Re: unstable query plan on pg 16,17,18 - Mailing list pgsql-performance

On 24 Feb 2026, at 12:09, Andrei Lepikhov <lepihov@gmail.com> wro
> This update gives us more useful details. In PG14, the join search problem involved at most 9 relations. In PG19, the
maximumis now 18 joins. Do you know what your join_collapse_limit is set to? It looks like subplan pull-ups have made
thingsmore complex. 
> First, we should look into any possible 'rescan cost' issues on our side as developers.
> On your end, please check the join_collapse_limit setting. If needed, try increasing it to around 20. This might
help.

join_collapse_limit is not set, so it is the default, 8
I will try if something around 20 helps.

thanks

btw: I working on providing more details to the query

regards,
Attila