> On Jan 30, 2024, at 4:40 AM, Pavlos Kallis <pkal...@yourhero.com> wrote:
>
> Shouldn't VACUUM ANALYZE reclaim the disk space?
Hi Pavlos,
The short answer to this is “no”. That’s an important difference between VACUUM
(also known as “plain” VACUUM) and VACUUM FULL. In some special cases plain
VACUUM can reclaim disk space, but I think both the circumstances under which
it can do so and the amount it can reclaim are pretty limited. An
oversimplified but "mostly correct" way to think about it is that plain VACUUM
can't reclaim disk space, whereas VACUUM FULL can.
This is covered in the 4th paragraph of the doc of the VACUUM command --
https://www.postgresql.org/docs/current/sql-vacuum.html
So in your case those 5m rows that you deleted were probably still clogging up
your table until you ran VACUUM FULL.
Hope this helps
Philip
