SQLite

  testcase( p->selFlags & SF_CopyCte );
  if( p->selFlags & (SF_View|SF_CopyCte) ){
    return WRC_Prune;
  }
  if( ALWAYS(p->pEList) ){
    ExprList *pList = p->pEList;
    for(i=0; i<pList->nExpr; i++){
      if( pList->a[i].zEName && pList->a[i].eEName==ENAME_NAME ){
      if( pList->a[i].zEName && pList->a[i].fg.eEName==ENAME_NAME ){
        sqlite3RenameTokenRemap(pParse, 0, (void*)pList->a[i].zEName);
      }
    }
  }
  if( ALWAYS(p->pSrc) ){  /* Every Select as a SrcList, even if it is empty */
    SrcList *pSrc = p->pSrc;
    for(i=0; i<pSrc->nSrc; i++){

    int i;
    Walker sWalker;
    memset(&sWalker, 0, sizeof(Walker));
    sWalker.pParse = pParse;
    sWalker.xExprCallback = renameUnmapExprCb;
    sqlite3WalkExprList(&sWalker, pEList);
    for(i=0; i<pEList->nExpr; i++){
      if( ALWAYS(pEList->a[i].eEName==ENAME_NAME) ){
      if( ALWAYS(pEList->a[i].fg.eEName==ENAME_NAME) ){
        sqlite3RenameTokenRemap(pParse, 0, (void*)pEList->a[i].zEName);
      }
    }
  }
}

/*

  const ExprList *pEList, 
  const char *zOld
){
  if( pEList ){
    int i;
    for(i=0; i<pEList->nExpr; i++){
      const char *zName = pEList->a[i].zEName;
      if( ALWAYS(pEList->a[i].eEName==ENAME_NAME)
      if( ALWAYS(pEList->a[i].fg.eEName==ENAME_NAME)
       && ALWAYS(zName!=0)
       && 0==sqlite3_stricmp(zName, zOld)
      ){
        renameTokenFind(pParse, pCtx, (const void*)zName);
      }
    }
  }

      Expr *pCExpr = sqlite3ExprSkipCollate(pList->a[0].pExpr);
      sqlite3RenameTokenRemap(pParse, &pTab->iPKey, pCExpr);
    }
    pTab->iPKey = iCol;
    pTab->keyConf = (u8)onError;
    assert( autoInc==0 || autoInc==1 );
    pTab->tabFlags |= autoInc*TF_Autoincrement;
    if( pList ) pParse->iPkSortOrder = pList->a[0].sortFlags;
    if( pList ) pParse->iPkSortOrder = pList->a[0].fg.sortFlags;
    (void)sqlite3HasExplicitNulls(pParse, pList);
  }else if( autoInc ){
#ifndef SQLITE_OMIT_AUTOINCREMENT
    sqlite3ErrorMsg(pParse, "AUTOINCREMENT is only allowed on an "
       "INTEGER PRIMARY KEY");
#endif
  }else{

    if( pList==0 ){
      pTab->tabFlags &= ~TF_WithoutRowid;
      return;
    }
    if( IN_RENAME_OBJECT ){
      sqlite3RenameTokenRemap(pParse, pList->a[0].pExpr, &pTab->iPKey);
    }
    pList->a[0].sortFlags = pParse->iPkSortOrder;
    pList->a[0].fg.sortFlags = pParse->iPkSortOrder;
    assert( pParse->pNewTable==pTab );
    pTab->iPKey = -1;
    sqlite3CreateIndex(pParse, 0, 0, 0, pList, pTab->keyConf, 0, 0, 0, 0,
                       SQLITE_IDXTYPE_PRIMARYKEY);
    if( pParse->nErr ){
      pTab->tabFlags &= ~TF_WithoutRowid;
      return;

** an explicit "NULLS FIRST" or "NULLS LAST" clause, leave an error in
** pParse and return non-zero. Otherwise, return zero.
*/
int sqlite3HasExplicitNulls(Parse *pParse, ExprList *pList){
  if( pList ){
    int i;
    for(i=0; i<pList->nExpr; i++){
      if( pList->a[i].bNulls ){
        u8 sf = pList->a[i].sortFlags;
      if( pList->a[i].fg.bNulls ){
        u8 sf = pList->a[i].fg.sortFlags;
        sqlite3ErrorMsg(pParse, "unsupported use of NULLS %s", 
            (sf==0 || sf==3) ? "FIRST" : "LAST"
        );
        return 1;
      }
    }
  }

      zColl = sqlite3ColumnColl(&pTab->aCol[j]);
    }
    if( !zColl ) zColl = sqlite3StrBINARY;
    if( !db->init.busy && !sqlite3LocateCollSeq(pParse, zColl) ){
      goto exit_create_index;
    }
    pIndex->azColl[i] = zColl;
    requestedSortOrder = pListItem->sortFlags & sortOrderMask;
    requestedSortOrder = pListItem->fg.sortFlags & sortOrderMask;
    pIndex->aSortOrder[i] = (u8)requestedSortOrder;
  }

