vacuuming - doubt - Mailing list pgsql-general

From Jayadevan M
Subject vacuuming - doubt
Date
Msg-id CAFS1N4i2xYDmAHinX9SFukkddvm6druwZ146mVYCKc7yUJ8Ksw@mail.gmail.com
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Responses Re: vacuuming - doubt  (Scott Marlowe <scott.marlowe@gmail.com>)
List pgsql-general
Hi,
Another theory question -
PostgreSQL documentation says that -
"There are two variants of VACUUM: standard VACUUM and VACUUM FULL. VACUUM FULL can reclaim more disk space "
I created a table, inserted 1000 records and deleted them. The size after a vacuum and a vacuum full are given -
select pg_total_relation_size('myt');;
 pg_total_relation_size
------------------------
                  65536
(1 row)

accounts=> vacuum   myt;
VACUUM

accounts=> select pg_total_relation_size('myt');;
 pg_total_relation_size
------------------------
                  16384
(1 row)

accounts=> vacuum  full myt;
VACUUM
accounts=> select pg_total_relation_size('myt');;
 pg_total_relation_size
------------------------
                      0
(1 row)

So what was the 65536 bytes left behind after standard vacuum?

Regards,
Jayadevan

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