| /* | 
 | ** 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" | 
 |  | 
 | /* | 
 | ** Magic table number to mean the EXCLUDED table in an UPSERT statement. | 
 | */ | 
 | #define EXCLUDED_TABLE_NUMBER  2 | 
 |  | 
 | /* | 
 | ** 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. | 
 | ** | 
 | ** See also the sqlite3WindowExtraAggFuncDepth() routine in window.c | 
 | */ | 
 | 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 ){ | 
 |     if( zType[0]!='G' ) incrAggFunctionDepth(pDup, nSubquery); | 
 |     if( pExpr->op==TK_COLLATE ){ | 
 |       pDup = sqlite3ExprAddCollateString(pParse, pDup, pExpr->u.zToken); | 
 |     } | 
 |  | 
 |     /* 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; | 
 |     } | 
 |     if( ExprHasProperty(pExpr, EP_WinFunc) ){ | 
 |       if( pExpr->y.pWin!=0 ){ | 
 |         pExpr->y.pWin->pOwner = pExpr; | 
 |       }else{ | 
 |         assert( db->mallocFailed ); | 
 |       } | 
 |     } | 
 |     sqlite3DbFree(db, pDup); | 
 |   } | 
 |   ExprSetProperty(pExpr, EP_Alias); | 
 | } | 
 |  | 
 |  | 
 | /* | 
 | ** 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 sqlite3MatchEName( | 
 |   const struct ExprList_item *pItem, | 
 |   const char *zCol, | 
 |   const char *zTab, | 
 |   const char *zDb | 
 | ){ | 
 |   int n; | 
 |   const char *zSpan; | 
 |   if( pItem->eEName!=ENAME_TAB ) return 0; | 
 |   zSpan = pItem->zEName; | 
 |   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; | 
 | } | 
 |  | 
 | /* | 
 | ** Return TRUE if the double-quoted string  mis-feature should be supported. | 
 | */ | 
 | static int areDoubleQuotedStringsEnabled(sqlite3 *db, NameContext *pTopNC){ | 
 |   if( db->init.busy ) return 1;  /* Always support for legacy schemas */ | 
 |   if( pTopNC->ncFlags & NC_IsDDL ){ | 
 |     /* Currently parsing a DDL statement */ | 
 |     if( sqlite3WritableSchema(db) && (db->flags & SQLITE_DqsDML)!=0 ){ | 
 |       return 1; | 
 |     } | 
 |     return (db->flags & SQLITE_DqsDDL)!=0; | 
 |   }else{ | 
 |     /* Currently parsing a DML statement */ | 
 |     return (db->flags & SQLITE_DqsDML)!=0; | 
 |   } | 
 | } | 
 |  | 
 | /* | 
 | ** The argument is guaranteed to be a non-NULL Expr node of type TK_COLUMN. | 
 | ** return the appropriate colUsed mask. | 
 | */ | 
 | Bitmask sqlite3ExprColUsed(Expr *pExpr){ | 
 |   int n; | 
 |   Table *pExTab; | 
 |  | 
 |   n = pExpr->iColumn; | 
 |   pExTab = pExpr->y.pTab; | 
 |   assert( pExTab!=0 ); | 
 |   if( (pExTab->tabFlags & TF_HasGenerated)!=0 | 
 |    && (pExTab->aCol[n].colFlags & COLFLAG_GENERATED)!=0  | 
 |   ){ | 
 |     testcase( pExTab->nCol==BMS-1 ); | 
 |     testcase( pExTab->nCol==BMS ); | 
 |     return pExTab->nCol>=BMS ? ALLBITS : MASKBIT(pExTab->nCol)-1; | 
 |   }else{ | 
 |     testcase( n==BMS-1 ); | 
 |     testcase( n==BMS ); | 
 |     if( n>=BMS ) n = BMS-1; | 
 |     return ((Bitmask)1)<<n; | 
 |   } | 
 | } | 
 |  | 
 | /* | 
 | ** 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->y.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 eNewExprOp = TK_COLUMN;       /* New value for pExpr->op on success */ | 
 |   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; | 
 |   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].zDbSName ); | 
 |         if( sqlite3StrICmp(db->aDb[i].zDbSName,zDb)==0 ){ | 
 |           pSchema = db->aDb[i].pSchema; | 
 |           break; | 
 |         } | 
 |       } | 
 |       if( i==db->nDb && sqlite3StrICmp("main", zDb)==0 ){ | 
 |         /* This branch is taken when the main database has been renamed | 
 |         ** using SQLITE_DBCONFIG_MAINDBNAME. */ | 
 |         pSchema = db->aDb[0].pSchema; | 
 |         zDb = db->aDb[0].zDbSName; | 
 |       } | 
 |     } | 
 |   } | 
 |  | 
 |   /* Start at the inner-most context and move outward until a match is found */ | 
 |   assert( pNC && cnt==0 ); | 
 |   do{ | 
 |     ExprList *pEList; | 
 |     SrcList *pSrcList = pNC->pSrcList; | 
 |  | 
 |     if( pSrcList ){ | 
 |       for(i=0, pItem=pSrcList->a; i<pSrcList->nSrc; i++, pItem++){ | 
 |         u8 hCol; | 
 |         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( sqlite3MatchEName(&pEList->a[j], 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( IN_RENAME_OBJECT && pItem->zAlias ){ | 
 |             sqlite3RenameTokenRemap(pParse, 0, (void*)&pExpr->y.pTab); | 
 |           } | 
 |         } | 
 |         if( 0==(cntTab++) ){ | 
 |           pMatch = pItem; | 
 |         } | 
 |         hCol = sqlite3StrIHash(zCol); | 
 |         for(j=0, pCol=pTab->aCol; j<pTab->nCol; j++, pCol++){ | 
 |           if( pCol->hName==hCol && 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->y.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->y.pTab->pSchema; | 
