database/postgres
1
0
Fork 0
mirror of https://github.com/postgres/postgres.git synced 2025-06-20 15:22:23 +03:00
Code Activity

Refactor planner's pathkeys data structure to create a separate, explicit

Browse Source 
representation of equivalence classes of variables.  This is an extensive
rewrite, but it brings a number of benefits:
* planner no longer fails in the presence of "incomplete" operator families
that don't offer operators for every possible combination of datatypes.
* avoid generating and then discarding redundant equality clauses.
* remove bogus assumption that derived equalities always use operators
named "=".
* mergejoins can work with a variety of sort orders (e.g., descending) now,
instead of tying each mergejoinable operator to exactly one sort order.
* better recognition of redundant sort columns.
* can make use of equalities appearing underneath an outer join.
This commit is contained in:
Tom Lane
2007-01-20 20:45:41 +00:00
parent 2b7334d487
commit f41803bb39
35 changed files with 3882 additions and 2719 deletions
Download Patch File Download Diff File Expand all files Collapse all files

3
src/backend/parser/parse_agg.c
View File

@ -8,7 +8,7 @@
*
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/parser/parse_agg.c,v 1.75 2007/01/05 22:19:33 momjian Exp $
* $PostgreSQL: pgsql/src/backend/parser/parse_agg.c,v 1.76 2007/01/20 20:45:40 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -171,6 +171,7 @@ parseCheckAggregates(ParseState *pstate, Query *qry)
{
root = makeNode(PlannerInfo);
root->parse = qry;
root->planner_cxt = CurrentMemoryContext;
root->hasJoinRTEs = true;
groupClauses = (List *) flatten_join_alias_vars(root,