On Tue, Jun 18, 2024 at 8:49 PM Masahiko Sawada <sawada.m...@gmail.com> wrote: > > At least I couldn't find anywhere in the docs where we have > > described the relationship between these columns before. Thoughts? > > It would be a good idea to improve the documentation, but I think that > we cannot simply compare these two numbers since the numbers that > these fields count are slightly different. For instance, > pg_stat_all_tables.n_dead_tup includes the number of dead tuples that > are going to be HOT-pruned.
This isn't a small difference. It's actually a huge one in many cases: https://www.postgresql.org/message-id/cah2-wzkkgt2gt4xaus5eqoqi4mvvl5x49hbttwccc8deqen...@mail.gmail.com Practically speaking they're just two different things, with hardly any fixed relationship. -- Peter Geoghegan