  /* Append the table key to the end of the index.  For WITHOUT ROWID
  ** tables (when pPk!=0) this will be the declared PRIMARY KEY.  For
  ** normal tables (when pPk==0) this will be the rowid.
  */

          pPriorSelectColNew = sqlite3ExprDup(db, pPriorSelectColOld, flags);
          pNewExpr->pRight = pPriorSelectColNew;
        }
        pNewExpr->pLeft = pPriorSelectColNew;
      }
    }
    pItem->zEName = sqlite3DbStrDup(db, pOldItem->zEName);
    pItem->sortFlags = pOldItem->sortFlags;
    pItem->eEName = pOldItem->eEName;
    pItem->done = 0;
    pItem->fg = pOldItem->fg;
    pItem->fg.done = 0;
    pItem->bNulls = pOldItem->bNulls;
    pItem->bUsed = pOldItem->bUsed;
    pItem->bSorterRef = pOldItem->bSorterRef;
    pItem->u = pOldItem->u;
  }
  return pNew;
}

/*
** If cursors, triggers, views and subqueries are all omitted from

  );
  assert( eNulls==SQLITE_SO_UNDEFINED 
       || eNulls==SQLITE_SO_ASC 
       || eNulls==SQLITE_SO_DESC 
  );

  pItem = &p->a[p->nExpr-1];
  assert( pItem->bNulls==0 );
  assert( pItem->fg.bNulls==0 );
  if( iSortOrder==SQLITE_SO_UNDEFINED ){
    iSortOrder = SQLITE_SO_ASC;
  }
  pItem->sortFlags = (u8)iSortOrder;
  pItem->fg.sortFlags = (u8)iSortOrder;

  if( eNulls!=SQLITE_SO_UNDEFINED ){
    pItem->bNulls = 1;
    pItem->fg.bNulls = 1;
    if( iSortOrder!=eNulls ){
      pItem->sortFlags |= KEYINFO_ORDER_BIGNULL;
      pItem->fg.sortFlags |= KEYINFO_ORDER_BIGNULL;
    }
  }
}

/*
** Set the ExprList.a[].zEName element of the most recently added item
** on the expression list.

  assert( pList!=0 || pParse->db->mallocFailed!=0 );
  assert( pParse->eParseMode!=PARSE_MODE_UNMAP || dequote==0 );
  if( pList ){
    struct ExprList_item *pItem;
    assert( pList->nExpr>0 );
    pItem = &pList->a[pList->nExpr-1];
    assert( pItem->zEName==0 );
    assert( pItem->eEName==ENAME_NAME );
    assert( pItem->fg.eEName==ENAME_NAME );
    pItem->zEName = sqlite3DbStrNDup(pParse->db, pName->z, pName->n);
    if( dequote ){
      /* If dequote==0, then pName->z does not point to part of a DDL
      ** statement handled by the parser. And so no token need be added
      ** to the token-map.  */
      sqlite3Dequote(pItem->zEName);
      if( IN_RENAME_OBJECT ){

  sqlite3 *db = pParse->db;
  assert( pList!=0 || db->mallocFailed!=0 );
  if( pList ){
    struct ExprList_item *pItem = &pList->a[pList->nExpr-1];
    assert( pList->nExpr>0 );
    if( pItem->zEName==0 ){
      pItem->zEName = sqlite3DbSpanDup(db, zStart, zEnd);
      pItem->eEName = ENAME_SPAN;
      pItem->fg.eEName = ENAME_SPAN;
    }
  }
}

/*
** If the expression list pEList contains more than iLimit elements,
** leave an error message in pParse.

  ExprList *p;
  assert( ConstFactorOk(pParse) );
  p = pParse->pConstExpr;
  if( regDest<0 && p ){
    struct ExprList_item *pItem;
    int i;
    for(pItem=p->a, i=p->nExpr; i>0; pItem++, i--){
      if( pItem->fg.reusable
      if( pItem->reusable && sqlite3ExprCompare(0,pItem->pExpr,pExpr,-1)==0 ){
       && sqlite3ExprCompare(0,pItem->pExpr,pExpr,-1)==0
      ){
        return pItem->u.iConstExprReg;
      }
    }
  }
  pExpr = sqlite3ExprDup(pParse->db, pExpr, 0);
  if( pExpr!=0 && ExprHasProperty(pExpr, EP_HasFunc) ){
    Vdbe *v = pParse->pVdbe;

    pParse->okConstFactor = 1;
    sqlite3ExprDelete(pParse->db, pExpr);
    sqlite3VdbeJumpHere(v, addr);
  }else{
    p = sqlite3ExprListAppend(pParse, p, pExpr);
    if( p ){
       struct ExprList_item *pItem = &p->a[p->nExpr-1];
       pItem->reusable = regDest<0;
       pItem->fg.reusable = regDest<0;
       if( regDest<0 ) regDest = ++pParse->nMem;
       pItem->u.iConstExprReg = regDest;
    }
    pParse->pConstExpr = p;
  }
  return regDest;
}

  assert( target>0 );
  assert( pParse->pVdbe!=0 );  /* Never gets this far otherwise */
  n = pList->nExpr;
  if( !ConstFactorOk(pParse) ) flags &= ~SQLITE_ECEL_FACTOR;
  for(pItem=pList->a, i=0; i<n; i++, pItem++){
    Expr *pExpr = pItem->pExpr;
#ifdef SQLITE_ENABLE_SORTER_REFERENCES
    if( pItem->bSorterRef ){
    if( pItem->fg.bSorterRef ){
      i--;
      n--;
    }else
#endif
    if( (flags & SQLITE_ECEL_REF)!=0 && (j = pItem->u.x.iOrderByCol)>0 ){
      if( flags & SQLITE_ECEL_OMITREF ){
        i--;

