On Sun, 15 Aug 2021 at 23:41, otar shavadze <oshava...@gmail.com> wrote: > SELECT > (SELECT relpages FROM pg_class where oid = 'public.my_table'::regclass::oid ) > AS table_pages_quantity_total, > (SELECT COUNT(DISTINCT relblocknumber) FROM pg_buffercache WHERE relfilenode > = ( > SELECT relfilenode FROM pg_class WHERE oid = 'public.my_table'::regclass::oid > -- (SELECT rel_oid FROM my_cte) > ) ) AS table_pages_quantity_in_cache; > > This shows that table have only one page, while second column shows 3 unique > pages in buffer cache. Seems I'm measuring those numbers incorrectly(?) can > you please help, which column is incorrect (or may be both) ?
This question likely is more suited to the pgsql-general mailing list. My answer in [1] likely will clear this up for you. If you need further information, please ask on that thread. David [1] https://www.postgresql.org/message-id/caaphdvphddfozoviyxiz2dcr9emrrbnj7n3hks8knsd9w1w...@mail.gmail.com
