Doesn't vacuum run automatically (or can it be set to run automatically) ?
On Wed, May 11, 2022 at 8:05 PM David G. Johnston < david.g.johns...@gmail.com> wrote: > On Wednesday, May 11, 2022, David Gauthier <dfgpostg...@gmail.com> wrote: > >> Hi: >> psql (11.5, server 11.3) on linux >> >> I have a table with a bytea column which, of course, contains binary >> data. After 60 days, I no longer need the binary data but want to retain >> the rest of the record. Of course it's easy to just update the bytea >> column to null for the older records. But I can almost imagine this record >> on disk with a big "hole" in the middle where the bytea data used to be. >> Is there a PG daemon (the vacuum ?) that will "heal the hole" in time? >> >> > The freshly written record will not have a hole - either by virtue of > variable width fields taking up basically their actual data space and also > the fact that null is treated specially in the record format. > > For the old row, yes you should read up on the how and why of the vacuum > command. > > David J. > >
