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-rw-r--r--src/backend/optimizer/path/allpaths.c12
-rw-r--r--src/backend/optimizer/plan/planner.c46
-rw-r--r--src/backend/optimizer/prep/prepunion.c58
-rw-r--r--src/backend/optimizer/util/clauses.c12
-rw-r--r--src/include/optimizer/prep.h5
5 files changed, 78 insertions, 55 deletions
diff --git a/src/backend/optimizer/path/allpaths.c b/src/backend/optimizer/path/allpaths.c
index c7b5db73353..b01025a85d3 100644
--- a/src/backend/optimizer/path/allpaths.c
+++ b/src/backend/optimizer/path/allpaths.c
@@ -8,7 +8,7 @@
*
*
* IDENTIFICATION
- * $PostgreSQL: pgsql/src/backend/optimizer/path/allpaths.c,v 1.121 2004/08/29 05:06:43 momjian Exp $
+ * $PostgreSQL: pgsql/src/backend/optimizer/path/allpaths.c,v 1.122 2004/10/02 22:39:45 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@@ -124,8 +124,7 @@ set_base_rel_pathlists(Query *root)
/* RangeFunction --- generate a separate plan for it */
set_function_pathlist(root, rel, rte);
}
- else if ((inheritlist = expand_inherited_rtentry(root, rti, true))
- != NIL)
+ else if ((inheritlist = expand_inherited_rtentry(root, rti)) != NIL)
{
/* Relation is root of an inheritance tree, process specially */
set_inherited_rel_pathlist(root, rel, rti, rte, inheritlist);
@@ -224,13 +223,6 @@ set_inherited_rel_pathlist(Query *root, RelOptInfo *rel,
errmsg("SELECT FOR UPDATE is not supported for inheritance queries")));
/*
- * The executor will check the parent table's access permissions when
- * it examines the parent's inheritlist entry. There's no need to
- * check twice, so turn off access check bits in the original RTE.
- */
- rte->requiredPerms = 0;
-
- /*
* Initialize to compute size estimates for whole inheritance tree
*/
rel->rows = 0;
diff --git a/src/backend/optimizer/plan/planner.c b/src/backend/optimizer/plan/planner.c
index d8f228f2b94..1831c1bb9ca 100644
--- a/src/backend/optimizer/plan/planner.c
+++ b/src/backend/optimizer/plan/planner.c
@@ -8,7 +8,7 @@
*
*
* IDENTIFICATION
- * $PostgreSQL: pgsql/src/backend/optimizer/plan/planner.c,v 1.175 2004/08/30 02:54:38 momjian Exp $
+ * $PostgreSQL: pgsql/src/backend/optimizer/plan/planner.c,v 1.176 2004/10/02 22:39:46 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@@ -320,8 +320,7 @@ subquery_planner(Query *parse, double tuple_fraction)
* grouping_planner.
*/
if (parse->resultRelation &&
- (lst = expand_inherited_rtentry(parse, parse->resultRelation,
- false)) != NIL)
+ (lst = expand_inherited_rtentry(parse, parse->resultRelation)) != NIL)
plan = inheritance_planner(parse, lst);
else
plan = grouping_planner(parse, tuple_fraction);
@@ -513,7 +512,6 @@ inheritance_planner(Query *parse, List *inheritlist)
{
int childRTindex = lfirst_int(l);
Oid childOID = getrelid(childRTindex, parse->rtable);
- int subrtlength;
Query *subquery;
Plan *subplan;
@@ -526,22 +524,40 @@ inheritance_planner(Query *parse, List *inheritlist)
subplans = lappend(subplans, subplan);
/*
- * It's possible that additional RTEs got added to the rangetable
- * due to expansion of inherited source tables (see allpaths.c).
- * If so, we must copy 'em back to the main parse tree's rtable.
+ * XXX my goodness this next bit is ugly. Really need to think about
+ * ways to rein in planner's habit of scribbling on its input.
*
- * XXX my goodness this is ugly. Really need to think about ways to
- * rein in planner's habit of scribbling on its input.
