Re: Bad Estimate for complex query with JOINS on subselects and OR in where conditions - Mailing list pgsql-general

Peter Grman <peter.grman@gmail.com> writes:
> yes, I think this query is right below the geqo_threshold. But as I said,
> when I change only the WHERE condition to use AND instead of OR it's
> resulting in a really fast and efficient query (same planning time, but
> ~1/500th-1/1000th execution time). So there should be something different,
> or?

Don't really see why that would surprise you.  Using AND means that the
individual conditions can be applied as filters, if the planner knows
how to use any one of them as (say) an indexscan or join qual.  When
you use OR, that isn't possible.

            regards, tom lane