Michal Taborsky wrote:
...
> UNION
...
> The result is sequential scan on all tables, append, sort and then
> filter scan on this whole thing. Which of course is slow as hell. We use
> version 8.0.2.
>
> And now the question: Is there a way to force the planner to push the
> condition lower, so it will use the index? Or do you use some tricks in
> this scenario? Thanks for your suggestions.
Try "UNION ALL", since UNION is defined as removing duplicates, which
probably accounts for the sort.
--
Richard Huxton
Archonet Ltd