+ * Planning of the subquery might have modified the rangetable,
+ * either by addition of RTEs due to expansion of inherited source
+ * tables, or by changes of the Query structures inside subquery
+ * RTEs. We have to ensure that this gets propagated back to the
+ * master copy. However, if we aren't done planning yet, we also
+ * need to ensure that subsequent calls to grouping_planner have
+ * virgin sub-Queries to work from. So, if we are at the last
+ * list entry, just copy the subquery rangetable back to the master
+ * copy; if we are not, then extend the master copy by adding
+ * whatever the subquery added. (We assume these added entries
+ * will go untouched by the future grouping_planner calls. We are
+ * also effectively assuming that sub-Queries will get planned
+ * identically each time, or at least that the impacts on their
+ * rangetables will be the same each time. Did I say this is ugly?)
*/
- subrtlength = list_length(subquery->rtable);
- if (subrtlength > mainrtlength)
+ if (lnext(l) == NULL)
+ parse->rtable = subquery->rtable;
+ else
{
- List *subrt;
+ int subrtlength = list_length(subquery->rtable);
+
+ if (subrtlength > mainrtlength)
+ {
+ List *subrt;
- subrt = list_copy_tail(subquery->rtable, mainrtlength);
- parse->rtable = list_concat(parse->rtable, subrt);
- mainrtlength = subrtlength;
+ subrt = list_copy_tail(subquery->rtable, mainrtlength);
+ parse->rtable = list_concat(parse->rtable, subrt);
+ mainrtlength = subrtlength;
+ }
}
+
/* Save preprocessed tlist from first rel for use in Append */
if (tlist == NIL)
tlist = subplan->targetlist;
diff --git a/src/backend/optimizer/prep/prepunion.c b/src/backend/optimizer/prep/prepunion.c
index 12d492f8038..ba1de1b8860 100644
--- a/src/backend/optimizer/prep/prepunion.c
+++ b/src/backend/optimizer/prep/prepunion.c
@@ -14,7 +14,7 @@
*
*
* IDENTIFICATION
- * $PostgreSQL: pgsql/src/backend/optimizer/prep/prepunion.c,v 1.116 2004/08/29 05:06:44 momjian Exp $
+ * $PostgreSQL: pgsql/src/backend/optimizer/prep/prepunion.c,v 1.117 2004/10/02 22:39:47 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@@ -705,24 +705,23 @@ find_all_inheritors(Oid parentrel)
* whole inheritance set (parent and children).
* If not, return NIL.
*
- * When dup_parent is false, the initially given RT index is part of the
- * returned list (if any). When dup_parent is true, the given RT index
- * is *not* in the returned list; a duplicate RTE will be made for the
- * parent table.
+ * Note that the original RTE is considered to represent the whole
+ * inheritance set. The first member of the returned list is an RTE
+ * for the same table, but with inh = false, to represent the parent table
+ * in its role as a simple member of the set. The original RT index is
+ * never a member of the returned list.
*
* A childless table is never considered to be an inheritance set; therefore
* the result will never be a one-element list. It'll be either empty
* or have two or more elements.
*
- * NOTE: after this routine executes, the specified RTE will always have
- * its inh flag cleared, whether or not there were any children. This
- * ensures we won't expand the same RTE twice, which would otherwise occur
- * for the case of an inherited UPDATE/DELETE target relation.
- *
- * XXX probably should convert the result type to Relids?
+ * Note: there are cases in which this routine will be invoked multiple
+ * times on the same RTE. We will generate a separate set of child RTEs
+ * for each invocation. This is somewhat wasteful but seems not worth
+ * trying to avoid.
*/
List *
-expand_inherited_rtentry(Query *parse, Index rti, bool dup_parent)
+expand_inherited_rtentry(Query *parse, Index rti)
{
RangeTblEntry *rte = rt_fetch(rti, parse->rtable);
Oid parentOID;
@@ -734,12 +733,14 @@ expand_inherited_rtentry(Query *parse, Index rti, bool dup_parent)
if (!rte->inh)
return NIL;
Assert(rte->rtekind == RTE_RELATION);
- /* Always clear the parent's inh flag, see above comments */
- rte->inh = false;
/* Fast path for common case of childless table */
parentOID = rte->relid;
if (!has_subclass(parentOID))
+ {
+ /* Clear flag to save repeated tests if called again */
+ rte->inh = false;
return NIL;
+ }
/* Scan for all members of inheritance set */
inhOIDs = find_all_inheritors(parentOID);
@@ -749,37 +750,42 @@ expand_inherited_rtentry(Query *parse, Index rti, bool dup_parent)
* table once had a child but no longer does.
