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Add test cases and fix bugs associated with the previous check-in

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enhancements to nested aggregate subquery processing.

FossilOrigin-Name: 00b1dc71be4c3420730b5f7840af824ea86165e7
This commit is contained in:
drh
2012-08-23 19:46:11 +00:00
parent 030796df8d
commit ed551b95a4
6 changed files with 98 additions and 46 deletions
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41
src/resolve.c
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@@ -18,6 +18,29 @@
#include <stdlib.h>
#include <string.h>
/*
** Walk the expression tree pExpr and increase the aggregate function
** depth (the Expr.op2 field) by N on every TK_AGG_FUNCTION node.
** This needs to occur when copying a TK_AGG_FUNCTION node from an
** outer query into an inner subquery.
**
** incrAggFunctionDepth(pExpr,n) is the main routine. incrAggDepth(..)
** is a helper function - a callback for the tree walker.
*/
static int incrAggDepth(Walker *pWalker, Expr *pExpr){
if( pExpr->op==TK_AGG_FUNCTION ) pExpr->op2 += pWalker->u.i;
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.i = N;
sqlite3WalkExpr(&w, pExpr);
}
}
/*
** Turn the pExpr expression into an alias for the iCol-th column of the
** result set in pEList.
@@ -44,13 +67,20 @@
** The result of random()%5 in the GROUP BY clause is probably different
** from the result in the result-set. We might fix this someday. Or
** then again, we might not...
**
** The nSubquery parameter specifies how many levels of subquery the
** alias is removed from the original expression. The usually value is
** zero but it might be more if the alias is contained within a subquery
** of the original expression. The Expr.op2 field of TK_AGG_FUNCTION
** structures must be increased by the nSubquery amount.
*/
static void resolveAlias(
Parse *pParse, /* Parsing context */
ExprList *pEList, /* A result set */
int iCol, /* A column in the result set. 0..pEList->nExpr-1 */
Expr *pExpr, /* Transform this into an alias to the result set */
const char *zType /* "GROUP" or "ORDER" or "" */
const char *zType, /* "GROUP" or "ORDER" or "" */
int nSubquery /* Number of subqueries that the label is moving */
){
Expr *pOrig; /* The iCol-th column of the result set */
Expr *pDup; /* Copy of pOrig */
@@ -63,6 +93,7 @@ static void resolveAlias(
db = pParse->db;
if( pOrig->op!=TK_COLUMN && zType[0]!='G' ){
pDup = sqlite3ExprDup(db, pOrig, 0);
incrAggFunctionDepth(pDup, nSubquery);
pDup = sqlite3PExpr(pParse, TK_AS, pDup, 0, 0);
if( pDup==0 ) return;
if( pEList->a[iCol].iAlias==0 ){
@@ -151,9 +182,10 @@ static int lookupName(
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 i, j; /* Loop counters */
int cnt = 0; /* Number of matching column names */
int cntTab = 0; /* Number of matching table names */
int nSubquery = 0; /* How many levels of subquery */
sqlite3 *db = pParse->db; /* The database connection */
struct SrcList_item *pItem; /* Use for looping over pSrcList items */
struct SrcList_item *pMatch = 0; /* The matching pSrcList item */
@@ -315,7 +347,7 @@ static int lookupName(
sqlite3ErrorMsg(pParse, "misuse of aliased aggregate %s", zAs);
return WRC_Abort;
}
resolveAlias(pParse, pEList, j, pExpr, "");
resolveAlias(pParse, pEList, j, pExpr, "", nSubquery);
cnt = 1;
pMatch = 0;
assert( zTab==0 && zDb==0 );
@@ -329,6 +361,7 @@ static int lookupName(
*/
if( cnt==0 ){
pNC = pNC->pNext;
nSubquery++;
}
}
@@ -859,7 +892,7 @@ int sqlite3ResolveOrderGroupBy(
resolveOutOfRangeError(pParse, zType, i+1, pEList->nExpr);
return 1;
}
resolveAlias(pParse, pEList, pItem->iOrderByCol-1, pItem->pExpr, zType);
resolveAlias(pParse, pEList, pItem->iOrderByCol-1, pItem->pExpr, zType,0);
}
}
return 0;