 |       } | 
 |     } /* if( pSrcList ) */ | 
 |  | 
 | #if !defined(SQLITE_OMIT_TRIGGER) || !defined(SQLITE_OMIT_UPSERT) | 
 |     /* If we have not already resolved the name, then maybe  | 
 |     ** it is a new.* or old.* trigger argument reference.  Or | 
 |     ** maybe it is an excluded.* from an upsert. | 
 |     */ | 
 |     if( zDb==0 && zTab!=0 && cntTab==0 ){ | 
 |       pTab = 0; | 
 | #ifndef SQLITE_OMIT_TRIGGER | 
 |       if( 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; | 
 |         } | 
 |       } | 
 | #endif /* SQLITE_OMIT_TRIGGER */ | 
 | #ifndef SQLITE_OMIT_UPSERT | 
 |       if( (pNC->ncFlags & NC_UUpsert)!=0 ){ | 
 |         Upsert *pUpsert = pNC->uNC.pUpsert; | 
 |         if( pUpsert && sqlite3StrICmp("excluded",zTab)==0 ){ | 
 |           pTab = pUpsert->pUpsertSrc->a[0].pTab; | 
 |           pExpr->iTable = EXCLUDED_TABLE_NUMBER; | 
 |         } | 
 |       } | 
 | #endif /* SQLITE_OMIT_UPSERT */ | 
 |  | 
 |       if( pTab ){  | 
 |         int iCol; | 
 |         u8 hCol = sqlite3StrIHash(zCol); | 
 |         pSchema = pTab->pSchema; | 
 |         cntTab++; | 
 |         for(iCol=0, pCol=pTab->aCol; iCol<pTab->nCol; iCol++, pCol++){ | 
 |           if( pCol->hName==hCol && sqlite3StrICmp(pCol->zName, zCol)==0 ){ | 
 |             if( iCol==pTab->iPKey ){ | 
 |               iCol = -1; | 
 |             } | 
 |             break; | 
 |           } | 
 |         } | 
 |         if( iCol>=pTab->nCol && sqlite3IsRowid(zCol) && VisibleRowid(pTab) ){ | 
 |           /* IMP: R-51414-32910 */ | 
 |           iCol = -1; | 
 |         } | 
 |         if( iCol<pTab->nCol ){ | 
 |           cnt++; | 
 | #ifndef SQLITE_OMIT_UPSERT | 
 |           if( pExpr->iTable==EXCLUDED_TABLE_NUMBER ){ | 
 |             testcase( iCol==(-1) ); | 
 |             if( IN_RENAME_OBJECT ){ | 
 |               pExpr->iColumn = iCol; | 
 |               pExpr->y.pTab = pTab; | 
 |               eNewExprOp = TK_COLUMN; | 
 |             }else{ | 
 |               pExpr->iTable = pNC->uNC.pUpsert->regData + | 
 |                  sqlite3TableColumnToStorage(pTab, iCol); | 
 |               eNewExprOp = TK_REGISTER; | 
 |               ExprSetProperty(pExpr, EP_Alias); | 
 |             } | 
 |           }else | 
 | #endif /* SQLITE_OMIT_UPSERT */ | 
 |           { | 
 | #ifndef SQLITE_OMIT_TRIGGER | 
 |             if( iCol<0 ){ | 
 |               pExpr->affExpr = 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->y.pTab = pTab; | 
 |             pExpr->iColumn = (i16)iCol; | 
 |             eNewExprOp = TK_TRIGGER; | 
 | #endif /* SQLITE_OMIT_TRIGGER */ | 
 |           } | 
 |         } | 
 |       } | 
 |     } | 
 | #endif /* !defined(SQLITE_OMIT_TRIGGER) || !defined(SQLITE_OMIT_UPSERT) */ | 
 |  | 
 |     /* | 
 |     ** Perhaps the name is a reference to the ROWID | 
 |     */ | 
 |     if( cnt==0 | 
 |      && cntTab==1 | 
 |      && pMatch | 
 |      && (pNC->ncFlags & (NC_IdxExpr|NC_GenCol))==0 | 
 |      && sqlite3IsRowid(zCol) | 
 |      && VisibleRowid(pMatch->pTab) | 
 |     ){ | 
 |       cnt = 1; | 
 |       pExpr->iColumn = -1; | 
 |       pExpr->affExpr = 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( (pNC->ncFlags & NC_UEList)!=0 | 
 |      && cnt==0 | 
 |      && zTab==0 | 
 |     ){ | 
 |       pEList = pNC->uNC.pEList; | 
 |       assert( pEList!=0 ); | 
 |       for(j=0; j<pEList->nExpr; j++){ | 
 |         char *zAs = pEList->a[j].zEName; | 
 |         if( pEList->a[j].eEName==ENAME_NAME | 
 |          && sqlite3_stricmp(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; | 
 |           } | 
 |           if( ExprHasProperty(pOrig, EP_Win) | 
 |            && ((pNC->ncFlags&NC_AllowWin)==0 || pNC!=pTopNC ) | 
 |           ){ | 
 |             sqlite3ErrorMsg(pParse, "misuse of aliased window function %s",zAs); | 
 |             return WRC_Abort; | 
 |           } | 
 |           if( sqlite3ExprVectorSize(pOrig)!=1 ){ | 
 |             sqlite3ErrorMsg(pParse, "row value misused"); | 
 |             return WRC_Abort; | 
 |           } | 
 |           resolveAlias(pParse, pEList, j, pExpr, "", nSubquery); | 
 |           cnt = 1; | 
 |           pMatch = 0; | 
 |           assert( zTab==0 && zDb==0 ); | 
 |           if( IN_RENAME_OBJECT ){ | 
 |             sqlite3RenameTokenRemap(pParse, 0, (void*)pExpr); | 
 |           } | 
 |           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 ) break; | 
 |     pNC = pNC->pNext; | 
 |     nSubquery++; | 
 |   }while( pNC ); | 
 |  | 
 |  | 
 |   /* | 
 |   ** 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 ){ | 