*/
if (list_length(inhOIDs) < 2)
+ {
+ /* Clear flag to save repeated tests if called again */
+ rte->inh = false;
return NIL;
- /* OK, it's an inheritance set; expand it */
- if (dup_parent)
- inhRTIs = NIL;
- else
- inhRTIs = list_make1_int(rti); /* include original RTE in result */
+ }
+ /* OK, it's an inheritance set; expand it */
+ inhRTIs = NIL;
foreach(l, inhOIDs)
{
Oid childOID = lfirst_oid(l);
RangeTblEntry *childrte;
Index childRTindex;
- /* parent will be in the list too; skip it if not dup requested */
- if (childOID == parentOID && !dup_parent)
- continue;
-
/*
* Build an RTE for the child, and attach to query's rangetable
* list. We copy most fields of the parent's RTE, but replace
- * relation real name and OID. Note that inh will be false at
- * this point.
+ * relation OID, and set inh = false.
*/
childrte = copyObject(rte);
childrte->relid = childOID;
+ childrte->inh = false;
parse->rtable = lappend(parse->rtable, childrte);
childRTindex = list_length(parse->rtable);
-
inhRTIs = lappend_int(inhRTIs, childRTindex);
}
+ /*
+ * The executor will check the parent table's access permissions when
+ * it examines the parent's inheritlist entry. There's no need to
+ * check twice, so turn off access check bits in the original RTE.
+ * (If we are invoked more than once, extra copies of the child RTEs
+ * will also not cause duplicate permission checks.)
+ */
+ rte->requiredPerms = 0;
+
return inhRTIs;
}
diff --git a/src/backend/optimizer/util/clauses.c b/src/backend/optimizer/util/clauses.c
index de0e7a539c2..1f848cd9bdb 100644
--- a/src/backend/optimizer/util/clauses.c
+++ b/src/backend/optimizer/util/clauses.c
@@ -8,7 +8,7 @@
*
*
* IDENTIFICATION
- * $PostgreSQL: pgsql/src/backend/optimizer/util/clauses.c,v 1.180 2004/08/29 05:06:44 momjian Exp $
+ * $PostgreSQL: pgsql/src/backend/optimizer/util/clauses.c,v 1.181 2004/10/02 22:39:48 tgl Exp $
*
* HISTORY
* AUTHOR DATE MAJOR EVENT
@@ -3254,10 +3254,20 @@ query_tree_mutator(Query *query,
CHECKFLATCOPY(newrte->subquery, rte->subquery, Query);
MUTATE(newrte->subquery, newrte->subquery, Query *);
}
+ else
+ {
+ /* else, copy RT subqueries as-is */
+ newrte->subquery = copyObject(rte->subquery);
+ }
break;
case RTE_JOIN:
if (!(flags & QTW_IGNORE_JOINALIASES))
MUTATE(newrte->joinaliasvars, rte->joinaliasvars, List *);
+ else
+ {
+ /* else, copy join aliases as-is */
+ newrte->joinaliasvars = copyObject(rte->joinaliasvars);
+ }
break;
case RTE_FUNCTION:
MUTATE(newrte->funcexpr, rte->funcexpr, Node *);
diff --git a/src/include/optimizer/prep.h b/src/include/optimizer/prep.h
index 5284d224bcd..9f84d29f39a 100644
--- a/src/include/optimizer/prep.h
+++ b/src/include/optimizer/prep.h
@@ -7,7 +7,7 @@
* Portions Copyright (c) 1996-2004, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
- * $PostgreSQL: pgsql/src/include/optimizer/prep.h,v 1.45 2004/08/29 04:13:08 momjian Exp $
+ * $PostgreSQL: pgsql/src/include/optimizer/prep.h,v 1.46 2004/10/02 22:39:49 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@@ -52,8 +52,7 @@ extern Plan *plan_set_operations(Query *parse, List **sortClauses);
extern List *find_all_inheritors(Oid parentrel);
-extern List *expand_inherited_rtentry(Query *parse, Index rti,
- bool dup_parent);
+extern List *expand_inherited_rtentry(Query *parse, Index rti);
extern Node *adjust_inherited_attrs(Node *node,
Index old_rt_index, Oid old_relid,
generated by cgit v1.2.3 (git 2.25.1) at 2025-05-24 17:21:06 +0000