Re: Check each of base restriction clauses for constant-FALSE-or-NULL
Ashutosh Bapat <ashutosh.bapat.oss@gmail.com>
From: Ashutosh Bapat <ashutosh.bapat.oss@gmail.com>
To: Richard Guo <guofenglinux@gmail.com>
Cc: PostgreSQL-development <pgsql-hackers@postgresql.org>
Date: 2023-10-10T05:45:31Z
Lists: pgsql-hackers
On Tue, Oct 10, 2023 at 11:09 AM Richard Guo <guofenglinux@gmail.com> wrote: > Do you mean the const-folding? It happens in the preprocessing phase, > specifically in eval_const_expressions(). Thanks. > Hm, I don't think so. get_gating_quals is called in createplan.c, where > we've selected the best path, while the optimization with my code > happens much earlier, when we set size estimates for a base relation. > Neither of these two is a duplicate of the other. I think the theory > here is that it's always a win to mark a rel as dummy if possible as > early as we can. Right. Do you have an example where this could be demonstrated? -- Best Wishes, Ashutosh Bapat
Commits
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Fix missed optimization in relation_excluded_by_constraints().
- 5d8aa8bcedae 17.0 landed