Ken Winter <ken@xxxxxxxxxxx> writes: > I just discovered that a run of pg_dump that gets aborted empties any pre-existing backup file of the same name. It happens whether the run was deliberately canceled > by the user or just failed because of a bad password (as in the example below). > > ~/dba$ pg_dump --host=localhost -U ken --format=c --file=mess_development.bak --no-owner --no-privileges mess_development > Password: <CORRECT PASSWORD ENTERED> > > ~/dba$ ls -l mess_development.bak > -rw-rw-r-- 1 ken ken 87070 May 26 14:20 mess_development.bak > > ~/dba$ pg_dump --host=localhost -U ken --format=c --file=mess_development.bak --no-owner --no-privileges mess_development > Password: <BAD PASSWORD ENTERED> > pg_dump: [archiver (db)] connection to database "mess_development" failed: FATAL: password authentication failed for user "ken" > FATAL: password authentication failed for user "ken" >  > ~/dba$ ls -l mess_development.bak > -rw-rw-r-- 1 ken ken 0 May 26 14:21 mess_development.bak > > ~/dba$ > > This is troubling because I can imagine a disaster scenario where one loses one's previous backup and, perhaps because of a forgotten password, can't generate a new > one. (This scenario hasn't happened to me yet, but seems like it could.) In general, a failed run of a piece of software should leave everything unchanged. So maybe > this is a bug that needs to be fixed? Fix it by not overwriting your existing backup each time. Yes, it could probably not trunc the file until at least getting a valid DB connection so this aspect could probably be improved. You are running a pretty old Pg version. I vaguely remember discussion about pg_dump or some other utility truncing files a bit prematurely but it was long ago. But it can't know beyond that point if something else is going to cause the backup to abort. And I would not expect pg_dump to create a new file alongside your old file just in case since this can so easily be implemented in whatever framework you are launching pg_dump with. HTH > ~ Ken > -- Jerry Sievers Postgres DBA/Development Consulting e: postgres.consulting@xxxxxxxxxxx p: 312.241.7800 -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
