Thread:
On Sun, Aug 15, 2021 at 12:49 PM otar shavadze <oshavadze@gmail.com> wrote:
How measure table total pages (block) count? would be this correct way? :SELECT pg_table_size('my_table'::regclass) / current_setting('block_size')::BIGINT;
Did you try:
SELECT relpages FROM pg_class WHERE relname='my_table';Best,
Michael
Thank you.
On Sun, Aug 15, 2021 at 2:15 PM Michael Goldberg <mic.goldberg@gmail.com> wrote:
On Sun, Aug 15, 2021 at 12:49 PM otar shavadze <oshavadze@gmail.com> wrote:How measure table total pages (block) count? would be this correct way? :SELECT pg_table_size('my_table'::regclass) / current_setting('block_size')::BIGINT;
Did you try:SELECT relpages FROM pg_class WHERE relname='my_table';Best,Michael
On Sun, 15 Aug 2021 at 22:15, Michael Goldberg <mic.goldberg@gmail.com> wrote: > > > On Sun, Aug 15, 2021 at 12:49 PM otar shavadze <oshavadze@gmail.com> wrote: >> >> How measure table total pages (block) count? would be this correct way? : >> >> SELECT pg_table_size('my_table'::regclass) / current_setting('block_size')::BIGINT; > > Did you try: > SELECT relpages FROM pg_class WHERE relname='my_table'; It might pay to have a quick glance at the documentation here [1]. It's important to know that relpages is *not* kept up-to-date every time the relation size increases. It's probably most commonly going to be updated by auto-analyze after the table has grown or changed enough for an auto-analyze to trigger. The actual answer to the question depends on what Otar wants to include when counting the number of blocks. pg_table_size() will count the TOAST table too. If that's what's required then Otar's original query looks fine. If not, the table in [2] is likely going to yield the answer. pg_relation_size() might be what's required. David [1] https://www.postgresql.org/docs/current/catalog-pg-class.html [2] https://www.postgresql.org/docs/current/functions-admin.html#FUNCTIONS-ADMIN-DBSIZE