - ** might refer to an result-set alias. This happens, for example, when - ** we are resolving names in the WHERE clause of the following command: - ** - ** SELECT a+b AS x FROM table WHERE x<10; - ** - ** In cases like this, replace pExpr with a copy of the expression that - ** forms the result set entry ("a+b" in the example) and return immediately. - ** Note that the expression in the result set should have already been - ** resolved by the time the WHERE clause is resolved. - ** - ** The ability to use an output result-set column in the WHERE, GROUP BY, - ** or HAVING clauses, or as part of a larger expression in the ORDER BY - ** clause is not standard SQL. This is a (goofy) SQLite extension, that - ** is supported for backwards compatibility only. Hence, we issue a warning - ** on sqlite3_log() whenever the capability is used. - */ - if( (pEList = pNC->pEList)!=0 - && zTab==0 - && cnt==0 - ){ - for(j=0; j<pEList->nExpr; j++){ - char *zAs = pEList->a[j].zName; - if( zAs!=0 && sqlite3StrICmp(zAs, zCol)==0 ){ - Expr *pOrig; - assert( pExpr->pLeft==0 && pExpr->pRight==0 ); - assert( pExpr->x.pList==0 ); - assert( pExpr->x.pSelect==0 ); - pOrig = pEList->a[j].pExpr; - if( (pNC->ncFlags&NC_AllowAgg)==0 && ExprHasProperty(pOrig, EP_Agg) ){ - sqlite3ErrorMsg(pParse, "misuse of aliased aggregate %s", zAs); - return WRC_Abort; - } - resolveAlias(pParse, pEList, j, pExpr, "", nSubquery); - cnt = 1; - pMatch = 0; - assert( zTab==0 && zDb==0 ); - goto lookupname_end; - } - } - } - - /* Advance to the next name context. The loop will exit when either - ** we have a match (cnt>0) or when we run out of name contexts. - */ - if( cnt==0 ){ - pNC = pNC->pNext; - nSubquery++; - } - } - - /* - ** If X and Y are NULL (in other words if only the column name Z is - ** supplied) and the value of Z is enclosed in double-quotes, then - ** Z is a string literal if it doesn't match any column names. In that - ** case, we need to return right away and not make any changes to - ** pExpr. - ** - ** Because no reference was made to outer contexts, the pNC->nRef - ** fields are not changed in any context. - */ - if( cnt==0 && zTab==0 && ExprHasProperty(pExpr,EP_DblQuoted) ){ - pExpr->op = TK_STRING; - pExpr->pTab = 0; - return WRC_Prune; - } - - /* - ** cnt==0 means there was not match. cnt>1 means there were two or - ** more matches. Either way, we have an error. - */ - if( cnt!=1 ){ - const char *zErr; - zErr = cnt==0 ? "no such column" : "ambiguous column name"; - if( zDb ){ - sqlite3ErrorMsg(pParse, "%s: %s.%s.%s", zErr, zDb, zTab, zCol); - }else if( zTab ){ - sqlite3ErrorMsg(pParse, "%s: %s.%s", zErr, zTab, zCol); - }else{ - sqlite3ErrorMsg(pParse, "%s: %s", zErr, zCol); - } - pParse->checkSchema = 1; - pTopNC->nErr++; - } - - /* If a column from a table in pSrcList is referenced, then record - ** this fact in the pSrcList.a[].colUsed bitmask. Column 0 causes - ** bit 0 to be set. Column 1 sets bit 1. And so forth. If the - ** column number is greater than the number of bits in the bitmask - ** then set the high-order bit of the bitmask. - */ - if( pExpr->iColumn>=0 && pMatch!=0 ){ - int n = pExpr->iColumn; - testcase( n==BMS-1 ); - if( n>=BMS ){ - n = BMS-1; - } - assert( pMatch->iCursor==pExpr->iTable ); - pMatch->colUsed |= ((Bitmask)1)<<n; - } - - /* Clean up and return - */ - sqlite3ExprDelete(db, pExpr->pLeft); - pExpr->pLeft = 0; - sqlite3ExprDelete(db, pExpr->pRight); - pExpr->pRight = 0; - pExpr->op = (isTrigger ? TK_TRIGGER : TK_COLUMN); -lookupname_end: - if( cnt==1 ){ - assert( pNC!=0 ); - if( !ExprHasProperty(pExpr, EP_Alias) ){ - sqlite3AuthRead(pParse, pExpr, pSchema, pNC->pSrcList); - } - /* Increment the nRef value on all name contexts from TopNC up to - ** the point where the name matched. */ - for(;;){ - assert( pTopNC!=0 ); - pTopNC->nRef++; - if( pTopNC==pNC ) break; - pTopNC = pTopNC->pNext; - } - return WRC_Prune; - } else { - return WRC_Abort; - } -} - -/* -** Allocate and return a pointer to an expression to load the column iCol -** from datasource iSrc in SrcList pSrc. -*/ -Expr *sqlite3CreateColumnExpr(sqlite3 *db, SrcList *pSrc, int iSrc, int iCol){ - Expr *p = sqlite3ExprAlloc(db, TK_COLUMN, 0, 0); - if( p ){ - struct SrcList_item *pItem = &pSrc->a[iSrc]; - p->pTab = pItem->pTab; - p->iTable = pItem->iCursor; - if( p->pTab->iPKey==iCol ){ - p->iColumn = -1; - }else{ - p->iColumn = (ynVar)iCol; - testcase( iCol==BMS ); - testcase( iCol==BMS-1 ); - pItem->colUsed |= ((Bitmask)1)<<(iCol>=BMS ? BMS-1 : iCol); - } - ExprSetProperty(p, EP_Resolved); - } - return p; -} - -/* -** Report an error that an expression is not valid for some set of -** pNC->ncFlags values determined by validMask. -*/ -static void notValid( - Parse *pParse, /* Leave error message here */ - NameContext *pNC, /* The name context */ - const char *zMsg, /* Type of error */ - int validMask /* Set of contexts for which prohibited */ -){ - assert( (validMask&~(NC_IsCheck|NC_PartIdx|NC_IdxExpr))==0 ); - if( (pNC->ncFlags & validMask)!