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Fix for select 1=1 or 2=2, select 1=1 and 2=2, and select sum(2+2).

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This commit is contained in:
Bruce Momjian
1997-12-22 05:42:25 +00:00
parent 78a055a659
commit d404f1006b
10 changed files with 69 additions and 56 deletions
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37
src/backend/optimizer/plan/planmain.c
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@@ -7,7 +7,7 @@
*
*
* IDENTIFICATION
* $Header: /cvsroot/pgsql/src/backend/optimizer/plan/planmain.c,v 1.12 1997/12/20 07:59:25 momjian Exp $
* $Header: /cvsroot/pgsql/src/backend/optimizer/plan/planmain.c,v 1.13 1997/12/22 05:42:04 momjian Exp $
*
*-------------------------------------------------------------------------
*/
@@ -69,7 +69,7 @@ query_planner(Query *root,
List *qual)
{
List *constant_qual = NIL;
List *flattened_tlist = NIL;
List *var_only_tlist = NIL;
List *level_tlist = NIL;
Plan *subplan = (Plan *) NULL;
@@ -109,16 +109,12 @@ query_planner(Query *root,
* Create a target list that consists solely of (resdom var) target
* list entries, i.e., contains no arbitrary expressions.
*/
flattened_tlist = flatten_tlist(tlist);
if (flattened_tlist)
{
level_tlist = flattened_tlist;
}
var_only_tlist = flatten_tlist(tlist);
if (var_only_tlist)
level_tlist = var_only_tlist;
else
{
/* from old code. the logic is beyond me. - ay 2/95 */
level_tlist = tlist;
}
/*
* A query may have a non-variable target list and a non-variable
@@ -126,7 +122,7 @@ query_planner(Query *root,
* all-new tuples, or - the query is a replace (a scan must still be
* done in this case).
*/
if (flattened_tlist == NULL && qual == NULL)
if (var_only_tlist == NULL && qual == NULL)
{
switch (command_type)
@@ -192,11 +188,30 @@ query_planner(Query *root,
return (plan);
}
/*
* fix up the flattened target list of the plan root node so that
* expressions are evaluated. this forces expression evaluations that
* may involve expensive function calls to be delayed to the very last
* stage of query execution. this could be bad. but it is joey's
* responsibility to optimally push these expressions down the plan
* tree. -- Wei
*
* But now nothing to do if there are GroupBy and/or Aggregates: 1.
* make_groupPlan fixes tlist; 2. flatten_tlist_vars does nothing with
* aggregates fixing only other entries (i.e. - GroupBy-ed and so
* fixed by make_groupPlan). - vadim 04/05/97
*/
if (root->groupClause == NULL && root->qry_aggs == NULL)
{
subplan->targetlist = flatten_tlist_vars(tlist,
subplan->targetlist);
}
#ifdef NOT_USED
/*
* Destructively modify the query plan's targetlist to add fjoin lists
* to flatten functions that return sets of base types
*/
#ifdef NOT_USED
subplan->targetlist = generate_fjoin(subplan->targetlist);
#endif