  if( pA==0 && pB==0 ) return 0;
  if( pA==0 || pB==0 ) return 1;
  if( pA->nExpr!=pB->nExpr ) return 1;
  for(i=0; i<pA->nExpr; i++){
    int res;
    Expr *pExprA = pA->a[i].pExpr;
    Expr *pExprB = pB->a[i].pExpr;
    if( pA->a[i].sortFlags!=pB->a[i].sortFlags ) return 1;
    if( pA->a[i].fg.sortFlags!=pB->a[i].fg.sortFlags ) return 1;
    if( (res = sqlite3ExprCompare(0, pExprA, pExprB, iTab)) ) return res;
  }
  return 0;
}

/*
** Like sqlite3ExprCompare() except COLLATE operators at the top-level

  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;
  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++){}

                extendFJMatch(pParse, &pFJMatch, pMatch, pExpr->iColumn);
              }
            }
            cnt++;
            cntTab = 2;
            pMatch = pItem;
            pExpr->iColumn = j;
            pEList->a[j].bUsed = 1;
            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 ){

     && (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].eEName==ENAME_NAME
        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;

  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].eEName==ENAME_NAME
      if( pEList->a[i].fg.eEName==ENAME_NAME
       && sqlite3_stricmp(pEList->a[i].zEName, zCol)==0
      ){
        return i+1;
      }
    }
  }
  return 0;

  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;
    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->done ) continue;
      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;
        }

            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;
        pItem->fg.done = 1;
      }else{
        moreToDo = 1;
      }
    }
    pSelect = pSelect->pNext;
  }
  for(i=0; i<pOrderBy->nExpr; i++){
    if( pOrderBy->a[i].done==0 ){
    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;
}

  assert( pItem->fg.isNestedFrom == IsNestedFrom(pItem->pSelect) );
  if( pItem->fg.isNestedFrom ){
    ExprList *pResults;
    assert( pItem->pSelect!=0 );
    pResults = pItem->pSelect->pEList;
    assert( pResults!=0 );
    assert( iCol>=0 && iCol<pResults->nExpr );
    pResults->a[iCol].bUsed = 1;
    pResults->a[iCol].fg.bUsed = 1;
  }
}

/*
** Search the tables iStart..iEnd (inclusive) in pSrc, looking for a
** table that has a column named zCol.  The search is left-to-right.
** The first match found is returned.

** If the optimization is used for expression "bigblob", then instead of
** storing values read from that column in the sorter records, the PK of
** the row from table t1 is stored instead. Then, as records are extracted from
** the sorter to return to the user, the required value of bigblob is
** retrieved directly from table t1. If the values are very large, this 
** can be more efficient than storing them directly in the sorter records.
**
** The ExprList_item.bSorterRef flag is set for each expression in pEList 
** The ExprList_item.fg.bSorterRef flag is set for each expression in pEList 
** for which the sorter-reference optimization should be enabled. 
** Additionally, the pSort->aDefer[] array is populated with entries
** for all cursors required to evaluate all selected expressions. Finally.
** output variable (*ppExtra) is set to an expression list containing
** expressions for all extra PK values that should be stored in the
** sorter records.
*/

            }
            pSort->aDefer[nDefer].pTab = pExpr->y.pTab;
            pSort->aDefer[nDefer].iCsr = pExpr->iTable;
            pSort->aDefer[nDefer].nKey = nKey;
            nDefer++;
          }
        }
        pItem->bSorterRef = 1;
        pItem->fg.bSorterRef = 1;
      }
    }
  }
  pSort->nDefer = (u8)nDefer;
  *ppExtra = pExtra;
}
#endif

      /* Adjust nResultCol to account for columns that are omitted
      ** from the sorter by the optimizations in this branch */
      pEList = p->pEList;
      for(i=0; i<pEList->nExpr; i++){
        if( pEList->a[i].u.x.iOrderByCol>0
#ifdef SQLITE_ENABLE_SORTER_REFERENCES
         || pEList->a[i].bSorterRef
         || pEList->a[i].fg.bSorterRef
#endif
        ){
          nResultCol--;
          regOrig = 0;
        }
      }

  nExpr = pList->nExpr;
  pInfo = sqlite3KeyInfoAlloc(db, nExpr-iStart, nExtra+1);
  if( pInfo ){
    assert( sqlite3KeyInfoIsWriteable(pInfo) );
    for(i=iStart, pItem=pList->a+iStart; i<nExpr; i++, pItem++){
      pInfo->aColl[i-iStart] = sqlite3ExprNNCollSeq(pParse, pItem->pExpr);
      pInfo->aSortFlags[i-iStart] = pItem->sortFlags;
      pInfo->aSortFlags[i-iStart] = pItem->fg.sortFlags;
    }
  }
  return pInfo;
}

/*
** Name of the connection operator, used for error messages.