=0 ){ - const char *zIn = "partial index WHERE clauses"; - if( pNC->ncFlags & NC_IdxExpr ) zIn = "index expressions"; -#ifndef SQLITE_OMIT_CHECK - else if( pNC->ncFlags & NC_IsCheck ) zIn = "CHECK constraints"; -#endif - sqlite3ErrorMsg(pParse, "%s prohibited in %s", zMsg, zIn); - } -} - -/* -** Expression p should encode a floating point value between 1.0 and 0.0. -** Return 1024 times this value. Or return -1 if p is not a floating point -** value between 1.0 and 0.0. -*/ -static int exprProbability(Expr *p){ - double r = -1.0; - if( p->op!=TK_FLOAT ) return -1; - sqlite3AtoF(p->u.zToken, &r, sqlite3Strlen30(p->u.zToken), SQLITE_UTF8); - assert( r>=0.0 ); - if( r>1.0 ) return -1; - return (int)(r*134217728.0); -} - -/* -** This routine is callback for sqlite3WalkExpr(). -** -** Resolve symbolic names into TK_COLUMN operators for the current -** node in the expression tree. Return 0 to continue the search down -** the tree or 2 to abort the tree walk. -** -** This routine also does error checking and name resolution for -** function names. The operator for aggregate functions is changed -** to TK_AGG_FUNCTION. -*/ -static int resolveExprStep(Walker *pWalker, Expr *pExpr){ - NameContext *pNC; - Parse *pParse; - - pNC = pWalker->u.pNC; - assert( pNC!=0 ); - pParse = pNC->pParse; - assert( pParse==pWalker->pParse ); - - if( ExprHasProperty(pExpr, EP_Resolved) ) return WRC_Prune; - ExprSetProperty(pExpr, EP_Resolved); -#ifndef NDEBUG - if( pNC->pSrcList && pNC->pSrcList->nAlloc>0 ){ - SrcList *pSrcList = pNC->pSrcList; - int i; - for(i=0; i<pNC->pSrcList->nSrc; i++){ - assert( pSrcList->a[i].iCursor>=0 && pSrcList->a[i].iCursor<pParse->nTab); - } - } -#endif - switch( pExpr->op ){ - -#if defined(SQLITE_ENABLE_UPDATE_DELETE_LIMIT) && !defined(SQLITE_OMIT_SUBQUERY) - /* The special operator TK_ROW means use the rowid for the first - ** column in the FROM clause. This is used by the LIMIT and ORDER BY - ** clause processing on UPDATE and DELETE statements. - */ - case TK_ROW: { - SrcList *pSrcList = pNC->pSrcList; - struct SrcList_item *pItem; - assert( pSrcList && pSrcList->nSrc==1 ); - pItem = pSrcList->a; - pExpr->op = TK_COLUMN; - pExpr->pTab = pItem->pTab; - pExpr->iTable = pItem->iCursor; - pExpr->iColumn = -1; - pExpr->affinity = SQLITE_AFF_INTEGER; - break; - } -#endif /* defined(SQLITE_ENABLE_UPDATE_DELETE_LIMIT) - && !defined(SQLITE_OMIT_SUBQUERY) */ - - /* A lone identifier is the name of a column. - */ - case TK_ID: { - return lookupName(pParse, 0, 0, pExpr->u.zToken, pNC, pExpr); - } - - /* A table name and column name: ID.ID - ** Or a database, table and column: ID.ID.ID - */ - case TK_DOT: { - const char *zColumn; - const char *zTable; - const char *zDb; - Expr *pRight; - - /* if( pSrcList==0 ) break; */ - notValid(pParse, pNC, "the \".\" operator", NC_IdxExpr); - /*notValid(pParse, pNC, "the \".\" operator", NC_PartIdx|NC_IsCheck, 1);*/ - pRight = pExpr->pRight; - if( pRight->op==TK_ID ){ - zDb = 0; - zTable = pExpr->pLeft->u.zToken; - zColumn = pRight->u.zToken; - }else{ - assert( pRight->op==TK_DOT ); - zDb = pExpr->pLeft->u.zToken; - zTable = pRight->pLeft->u.zToken; - zColumn = pRight->pRight->u.zToken; - } - return lookupName(pParse, zDb, zTable, zColumn, pNC, pExpr); - } - - /* Resolve function names - */ - case TK_FUNCTION: { - ExprList *pList = pExpr->x.pList; /* The argument list */ - int n = pList ? pList->nExpr : 0; /* Number of arguments */ - int no_such_func = 0; /* True if no such function exists */ - int wrong_num_args = 0; /* True if wrong number of arguments */ - int is_agg = 0; /* True if is an aggregate function */ - int auth; /* Authorization to use the function */ - int nId; /* Number of characters in function name */ - const char *zId; /* The function name. */ - FuncDef *pDef; /* Information about the function */ - u8 enc = ENC(pParse->db); /* The database encoding */ - - assert( !ExprHasProperty(pExpr, EP_xIsSelect) ); - notValid(pParse, pNC, "functions", NC_PartIdx); - zId = pExpr->u.zToken; - nId = sqlite3Strlen30(zId); - pDef = sqlite3FindFunction(pParse->db, zId, nId, n, enc, 0); - if( pDef==0 ){ - pDef = sqlite3FindFunction(pParse->db, zId, nId, -2, enc, 0); - if( pDef==0 ){ - no_such_func = 1; - }else{ - wrong_num_args = 1; - } - }else{ - is_agg = pDef->xFunc==0; - if( pDef->funcFlags & SQLITE_FUNC_UNLIKELY ){ - ExprSetProperty(pExpr, EP_Unlikely|EP_Skip); - if( n==2 ){ - pExpr->iTable = exprProbability(pList->a[1].pExpr); - if( pExpr->iTable<0 ){ - sqlite3ErrorMsg(pParse, - "second argument to likelihood() must be a " - "constant between 0.0 and 1.0"); - pNC->nErr++; - } - }else{ - /* EVIDENCE-OF: R-61304-29449 The unlikely(X) function is - ** equivalent to likelihood(X, 0.0625). - ** EVIDENCE-OF: R-01283-11636 The unlikely(X) function is - ** short-hand for likelihood(X,0.0625). - ** EVIDENCE-OF: R-36850-34127 The likely(X) function is short-hand - ** for likelihood(X,0.9375). - ** EVIDENCE-OF: R-53436-40973 The likely(X) function is equivalent - ** to likelihood(X,0.9375). */ - /* TUNING: unlikely() probability is 0.0625. likely() is 0.9375 */ - pExpr->iTable = pDef->zName[0]=='u' ? 8388608 : 125829120; - } - } -#ifndef SQLITE_OMIT_AUTHORIZATION - auth = sqlite3AuthCheck(pParse, SQLITE_FUNCTION, 0, pDef->zName, 0); - if( auth!=SQLITE_OK ){ - if( auth==SQLITE_DENY ){ - sqlite3ErrorMsg(pParse, "not authorized to use function: %s", - pDef->zName); - pNC->nErr++; - } - pExpr->op = TK_NULL; - return WRC_Prune; - } -#endif - if( pDef->funcFlags & (SQLITE_FUNC_CONSTANT|SQLITE_FUNC_SLOCHNG) ){ - /* For the purposes of the EP_ConstFunc flag, date and time - ** functions and other functions that change slowly are considered - ** constant because they are constant for the duration of one query */ - ExprSetProperty(pExpr,EP_ConstFunc); - } - if( (pDef->funcFlags & SQLITE_FUNC_CONSTANT)==0 ){ - /* Date/time functions that use 'now', and other functions like - ** sqlite_version() that might change over time cannot be used - ** in an index. */ - notValid(pParse, pNC, "non-deterministic functions", NC_IdxExpr); - } - } - if( is_agg && (pNC->ncFlags & NC_AllowAgg)==0 ){ - sqlite3ErrorMsg(pParse, "misuse of aggregate function %.*s()", nId,zId); - pNC->nErr++; - is_agg = 0; - }else if( no_such_func && pParse->db->init.busy==0 ){ - sqlite3ErrorMsg(pParse, "no such function: %.*s", nId, zId); - pNC->nErr++; - }else if( wrong_num_args ){ - sqlite3ErrorMsg(pParse,"wrong number of arguments to function %.*s()", - nId, zId); - pNC->nErr++; - } - if( is_agg ) pNC->ncFlags &= ~NC_AllowAgg; - sqlite3WalkExprList(pWalker, pList); - if( is_agg ){ - NameContext *pNC2 = pNC; - pExpr->op = TK_AGG_FUNCTION; - pExpr->op2 = 0; - while( pNC2 && !sqlite3FunctionUsesThisSrc(pExpr, pNC2->pSrcList) ){ - pExpr->op2++; - pNC2 = pNC2->pNext; - } - assert( pDef!=0 ); - if( pNC2 ){ - assert( SQLITE_FUNC_MINMAX==NC_MinMaxAgg ); - testcase( (pDef->funcFlags & SQLITE_FUNC_MINMAX)!=0 ); - pNC2->ncFlags |= NC_HasAgg | (pDef->funcFlags & SQLITE_FUNC_MINMAX); - - } - pNC->ncFlags |= NC_AllowAgg; - } - /* FIX ME: Compute pExpr->affinity based on the expected return - ** type of the function - */ - return WRC_Prune; - } -#ifndef SQLITE_OMIT_SUBQUERY - case TK_SELECT: - case TK_EXISTS: testcase( pExpr->op==TK_EXISTS ); -#endif - case TK_IN: { - testcase( pExpr->op==TK_IN ); - if( ExprHasProperty(pExpr, EP_xIsSelect) ){ - int nRef = pNC->nRef; - notValid(pParse, pNC, "subqueries", NC_IsCheck|NC_PartIdx|NC_IdxExpr); - sqlite3WalkSelect(pWalker, pExpr->x.pSelect); - assert( pNC->nRef>=nRef ); - if( nRef!=pNC->nRef ){ - ExprSetProperty(pExpr, EP_VarSelect); - } - } - break; - } - case TK_VARIABLE: { - notValid(pParse, pNC, "parameters", NC_IsCheck|NC_PartIdx|NC_IdxExpr); - break; - } - } - return (pParse->nErr || pParse->db->mallocFailed) ? WRC_Abort : WRC_Continue; -} - -/* -** pEList is a list of expressions which are really the result set of the -** a SELECT statement. pE is a term in an ORDER BY or GROUP BY clause. -** This routine checks to see if pE is a simple identifier which corresponds -** to the AS-name of one of the terms of the expression list. If it is, -** this routine return an integer between 1 and N where N is the number of -** elements in pEList, corresponding to the matching entry. If there is -** no match, or if pE is not a simple identifier, then this routine -** return 0. -** -** pEList has been resolved. pE has not. -*/ -static int resolveAsName( - Parse *pParse, /* Parsing context for error messages */ - ExprList *pEList, /* List of expressions to scan */ - Expr *pE /* Expression we are trying to match */ -){ - int i; /* Loop counter */ - - UNUSED_PARAMETER(pParse); - - if( pE->op==TK_ID ){ - char *zCol = pE->u.zToken; - for(i=0; i<pEList->nExpr; i++){ - char *zAs = pEList->a[i].zName; - if( zAs!