 |     assert( pExpr->op==TK_ID ); | 
 |     if( ExprHasProperty(pExpr,EP_DblQuoted) | 
 |      && areDoubleQuotedStringsEnabled(db, pTopNC) | 
 |     ){ | 
 |       /* If a double-quoted identifier does not match any known column name, | 
 |       ** then treat it as a string. | 
 |       ** | 
 |       ** This hack was added in the early days of SQLite in a misguided attempt | 
 |       ** to be compatible with MySQL 3.x, which used double-quotes for strings. | 
 |       ** I now sorely regret putting in this hack. The effect of this hack is | 
 |       ** that misspelled identifier names are silently converted into strings | 
 |       ** rather than causing an error, to the frustration of countless | 
 |       ** programmers. To all those frustrated programmers, my apologies. | 
 |       ** | 
 |       ** Someday, I hope to get rid of this hack. Unfortunately there is | 
 |       ** a huge amount of legacy SQL that uses it. So for now, we just | 
 |       ** issue a warning. | 
 |       */ | 
 |       sqlite3_log(SQLITE_WARNING, | 
 |         "double-quoted string literal: \"%w\"", zCol); | 
 | #ifdef SQLITE_ENABLE_NORMALIZE | 
 |       sqlite3VdbeAddDblquoteStr(db, pParse->pVdbe, zCol); | 
 | #endif | 
 |       pExpr->op = TK_STRING; | 
 |       pExpr->y.pTab = 0; | 
 |       return WRC_Prune; | 
 |     } | 
 |     if( sqlite3ExprIdToTrueFalse(pExpr) ){ | 
 |       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.  Bit 63 is | 
 |   ** set if the 63rd or any subsequent column is used. | 
 |   ** | 
 |   ** The colUsed mask is an optimization used to help determine if an | 
 |   ** index is a covering index.  The correct answer is still obtained | 
 |   ** if the mask contains extra set bits.  However, it is important to | 
 |   ** avoid setting bits beyond the maximum column number of the table. | 
 |   ** (See ticket [b92e5e8ec2cdbaa1]). | 
 |   ** | 
 |   ** If a generated column is referenced, set bits for every column | 
 |   ** of the table. | 
 |   */ | 
 |   if( pExpr->iColumn>=0 && pMatch!=0 ){ | 
 |     pMatch->colUsed |= sqlite3ExprColUsed(pExpr); | 
 |   } | 
 |  | 
 |   /* Clean up and return | 
 |   */ | 
 |   sqlite3ExprDelete(db, pExpr->pLeft); | 
 |   pExpr->pLeft = 0; | 
 |   sqlite3ExprDelete(db, pExpr->pRight); | 
 |   pExpr->pRight = 0; | 
 |   pExpr->op = eNewExprOp; | 
 |   ExprSetProperty(pExpr, EP_Leaf); | 
 | 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]; | 
 |     Table *pTab = p->y.pTab = pItem->pTab; | 
 |     p->iTable = pItem->iCursor; | 
 |     if( p->y.pTab->iPKey==iCol ){ | 
 |       p->iColumn = -1; | 
 |     }else{ | 
 |       p->iColumn = (ynVar)iCol; | 
 |       if( (pTab->tabFlags & TF_HasGenerated)!=0 | 
 |        && (pTab->aCol[iCol].colFlags & COLFLAG_GENERATED)!=0 | 
 |       ){ | 
 |         testcase( pTab->nCol==63 ); | 
 |         testcase( pTab->nCol==64 ); | 
 |         pItem->colUsed = pTab->nCol>=64 ? ALLBITS : MASKBIT(pTab->nCol)-1; | 
 |       }else{ | 
 |         testcase( iCol==BMS ); | 
 |         testcase( iCol==BMS-1 ); | 
 |         pItem->colUsed |= ((Bitmask)1)<<(iCol>=BMS ? BMS-1 : iCol); | 
 |       } | 
 |     } | 
 |   } | 
 |   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 | 
 | **   Expr *pExpr          // Invalidate this expression on error | 
 | ** ){...} | 
 | ** | 
 | ** As an optimization, since the conditional is almost always false | 
 | ** (because errors are rare), the conditional is moved outside of the | 
 | ** function call using a macro. | 
 | */ | 
 | static void notValidImpl( | 
 |    Parse *pParse,       /* Leave error message here */ | 
 |    NameContext *pNC,    /* The name context */ | 
 |    const char *zMsg,    /* Type of error */ | 
 |    Expr *pExpr          /* Invalidate this expression on error */ | 
 | ){ | 
 |   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 | 
 | #ifndef SQLITE_OMIT_GENERATED_COLUMNS | 
 |   else if( pNC->ncFlags & NC_GenCol ) zIn = "generated columns"; | 
 | #endif | 
 |   sqlite3ErrorMsg(pParse, "%s prohibited in %s", zMsg, zIn); | 
 |   if( pExpr ) pExpr->op = TK_NULL; | 
 | } | 
 | #define sqlite3ResolveNotValid(P,N,M,X,E) \ | 
 |   assert( ((X)&~(NC_IsCheck|NC_PartIdx|NC_IdxExpr|NC_GenCol))==0 ); \ | 
 |   if( ((N)->ncFlags & (X))!=0 ) notValidImpl(P,N,M,E); | 
 |  | 
 | /* | 
 | ** 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 ); | 
 |  | 
 | #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 ){ | 
 |  | 
 |     /* 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, and by  | 
 |     ** UPDATE ... FROM statement processing. | 
 |     */ | 
 |     case TK_ROW: { | 
 |       SrcList *pSrcList = pNC->pSrcList; | 
