On Tue, Jan 17, 2023 at 03:53:24PM -0500, Bruce Momjian wrote: > On Thu, Jan 12, 2023 at 03:27:47PM -0800, Nathan Bossart wrote: > > On Wed, Oct 05, 2022 at 10:37:01AM +0200, Laurenz Albe wrote: > > > On Mon, 2022-03-28 at 15:05 +0200, Tomas Vondra wrote: > > >> I've pushed the last version, and backpatched it to 10 (not sure I'd > > >> call it a bugfix, but I certainly agree with Justin it's worth > > >> mentioning in the docs, even on older branches). > > > > > > I'd like to suggest an improvement to this. The current wording could > > > be read to mean that dead tuples won't get cleaned up in partitioned > > > tables. > > > > Well, dead tuples won't get cleaned up in partitioned tables, as > > partitioned tables do not have storage. But I see what you mean. Readers > > might misinterpret this to mean that autovacuum will not process the > > partitions. There's a good definition of what the docs mean by > > "partitioned table" [0], but FWIW it took me some time before I > > consistently read "partitioned table" to mean "only the thing with relkind > > set to 'p'" and not "both the partitioned table and its partitions." So, > > while the current wording it technically correct, I think it'd be > > reasonable to expand it to help avoid confusion. > > > > Here is my take on the wording: > > > > Since all the data for a partitioned table is stored in its partitions, > > autovacuum does not process partitioned tables. Instead, autovacuum > > processes the individual partitions that are regular tables. This > > means that autovacuum only gathers statistics for the regular tables > > that serve as partitions and not for the partitioned tables. Since > > queries may rely on a partitioned table's statistics, you should > > collect statistics via the ANALYZE command when it is first populated, > > and again whenever the distribution of data in its partitions changes > > significantly. > > Uh, what about autovacuum's handling of partitioned tables? This makes > it sound like it ignores them because it talks about manual ANALYZE.
If we're referring to the *partitioned* table, then it does ignore them. See: |commit 6f8127b7390119c21479f5ce495b7d2168930e82 |Author: Alvaro Herrera <alvhe...@alvh.no-ip.org> |Date: Mon Aug 16 17:27:52 2021 -0400 | | Revert analyze support for partitioned tables Maybe (all?) the clarification the docs need is to say: "Partitioned tables are not *themselves* processed by autovacuum." -- Justin
