Re: partition pruning only works for select but update

On Fri, Jul 01, 2022 at 08:30:40AM +0000, James Pang (chaolpan) wrote:
> We have other application depend on V13, possible to backport code changes to V13 as https://git.postgresql.org/gitweb/?p=postgresql.git;a=patch;h=86dc90056dfdbd9d1b891718d2e5614e3e432f35

Do you mean that the other application needs to be updated to work with v14?
Or that you haven't checked yet if they work with v14?

In any case, I'm sure the feature won't be backpatched to v13 - it's an
improvement but not a bugfix.

--
Justin

> -----Original Message-----
> From: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
> Sent: Tuesday, June 28, 2022 9:30 PM
> To: James Pang (chaolpan) <chaolpan(at)cisco(dot)com>
> Cc: pgsql-performance(at)lists(dot)postgresql(dot)org
> Subject: Re: partition pruning only works for select but update
>
> "James Pang (chaolpan)" <chaolpan(at)cisco(dot)com> writes:
> > But when
> > Explain update table set .. where partitionkey between to_timestamp() and to_timestamp();
> > It still show all of partitions with update ...
>
> In releases before v14, partition pruning is far stupider for UPDATE (and DELETE) than it is for SELECT.