 |       struct SrcList_item *pItem; | 
 |       assert( pSrcList && pSrcList->nSrc>=1 ); | 
 |       pItem = pSrcList->a; | 
 |       pExpr->op = TK_COLUMN; | 
 |       pExpr->y.pTab = pItem->pTab; | 
 |       pExpr->iTable = pItem->iCursor; | 
 |       pExpr->iColumn--; | 
 |       pExpr->affExpr = SQLITE_AFF_INTEGER; | 
 |       break; | 
 |     } | 
 |  | 
 |     /* A column name:                    ID | 
 |     ** Or table name and column name:    ID.ID | 
 |     ** Or a database, table and column:  ID.ID.ID | 
 |     ** | 
 |     ** The TK_ID and TK_OUT cases are combined so that there will only | 
 |     ** be one call to lookupName().  Then the compiler will in-line  | 
 |     ** lookupName() for a size reduction and performance increase. | 
 |     */ | 
 |     case TK_ID: | 
 |     case TK_DOT: { | 
 |       const char *zColumn; | 
 |       const char *zTable; | 
 |       const char *zDb; | 
 |       Expr *pRight; | 
 |  | 
 |       if( pExpr->op==TK_ID ){ | 
 |         zDb = 0; | 
 |         zTable = 0; | 
 |         zColumn = pExpr->u.zToken; | 
 |       }else{ | 
 |         Expr *pLeft = pExpr->pLeft; | 
 |         testcase( pNC->ncFlags & NC_IdxExpr ); | 
 |         testcase( pNC->ncFlags & NC_GenCol ); | 
 |         sqlite3ResolveNotValid(pParse, pNC, "the \".\" operator", | 
 |                                NC_IdxExpr|NC_GenCol, 0); | 
 |         pRight = pExpr->pRight; | 
 |         if( pRight->op==TK_ID ){ | 
 |           zDb = 0; | 
 |         }else{ | 
 |           assert( pRight->op==TK_DOT ); | 
 |           zDb = pLeft->u.zToken; | 
 |           pLeft = pRight->pLeft; | 
 |           pRight = pRight->pRight; | 
 |         } | 
 |         zTable = pLeft->u.zToken; | 
 |         zColumn = pRight->u.zToken; | 
 |         if( IN_RENAME_OBJECT ){ | 
 |           sqlite3RenameTokenRemap(pParse, (void*)pExpr, (void*)pRight); | 
 |           sqlite3RenameTokenRemap(pParse, (void*)&pExpr->y.pTab, (void*)pLeft); | 
 |         } | 
 |       } | 
 |       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 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 */ | 
 |       int savedAllowFlags = (pNC->ncFlags & (NC_AllowAgg | NC_AllowWin)); | 
 | #ifndef SQLITE_OMIT_WINDOWFUNC | 
 |       Window *pWin = (IsWindowFunc(pExpr) ? pExpr->y.pWin : 0); | 
 | #endif | 
 |       assert( !ExprHasProperty(pExpr, EP_xIsSelect) ); | 
 |       zId = pExpr->u.zToken; | 
 |       nId = sqlite3Strlen30(zId); | 
 |       pDef = sqlite3FindFunction(pParse->db, zId, n, enc, 0); | 
 |       if( pDef==0 ){ | 
 |         pDef = sqlite3FindFunction(pParse->db, zId, -2, enc, 0); | 
 |         if( pDef==0 ){ | 
 |           no_such_func = 1; | 
 |         }else{ | 
 |           wrong_num_args = 1; | 
 |         } | 
 |       }else{ | 
 |         is_agg = pDef->xFinalize!=0; | 
 |         if( pDef->funcFlags & SQLITE_FUNC_UNLIKELY ){ | 
 |           ExprSetProperty(pExpr, EP_Unlikely); | 
 |           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 | 
 |         { | 
 |           int 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. | 
 |           ** This allows them to be factored out of inner loops. */ | 
 |           ExprSetProperty(pExpr,EP_ConstFunc); | 
 |         } | 
 |         if( (pDef->funcFlags & SQLITE_FUNC_CONSTANT)==0 ){ | 
 |           /* Clearly non-deterministic functions like random(), but also | 
 |           ** date/time functions that use 'now', and other functions like | 
 |           ** sqlite_version() that might change over time cannot be used | 
 |           ** in an index or generated column.  Curiously, they can be used | 
 |           ** in a CHECK constraint.  SQLServer, MySQL, and PostgreSQL all | 
 |           ** all this. */ | 
 |           sqlite3ResolveNotValid(pParse, pNC, "non-deterministic functions", | 
 |                                  NC_IdxExpr|NC_PartIdx|NC_GenCol, 0); | 
 |         }else{ | 
 |           assert( (NC_SelfRef & 0xff)==NC_SelfRef ); /* Must fit in 8 bits */ | 
 |           pExpr->op2 = pNC->ncFlags & NC_SelfRef; | 
 |           if( pNC->ncFlags & NC_FromDDL ) ExprSetProperty(pExpr, EP_FromDDL); | 
 |         } | 
 |         if( (pDef->funcFlags & SQLITE_FUNC_INTERNAL)!=0 | 
 |          && pParse->nested==0 | 
 |          && (pParse->db->mDbFlags & DBFLAG_InternalFunc)==0 | 
 |         ){ | 
 |           /* Internal-use-only functions are disallowed unless the | 
 |           ** SQL is being compiled using sqlite3NestedParse() or | 
 |           ** the SQLITE_TESTCTRL_INTERNAL_FUNCTIONS test-control has be | 
 |           ** used to activate internal functions for testing purposes */ | 
 |           no_such_func = 1; | 
