On Wed, Oct 30, 2024 at 10:35 AM Peter Geoghegan <p...@bowt.ie> wrote:
> On Wed, Oct 30, 2024 at 11:24 AM Don Seiler <d...@seiler.us> wrote: > > One thing worth mentioning is that the table is 4 columns, the index is > on two of them and includes the other two. I can't think of an explanation > for the index being so much larger than its table, especially compared to > last month's index. > > > > Curious if anyone has any thoughts on what might be causing this. > > You mentioned that this has 4 columns. Sounds like this could be a > "locally monotonically increasing index". I wonder if you're > benefiting from this optimization, though only inconsistently: > > https://www.youtube.com/watch?v=p5RaATILoiE&t=2079s > https://git.postgresql.org/gitweb/?p=postgresql.git;a=commit;h=f21668f3 > > Of course, this is only a guess. I vaguely recall a complaint that > sounded vaguely like yours, also involving partitioning. > Thanks Peter, I'll look into that shortly. I should have also included that this is on PG 15 (currently 15.8 but we created the indexes when it was still 15.7) on Ubuntu 22.04 LTS. Don. -- Don Seiler www.seiler.us