    addr = 1 + sqlite3VdbeAddOp2(v, OP_Sort, iTab, addrBreak); VdbeCoverage(v);
    codeOffset(v, p->iOffset, addrContinue);
    iSortTab = iTab;
    bSeq = 1;
  }
  for(i=0, iCol=nKey+bSeq-1; i<nColumn; i++){
#ifdef SQLITE_ENABLE_SORTER_REFERENCES
    if( aOutEx[i].bSorterRef ) continue;
    if( aOutEx[i].fg.bSorterRef ) continue;
#endif
    if( aOutEx[i].u.x.iOrderByCol==0 ) iCol++;
  }
#ifdef SQLITE_ENABLE_SORTER_REFERENCES
  if( pSort->nDefer ){
    int iKey = iCol+1;
    int regKey = sqlite3GetTempRange(pParse, nRefKey);

      }
    }
    sqlite3ReleaseTempRange(pParse, regKey, nRefKey);
  }
#endif
  for(i=nColumn-1; i>=0; i--){
#ifdef SQLITE_ENABLE_SORTER_REFERENCES
    if( aOutEx[i].bSorterRef ){
    if( aOutEx[i].fg.bSorterRef ){
      sqlite3ExprCode(pParse, aOutEx[i].pExpr, regRow+i);
    }else
#endif
    {
      int iRead;
      if( aOutEx[i].u.x.iOrderByCol ){
        iRead = aOutEx[i].u.x.iOrderByCol-1;

  for(i=0; i<pEList->nExpr; i++){
    Expr *p = pEList->a[i].pExpr;

    assert( p!=0 );
    assert( p->op!=TK_AGG_COLUMN );  /* Agg processing has not run yet */
    assert( p->op!=TK_COLUMN
        || (ExprUseYTab(p) && p->y.pTab!=0) ); /* Covering idx not yet coded */
    if( pEList->a[i].zEName && pEList->a[i].eEName==ENAME_NAME ){
    if( pEList->a[i].zEName && pEList->a[i].fg.eEName==ENAME_NAME ){
      /* An AS clause always takes first priority */
      char *zName = pEList->a[i].zEName;
      sqlite3VdbeSetColName(v, i, COLNAME_NAME, zName, SQLITE_TRANSIENT);
    }else if( srcName && p->op==TK_COLUMN ){
      char *zCol;
      int iCol = p->iColumn;
      pTab = p->y.pTab;

  }
  assert( nCol==(i16)nCol );
  *pnCol = nCol;
  *paCol = aCol;

  for(i=0, pCol=aCol; i<nCol && !db->mallocFailed; i++, pCol++){
    struct ExprList_item *pX = &pEList->a[i];
    struct ExprList_item *pCollide;
    /* Get an appropriate name for the column
    */
    if( (zName = pX->zEName)!=0 && pX->eEName==ENAME_NAME ){
    if( (zName = pX->zEName)!=0 && pX->fg.eEName==ENAME_NAME ){
      /* If the column contains an "AS <name>" phrase, use <name> as the name */
    }else{
      Expr *pColExpr = sqlite3ExprSkipCollateAndLikely(pX->pExpr);
      while( ALWAYS(pColExpr!=0) && pColExpr->op==TK_DOT ){
        pColExpr = pColExpr->pRight;
        assert( pColExpr!=0 );
      }

      zName = sqlite3MPrintf(db,"column%d",i+1);
    }

    /* Make sure the column name is unique.  If the name is not unique,
    ** append an integer to the name so that it becomes unique.
    */
    cnt = 0;
    while( zName && sqlite3HashFind(&ht, zName)!=0 ){
    while( zName && (pCollide = sqlite3HashFind(&ht, zName))!=0 ){
      if( pCollide->fg.bUsingTerm ){
        pCol->colFlags |= COLFLAG_NOEXPAND;
      }
      nName = sqlite3Strlen30(zName);
      if( nName>0 ){
        for(j=nName-1; j>0 && sqlite3Isdigit(zName[j]); j--){}
        if( zName[j]==':' ) nName = j;
      }
      zName = sqlite3MPrintf(db, "%.*z:%u", nName, zName, ++cnt);
      if( cnt>3 ) sqlite3_randomness(sizeof(cnt), &cnt);
    }
    pCol->zCnName = zName;
    pCol->hName = sqlite3StrIHash(zName);
    if( pX->fg.bNoExpand ){
      pCol->colFlags |= COLFLAG_NOEXPAND;
    }
    sqlite3ColumnPropertiesFromName(0, pCol);
    if( zName && sqlite3HashInsert(&ht, zName, pCol)==pCol ){
    if( zName && sqlite3HashInsert(&ht, zName, pX)==pX ){
      sqlite3OomFault(db);
    }
  }
  sqlite3HashClear(&ht);
  if( db->mallocFailed ){
    for(j=0; j<i; j++){
      sqlite3DbFree(db, aCol[j].zCnName);

        pColl = multiSelectCollSeq(pParse, p, pItem->u.x.iOrderByCol-1);
        if( pColl==0 ) pColl = db->pDfltColl;
        pOrderBy->a[i].pExpr =
          sqlite3ExprAddCollateString(pParse, pTerm, pColl->zName);
      }
      assert( sqlite3KeyInfoIsWriteable(pRet) );
      pRet->aColl[i] = pColl;
      pRet->aSortFlags[i] = pOrderBy->a[i].sortFlags;
      pRet->aSortFlags[i] = pOrderBy->a[i].fg.sortFlags;
    }
  }

  return pRet;
}

#ifndef SQLITE_OMIT_CTE

    eRet = WHERE_ORDERBY_MAX;
    sortFlags = KEYINFO_ORDER_DESC;
  }else{
    return eRet;
  }
  *ppMinMax = pOrderBy = sqlite3ExprListDup(db, pEList, 0);
  assert( pOrderBy!=0 || db->mallocFailed );
  if( pOrderBy ) pOrderBy->a[0].sortFlags = sortFlags;
  if( pOrderBy ) pOrderBy->a[0].fg.sortFlags = sortFlags;
  return eRet;
}