=0 && sqlite3StrICmp(zAs, zCol)==0 ){ - return i+1; - } - } - } - return 0; -} - -/* -** pE is a pointer to an expression which is a single term in the -** ORDER BY of a compound SELECT. The expression has not been -** name resolved. -** -** At the point this routine is called, we already know that the -** ORDER BY term is not an integer index into the result set. That -** case is handled by the calling routine. -** -** Attempt to match pE against result set columns in the left-most -** SELECT statement. Return the index i of the matching column, -** as an indication to the caller that it should sort by the i-th column. -** The left-most column is 1. In other words, the value returned is the -** same integer value that would be used in the SQL statement to indicate -** the column. -** -** If there is no match, return 0. Return -1 if an error occurs. -*/ -static int resolveOrderByTermToExprList( - Parse *pParse, /* Parsing context for error messages */ - Select *pSelect, /* The SELECT statement with the ORDER BY clause */ - Expr *pE /* The specific ORDER BY term */ -){ - int i; /* Loop counter */ - ExprList *pEList; /* The columns of the result set */ - NameContext nc; /* Name context for resolving pE */ - sqlite3 *db; /* Database connection */ - int rc; /* Return code from subprocedures */ - u8 savedSuppErr; /* Saved value of db->suppressErr */ - - assert( sqlite3ExprIsInteger(pE, &i)==0 ); - pEList = pSelect->pEList; - - /* Resolve all names in the ORDER BY term expression - */ - memset(&nc, 0, sizeof(nc)); - nc.pParse = pParse; - nc.pSrcList = pSelect->pSrc; - nc.pEList = pEList; - nc.ncFlags = NC_AllowAgg; - nc.nErr = 0; - db = pParse->db; - savedSuppErr = db->suppressErr; - db->suppressErr = 1; - rc = sqlite3ResolveExprNames(&nc, pE); - db->suppressErr = savedSuppErr; - if( rc ) return 0; - - /* Try to match the ORDER BY expression against an expression - ** in the result set. Return an 1-based index of the matching - ** result-set entry. - */ - for(i=0; i<pEList->nExpr; i++){ - if( sqlite3ExprCompare(pEList->a[i].pExpr, pE, -1)<2 ){ - return i+1; - } - } - - /* If no match, return 0. */ - return 0; -} - -/* -** Generate an ORDER BY or GROUP BY term out-of-range error. -*/ -static void resolveOutOfRangeError( - Parse *pParse, /* The error context into which to write the error */ - const char *zType, /* "ORDER" or "GROUP" */ - int i, /* The index (1-based) of the term out of range */ - int mx /* Largest permissible value of i */ -){ - sqlite3ErrorMsg(pParse, - "%r %s BY term out of range - should be " - "between 1 and %d", i, zType, mx); -} - -/* -** Analyze the ORDER BY clause in a compound SELECT statement. Modify -** each term of the ORDER BY clause is a constant integer between 1 -** and N where N is the number of columns in the compound SELECT. -** -** ORDER BY terms that are already an integer between 1 and N are -** unmodified. ORDER BY terms that are integers outside the range of -** 1 through N generate an error. ORDER BY terms that are expressions -** are matched against result set expressions of compound SELECT -** beginning with the left-most SELECT and working toward the right. -** At the first match, the ORDER BY expression is transformed into -** the integer column number. -** -** Return the number of errors seen. -*/ -static int resolveCompoundOrderBy( - Parse *pParse, /* Parsing context. Leave error messages here */ - Select *pSelect /* The SELECT statement containing the ORDER BY */ -){ - int i; - ExprList *pOrderBy; - ExprList *pEList; - sqlite3 *db; - int moreToDo = 1; - - pOrderBy = pSelect->pOrderBy; - if( pOrderBy==0 ) return 0; - db = pParse->db; -#if SQLITE_MAX_COLUMN - if( pOrderBy->nExpr>db->aLimit[SQLITE_LIMIT_COLUMN] ){ - sqlite3ErrorMsg(pParse, "too many terms in ORDER BY clause"); - return 1; - } -#endif - for(i=0; i<pOrderBy->nExpr; i++){ - pOrderBy->a[i].done = 0; - } - pSelect->pNext = 0; - while( pSelect->pPrior ){ - pSelect->pPrior->pNext = pSelect; - pSelect = pSelect->pPrior; - } - while( pSelect && moreToDo ){ - struct ExprList_item *pItem; - moreToDo = 0; - pEList = pSelect->pEList; - assert( pEList!