Re: [COMMITTERS] pgsql: Simplify plpgsql's check for simple expressions.
Tom Lane <tgl@sss.pgh.pa.us>
From: Tom Lane <tgl@sss.pgh.pa.us>
To: Robert Haas <robertmhaas@gmail.com>
Cc: "pgsql-hackers@postgresql.org" <pgsql-hackers@postgresql.org>
Date: 2017-08-16T16:49:32Z
Lists: pgsql-hackers
Robert Haas <robertmhaas@gmail.com> writes: > On Wed, Aug 16, 2017 at 11:56 AM, Tom Lane <tgl@sss.pgh.pa.us> wrote: >> I can get on board with that statement. Can you draft a better wording? > Here is an attempt. Feel free to edit. I think s/plan/query/ in the last bit would be better. Perhaps + * However, if force_parallel_mode = on or force_parallel_mode = regress, + * then we impose parallel mode whenever it's safe to do so, even if the + * final plan doesn't use parallelism. It's not safe to do so if the query + * contains anything parallel-unsafe; parallelModeOK will be false in that + * case. Otherwise, everything in the query is either parallel-safe or + * parallel-restricted, and in either case it should be OK to impose + * parallel-mode restrictions. If that ends up breaking something, then + * either some function the user included in the query is incorrectly + * labelled as parallel-safe or parallel-restricted when in reality it's + * parallel-unsafe, or else the query planner itself has a bug. */ regards, tom lane
Commits
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Attempt to clarify comments related to force_parallel_mode.
- 1e56883a528e 11.0 landed
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Make simpler-simple-expressions code cope with a Gather plan.
- b73f1b5c29e0 11.0 landed
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Simplify plpgsql's check for simple expressions.
- 00418c612441 11.0 cited