/*
** The select statement passed as the first argument is an aggregate query.
** The second argument is the associated aggregate-info object. This 
** function tests if the SELECT is of the form:

       && (pE->op!=TK_DOT || pRight->op!=TK_ASTERISK)
      ){
        /* This particular expression does not need to be expanded.
        */
        pNew = sqlite3ExprListAppend(pParse, pNew, a[k].pExpr);
        if( pNew ){
          pNew->a[pNew->nExpr-1].zEName = a[k].zEName;
          pNew->a[pNew->nExpr-1].eEName = a[k].eEName;
          pNew->a[pNew->nExpr-1].fg.eEName = a[k].fg.eEName;
          a[k].zEName = 0;
        }
        a[k].pExpr = 0;
      }else{
        /* This expression is a "*" or a "TABLE.*" and needs to be
        ** expanded. */
        int tableSeen = 0;      /* Set to 1 when TABLE matches */
        char *zTName = 0;       /* text of name of TABLE */
        if( pE->op==TK_DOT ){
          assert( pE->pLeft!=0 );
          assert( !ExprHasProperty(pE->pLeft, EP_IntValue) );
          zTName = pE->pLeft->u.zToken;
        }
        for(i=0, pFrom=pTabList->a; i<pTabList->nSrc; i++, pFrom++){
          Table *pTab = pFrom->pTab;   /* Table for this data source */
          ExprList *pNestedFrom;       /* Result-set of a nested FROM clause */
          char *zTabName;              /* AS name for this data source */
          const char *zSchemaName = 0; /* Schema name for this data source */
          int iDb;                     /* Schema index for this data src */
          IdList *pUsing;              /* USING clause for pFrom[1] */

          if( (zTabName = pFrom->zAlias)==0 ){
            zTabName = pTab->zName;
          }
          if( db->mallocFailed ) break;
          assert( pFrom->fg.isNestedFrom == IsNestedFrom(pFrom->pSelect) );
          if( pFrom->fg.isNestedFrom ){
            assert( pFrom->pSelect!=0 );
            pNestedFrom = pFrom->pSelect->pEList;
            assert( pNestedFrom!=0 );
            assert( pNestedFrom->nExpr==pTab->nCol );
          }else{
            if( zTName && sqlite3StrICmp(zTName, zTabName)!=0 ){
              continue;
            }
            pNestedFrom = 0;
            iDb = sqlite3SchemaToIndex(db, pTab->pSchema);
            zSchemaName = iDb>=0 ? db->aDb[iDb].zDbSName : "*";
          }
          if( i+1<pTabList->nSrc
           && pFrom[1].fg.isUsing
           && (selFlags & SF_NestedFrom)!=0
          ){
            int ii;
            pUsing = pFrom[1].u3.pUsing;
            for(ii=0; ii<pUsing->nId; ii++){
              const char *zUName = pUsing->a[ii].zName;
              pRight = sqlite3Expr(db, TK_ID, zUName);
              pNew = sqlite3ExprListAppend(pParse, pNew, pRight);
              if( pNew ){
                struct ExprList_item *pX = &pNew->a[pNew->nExpr-1];
                assert( pX->zEName==0 );
                pX->zEName = sqlite3MPrintf(db,"..%s", zUName);
                pX->fg.eEName = ENAME_TAB;
                pX->fg.bUsingTerm = 1;
              }
            }
          }else{
            pUsing = 0;
          }
          for(j=0; j<pTab->nCol; j++){
            char *zName = pTab->aCol[j].zCnName;
            struct ExprList_item *pX; /* Newly added ExprList term */

            assert( zName );
            if( zTName
             && pNestedFrom
             && sqlite3MatchEName(&pNestedFrom->a[j], 0, zTName, 0)==0
            ){
              continue;
            }

            /* If a column is marked as 'hidden', omit it from the expanded
            ** result-set list unless the SELECT has the SF_IncludeHidden
            ** bit set.
            */
            if( (p->selFlags & SF_IncludeHidden)==0
             && IsHiddenColumn(&pTab->aCol[j]) 
            ){
              continue;
            if( pTab->aCol[j].colFlags & (COLFLAG_HIDDEN|COLFLAG_NOEXPAND) ){
              if( IsHiddenColumn(&pTab->aCol[j])
               && (selFlags & (SF_IncludeHidden|SF_NestedFrom))==0
              ){
                continue;
              }
              if( (pTab->aCol[j].colFlags & COLFLAG_NOEXPAND)!=0
               && zTName==0
               && (selFlags & (SF_NestedFrom))==0
              ){
                continue;
              }
            }
            tableSeen = 1;