=0 ); - for(i=0, pItem=pOrderBy->a; i<pOrderBy->nExpr; i++, pItem++){ - int iCol = -1; - Expr *pE, *pDup; - if( pItem->done ) continue; - pE = sqlite3ExprSkipCollate(pItem->pExpr); - if( sqlite3ExprIsInteger(pE, &iCol) ){ - if( iCol<=0 || iCol>pEList->nExpr ){ - resolveOutOfRangeError(pParse, "ORDER", i+1, pEList->nExpr); - return 1; - } - }else{ - iCol = resolveAsName(pParse, pEList, pE); - if( iCol==0 ){ - pDup = sqlite3ExprDup(db, pE, 0); - if( !db->mallocFailed ){ - assert(pDup); - iCol = resolveOrderByTermToExprList(pParse, pSelect, pDup); - } - sqlite3ExprDelete(db, pDup); - } - } - if( iCol>0 ){ - /* Convert the ORDER BY term into an integer column number iCol, - ** taking care to preserve the COLLATE clause if it exists */ - Expr *pNew = sqlite3Expr(db, TK_INTEGER, 0); - if( pNew==0 ) return 1; - pNew->flags |= EP_IntValue; - pNew->u.iValue = iCol; - if( pItem->pExpr==pE ){ - pItem->pExpr = pNew; - }else{ - Expr *pParent = pItem->pExpr; - assert( pParent->op==TK_COLLATE ); - while( pParent->pLeft->op==TK_COLLATE ) pParent = pParent->pLeft; - assert( pParent->pLeft==pE ); - pParent->pLeft = pNew; - } - sqlite3ExprDelete(db, pE); - pItem->u.x.iOrderByCol = (u16)iCol; - pItem->done = 1; - }else{ - moreToDo = 1; - } - } - pSelect = pSelect->pNext; - } - for(i=0; i<pOrderBy->nExpr; i++){ - if( pOrderBy->a[i].done==0 ){ - sqlite3ErrorMsg(pParse, "%r ORDER BY term does not match any " - "column in the result set", i+1); - return 1; - } - } - return 0; -} - -/* -** Check every term in the ORDER BY or GROUP BY clause pOrderBy of -** the SELECT statement pSelect. If any term is reference to a -** result set expression (as determined by the ExprList.a.u.x.iOrderByCol -** field) then convert that term into a copy of the corresponding result set -** column. -** -** If any errors are detected, add an error message to pParse and -** return non-zero. Return zero if no errors are seen. -*/ -int sqlite3ResolveOrderGroupBy( - Parse *pParse, /* Parsing context. Leave error messages here */ - Select *pSelect, /* The SELECT statement containing the clause */ - ExprList *pOrderBy, /* The ORDER BY or GROUP BY clause to be processed */ - const char *zType /* "ORDER" or "GROUP" */ -){ - int i; - sqlite3 *db = pParse->db; - ExprList *pEList; - struct ExprList_item *pItem; - - if( pOrderBy==0 || pParse->db->mallocFailed ) return 0; -#if SQLITE_MAX_COLUMN - if( pOrderBy->nExpr>db->aLimit[SQLITE_LIMIT_COLUMN] ){ - sqlite3ErrorMsg(pParse, "too many terms in %s BY clause", zType); - return 1; - } -#endif - pEList = pSelect->pEList; - assert( pEList!=0 ); /* sqlite3SelectNew() guarantees this */ - for(i=0, pItem=pOrderBy->a; i<pOrderBy->nExpr; i++, pItem++){ - if( pItem->u.x.iOrderByCol ){ - if( pItem->u.x.iOrderByCol>pEList->nExpr ){ - resolveOutOfRangeError(pParse, zType, i+1, pEList->nExpr); - return 1; - } - resolveAlias(pParse, pEList, pItem->u.x.iOrderByCol-1, pItem->pExpr, - zType,0); - } - } - return 0; -} - -/* -** pOrderBy is an ORDER BY or GROUP BY clause in SELECT statement pSelect. -** The Name context of the SELECT statement is pNC. zType is either -** "ORDER" or "GROUP" depending on which type of clause pOrderBy is. -** -** This routine resolves each term of the clause into an expression. -** If the order-by term is an integer I between 1 and N (where N is the -** number of columns in the result set of the SELECT) then the expression -** in the resolution is a copy of the I-th result-set expression. If -** the order-by term is an identifier that corresponds to the AS-name of -** a result-set expression, then the term resolves to a copy of the -** result-set expression. Otherwise, the expression is resolved in -** the usual way - using sqlite3ResolveExprNames(). -** -** This routine returns the number of errors. If errors occur, then -** an appropriate error message might be left in pParse. (OOM errors -** excepted.) -*/ -static int resolveOrderGroupBy( - NameContext *pNC, /* The name context of the SELECT statement */ - Select *pSelect, /* The SELECT statement holding pOrderBy */ - ExprList *pOrderBy, /* An ORDER BY or GROUP BY clause to resolve */ - const char *zType /* Either "ORDER" or "GROUP", as appropriate */ -){ - int i, j; /* Loop counters */ - int iCol; /* Column number */ - struct ExprList_item *pItem; /* A term of the ORDER BY clause */ - Parse *pParse; /* Parsing context */ - int nResult; /* Number of terms in the result set */ - - if( pOrderBy==0 ) return 0; - nResult = pSelect->pEList->nExpr; - pParse = pNC->pParse; - for(i=0, pItem=pOrderBy->a; i<pOrderBy->nExpr; i++, pItem++){ - Expr *pE = pItem->pExpr; - Expr *pE2 = sqlite3ExprSkipCollate(pE); - if( zType[0]!