On Thu, 30 Mar 2023, 05:03 Andrey Klochkov, <digg...@gmail.com> wrote:
> BRIN indexes seem to work perfectly well for our purposes, and they are so > tiny compared to B-Tree. Selecting min/max values is very expensive though. > > In my case the table is ~2.5TB (530M records), while the whole BRIN index > is 16MB. I think it'd be totally fine to scan all BRIN pages, it'd be way > better than doing table scan. > brin indexes don't work the way you would hope for. the stored min/max values per range guarantees that all values in the underlying relation pages are contained in that range, but it doesn't mean that those min/max values are still present in the table, so you can't deduce in which range the current min or max value is from there. >
