Clive Boughton <clive(dot)boughton(at)softimp(dot)com(dot)au> writes:
> When I recently upgraded to PG 18.1 (without any changes to the DB functions or tables, or indexing) it took 7-10 hours to produce the same result - a 300-600 times decrease in performance.
This complaint is completely un-actionable for lack of relevant
details. There are some hints here about describing performance
problems usefully:
https://wiki.postgresql.org/wiki/Slow_Query_Questions
regards, tom lane