            if( i>0 && zTName==0 ){
            if( i>0 && zTName==0 && (selFlags & SF_NestedFrom)==0 ){
              if( pFrom->fg.isUsing
               && sqlite3IdListIndex(pFrom->u3.pUsing, zName)>=0
              ){
                /* In a join with a USING clause, omit columns in the
                ** using clause from the table on the right. */
                continue;
              }
            }
            pRight = sqlite3Expr(db, TK_ID, zName);
            if( (pTabList->nSrc>1
                 && (  (pFrom->fg.jointype & JT_LTORJ)==0
                     || (selFlags & SF_NestedFrom)!=0
                     || !inAnyUsingClause(zName,pFrom,pTabList->nSrc-i-1)
                    )
                )
             || IN_RENAME_OBJECT
            ){
              Expr *pLeft;
              pLeft = sqlite3Expr(db, TK_ID, zTabName);

                pX->zEName = sqlite3DbStrDup(db, pNestedFrom->a[j].zEName);
                testcase( pX->zEName==0 );
              }else{
                pX->zEName = sqlite3MPrintf(db, "%s.%s.%s",
                                           zSchemaName, zTabName, zName);
                testcase( pX->zEName==0 );
              }
              pX->eEName = ENAME_TAB;
              pX->fg.eEName = ENAME_TAB;
              if( (pFrom->fg.isUsing
                   && sqlite3IdListIndex(pFrom->u3.pUsing, zName)>=0)
               || (pUsing && sqlite3IdListIndex(pUsing, zName)>=0)
               || (pTab->aCol[j].colFlags & COLFLAG_NOEXPAND)!=0
              ){
                pX->fg.bNoExpand = 1;
              }
            }else if( longNames ){
              pX->zEName = sqlite3MPrintf(db, "%s.%s", zTabName, zName);
              pX->eEName = ENAME_NAME;
              pX->fg.eEName = ENAME_NAME;
            }else{
              pX->zEName = sqlite3DbStrDup(db, zName);
              pX->eEName = ENAME_NAME;
              pX->fg.eEName = ENAME_NAME;
            }
          }
        }
        if( !tableSeen ){
          if( zTName ){
            sqlite3ErrorMsg(pParse, "no such table: %s", zTName);
          }else{

  /* If the output is destined for a temporary table, open that table.
  */
  if( pDest->eDest==SRT_EphemTab ){
    sqlite3VdbeAddOp2(v, OP_OpenEphemeral, pDest->iSDParm, pEList->nExpr);
    if( p->selFlags & SF_NestedFrom ){
      /* Delete or NULL-out result columns that will never be used */
      int ii;
      for(ii=pEList->nExpr-1; ii>0 && pEList->a[ii].bUsed==0; ii--){
      for(ii=pEList->nExpr-1; ii>0 && pEList->a[ii].fg.bUsed==0; ii--){
        sqlite3ExprDelete(db, pEList->a[ii].pExpr);
        sqlite3DbFree(db, pEList->a[ii].zEName);
        pEList->nExpr--;
      }
      for(ii=0; ii<pEList->nExpr; ii++){
        if( pEList->a[ii].bUsed==0 ) pEList->a[ii].pExpr->op = TK_NULL;
        if( pEList->a[ii].fg.bUsed==0 ) pEList->a[ii].pExpr->op = TK_NULL;
      }
    }
  }

  /* Set the limiter.
  */
  iEnd = sqlite3VdbeMakeLabel(pParse);

        int ii;
        /* The GROUP BY processing doesn't care whether rows are delivered in
        ** ASC or DESC order - only that each group is returned contiguously.
        ** So set the ASC/DESC flags in the GROUP BY to match those in the 
        ** ORDER BY to maximize the chances of rows being delivered in an 
        ** order that makes the ORDER BY redundant.  */
        for(ii=0; ii<pGroupBy->nExpr; ii++){
          u8 sortFlags;
          u8 sortFlags = sSort.pOrderBy->a[ii].sortFlags & KEYINFO_ORDER_DESC;
          pGroupBy->a[ii].sortFlags = sortFlags;
          sortFlags = sSort.pOrderBy->a[ii].fg.sortFlags & KEYINFO_ORDER_DESC;
          pGroupBy->a[ii].fg.sortFlags = sortFlags;
        }
        if( sqlite3ExprListCompare(pGroupBy, sSort.pOrderBy, -1)==0 ){
          orderByGrp = 1;
        }
      }
    }else{
      assert( 0==sqlite3LogEst(1) );

#define COLFLAG_UNIQUE    0x0008   /* Column def contains "UNIQUE" or "PK" */
#define COLFLAG_SORTERREF 0x0010   /* Use sorter-refs with this column */
#define COLFLAG_VIRTUAL   0x0020   /* GENERATED ALWAYS AS ... VIRTUAL */
#define COLFLAG_STORED    0x0040   /* GENERATED ALWAYS AS ... STORED */
#define COLFLAG_NOTAVAIL  0x0080   /* STORED column not yet calculated */
#define COLFLAG_BUSY      0x0100   /* Blocks recursion on GENERATED columns */
#define COLFLAG_HASCOLL   0x0200   /* Has collating sequence name in zCnName */
#define COLFLAG_NOEXPAND  0x0400   /* Omit this column when expanding "*" */
#define COLFLAG_GENERATED 0x0060   /* Combo: _STORED, _VIRTUAL */
#define COLFLAG_NOINSERT  0x0062   /* Combo: _HIDDEN, _STORED, _VIRTUAL */

/*
** A "Collating Sequence" is defined by an instance of the following
** structure. Conceptually, a collating sequence consists of a name and
** a comparison routine that defines the order of that sequence.

