Ah, thanks for that On Fri, Oct 11, 2024 at 5:59 PM Adrian Klaver <adrian.kla...@aklaver.com> wrote:
> On 10/11/24 04:08, Koen De Groote wrote: > > In the release notes for postgres 17 I'm reading: > > > > > The PostgreSQL foreign data wrapper (postgres_fdw), used to execute > > queries on remote PostgreSQL instances, can now push EXISTS and IN > > subqueries to the remote server for more efficient processing. > > > > I'm confused as to what this means. In older versions, are parts of > > queries not sent to the foreign server? Or is this change meant to imply > > the sending of only the subqueries, the result of which is then directly > > used in pushing the entire query? > > > > Or am I still wrong as to what this means? > > > > I looked at the documentation and there doesn't seem to be any > > indication of particular queries not being pushed to the foreign server, > > so this wording that "can now push EXISTS and IN subqueries to the > > remote server" is confusing. > > > > What am I missing? > > Read: > > > https://www.postgresql.org/docs/current/postgres-fdw.html#POSTGRES-FDW-REMOTE-QUERY-OPTIMIZATION > > F.36.5. Remote Query Optimization > > > As to the change in the Release Note see the --hackers discussion: > > > https://www.postgresql.org/message-id/c9e2a757cf3ac2333714eaf83a9cc184%40postgrespro.ru > > > > > Regards, > > Koen De Groote > > -- > Adrian Klaver > adrian.kla...@aklaver.com > >
