Dmitry Karasik <dmitry(at)karasik(dot)eu(dot)org> writes:
> I need to have a sort of a time machine, where select statements on tables
> could be easily replaced to select statements on tables as they were some time in the past,
> including all related table. To do so, I used views (see in the script) that UNION
> both current and archive tables and filter them by a timestamp.
If you use UNION ALL instead of UNION, you should get better results
(as well as inherently cheaper queries, since no duplicate-elimination
step will be needed).
regards, tom lane