 |           pDef = 0; | 
 |         }else | 
 |         if( (pDef->funcFlags & (SQLITE_FUNC_DIRECT|SQLITE_FUNC_UNSAFE))!=0 | 
 |          && !IN_RENAME_OBJECT | 
 |         ){ | 
 |           sqlite3ExprFunctionUsable(pParse, pExpr, pDef); | 
 |         } | 
 |       } | 
 |  | 
 |       if( 0==IN_RENAME_OBJECT ){ | 
 | #ifndef SQLITE_OMIT_WINDOWFUNC | 
 |         assert( is_agg==0 || (pDef->funcFlags & SQLITE_FUNC_MINMAX) | 
 |           || (pDef->xValue==0 && pDef->xInverse==0) | 
 |           || (pDef->xValue && pDef->xInverse && pDef->xSFunc && pDef->xFinalize) | 
 |         ); | 
 |         if( pDef && pDef->xValue==0 && pWin ){ | 
 |           sqlite3ErrorMsg(pParse,  | 
 |               "%.*s() may not be used as a window function", nId, zId | 
 |           ); | 
 |           pNC->nErr++; | 
 |         }else if(  | 
 |               (is_agg && (pNC->ncFlags & NC_AllowAgg)==0) | 
 |            || (is_agg && (pDef->funcFlags&SQLITE_FUNC_WINDOW) && !pWin) | 
 |            || (is_agg && pWin && (pNC->ncFlags & NC_AllowWin)==0) | 
 |         ){ | 
 |           const char *zType; | 
 |           if( (pDef->funcFlags & SQLITE_FUNC_WINDOW) || pWin ){ | 
 |             zType = "window"; | 
 |           }else{ | 
 |             zType = "aggregate"; | 
 |           } | 
 |           sqlite3ErrorMsg(pParse, "misuse of %s function %.*s()",zType,nId,zId); | 
 |           pNC->nErr++; | 
 |           is_agg = 0; | 
 |         } | 
 | #else | 
 |         if( (is_agg && (pNC->ncFlags & NC_AllowAgg)==0) ){ | 
 |           sqlite3ErrorMsg(pParse,"misuse of aggregate function %.*s()",nId,zId); | 
 |           pNC->nErr++; | 
 |           is_agg = 0; | 
 |         } | 
 | #endif | 
 |         else if( no_such_func && pParse->db->init.busy==0 | 
 | #ifdef SQLITE_ENABLE_UNKNOWN_SQL_FUNCTION | 
 |                   && pParse->explain==0 | 
 | #endif | 
 |         ){ | 
 |           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++; | 
 |         } | 
 | #ifndef SQLITE_OMIT_WINDOWFUNC | 
 |         else if( is_agg==0 && ExprHasProperty(pExpr, EP_WinFunc) ){ | 
 |           sqlite3ErrorMsg(pParse,  | 
 |               "FILTER may not be used with non-aggregate %.*s()",  | 
 |               nId, zId | 
 |           ); | 
 |           pNC->nErr++; | 
 |         } | 
 | #endif | 
 |         if( is_agg ){ | 
 |           /* Window functions may not be arguments of aggregate functions. | 
 |           ** Or arguments of other window functions. But aggregate functions | 
 |           ** may be arguments for window functions.  */ | 
 | #ifndef SQLITE_OMIT_WINDOWFUNC | 
 |           pNC->ncFlags &= ~(NC_AllowWin | (!pWin ? NC_AllowAgg : 0)); | 
 | #else | 
 |           pNC->ncFlags &= ~NC_AllowAgg; | 
 | #endif | 
 |         } | 
 |       } | 
 | #ifndef SQLITE_OMIT_WINDOWFUNC | 
 |       else if( ExprHasProperty(pExpr, EP_WinFunc) ){ | 
 |         is_agg = 1; | 
 |       } | 
 | #endif | 
 |       sqlite3WalkExprList(pWalker, pList); | 
 |       if( is_agg ){ | 
 | #ifndef SQLITE_OMIT_WINDOWFUNC | 
 |         if( pWin ){ | 
 |           Select *pSel = pNC->pWinSelect; | 
 |           assert( pWin==pExpr->y.pWin ); | 
 |           if( IN_RENAME_OBJECT==0 ){ | 
 |             sqlite3WindowUpdate(pParse, pSel ? pSel->pWinDefn : 0, pWin, pDef); | 
 |           } | 
 |           sqlite3WalkExprList(pWalker, pWin->pPartition); | 
 |           sqlite3WalkExprList(pWalker, pWin->pOrderBy); | 
 |           sqlite3WalkExpr(pWalker, pWin->pFilter); | 
 |           sqlite3WindowLink(pSel, pWin); | 
 |           pNC->ncFlags |= NC_HasWin; | 
 |         }else | 
 | #endif /* SQLITE_OMIT_WINDOWFUNC */ | 
 |         { | 
 |           NameContext *pNC2 = pNC; | 
 |           pExpr->op = TK_AGG_FUNCTION; | 
 |           pExpr->op2 = 0; | 
 | #ifndef SQLITE_OMIT_WINDOWFUNC | 
 |           if( ExprHasProperty(pExpr, EP_WinFunc) ){ | 
 |             sqlite3WalkExpr(pWalker, pExpr->y.pWin->pFilter); | 
 |           } | 
 | #endif | 
 |           while( pNC2 && !sqlite3FunctionUsesThisSrc(pExpr, pNC2->pSrcList) ){ | 
 |             pExpr->op2++; | 
 |             pNC2 = pNC2->pNext; | 
 |           } | 
 |           assert( pDef!=0 || IN_RENAME_OBJECT ); | 
 |           if( pNC2 && pDef ){ | 
 |             assert( SQLITE_FUNC_MINMAX==NC_MinMaxAgg ); | 
 |             testcase( (pDef->funcFlags & SQLITE_FUNC_MINMAX)!=0 ); | 
 |             pNC2->ncFlags |= NC_HasAgg | (pDef->funcFlags & SQLITE_FUNC_MINMAX); | 
 |  | 
 |           } | 
 |         } | 
 |         pNC->ncFlags |= savedAllowFlags; | 
 |       } | 
 |       /* 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; | 
 |         testcase( pNC->ncFlags & NC_IsCheck ); | 