*/
struct ExprList {
  int nExpr;             /* Number of expressions on the list */
  int nAlloc;            /* Number of a[] slots allocated */
  struct ExprList_item { /* For each expression in the list */
    Expr *pExpr;            /* The parse tree for this expression */
    char *zEName;           /* Token associated with this expression */
    struct {
    u8 sortFlags;           /* Mask of KEYINFO_ORDER_* flags */
    unsigned eEName :2;     /* Meaning of zEName */
    unsigned done :1;       /* A flag to indicate when processing is finished */
    unsigned reusable :1;   /* Constant expression is reusable */
    unsigned bSorterRef :1; /* Defer evaluation until after sorting */
    unsigned bNulls: 1;     /* True if explicit "NULLS FIRST/LAST" */
    unsigned bUsed: 1;      /* This column used in a SF_NestedFrom subquery */
      u8 sortFlags;           /* Mask of KEYINFO_ORDER_* flags */
      unsigned eEName :2;     /* Meaning of zEName */
      unsigned done :1;       /* Indicates when processing is finished */
      unsigned reusable :1;   /* Constant expression is reusable */
      unsigned bSorterRef :1; /* Defer evaluation until after sorting */
      unsigned bNulls :1;     /* True if explicit "NULLS FIRST/LAST" */
      unsigned bUsed :1;      /* This column used in a SF_NestedFrom subquery */
      unsigned bUsingTerm:1;  /* Term from the USING clause of a NestedFrom */
      unsigned bNoExpand: 1;  /* Term is an auxiliary in NestedFrom and should
                              ** not be expanded by "*" in parent queries */
    } fg;
    union {
      struct {             /* Used by any ExprList other than Parse.pConsExpr */
        u16 iOrderByCol;      /* For ORDER BY, column number in result set */
        u16 iAlias;           /* Index into Parse.aAlias[] for zName */
      } x;
      int iConstExprReg;   /* Register in which Expr value is cached. Used only
                           ** by Parse.pConstExpr */

      char *zName = pList->a[i].zEName;
      int moreToFollow = i<pList->nExpr - 1;
      if( j || zName ){
        sqlite3TreeViewPush(&pView, moreToFollow);
        moreToFollow = 0;
        sqlite3TreeViewLine(pView, 0);
        if( zName ){
          switch( pList->a[i].eEName ){
          switch( pList->a[i].fg.eEName ){
            default:
              fprintf(stdout, "AS %s ", zName);
              break;
            case ENAME_TAB:
              fprintf(stdout, "TABLE-ALIAS-NAME(\"%s\") ", zName);
              if( pList->a[i].bUsed==0 ) fprintf(stdout, "(unused) ");
              if( pList->a[i].fg.bUsed ) fprintf(stdout, "(used) ");
              if( pList->a[i].fg.bUsingTerm ) fprintf(stdout, "(USING-term) ");
              if( pList->a[i].fg.bNoExpand ) fprintf(stdout, "(NoExpand) ");
              break;
            case ENAME_SPAN:
              fprintf(stdout, "SPAN(\"%s\") ", zName);
              break;
          }
        }
        if( j ){

        Expr *pNewExpr;
        if( IsHiddenColumn(pTab->aCol+jj) ) continue;
        pNewExpr = sqlite3Expr(db, TK_ID, pTab->aCol[jj].zCnName);
        pNew = sqlite3ExprListAppend(pParse, pNew, pNewExpr);
        if( !db->mallocFailed ){
          struct ExprList_item *pItem = &pNew->a[pNew->nExpr-1];
          pItem->zEName = sqlite3DbStrDup(db, pTab->aCol[jj].zCnName);
          pItem->eEName = ENAME_NAME;
          pItem->fg.eEName = ENAME_NAME;
        }
      }
    }else{
      Expr *pNewExpr = sqlite3ExprDup(db, pOldExpr, 0);
      pNew = sqlite3ExprListAppend(pParse, pNew, pNewExpr);
      if( !db->mallocFailed && ALWAYS(pList->a[i].zEName!=0) ){
        struct ExprList_item *pItem = &pNew->a[pNew->nExpr-1];
        pItem->zEName = sqlite3DbStrDup(db, pList->a[i].zEName);
        pItem->eEName = pList->a[i].eEName;
        pItem->fg.eEName = pList->a[i].fg.eEName;
      }
    }
  }
  return pNew;
}

/*

      /* Skip over constant terms in the ORDER BY clause */
      if( sqlite3ExprIsConstant(pExpr) ){
        continue;
      }

      /* Virtual tables are unable to deal with NULLS FIRST */
      if( pOrderBy->a[i].sortFlags & KEYINFO_ORDER_BIGNULL ) break;
      if( pOrderBy->a[i].fg.sortFlags & KEYINFO_ORDER_BIGNULL ) break;