='G' ){ - iCol = resolveAsName(pParse, pSelect->pEList, pE2); - if( iCol>0 ){ - /* If an AS-name match is found, mark this ORDER BY column as being - ** a copy of the iCol-th result-set column. The subsequent call to - ** sqlite3ResolveOrderGroupBy() will convert the expression to a - ** copy of the iCol-th result-set expression. */ - pItem->u.x.iOrderByCol = (u16)iCol; - continue; - } - } - if( sqlite3ExprIsInteger(pE2, &iCol) ){ - /* The ORDER BY term is an integer constant. Again, set the column - ** number so that sqlite3ResolveOrderGroupBy() will convert the - ** order-by term to a copy of the result-set expression */ - if( iCol<1 || iCol>0xffff ){ - resolveOutOfRangeError(pParse, zType, i+1, nResult); - return 1; - } - pItem->u.x.iOrderByCol = (u16)iCol; - continue; - } - - /* Otherwise, treat the ORDER BY term as an ordinary expression */ - pItem->u.x.iOrderByCol = 0; - if( sqlite3ResolveExprNames(pNC, pE) ){ - return 1; - } - for(j=0; j<pSelect->pEList->nExpr; j++){ - if( sqlite3ExprCompare(pE, pSelect->pEList->a[j].pExpr, -1)==0 ){ - pItem->u.x.iOrderByCol = j+1; - } - } - } - return sqlite3ResolveOrderGroupBy(pParse, pSelect, pOrderBy, zType); -} - -/* -** Resolve names in the SELECT statement p and all of its descendants. -*/ -static int resolveSelectStep(Walker *pWalker, Select *p){ - NameContext *pOuterNC; /* Context that contains this SELECT */ - NameContext sNC; /* Name context of this SELECT */ - int isCompound; /* True if p is a compound select */ - int nCompound; /* Number of compound terms processed so far */ - Parse *pParse; /* Parsing context */ - int i; /* Loop counter */ - ExprList *pGroupBy; /* The GROUP BY clause */ - Select *pLeftmost; /* Left-most of SELECT of a compound */ - sqlite3 *db; /* Database connection */ - - - assert( p!=0 ); - if( p->selFlags & SF_Resolved ){ - return WRC_Prune; - } - pOuterNC = pWalker->u.pNC; - pParse = pWalker->pParse; - db = pParse->db; - - /* Normally sqlite3SelectExpand() will be called first and will have - ** already expanded this SELECT. However, if this is a subquery within - ** an expression, sqlite3ResolveExprNames() will be called without a - ** prior call to sqlite3SelectExpand(). When that happens, let - ** sqlite3SelectPrep() do all of the processing for this SELECT. - ** sqlite3SelectPrep() will invoke both sqlite3SelectExpand() and - ** this routine in the correct order. - */ - if( (p->selFlags & SF_Expanded)==0 ){ - sqlite3SelectPrep(pParse, p, pOuterNC); - return (pParse->nErr || db->mallocFailed) ? WRC_Abort : WRC_Prune; - } - - isCompound = p->pPrior!=0; - nCompound = 0; - pLeftmost = p; - while( p ){ - assert( (p->selFlags & SF_Expanded)!=0 ); - assert( (p->selFlags & SF_Resolved)==0 ); - p->selFlags |= SF_Resolved; - - /* Resolve the expressions in the LIMIT and OFFSET clauses. These - ** are not allowed to refer to any names, so pass an empty NameContext. - */ - memset(&sNC, 0, sizeof(sNC)); - sNC.pParse = pParse; - if( sqlite3ResolveExprNames(&sNC, p->pLimit) || - sqlite3ResolveExprNames(&sNC, p->pOffset) ){ - return WRC_Abort; - } - - /* If the SF_Converted flags is set, then this Select object was - ** was created by the convertCompoundSelectToSubquery() function. - ** In this case the ORDER BY clause (p->pOrderBy) should be resolved - ** as if it were part of the sub-query, not the parent. This block - ** moves the pOrderBy down to the sub-query. It will be moved back - ** after the names have been resolved. */ - if( p->selFlags & SF_Converted ){ - Select *pSub = p->pSrc->a[0].pSelect; - assert( p->pSrc->nSrc==1 && p->pOrderBy ); - assert( pSub->pPrior && pSub->pOrderBy==0 ); - pSub->pOrderBy = p->pOrderBy; - p->pOrderBy = 0; - } - - /* Recursively resolve names in all subqueries - */ - for(i=0; i<p->pSrc->nSrc; i++){ - struct SrcList_item *pItem = &p->pSrc->a[i]; - if( pItem->pSelect ){ - NameContext *pNC; /* Used to iterate name contexts */ - int nRef = 0; /* Refcount for pOuterNC and outer contexts */ - const char *zSavedContext = pParse->zAuthContext; - - /* Count the total number of references to pOuterNC and all of its - ** parent contexts. After resolving references to expressions in - ** pItem->pSelect, check if this value has changed. If so, then - ** SELECT statement pItem->pSelect must be correlated. Set the - ** pItem->fg.isCorrelated flag if this is the case. */ - for(pNC=pOuterNC; pNC; pNC=pNC->pNext) nRef += pNC->nRef; - - if( pItem->zName ) pParse->zAuthContext = pItem->zName; - sqlite3ResolveSelectNames(pParse, pItem->pSelect, pOuterNC); - pParse->zAuthContext = zSavedContext; - if( pParse->nErr || db->mallocFailed ) return WRC_Abort; - - for(pNC=pOuterNC; pNC; pNC=pNC->pNext) nRef -= pNC->nRef; - assert( pItem->fg.isCorrelated==0 && nRef<=0 ); - pItem->fg.isCorrelated = (nRef!=0); - } - } - - /* Set up the local name-context to pass to sqlite3ResolveExprNames() to - ** resolve the result-set expression list. - */ - sNC.ncFlags = NC_AllowAgg; - sNC.pSrcList = p->pSrc; - sNC.pNext = pOuterNC; - - /* Resolve names in the result set. */ - if( sqlite3ResolveExprListNames(&sNC, p->pEList) ) return WRC_Abort; - - /* If there are no aggregate functions in the result-set, and no GROUP BY - ** expression, do not allow aggregates in any of the other expressions. - */ - assert( (p->selFlags & SF_Aggregate)==0 ); - pGroupBy = p->pGroupBy; - if( pGroupBy || (sNC.ncFlags & NC_HasAgg)!