Is it true that one datafile in PG can only belong to one object (table/index) On Tue, Aug 23, 2016 at 9:55 AM, Francisco Olarte <folarte@xxxxxxxxxxxxxx> wrote: > On Tue, Aug 23, 2016 at 2:32 PM, Ilya Kazakevich > <Ilya.Kazakevich@xxxxxxxxxxxxx> wrote: >>>does that mean that I should always execute a VACUUM to recover the >>>wasted space when an error is triggered or will the auto-vacuum mechanism >>>do the job by itself ? >> If you have autovacuum enabled it will clean up tablespace. However, space will not be returned to filesystem but will be reused by database. >> You may run VACUUM FULL manually to return it to filesystem. > > A normal vacuum may also return some space, specially after a big bulk > load, see second paragraph of 23.1.2 the URL you posted: >> https://www.postgresql.org/docs/9.1/static/routine-vacuuming.html > > Where it says "However, it will not return the space to the operating > system, except in the special case where one or more pages at the end > of a table become entirely free and an exclusive table lock can be > easily obtained.". A big aborted bulk load may just fit the case, as > it may put a lot of tuples at new pages at the end and be executed in > a low-load period where the lock is easier to acquire. > > > Francisco Olarte. > > > -- > Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) > To make changes to your subscription: > http://www.postgresql.org/mailpref/pgsql-general -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