 |         testcase( pNC->ncFlags & NC_PartIdx ); | 
 |         testcase( pNC->ncFlags & NC_IdxExpr ); | 
 |         testcase( pNC->ncFlags & NC_GenCol ); | 
 |         sqlite3ResolveNotValid(pParse, pNC, "subqueries", | 
 |                  NC_IsCheck|NC_PartIdx|NC_IdxExpr|NC_GenCol, pExpr); | 
 |         sqlite3WalkSelect(pWalker, pExpr->x.pSelect); | 
 |         assert( pNC->nRef>=nRef ); | 
 |         if( nRef!=pNC->nRef ){ | 
 |           ExprSetProperty(pExpr, EP_VarSelect); | 
 |           pNC->ncFlags |= NC_VarSelect; | 
 |         } | 
 |       } | 
 |       break; | 
 |     } | 
 |     case TK_VARIABLE: { | 
 |       testcase( pNC->ncFlags & NC_IsCheck ); | 
 |       testcase( pNC->ncFlags & NC_PartIdx ); | 
 |       testcase( pNC->ncFlags & NC_IdxExpr ); | 
 |       testcase( pNC->ncFlags & NC_GenCol ); | 
 |       sqlite3ResolveNotValid(pParse, pNC, "parameters", | 
 |                NC_IsCheck|NC_PartIdx|NC_IdxExpr|NC_GenCol, pExpr); | 
 |       break; | 
 |     } | 
 |     case TK_IS: | 
 |     case TK_ISNOT: { | 
 |       Expr *pRight = sqlite3ExprSkipCollateAndLikely(pExpr->pRight); | 
 |       assert( !ExprHasProperty(pExpr, EP_Reduced) ); | 
 |       /* Handle special cases of "x IS TRUE", "x IS FALSE", "x IS NOT TRUE", | 
 |       ** and "x IS NOT FALSE". */ | 
 |       if( pRight && pRight->op==TK_ID ){ | 
 |         int rc = resolveExprStep(pWalker, pRight); | 
 |         if( rc==WRC_Abort ) return WRC_Abort; | 
 |         if( pRight->op==TK_TRUEFALSE ){ | 
 |           pExpr->op2 = pExpr->op; | 
 |           pExpr->op = TK_TRUTH; | 
 |           return WRC_Continue; | 
 |         } | 
 |       } | 
 |       /* Fall thru */ | 
 |     } | 
 |     case TK_BETWEEN: | 
 |     case TK_EQ: | 
 |     case TK_NE: | 
 |     case TK_LT: | 
 |     case TK_LE: | 
 |     case TK_GT: | 
 |     case TK_GE: { | 
 |       int nLeft, nRight; | 
 |       if( pParse->db->mallocFailed ) break; | 
 |       assert( pExpr->pLeft!=0 ); | 
 |       nLeft = sqlite3ExprVectorSize(pExpr->pLeft); | 
 |       if( pExpr->op==TK_BETWEEN ){ | 
 |         nRight = sqlite3ExprVectorSize(pExpr->x.pList->a[0].pExpr); | 
 |         if( nRight==nLeft ){ | 
 |           nRight = sqlite3ExprVectorSize(pExpr->x.pList->a[1].pExpr); | 
 |         } | 
 |       }else{ | 
 |         assert( pExpr->pRight!=0 ); | 
 |         nRight = sqlite3ExprVectorSize(pExpr->pRight); | 
 |       } | 
 |       if( nLeft!=nRight ){ | 
 |         testcase( pExpr->op==TK_EQ ); | 
 |         testcase( pExpr->op==TK_NE ); | 
 |         testcase( pExpr->op==TK_LT ); | 
 |         testcase( pExpr->op==TK_LE ); | 
 |         testcase( pExpr->op==TK_GT ); | 
 |         testcase( pExpr->op==TK_GE ); | 
 |         testcase( pExpr->op==TK_IS ); | 
 |         testcase( pExpr->op==TK_ISNOT ); | 
 |         testcase( pExpr->op==TK_BETWEEN ); | 
 |         sqlite3ErrorMsg(pParse, "row value misused"); | 
 |       } | 
 |       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++){ | 
 |       if( pEList->a[i].eEName==ENAME_NAME | 
 |        && sqlite3_stricmp(pEList->a[i].zEName, 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.uNC.pEList = pEList; | 
 |   nc.ncFlags = NC_AllowAgg|NC_UEList; | 
 |   nc.nErr = 0; | 
 |   db = pParse->db; | 
 |   savedSuppErr = db->suppressErr; | 
 |   if( IN_RENAME_OBJECT==0 ) 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(0, 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( pOrderBy->nExpr>db->aLimit[SQLITE_LIMIT_COLUMN] ){ | 
 |     sqlite3ErrorMsg(pParse, "too many terms in ORDER BY clause"); | 
 |     return 1; | 
 |   } | 
 |   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 = sqlite3ExprSkipCollateAndLikely(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 ){ | 
 |           /* Now test if expression pE matches one of the values returned | 
 |           ** by pSelect. In the usual case this is done by duplicating the  | 
 |           ** expression, resolving any symbols in it, and then comparing | 
 |           ** it against each expression returned by the SELECT statement. | 
 |           ** Once the comparisons are finished, the duplicate expression | 
 |           ** is deleted. | 
 |           ** | 
 |           ** Or, if this is running as part of an ALTER TABLE operation, | 
 |           ** resolve the symbols in the actual expression, not a duplicate. | 
 |           ** And, if one of the comparisons is successful, leave the expression | 
 |           ** as is instead of transforming it to an integer as in the usual | 
 |           ** case. This allows the code in alter.c to modify column | 
 |           ** references within the ORDER BY expression as required.  */ | 
