Thread

Re: BUG #19357: PostgreSQL generates a custom plan that performsworsethan the generic plan for a certain query.

Greg Sabino Mullane <htamfids@gmail.com> — 2025-12-17T17:11:07Z

Everything in the second query is slightly faster (and heavy emphasis on
"slightly") - it could simply be caching at some level. Run each query
multiple times and interleave them for better results. However, we are now
discussing that a query runs in .017ms versus .033ms. Add some real data
and demonstrate something that would trigger a real-world concern. Nobody
is going to get excited about microsecond differences. At that level, it's
near impossible to distinguish anything due to the overall noise and
effects of things out of Postgres' control. In short, not a bug, unless you
can demonstrate otherwise. :)


Cheers,
Greg