=0 ){ - assert( NC_MinMaxAgg==SF_MinMaxAgg ); - p->selFlags |= SF_Aggregate | (sNC.ncFlags&NC_MinMaxAgg); - }else{ - sNC.ncFlags &= ~NC_AllowAgg; - } - - /* If a HAVING clause is present, then there must be a GROUP BY clause. - */ - if( p->pHaving && !pGroupBy ){ - sqlite3ErrorMsg(pParse, "a GROUP BY clause is required before HAVING"); - return WRC_Abort; - } - - /* Add the output column list to the name-context before parsing the - ** other expressions in the SELECT statement. This is so that - ** expressions in the WHERE clause (etc.) can refer to expressions by - ** aliases in the result set. - ** - ** Minor point: If this is the case, then the expression will be - ** re-evaluated for each reference to it. - */ - sNC.pEList = p->pEList; - if( sqlite3ResolveExprNames(&sNC, p->pHaving) ) return WRC_Abort; - if( sqlite3ResolveExprNames(&sNC, p->pWhere) ) return WRC_Abort; - - /* Resolve names in table-valued-function arguments */ - for(i=0; i<p->pSrc->nSrc; i++){ - struct SrcList_item *pItem = &p->pSrc->a[i]; - if( pItem->fg.isTabFunc - && sqlite3ResolveExprListNames(&sNC, pItem->u1.pFuncArg) - ){ - return WRC_Abort; - } - } - - /* The ORDER BY and GROUP BY clauses may not refer to terms in - ** outer queries - */ - sNC.pNext = 0; - sNC.ncFlags |= NC_AllowAgg; - - /* If this is a converted compound query, move the ORDER BY clause from - ** the sub-query back to the parent query. At this point each term - ** within the ORDER BY clause has been transformed to an integer value. - ** These integers will be replaced by copies of the corresponding result - ** set expressions by the call to resolveOrderGroupBy() below. */ - if( p->selFlags & SF_Converted ){ - Select *pSub = p->pSrc->a[0].pSelect; - p->pOrderBy = pSub->pOrderBy; - pSub->pOrderBy = 0; - } - - /* Process the ORDER BY clause for singleton SELECT statements. - ** The ORDER BY clause for compounds SELECT statements is handled - ** below, after all of the result-sets for all of the elements of - ** the compound have been resolved. - ** - ** If there is an ORDER BY clause on a term of a compound-select other - ** than the right-most term, then that is a syntax error. But the error - ** is not detected until much later, and so we need to go ahead and - ** resolve those symbols on the incorrect ORDER BY for consistency. - */ - if( isCompound<=nCompound /* Defer right-most ORDER BY of a compound */ - && resolveOrderGroupBy(&sNC, p, p->pOrderBy, "ORDER") - ){ - return WRC_Abort; - } - if( db->mallocFailed ){ - return WRC_Abort; - } - - /* Resolve the GROUP BY clause. At the same time, make sure - ** the GROUP BY clause does not contain aggregate functions. - */ - if( pGroupBy ){ - struct ExprList_item *pItem; - - if( resolveOrderGroupBy(&sNC, p, pGroupBy, "GROUP") || db->mallocFailed ){ - return WRC_Abort; - } - for(i=0, pItem=pGroupBy->a; i<pGroupBy->nExpr; i++, pItem++){ - if( ExprHasProperty(pItem->pExpr, EP_Agg) ){ - sqlite3ErrorMsg(pParse, "aggregate functions are not allowed in " - "the GROUP BY clause"); - return WRC_Abort; - } - } - } - - /* If this is part of a compound SELECT, check that it has the right - ** number of expressions in the select list. */ - if( p->pNext && p->pEList->nExpr!=p->pNext->pEList->nExpr ){ - sqlite3SelectWrongNumTermsError(pParse, p->pNext); - return WRC_Abort; - } - - /* Advance to the next term of the compound - */ - p = p->pPrior; - nCompound++; - } - - /* Resolve the ORDER BY on a compound SELECT after all terms of - ** the compound have been resolved. - */ - if( isCompound && resolveCompoundOrderBy(pParse, pLeftmost) ){ - return WRC_Abort; - } - - return WRC_Prune; -} - -/* -** This routine walks an expression tree and resolves references to -** table columns and result-set columns. At the same time, do error -** checking on function usage and set a flag if any aggregate functions -** are seen. -** -** To resolve table columns references we look for nodes (or subtrees) of the -** form X.Y.Z or Y.Z or just Z where -** -** X: The name of a database. Ex: "main" or "temp" or -** the symbolic name assigned to an ATTACH-ed database. -** -** Y: The name of a table in a FROM clause. Or in a trigger -** one of the special names "old" or "new". -** -** Z: The name of a column in table Y. -** -** The node at the root of the subtree is modified as follows: -** -** Expr.op Changed to TK_COLUMN -** Expr.pTab Points to the Table object for X.Y -** Expr.iColumn The column index in X.Y. -1 for the rowid. -** Expr.iTable The VDBE cursor number for X.Y -** -** -** To resolve result-set