Fix inappropriate attempt to push down qual clauses into a view that

has UNION/INTERSECT/EXCEPT operations.  Per bug report from Ferrier.
This commit is contained in:
Tom Lane 2001-02-03 21:17:52 +00:00
parent 67849c84d6
commit 503f042cd7
1 changed files with 43 additions and 33 deletions

View File

@ -8,7 +8,7 @@
*
*
* IDENTIFICATION
* $Header: /cvsroot/pgsql/src/backend/optimizer/path/allpaths.c,v 1.70 2001/01/24 19:42:57 momjian Exp $
* $Header: /cvsroot/pgsql/src/backend/optimizer/path/allpaths.c,v 1.71 2001/02/03 21:17:52 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -101,8 +101,6 @@ set_base_rel_pathlists(Query *root)
if (rel->issubquery)
{
/* Subquery --- generate a separate plan for it */
List *upperrestrictlist;
List *lst;
/*
* If there are any restriction clauses that have been attached
@ -118,6 +116,11 @@ set_base_rel_pathlists(Query *root)
* Currently, we do not push down clauses that contain subselects,
* mainly because I'm not sure it will work correctly (the
* subplan hasn't yet transformed sublinks to subselects).
* Also, if the subquery contains set ops (UNION/INTERSECT/EXCEPT)
* we do not push down any qual clauses, since the planner doesn't
* support quals at the top level of a setop. (With suitable
* analysis we could try to push the quals down into the component
* queries of the setop, but getting it right is not trivial.)
* Non-pushed-down clauses will get evaluated as qpquals of
* the SubqueryScan node.
*
@ -125,41 +128,48 @@ set_base_rel_pathlists(Query *root)
* decision not to push down, because it'd result in a worse
* plan?
*/
upperrestrictlist = NIL;
foreach(lst, rel->baserestrictinfo)
if (rte->subquery->setOperations == NULL)
{
RestrictInfo *rinfo = (RestrictInfo *) lfirst(lst);
Node *clause = (Node *) rinfo->clause;
/* OK to consider pushing down individual quals */
List *upperrestrictlist = NIL;
List *lst;
if (contain_subplans(clause))
foreach(lst, rel->baserestrictinfo)
{
/* Keep it in the upper query */
upperrestrictlist = lappend(upperrestrictlist, rinfo);
}
else
{
/*
* We need to replace Vars in the clause (which must
* refer to outputs of the subquery) with copies of the
* subquery's targetlist expressions. Note that at this
* point, any uplevel Vars in the clause should have been
* replaced with Params, so they need no work.
*/
clause = ResolveNew(clause, rti, 0,
rte->subquery->targetList,
CMD_SELECT, 0);
rte->subquery->havingQual =
make_and_qual(rte->subquery->havingQual,
clause);
/*
* We need not change the subquery's hasAggs or
* hasSublinks flags, since we can't be pushing down
* any aggregates that weren't there before, and we
* don't push down subselects at all.
*/
RestrictInfo *rinfo = (RestrictInfo *) lfirst(lst);
Node *clause = (Node *) rinfo->clause;
if (contain_subplans(clause))
{
/* Keep it in the upper query */
upperrestrictlist = lappend(upperrestrictlist, rinfo);
}
else
{
/*
* We need to replace Vars in the clause (which must
* refer to outputs of the subquery) with copies of
* the subquery's targetlist expressions. Note that
* at this point, any uplevel Vars in the clause
* should have been replaced with Params, so they
* need no work.
*/
clause = ResolveNew(clause, rti, 0,
rte->subquery->targetList,
CMD_SELECT, 0);
rte->subquery->havingQual =
make_and_qual(rte->subquery->havingQual,
clause);
/*
* We need not change the subquery's hasAggs or
* hasSublinks flags, since we can't be pushing down
* any aggregates that weren't there before, and we
* don't push down subselects at all.
*/
}
}
rel->baserestrictinfo = upperrestrictlist;
}
rel->baserestrictinfo = upperrestrictlist;
/* Generate the plan for the subquery */
rel->subplan = subquery_planner(rte->subquery,