Re: Query hangs (and then timeout) after using COPY to import data

On 2/11/24 15:13, steott(at)gmail(dot)com wrote:
> Thanks, Adrian, for the suggestion, but same problem.
>
> I've just tried to execute "ANALYZE" (on the whole database) after the import of all the tables (with COPY) and before the other queries, but the query always hangs (I hope this was the way you suggested).

Yes, this is what I was suggesting. Anytime I see data migration and
slow queries, my first suggestion is to run ANALYZE to get the planner
statistics up to date. That at least eliminates one possible source of
slowness. In this case though there seems to be something else at work,
see Tom Lanes suggestion. This may end up requiring installing auto-explain:

https://www.postgresql.org/docs/current/auto-explain.html

to get an EXPLAIN of the query.

>
> Stefano

--
Adrian Klaver
adrian(dot)klaver(at)aklaver(dot)com