On Mon, 8 Apr 2019 at 10:09, Igal Sapir <igal@lucee.org> wrote: > > I have a table for which pg_relation_size() shows only 31MB, but pg_total_relation_size() shows a whopping 84GB. > > The database engine is running inside a Docker container, with the data mounted as a volume from a partition on the host's file system. > > When I try to run `VACUUM FULL`, the disk usage goes up until it reaches the full capacity of the partition (about 27GB of free space), at which point it fails.
That sort of indicates that the table might not be as bloated as you seem to think it is. Remember that variable length attributes can be toasted and stored in the relation's toast table.
I think that you're on to something here. The table has a JSONB column which has possibly toasted.
I have deleted many rows from the table itself though, and still fail to reclaim disk space. Is there something else I should do to delete the toasted data?