On Tue, Jan 17, 2023 at 03:00:50PM -0600, Justin Pryzby wrote: > 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: > > > 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
Yes, I see that patch was trying to combine the statistics of individual partitions into a partitioned table summary. > Maybe (all?) the clarification the docs need is to say: > "Partitioned tables are not *themselves* processed by autovacuum." Yes, I think the lack of autovacuum needs to be specifically mentioned since most people assume autovacuum handles _all_ statistics updating. Can someone summarize how bad it is we have no statistics on partitioned tables? It sounds bad to me. -- Bruce Momjian <br...@momjian.us> https://momjian.us EDB https://enterprisedb.com Embrace your flaws. They make you human, rather than perfect, which you will never be.