 |           if( IN_RENAME_OBJECT ){ | 
 |             pDup = pE; | 
 |           }else{ | 
 |             pDup = sqlite3ExprDup(db, pE, 0); | 
 |           } | 
 |           if( !db->mallocFailed ){ | 
 |             assert(pDup); | 
 |             iCol = resolveOrderByTermToExprList(pParse, pSelect, pDup); | 
 |           } | 
 |           if( !IN_RENAME_OBJECT ){ | 
 |             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 */ | 
 |         if( !IN_RENAME_OBJECT ){ | 
 |           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 || IN_RENAME_OBJECT ) return 0; | 
 |   if( pOrderBy->nExpr>db->aLimit[SQLITE_LIMIT_COLUMN] ){ | 
 |     sqlite3ErrorMsg(pParse, "too many terms in %s BY clause", zType); | 
 |     return 1; | 
 |   } | 
 |   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; | 
 | } | 
 |  | 
 | #ifndef SQLITE_OMIT_WINDOWFUNC | 
 | /* | 
 | ** Walker callback for windowRemoveExprFromSelect(). | 
 | */ | 
 | static int resolveRemoveWindowsCb(Walker *pWalker, Expr *pExpr){ | 
 |   UNUSED_PARAMETER(pWalker); | 
 |   if( ExprHasProperty(pExpr, EP_WinFunc) ){ | 
 |     Window *pWin = pExpr->y.pWin; | 
 |     sqlite3WindowUnlinkFromSelect(pWin); | 
 |   } | 
 |   return WRC_Continue; | 
 | } | 
 |  | 
 | /* | 
 | ** Remove any Window objects owned by the expression pExpr from the | 
 | ** Select.pWin list of Select object pSelect. | 
 | */ | 
 | static void windowRemoveExprFromSelect(Select *pSelect, Expr *pExpr){ | 
 |   if( pSelect->pWin ){ | 
 |     Walker sWalker; | 
 |     memset(&sWalker, 0, sizeof(Walker)); | 
 |     sWalker.xExprCallback = resolveRemoveWindowsCb; | 
 |     sWalker.u.pSelect = pSelect; | 
 |     sqlite3WalkExpr(&sWalker, pExpr); | 
 |   } | 
 | } | 
 | #else | 
 | # define windowRemoveExprFromSelect(a, b) | 
 | #endif /* SQLITE_OMIT_WINDOWFUNC */ | 
 |  | 
 | /* | 
 | ** 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 = sqlite3ExprSkipCollateAndLikely(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(0, pE, pSelect->pEList->a[j].pExpr, -1)==0 ){ | 
 |         /* Since this expression is being changed into a reference | 
 |         ** to an identical expression in the result set, remove all Window | 
 |         ** objects belonging to the expression from the Select.pWin list. */ | 
 |         windowRemoveExprFromSelect(pSelect, pE); | 
 |         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; | 
 |     sNC.pWinSelect = p; | 
 |     if( sqlite3ResolveExprNames(&sNC, p->pLimit) ){ | 
 |       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 && (pItem->pSelect->selFlags & SF_Resolved)==0 ){ | 
 |         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|NC_AllowWin; | 
 |     sNC.pSrcList = p->pSrc; | 
 |     sNC.pNext = pOuterNC; | 
 |    | 
 |     /* Resolve names in the result set. */ | 
 |     if( sqlite3ResolveExprListNames(&sNC, p->pEList) ) return WRC_Abort; | 
 |     sNC.ncFlags &= ~NC_AllowWin; | 
 |    | 
 |     /* 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. | 
 |     */ | 
 |     assert( (sNC.ncFlags & (NC_UAggInfo|NC_UUpsert))==0 ); | 
 |     sNC.uNC.pEList = p->pEList; | 
 |     sNC.ncFlags |= NC_UEList; | 
 |     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|NC_AllowWin; | 
 |  | 
 |     /* 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; | 
 |     } | 
 |     sNC.ncFlags &= ~NC_AllowWin; | 
 |    | 
 |     /* 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; | 
 |         } | 
 |       } | 
 |     } | 
 |  | 
 | #ifndef SQLITE_OMIT_WINDOWFUNC | 
 |     if( IN_RENAME_OBJECT ){ | 
 |       Window *pWin; | 
 |       for(pWin=p->pWinDefn; pWin; pWin=pWin->pNextWin){ | 
 |         if( sqlite3ResolveExprListNames(&sNC, pWin->pOrderBy) | 
 |          || sqlite3ResolveExprListNames(&sNC, pWin->pPartition) | 
 |         ){ | 
 |           return WRC_Abort; | 
 |         } | 
 |       } | 
 |     } | 
 | #endif | 
 |  | 
 |     /* 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. */ | 
 | ){ | 
 |   int savedHasAgg; | 
 |   Walker w; | 
 |  | 
 |   if( pExpr==0 ) return SQLITE_OK; | 
 |   savedHasAgg = pNC->ncFlags & (NC_HasAgg|NC_MinMaxAgg|NC_HasWin); | 
 |   pNC->ncFlags &= ~(NC_HasAgg|NC_MinMaxAgg|NC_HasWin); | 
 |   w.pParse = pNC->pParse; | 
 |   w.xExprCallback = resolveExprStep; | 
 |   w.xSelectCallback = resolveSelectStep; | 
 |   w.xSelectCallback2 = 0; | 
 |   w.u.pNC = pNC; | 
 | #if SQLITE_MAX_EXPR_DEPTH>0 | 
 |   w.pParse->nHeight += pExpr->nHeight; | 
 |   if( sqlite3ExprCheckHeight(w.pParse, w.pParse->nHeight) ){ | 
 |     return SQLITE_ERROR; | 
 |   } | 
 | #endif | 
 |   sqlite3WalkExpr(&w, pExpr); | 
 | #if SQLITE_MAX_EXPR_DEPTH>0 | 