      /* First case - a direct column references without a COLLATE operator */
      if( pExpr->op==TK_COLUMN && pExpr->iTable==pSrc->iCursor ){
        assert( pExpr->iColumn>=XN_ROWID && pExpr->iColumn<pTab->nCol );
        continue;
      }

  for(i=j=0; i<nOrderBy; i++){
    Expr *pExpr = pOrderBy->a[i].pExpr;
    if( sqlite3ExprIsConstant(pExpr) ) continue;
    assert( pExpr->op==TK_COLUMN
         || (pExpr->op==TK_COLLATE && pExpr->pLeft->op==TK_COLUMN
              && pExpr->iColumn==pExpr->pLeft->iColumn) );
    pIdxOrderBy[j].iColumn = pExpr->iColumn;
    pIdxOrderBy[j].desc = pOrderBy->a[i].sortFlags & KEYINFO_ORDER_DESC;
    pIdxOrderBy[j].desc = pOrderBy->a[i].fg.sortFlags & KEYINFO_ORDER_DESC;
    j++;
  }
  pIdxInfo->nOrderBy = j;

  *pmNoOmit = mNoOmit;
  return pIdxInfo;
}

          isMatch = 1;
          break;
        }
        if( isMatch && (wctrlFlags & WHERE_GROUPBY)==0 ){
          /* Make sure the sort order is compatible in an ORDER BY clause.
          ** Sort order is irrelevant for a GROUP BY clause. */
          if( revSet ){
            if( (rev ^ revIdx)!=(pOrderBy->a[i].sortFlags&KEYINFO_ORDER_DESC) ){
            if( (rev ^ revIdx) 
                           != (pOrderBy->a[i].fg.sortFlags&KEYINFO_ORDER_DESC)
            ){
              isMatch = 0;
            }
          }else{
            rev = revIdx ^ (pOrderBy->a[i].sortFlags & KEYINFO_ORDER_DESC);
            rev = revIdx ^ (pOrderBy->a[i].fg.sortFlags & KEYINFO_ORDER_DESC);
            if( rev ) *pRevMask |= MASKBIT(iLoop);
            revSet = 1;
          }
        }
        if( isMatch && (pOrderBy->a[i].sortFlags & KEYINFO_ORDER_BIGNULL) ){
        if( isMatch && (pOrderBy->a[i].fg.sortFlags & KEYINFO_ORDER_BIGNULL) ){
          if( j==pLoop->u.btree.nEq ){
            pLoop->wsFlags |= WHERE_BIGNULL_SORT;
          }else{
            isMatch = 0;
          }
        }
        if( isMatch ){

    /* Check condition (5). Return early if it is not met. */
    if( pOrderBy ){
      for(ii=0; ii<pOrderBy->nExpr; ii++){
        Expr *pExpr = pOrderBy->a[ii].pExpr;
        if( pExpr->op!=TK_COLUMN ) return;
        if( pExpr->iTable!=iCsr ) return;
        if( pOrderBy->a[ii].sortFlags & KEYINFO_ORDER_BIGNULL ) return;
        if( pOrderBy->a[ii].fg.sortFlags & KEYINFO_ORDER_BIGNULL ) return;
      }
    }

    /* All conditions are met. Add the terms to the where-clause object. */
    assert( p->pLimit->op==TK_LIMIT );
    whereAddLimitExpr(pWC, p->iLimit, p->pLimit->pLeft,
                      iCsr, SQLITE_INDEX_CONSTRAINT_LIMIT);

        if( sqlite3ExprIsInteger(pSub, &iDummy) ){
          pSub->op = TK_NULL;
          pSub->flags &= ~(EP_IntValue|EP_IsTrue|EP_IsFalse);
          pSub->u.zToken = 0;
        }
      }
      pList = sqlite3ExprListAppend(pParse, pList, pDup);
      if( pList ) pList->a[nInit+i].sortFlags = pAppend->a[i].sortFlags;
      if( pList ) pList->a[nInit+i].fg.sortFlags = pAppend->a[i].fg.sortFlags;
    }
  }
  return pList;
}

/*
** When rewriting a query, if the new subquery in the FROM clause

  /* Read the peer-value from each cursor into a register */
  windowReadPeerValues(p, csr1, reg1);
  windowReadPeerValues(p, csr2, reg2);

  assert( op==OP_Ge || op==OP_Gt || op==OP_Le );
  assert( pOrderBy && pOrderBy->nExpr==1 );
  if( pOrderBy->a[0].sortFlags & KEYINFO_ORDER_DESC ){
  if( pOrderBy->a[0].fg.sortFlags & KEYINFO_ORDER_DESC ){
    switch( op ){
      case OP_Ge: op = OP_Le; break;
      case OP_Gt: op = OP_Lt; break;
      default: assert( op==OP_Le ); op = OP_Ge; break;
    }
    arith = OP_Subtract;
  }

  **   }else if( reg2 IS NULL ){
  **     if( op==OP_Le ) goto lbl;
  **   }
  **
  ** Additionally, if either reg1 or reg2 are NULL but the jump to lbl is 
  ** not taken, control jumps over the comparison operator coded below this
  ** block.  */
  if( pOrderBy->a[0].sortFlags & KEYINFO_ORDER_BIGNULL ){
  if( pOrderBy->a[0].fg.sortFlags & KEYINFO_ORDER_BIGNULL ){
    /* This block runs if reg1 contains a NULL. */
    int addr = sqlite3VdbeAddOp1(v, OP_NotNull, reg1); VdbeCoverage(v);
    switch( op ){
      case OP_Ge: 
        sqlite3VdbeAddOp2(v, OP_Goto, 0, lbl); 
        break;
      case OP_Gt: