Adding upstream version 3.40.1.upstream/3.40.1upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 2135 insertions, 0 deletions

diff --git a/src/resolve.c b/src/resolve.c
new file mode 100644
index 0000000..1c3a9d9
--- /dev/null
+++ b/src/resolve.c
@@ -0,0 +1,2135 @@
+/*
+** 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 */
+  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( db->mallocFailed ){
+    sqlite3ExprDelete(db, pDup);
+    pDup = 0;
+  }else{
+    Expr temp;
+    incrAggFunctionDepth(pDup, nSubquery);
+    if( pExpr->op==TK_COLLATE ){
+      assert( !ExprHasProperty(pExpr, EP_IntValue) );
+      pDup = sqlite3ExprAddCollateString(pParse, pDup, pExpr->u.zToken);
+    }
+    memcpy(&temp, pDup, sizeof(Expr));
+    memcpy(pDup, pExpr, sizeof(Expr));
+    memcpy(pExpr, &temp, sizeof(Expr));
+    if( ExprHasProperty(pExpr, EP_WinFunc) ){
+      if( ALWAYS(pExpr->y.pWin!=0) ){
+        pExpr->y.pWin->pOwner = pExpr;
+      }
+    }
+    sqlite3ExprDeferredDelete(pParse, pDup);
+  }
+}
+
+/*
+** 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->fg.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;
+  assert( ExprUseYTab(pExpr) );
+  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;
+  }
+}
+
+/*
+** Create a new expression term for the column specified by pMatch and
+** iColumn.  Append this new expression term to the FULL JOIN Match set
+** in *ppList.  Create a new *ppList if this is the first term in the
+** set.
+*/
+static void extendFJMatch(
+  Parse *pParse,          /* Parsing context */
+  ExprList **ppList,      /* ExprList to extend */
+  SrcItem *pMatch,        /* Source table containing the column */
+  i16 iColumn             /* The column number */
+){
+  Expr *pNew = sqlite3ExprAlloc(pParse->db, TK_COLUMN, 0, 0);
+  if( pNew ){
+    pNew->iTable = pMatch->iCursor;
+    pNew->iColumn = iColumn;
+    pNew->y.pTab = pMatch->pTab;
+    assert( (pMatch->fg.jointype & (JT_LEFT|JT_LTORJ))!=0 );
+    ExprSetProperty(pNew, EP_CanBeNull);
+    *ppList = sqlite3ExprListAppend(pParse, *ppList, pNew);
+  }
+}
+
+/*
+** 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 */
+  SrcItem *pItem;                   /* Use for looping over pSrcList items */
+  SrcItem *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 holding the row */
+  Column *pCol;                     /* A column of pTab */
+  ExprList *pFJMatch = 0;           /* Matches for FULL JOIN .. USING */
+
+  assert( pNC );     /* the name context cannot be NULL. */
+  assert( zCol );    /* The Z in X.Y.Z cannot be NULL */
+  assert( zDb==0 || zTab!=0 );
+  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 || pParse->nErr );
+        assert( (int)pItem->fg.isNestedFrom == IsNestedFrom(pItem->pSelect) );
+        if( pItem->fg.isNestedFrom ){
+          /* In this case, pItem is a subquery that has been formed from a
+          ** parenthesized subset of the FROM clause terms.  Example:
+          **   .... FROM t1 LEFT JOIN (t2 RIGHT JOIN t3 USING(x)) USING(y) ...
+          **                          \_________________________/
+          **             This pItem -------------^
+          */
+          int hit = 0;
+          assert( pItem->pSelect!=0 );
+          pEList = pItem->pSelect->pEList;
+          assert( pEList!=0 );
+          assert( pEList->nExpr==pTab->nCol );
+          for(j=0; j<pEList->nExpr; j++){
+            if( !sqlite3MatchEName(&pEList->a[j], zCol, zTab, zDb) ){
+              continue;
+            }
+            if( cnt>0 ){
+              if( pItem->fg.isUsing==0
+               || sqlite3IdListIndex(pItem->u3.pUsing, zCol)<0
+              ){
+                /* Two or more tables have the same column name which is
+                ** not joined by USING.  This is an error.  Signal as much
+                ** by clearing pFJMatch and letting cnt go above 1. */
+                sqlite3ExprListDelete(db, pFJMatch);
+                pFJMatch = 0;
+              }else
+              if( (pItem->fg.jointype & JT_RIGHT)==0 ){
+                /* An INNER or LEFT JOIN.  Use the left-most table */
+                continue;
+              }else
+              if( (pItem->fg.jointype & JT_LEFT)==0 ){
+                /* A RIGHT JOIN.  Use the right-most table */
+                cnt = 0;
+                sqlite3ExprListDelete(db, pFJMatch);
+                pFJMatch = 0;
+              }else{
+                /* For a FULL JOIN, we must construct a coalesce() func */
+                extendFJMatch(pParse, &pFJMatch, pMatch, pExpr->iColumn);
+              }
+            }
+            cnt++;
+            cntTab = 2;
+            pMatch = pItem;
+            pExpr->iColumn = j;
+            pEList->a[j].fg.bUsed = 1;
+            hit = 1;
+            if( pEList->a[j].fg.bUsingTerm ) break;
+          }
+          if( hit || zTab==0 ) continue;
+        }
+        assert( zDb==0 || zTab!=0 );
+        if( zTab ){
+          const char *zTabName;
+          if( zDb ){
+            if( pTab->pSchema!=pSchema ) continue;
+            if( pSchema==0 && strcmp(zDb,"*")!=0 ) continue;
+          }
+          zTabName = pItem->zAlias ? pItem->zAlias : pTab->zName;
+          assert( zTabName!=0 );
+          if( sqlite3StrICmp(zTabName, zTab)!=0 ){
+            continue;
+          }
+          assert( ExprUseYTab(pExpr) );
+          if( IN_RENAME_OBJECT && pItem->zAlias ){
+            sqlite3RenameTokenRemap(pParse, 0, (void*)&pExpr->y.pTab);
+          }
+        }
+        hCol = sqlite3StrIHash(zCol);
+        for(j=0, pCol=pTab->aCol; j<pTab->nCol; j++, pCol++){
+          if( pCol->hName==hCol
+           && sqlite3StrICmp(pCol->zCnName, zCol)==0
+          ){
+            if( cnt>0 ){
+              if( pItem->fg.isUsing==0
+               || sqlite3IdListIndex(pItem->u3.pUsing, zCol)<0
+              ){
+                /* Two or more tables have the same column name which is
+                ** not joined by USING.  This is an error.  Signal as much
+                ** by clearing pFJMatch and letting cnt go above 1. */
+                sqlite3ExprListDelete(db, pFJMatch);
+                pFJMatch = 0;
+              }else
+              if( (pItem->fg.jointype & JT_RIGHT)==0 ){
+                /* An INNER or LEFT JOIN.  Use the left-most table */
+                continue;
+              }else
+              if( (pItem->fg.jointype & JT_LEFT)==0 ){
+                /* A RIGHT JOIN.  Use the right-most table */
+                cnt = 0;
+                sqlite3ExprListDelete(db, pFJMatch);
+                pFJMatch = 0;
+              }else{
+                /* For a FULL JOIN, we must construct a coalesce() func */
+                extendFJMatch(pParse, &pFJMatch, pMatch, pExpr->iColumn);
+              }
+            }
+            cnt++;
+            pMatch = pItem;
+            /* Substitute the rowid (column -1) for the INTEGER PRIMARY KEY */
+            pExpr->iColumn = j==pTab->iPKey ? -1 : (i16)j;
+            if( pItem->fg.isNestedFrom ){
+              sqlite3SrcItemColumnUsed(pItem, j);
+            }
+            break;
+          }
+        }
+        if( 0==cnt && VisibleRowid(pTab) ){
+          cntTab++;
+          pMatch = pItem;
+        }
+      }
+      if( pMatch ){
+        pExpr->iTable = pMatch->iCursor;
+        assert( ExprUseYTab(pExpr) );
+        pExpr->y.pTab = pMatch->pTab;
+        if( (pMatch->fg.jointype & (JT_LEFT|JT_LTORJ))!=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.  Or maybe it is
+    ** a reference in the RETURNING clause to a table being modified.
