Re: NOT IN subquery optimization
Zheng (Zane) Li <zhelli@amazon.com>
From: zhengli <zhelli@amazon.com>
To: pgsql-hackers@postgresql.org
Date: 2019-06-14T21:38:24Z
Lists: pgsql-hackers
In our patch, we only proceed with the ANTI JOIN transformation if subplan_is_hashable(subplan) is false, it requires the subquery to be planned at this point. To avoid planning the subquery again later on, I want to keep a pointer of the subplan in SubLink so that we can directly reuse the subplan when needed. However, this change breaks initdb for some reason and I'm trying to figure it out. I'll send the rebased patch in the following email since it's been a while. -- Sent from: http://www.postgresql-archive.org/PostgreSQL-hackers-f1928748.html
Commits
-
Check we don't misoptimize a NOT IN where the subquery returns no rows.
- 3396138a6de3 12.0 landed