 |   w.pParse->nHeight -= pExpr->nHeight; | 
 | #endif | 
 |   assert( EP_Agg==NC_HasAgg ); | 
 |   assert( EP_Win==NC_HasWin ); | 
 |   testcase( pNC->ncFlags & NC_HasAgg ); | 
 |   testcase( pNC->ncFlags & NC_HasWin ); | 
 |   ExprSetProperty(pExpr, pNC->ncFlags & (NC_HasAgg|NC_HasWin) ); | 
 |   pNC->ncFlags |= savedHasAgg; | 
 |   return pNC->nErr>0 || w.pParse->nErr>0; | 
 | } | 
 |  | 
 | /* | 
 | ** 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; | 
 |   int savedHasAgg = 0; | 
 |   Walker w; | 
 |   if( pList==0 ) return WRC_Continue; | 
 |   w.pParse = pNC->pParse; | 
 |   w.xExprCallback = resolveExprStep; | 
 |   w.xSelectCallback = resolveSelectStep; | 
 |   w.xSelectCallback2 = 0; | 
 |   w.u.pNC = pNC; | 
 |   savedHasAgg = pNC->ncFlags & (NC_HasAgg|NC_MinMaxAgg|NC_HasWin); | 
 |   pNC->ncFlags &= ~(NC_HasAgg|NC_MinMaxAgg|NC_HasWin); | 
 |   for(i=0; i<pList->nExpr; i++){ | 
 |     Expr *pExpr = pList->a[i].pExpr; | 
 |     if( pExpr==0 ) continue; | 
 | #if SQLITE_MAX_EXPR_DEPTH>0 | 
 |     w.pParse->nHeight += pExpr->nHeight; | 
 |     if( sqlite3ExprCheckHeight(w.pParse, w.pParse->nHeight) ){ | 
 |       return WRC_Abort; | 
 |     } | 
 | #endif | 
 |     sqlite3WalkExpr(&w, pExpr); | 
 | #if SQLITE_MAX_EXPR_DEPTH>0 | 
 |     w.pParse->nHeight -= pExpr->nHeight; | 
 | #endif | 
 |     assert( EP_Agg==NC_HasAgg ); | 
 |     assert( EP_Win==NC_HasWin ); | 
 |     testcase( pNC->ncFlags & NC_HasAgg ); | 
 |     testcase( pNC->ncFlags & NC_HasWin ); | 
 |     if( pNC->ncFlags & (NC_HasAgg|NC_MinMaxAgg|NC_HasWin) ){ | 
 |       ExprSetProperty(pExpr, pNC->ncFlags & (NC_HasAgg|NC_HasWin) ); | 
 |       savedHasAgg |= pNC->ncFlags & (NC_HasAgg|NC_MinMaxAgg|NC_HasWin); | 
 |       pNC->ncFlags &= ~(NC_HasAgg|NC_MinMaxAgg|NC_HasWin); | 
 |     } | 
 |     if( pNC->nErr>0 || w.pParse->nErr>0 ) return WRC_Abort; | 
 |   } | 
 |   pNC->ncFlags |= savedHasAgg; | 
 |   return WRC_Continue; | 
 | } | 
 |  | 
 | /* | 
 | ** Resolve all names in all expressions of a SELECT and in all | 
 | ** descendents 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 ); | 
 |   w.xExprCallback = resolveExprStep; | 
 |   w.xSelectCallback = resolveSelectStep; | 
 |   w.xSelectCallback2 = 0; | 
 |   w.pParse = pParse; | 
 |   w.u.pNC = pOuterNC; | 
 |   sqlite3WalkSelect(&w, p); | 
 | } | 
 |  | 
 | /* | 
 | ** Resolve names in expressions that can only reference a single table | 
 | ** or which cannot reference any tables at all.  Examples: | 
 | ** | 
 | **                                                    "type" flag | 
 | **                                                    ------------ | 
 | **    (1)   CHECK constraints                         NC_IsCheck | 
 | **    (2)   WHERE clauses on partial indices          NC_PartIdx | 
 | **    (3)   Expressions in indexes on expressions     NC_IdxExpr | 
 | **    (4)   Expression arguments to VACUUM INTO.      0 | 
 | **    (5)   GENERATED ALWAYS as expressions           NC_GenCol | 
 | ** | 
 | ** In all cases except (4), 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.  In case (4), TK_COLUMN nodes cause an error. | 
 | ** | 
 | ** Any errors cause an error message to be set in pParse. | 
 | */ | 
 | int sqlite3ResolveSelfReference( | 
 |   Parse *pParse,   /* Parsing context */ | 
 |   Table *pTab,     /* The table being referenced, or NULL */ | 
 |   int type,        /* NC_IsCheck, NC_PartIdx, NC_IdxExpr, NC_GenCol, or 0 */ | 
 |   Expr *pExpr,     /* Expression to resolve.  May be NULL. */ | 
 |   ExprList *pList  /* Expression list to resolve.  May be NULL. */ | 
 | ){ | 
 |   SrcList sSrc;                   /* Fake SrcList for pParse->pNewTable */ | 
 |   NameContext sNC;                /* Name context for pParse->pNewTable */ | 
 |   int rc; | 
 |  | 
 |   assert( type==0 || pTab!=0 ); | 
 |   assert( type==NC_IsCheck || type==NC_PartIdx || type==NC_IdxExpr | 
 |           || type==NC_GenCol || pTab==0 ); | 
 |   memset(&sNC, 0, sizeof(sNC)); | 
 |   memset(&sSrc, 0, sizeof(sSrc)); | 
 |   if( pTab ){ | 
 |     sSrc.nSrc = 1; | 
 |     sSrc.a[0].zName = pTab->zName; | 
 |     sSrc.a[0].pTab = pTab; | 
 |     sSrc.a[0].iCursor = -1; | 
 |     if( pTab->pSchema!=pParse->db->aDb[1].pSchema ){ | 
 |       /* Cause EP_FromDDL to be set on TK_FUNCTION nodes of non-TEMP | 
 |       ** schema elements */ | 
 |       type |= NC_FromDDL; | 
 |     } | 
 |   } | 
 |   sNC.pParse = pParse; | 
 |   sNC.pSrcList = &sSrc; | 
 |   sNC.ncFlags = type | NC_IsDDL; | 
 |   if( (rc = sqlite3ResolveExprNames(&sNC, pExpr))!=SQLITE_OK ) return rc; | 
 |   if( pList ) rc = sqlite3ResolveExprListNames(&sNC, pList); | 
 |   return rc; | 
 | } |