On Wed, 11 May 2022 at 20:02, David Gauthier <dfgpostg...@gmail.com> wrote: > 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?
We have a similar situation, and run a weekly task that backs up the table, sets the outdated records to NULL, truncates the original table, then copies the records back in. With this approach the disk space is reclaimed immediately. The table is only written to by automated processes, so we have a weekly maintenance window where these aren't running. This might be a possible approach.