+    */
+    if( cnt==0 && zDb==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( pParse->bReturning ){
+          if( (pNC->ncFlags & NC_UBaseReg)!=0
+           && (zTab==0 || sqlite3StrICmp(zTab,pParse->pTriggerTab->zName)==0)
+          ){
+            pExpr->iTable = op!=TK_DELETE;
+            pTab = pParse->pTriggerTab;
+          }
+        }else if( op!=TK_DELETE && zTab && sqlite3StrICmp("new",zTab) == 0 ){
+          pExpr->iTable = 1;
+          pTab = pParse->pTriggerTab;
+        }else if( op!=TK_INSERT && zTab && sqlite3StrICmp("old",zTab)==0 ){
+          pExpr->iTable = 0;
+          pTab = pParse->pTriggerTab;
+        }
+      }
+#endif /* SQLITE_OMIT_TRIGGER */
+#ifndef SQLITE_OMIT_UPSERT
+      if( (pNC->ncFlags & NC_UUpsert)!=0 && zTab!=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->zCnName, 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++;
+          pMatch = 0;
+#ifndef SQLITE_OMIT_UPSERT
+          if( pExpr->iTable==EXCLUDED_TABLE_NUMBER ){
+            testcase( iCol==(-1) );
+            assert( ExprUseYTab(pExpr) );
+            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;
+            }
+          }else
+#endif /* SQLITE_OMIT_UPSERT */
+          {
+            assert( ExprUseYTab(pExpr) );
+            pExpr->y.pTab = pTab;
+            if( pParse->bReturning ){
+              eNewExprOp = TK_REGISTER;
+              pExpr->op2 = TK_COLUMN;
+              pExpr->iTable = pNC->uNC.iBaseReg + (pTab->nCol+1)*pExpr->iTable +
+                 sqlite3TableColumnToStorage(pTab, iCol) + 1;
+            }else{
+              pExpr->iColumn = (i16)iCol;
+              eNewExprOp = TK_TRIGGER;
+#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));
+              }
+#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)
+     && ALWAYS(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( cnt==0
+     && (pNC->ncFlags & NC_UEList)!=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].fg.eEName==ENAME_NAME
+         && sqlite3_stricmp(zAs, zCol)==0
+        ){
+          Expr *pOrig;
+          assert( pExpr->pLeft==0 && pExpr->pRight==0 );
+          assert( ExprUseXList(pExpr)==0 || pExpr->x.pList==0 );
+          assert( ExprUseXSelect(pExpr)==0 || 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;
+      memset(&pExpr->y, 0, sizeof(pExpr->y));
+      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.
+  **
+  ** cnt==0 is always an error.  cnt>1 is often an error, but might
+  ** be multiple matches for a NATURAL LEFT JOIN or a LEFT JOIN USING.
+  */
+  assert( pFJMatch==0 || cnt>0 );
+  assert( !ExprHasProperty(pExpr, EP_xIsSelect|EP_IntValue) );
+  if( cnt!=1 ){
+    const char *zErr;
+    if( pFJMatch ){
+      if( pFJMatch->nExpr==cnt-1 ){
+        if( ExprHasProperty(pExpr,EP_Leaf) ){
+          ExprClearProperty(pExpr,EP_Leaf);
+        }else{
+          sqlite3ExprDelete(db, pExpr->pLeft);
+          pExpr->pLeft = 0;
+          sqlite3ExprDelete(db, pExpr->pRight);
+          pExpr->pRight = 0;
+        }
+        extendFJMatch(pParse, &pFJMatch, pMatch, pExpr->iColumn);
+        pExpr->op = TK_FUNCTION;
+        pExpr->u.zToken = "coalesce";
+        pExpr->x.pList = pFJMatch;
+        cnt = 1;
+        goto lookupname_end;
+      }else{
+        sqlite3ExprListDelete(db, pFJMatch);
+        pFJMatch = 0;
+      }
+    }
+    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);
+    }
+    sqlite3RecordErrorOffsetOfExpr(pParse->db, pExpr);
+    pParse->checkSchema = 1;
+    pTopNC->nNcErr++;
+  }
+  assert( pFJMatch==0 );
+
+  /* Remove all substructure from pExpr */
+  if( !ExprHasProperty(pExpr,(EP_TokenOnly|EP_Leaf)) ){
+    sqlite3ExprDelete(db, pExpr->pLeft);
+    pExpr->pLeft = 0;
+    sqlite3ExprDelete(db, pExpr->pRight);
+    pExpr->pRight = 0;
+    ExprSetProperty(pExpr, EP_Leaf);
+  }
+
+  /* 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);
+  }
+
+  pExpr->op = eNewExprOp;
+lookupname_end:
+  if( cnt==1 ){
+    assert( pNC!=0 );
+#ifndef SQLITE_OMIT_AUTHORIZATION
+    if( pParse->db->xAuth
+     && (pExpr->op==TK_COLUMN || pExpr->op==TK_TRIGGER)
+    ){
+      sqlite3AuthRead(pParse, pExpr, pSchema, pNC->pSrcList);
+    }
+#endif
+    /* 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 ){
+    SrcItem *pItem = &pSrc->a[iSrc];
+    Table *pTab;
+    assert( ExprUseYTab(p) );
+    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 */
+   Expr *pError         /* Associate error with this expression */
+){
+  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;
+  sqlite3RecordErrorOffsetOfExpr(pParse->db, pError);
+}
+#define sqlite3ResolveNotValid(P,N,M,X,E,R) \
+  assert( ((X)&~(NC_IsCheck|NC_PartIdx|NC_IdxExpr|NC_GenCol))==0 ); \
+  if( ((N)->ncFlags & (X))!=0 ) notValidImpl(P,N,M,E,R);
+
+/*
+** 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;
+  assert( !ExprHasProperty(p, EP_IntValue) );
+  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;
+      SrcItem *pItem;
+      assert( pSrcList && pSrcList->nSrc>=1 );
+      pItem = pSrcList->a;
+      pExpr->op = TK_COLUMN;
+      assert( ExprUseYTab(pExpr) );
+      pExpr->y.pTab = pItem->pTab;
+      pExpr->iTable = pItem->iCursor;
+      pExpr->iColumn--;
+      pExpr->affExpr = SQLITE_AFF_INTEGER;
+      break;
+    }
+
+    /* An optimization:  Attempt to convert
+    **
+    **      "expr IS NOT NULL"  -->  "TRUE"
+    **      "expr IS NULL"      -->  "FALSE"
+    **
+    ** if we can prove that "expr" is never NULL.  Call this the
+    ** "NOT NULL strength reduction optimization".
+    **
+    ** If this optimization occurs, also restore the NameContext ref-counts
+    ** to the state they where in before the "column" LHS expression was
+    ** resolved.  This prevents "column" from being counted as having been
+    ** referenced, which might prevent a SELECT from being erroneously
+    ** marked as correlated.