references, look for expression nodes of the -** form Z (with no X and Y prefix) where the Z matches the right-hand -** size of an AS clause in the result-set of a SELECT. The Z expression -** is replaced by a copy of the left-hand side of the result-set expression. -** Table-name and function resolution occurs on the substituted expression -** tree. For example, in: -** -** SELECT a+b AS x, c+d AS y FROM t1 ORDER BY x; -** -** The "x" term of the order by is replaced by "a+b" to render: -** -** SELECT a+b AS x, c+d AS y FROM t1 ORDER BY a+b; -** -** Function calls are checked to make sure that the function is -** defined and that the correct number of arguments are specified. -** If the function is an aggregate function, then the NC_HasAgg flag is -** set and the opcode is changed from TK_FUNCTION to TK_AGG_FUNCTION. -** If an expression contains aggregate functions then the EP_Agg -** property on the expression is set. -** -** An error message is left in pParse if anything is amiss. The number -** if errors is returned. -*/ -int sqlite3ResolveExprNames( - NameContext *pNC, /* Namespace to resolve expressions in. */ - Expr *pExpr /* The expression to be analyzed. */ -){ - u16 savedHasAgg; - Walker w; - - if( pExpr==0 ) return 0; -#if SQLITE_MAX_EXPR_DEPTH>0 - { - Parse *pParse = pNC->pParse; - if( sqlite3ExprCheckHeight(pParse, pExpr->nHeight+pNC->pParse->nHeight) ){ - return 1; - } - pParse->nHeight += pExpr->nHeight; - } -#endif - savedHasAgg = pNC->ncFlags & (NC_HasAgg|NC_MinMaxAgg); - pNC->ncFlags &= ~(NC_HasAgg|NC_MinMaxAgg); - memset(&w, 0, sizeof(w)); - w.xExprCallback = resolveExprStep; - w.xSelectCallback = resolveSelectStep; - w.pParse = pNC->pParse; - w.u.pNC = pNC; - sqlite3WalkExpr(&w, pExpr); -#if SQLITE_MAX_EXPR_DEPTH>0 - pNC->pParse->nHeight -= pExpr->nHeight; -#endif - if( pNC->nErr>0 || w.pParse->nErr>0 ){ - ExprSetProperty(pExpr, EP_Error); - } - if( pNC->ncFlags & NC_HasAgg ){ - ExprSetProperty(pExpr, EP_Agg); - } - pNC->ncFlags |= savedHasAgg; - return ExprHasProperty(pExpr, EP_Error); -} - -/* -** Resolve all names for all expression in an expression list. This is -** just like sqlite3ResolveExprNames() except that it works for an expression -** list rather than a single expression. -*/ -int sqlite3ResolveExprListNames( - NameContext *pNC, /* Namespace to resolve expressions in. */ - ExprList *pList /* The expression list to be analyzed. */ -){ - int i; - assert( pList!=0 ); - for(i=0; i<pList->nExpr; i++){ - if( sqlite3ResolveExprNames(pNC, pList->a[i].pExpr) ) return WRC_Abort; - } - return WRC_Continue; -} - -/* -** Resolve all names in all expressions of a SELECT and in all -** decendents of the SELECT, including compounds off of p->pPrior, -** subqueries in expressions, and subqueries used as FROM clause -** terms. -** -** See sqlite3ResolveExprNames() for a description of the kinds of -** transformations that occur. -** -** All SELECT statements should have been expanded using -** sqlite3SelectExpand() prior to invoking this routine. -*/ -void sqlite3ResolveSelectNames( - Parse *pParse, /* The parser context */ - Select *p, /* The SELECT statement being coded. */ - NameContext *pOuterNC /* Name context for parent SELECT statement */ -){ - Walker w; - - assert( p!=0 ); - memset(&w, 0, sizeof(w)); - w.xExprCallback = resolveExprStep; - w.xSelectCallback = resolveSelectStep; - w.pParse = pParse; - w.u.pNC = pOuterNC; - sqlite3WalkSelect(&w, p); -} - -/* -** Resolve names in expressions that can only reference a single table: -** -** * CHECK constraints -** * WHERE clauses on partial indices -** -** The Expr.iTable value for Expr.op==TK_COLUMN nodes of the expression -** is set to -1 and the Expr.iColumn value is set to the column number. -** -** Any errors cause an error message to be set in pParse. -*/ -void sqlite3ResolveSelfReference( - Parse *pParse, /* Parsing context */ - Table *pTab, /* The table being referenced */ - int type, /* NC_IsCheck or NC_PartIdx or NC_IdxExpr */ - Expr *pExpr, /* Expression to resolve. May be NULL. */ - ExprList *pList /* Expression list to resolve. May be NUL. */ -){ - SrcList sSrc; /* Fake SrcList for pParse->pNewTable */ - NameContext sNC; /* Name context for pParse->pNewTable */ - - assert( type==NC_IsCheck || type==NC_PartIdx || type==NC_IdxExpr ); - memset(&sNC, 0, sizeof(sNC)); - memset(&sSrc, 0, sizeof(sSrc)); - sSrc.nSrc = 1; - sSrc.a[0].zName = pTab->zName; - sSrc.a[0].pTab = pTab; - sSrc.a[0].iCursor = -1; - sNC.pParse = pParse; - sNC.pSrcList = &sSrc; - sNC.ncFlags = type; - if( sqlite3ResolveExprNames(&sNC, pExpr) ) return; - if( pList ) sqlite3ResolveExprListNames(&sNC, pList); -} |