Richard Guo e01b23b84e Add an enable_groupagg GUC parameter ... We've long had enable_hashagg to discourage hashed aggregation, but there was no equivalent for grouping that works by reading presorted input. That's handy when investigating planner cost misestimates, and as an escape hatch when a sorted grouping plan is chosen over a much cheaper hashed one. enable_groupagg (on by default) covers the GroupAggregate and Group nodes, the sort-based Unique step used for DISTINCT and semijoin unique-ification, and the sorted mode of SetOp. It isn't a hard switch; it only bumps disabled_nodes, so plans with no other choice are still produced. Several regression and module tests had been setting enable_sort off, and one enable_indexscan off, only to force a hashed plan. Use enable_groupagg there instead, where that was the real intent. In union.sql this also lets us test the hashed UNION path, which we had no way to reach before. Author: Tatsuro Yamada <yamatattsu@gmail.com> Co-authored-by: Richard Guo <guofenglinux@gmail.com> Reviewed-by: Ashutosh Bapat <ashutosh.bapat.oss@gmail.com> Reviewed-by: David Rowley <dgrowleyml@gmail.com> Discussion: https://postgr.es/m/CAOKkKFvYHSEsFazkrf9bRH14p-H27XMaqbZfRYjS6EHBruvZMQ@mail.gmail.com		2026-07-09 09:44:56 +09:00
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hstore.sql	Add an enable_groupagg GUC parameter	2026-07-09 09:44:56 +09:00
hstore_utf8.sql	Handle \v as a whitespace character in parsers	2023-07-06 08:16:24 +09:00