+    */
+    case TK_NOTNULL:
+    case TK_ISNULL: {
+      int anRef[8];
+      NameContext *p;
+      int i;
+      for(i=0, p=pNC; p && i<ArraySize(anRef); p=p->pNext, i++){ 
+        anRef[i] = p->nRef;
+      }
+      sqlite3WalkExpr(pWalker, pExpr->pLeft);
+      if( 0==sqlite3ExprCanBeNull(pExpr->pLeft) && !IN_RENAME_OBJECT ){
+        testcase( ExprHasProperty(pExpr, EP_OuterON) );
+        assert( !ExprHasProperty(pExpr, EP_IntValue) );
+        if( pExpr->op==TK_NOTNULL ){
+          pExpr->u.zToken = "true";
+          ExprSetProperty(pExpr, EP_IsTrue);
+        }else{
+          pExpr->u.zToken = "false";
+          ExprSetProperty(pExpr, EP_IsFalse);
+        }
+        pExpr->op = TK_TRUEFALSE;
+        for(i=0, p=pNC; p && i<ArraySize(anRef); p=p->pNext, i++){
+          p->nRef = anRef[i];
+        }
+        sqlite3ExprDelete(pParse->db, pExpr->pLeft);
+        pExpr->pLeft = 0;
+      }
+      return WRC_Prune;
+    }
+
+    /* 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;
+        assert( !ExprHasProperty(pExpr, EP_IntValue) );
+        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, pExpr);
+        pRight = pExpr->pRight;
+        if( pRight->op==TK_ID ){
+          zDb = 0;
+        }else{
+          assert( pRight->op==TK_DOT );
+          assert( !ExprHasProperty(pRight, EP_IntValue) );
+          zDb = pLeft->u.zToken;
+          pLeft = pRight->pLeft;
+          pRight = pRight->pRight;
+        }
+        assert( ExprUseUToken(pLeft) && ExprUseUToken(pRight) );
+        zTable = pLeft->u.zToken;
+        zColumn = pRight->u.zToken;
+        assert( ExprUseYTab(pExpr) );
+        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 */
+      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|EP_IntValue) );
+      zId = pExpr->u.zToken;
+      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 %#T() must be a "
+                "constant between 0.0 and 1.0", pExpr);
+              pNC->nNcErr++;
+            }
+          }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: %#T",
+                                      pExpr);
+              pNC->nNcErr++;
+            }
+            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, pExpr);
+        }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, 
+              "%#T() may not be used as a window function", pExpr
+          );
+          pNC->nNcErr++;
+        }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 %#T()",zType,pExpr);
+          pNC->nNcErr++;
+          is_agg = 0;
+        }
+#else
+        if( (is_agg && (pNC->ncFlags & NC_AllowAgg)==0) ){
+          sqlite3ErrorMsg(pParse,"misuse of aggregate function %#T()",pExpr);
+          pNC->nNcErr++;
+          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: %#T", pExpr);
+          pNC->nNcErr++;
+        }else if( wrong_num_args ){
+          sqlite3ErrorMsg(pParse,"wrong number of arguments to function %#T()",
+               pExpr);
+          pNC->nNcErr++;
+        }
+#ifndef SQLITE_OMIT_WINDOWFUNC
+        else if( is_agg==0 && ExprHasProperty(pExpr, EP_WinFunc) ){
+          sqlite3ErrorMsg(pParse, 
+              "FILTER may not be used with non-aggregate %#T()",
+              pExpr
+          );
+          pNC->nNcErr++;
+        }
+#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==0 || (ExprUseYWin(pExpr) && pWin==pExpr->y.pWin) );
+          if( IN_RENAME_OBJECT==0 ){
+            sqlite3WindowUpdate(pParse, pSel ? pSel->pWinDefn : 0, pWin, pDef);
+            if( pParse->db->mallocFailed ) break;
+          }
+          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;          /* For looping up thru outer contexts */
+          pExpr->op = TK_AGG_FUNCTION;
+          pExpr->op2 = 0;
+#ifndef SQLITE_OMIT_WINDOWFUNC
+          if( ExprHasProperty(pExpr, EP_WinFunc) ){
+            sqlite3WalkExpr(pWalker, pExpr->y.pWin->pFilter);
+          }
+#endif
+          pNC2 = pNC;
+          while( pNC2 
+              && sqlite3ReferencesSrcList(pParse, pExpr, pNC2->pSrcList)==0
+          ){
+            pExpr->op2++;
+            pNC2 = pNC2->pNext;
+          }
+          assert( pDef!=0 || IN_RENAME_OBJECT );
+          if( pNC2 && pDef ){
+            assert( SQLITE_FUNC_MINMAX==NC_MinMaxAgg );
+            assert( SQLITE_FUNC_ANYORDER==NC_OrderAgg );
+            testcase( (pDef->funcFlags & SQLITE_FUNC_MINMAX)!=0 );
+            testcase( (pDef->funcFlags & SQLITE_FUNC_ANYORDER)!=0 );
+            pNC2->ncFlags |= NC_HasAgg 
+              | ((pDef->funcFlags^SQLITE_FUNC_ANYORDER)
+                  & (SQLITE_FUNC_MINMAX|SQLITE_FUNC_ANYORDER));
+          }
+        }
+        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( ExprUseXSelect(pExpr) ){
+        int nRef = pNC->nRef;
+        testcase( pNC->ncFlags & NC_IsCheck );
+        testcase( pNC->ncFlags & NC_PartIdx );
+        testcase( pNC->ncFlags & NC_IdxExpr );
+        testcase( pNC->ncFlags & NC_GenCol );
+        if( pNC->ncFlags & NC_SelfRef ){
+          notValidImpl(pParse, pNC, "subqueries", pExpr, pExpr);
+        }else{
+          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, 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( ALWAYS(pRight) && (pRight->op==TK_ID || pRight->op==TK_TRUEFALSE) ){
+        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;
+        }
+      }
+      /* no break */ deliberate_fall_through
+    }
+    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 ){
+        assert( ExprUseXList(pExpr) );
+        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");
+        sqlite3RecordErrorOffsetOfExpr(pParse->db, pExpr);
+      }
+      break; 
+    }
+  }
+  assert( pParse->db->mallocFailed==0 || pParse->nErr!=0 );
+  return pParse->nErr ? 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 ){
+    const char *zCol;
+    assert( !ExprHasProperty(pE, EP_IntValue) );
+    zCol = pE->u.zToken;
+    for(i=0; i<pEList->nExpr; i++){
+      if( pEList->a[i].fg.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_NoSelect;
+  nc.nNcErr = 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(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 */
+  Expr *pError           /* Associate the error with the expression */
+){
+  sqlite3ErrorMsg(pParse, 
+    "%r %s BY term out of range - should be "
+    "between 1 and %d", i, zType, mx);
+  sqlite3RecordErrorOffsetOfExpr(pParse->db, pError);
+}
+
+/*
+** 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].fg.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->fg.done ) continue;
+      pE = sqlite3ExprSkipCollateAndLikely(pItem->pExpr);
+      if( NEVER(pE==0) ) continue;
+      if( sqlite3ExprIsInteger(pE, &iCol) ){
+        if( iCol<=0 || iCol>pEList->nExpr ){
+          resolveOutOfRangeError(pParse, "ORDER", i+1, pEList->nExpr, pE);
+          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.
+          **
+          ** If this is running as part of an ALTER TABLE operation and
+          ** the symbols resolve successfully, also resolve the symbols in the
+          ** actual expression. This allows the code in alter.c to modify
+          ** column references within the ORDER BY expression as required.  */
+          pDup = sqlite3ExprDup(db, pE, 0);
+          if( !db->mallocFailed ){
+            assert(pDup);
+            iCol = resolveOrderByTermToExprList(pParse, pSelect, pDup);
+            if( IN_RENAME_OBJECT && iCol>0 ){
+              resolveOrderByTermToExprList(pParse, pSelect, pE);
+            }
+          }
+          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->fg.done = 1;
+      }else{
+        moreToDo = 1;
+      }
+    }
+    pSelect = pSelect->pNext;
+  }
+  for(i=0; i<pOrderBy->nExpr; i++){
+    if( pOrderBy->a[i].fg.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, 0);
+        return 1;
+      }
+      resolveAlias(pParse, pEList, pItem->u.x.iOrderByCol-1, pItem->pExpr,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 */
+
+  assert( pOrderBy!=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( NEVER(pE2==0) ) continue;
+    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, pE2);
+        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 expresion 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 ? 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 );
+    assert( db->suppressErr==0 ); /* SF_Resolved not set if errors suppressed */
+    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 in the FROM clause
+    */
+    for(i=0; i<p->pSrc->nSrc; i++){
+      SrcItem *pItem = &p->pSrc->a[i];
+      if( pItem->pSelect && (pItem->pSelect->selFlags & SF_Resolved)==0 ){
+        int nRef = pOuterNC ? pOuterNC->nRef : 0;
+        const char *zSavedContext = pParse->zAuthContext;
+
+        if( pItem->zName ) pParse->zAuthContext = pItem->zName;
+        sqlite3ResolveSelectNames(pParse, pItem->pSelect, pOuterNC);
+        pParse->zAuthContext = zSavedContext;
+        if( pParse->nErr ) return WRC_Abort;
+        assert( db->mallocFailed==0 );
+
+        /* If the number of references to the outer context changed when
+        ** expressions in the sub-select were resolved, the sub-select
+        ** is correlated. It is not required to check the refcount on any
+        ** but the innermost outer context object, as lookupName() increments
+        ** the refcount on all contexts between the current one and the
+        ** context containing the column when it resolves a name. */
+        if( pOuterNC ){
+          assert( pItem->fg.isCorrelated==0 && pOuterNC->nRef>=nRef );
+          pItem->fg.isCorrelated = (pOuterNC->nRef>nRef);
+        }
+      }
+    }
+  
+    /* 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 );
+      assert( NC_OrderAgg==SF_OrderByReqd );
+      p->selFlags |= SF_Aggregate | (sNC.ncFlags&(NC_MinMaxAgg|NC_OrderAgg));
+    }else{
+      sNC.ncFlags &= ~NC_AllowAgg;
+    }
+  
+    /* 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|NC_UBaseReg))==0 );
+    sNC.uNC.pEList = p->pEList;
+    sNC.ncFlags |= NC_UEList;
+    if( p->pHaving ){
+      if( (p->selFlags & SF_Aggregate)==0 ){
+        sqlite3ErrorMsg(pParse, "HAVING clause on a non-aggregate query");
+        return WRC_Abort;
+      }
+      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++){
+      SrcItem *pItem = &p->pSrc->a[i];
+      if( pItem->fg.isTabFunc
+       && sqlite3ResolveExprListNames(&sNC, pItem->u1.pFuncArg) 
+      ){
+        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
+
+    /* 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( p->pOrderBy!=0
+     && 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;
+        }
+      }
+    }
+
+    /* 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|NC_OrderAgg);
+  pNC->ncFlags &= ~(NC_HasAgg|NC_MinMaxAgg|NC_HasWin|NC_OrderAgg);
+  w.pParse = pNC->pParse;
+  w.xExprCallback = resolveExprStep;
+  w.xSelectCallback = (pNC->ncFlags & NC_NoSelect) ? 0 : 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->nNcErr>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|NC_OrderAgg);
+  pNC->ncFlags &= ~(NC_HasAgg|NC_MinMaxAgg|NC_HasWin|NC_OrderAgg);
+  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|NC_OrderAgg) ){
+      ExprSetProperty(pExpr, pNC->ncFlags & (NC_HasAgg|NC_HasWin) );
+      savedHasAgg |= pNC->ncFlags &
+                          (NC_HasAgg|NC_MinMaxAgg|NC_HasWin|NC_OrderAgg);
+      pNC->ncFlags &= ~(NC_HasAgg|NC_MinMaxAgg|NC_HasWin|NC_OrderAgg);
+    }
+    if( 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
+** 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 );
+  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;
+}