Re: Bug #807: Sequence currupted on recovery after kill -9
Bruce Momjian <pgman@candle.pha.pa.us>
From: Bruce Momjian <pgman@candle.pha.pa.us>
To: Robert Hentosh <hentosh@io.com>
Cc: mthomp@tierfleet.com, pgsql-bugs@postgresql.org
Date: 2002-10-29T18:54:22Z
Lists: pgsql-bugs
Robert Hentosh wrote: > On Tue, 29 Oct 2002 pgsql-bugs@postgresql.org wrote: > > > Matt Thompson (mthomp@tierfleet.com) reports a bug with a severity of 2 > > The lower the number the more severe it is. > > > > Short Description > > Sequence currupted on recovery after kill -9 > > > > Long Description > > If you create a file with an implied sequence and do a couple of inserts, then do a kill -9, when you start up again, the sequence will have a corrupted next_value field. In the example, the value of last_value is 4 before the kill -9 and 34 when it comes back up. > > > > > The purpose of a sequence is not to insure that the numbers are > consecutive, only to insure that they are unique. If you have failed > inserts, you will see holes also. > > I don't know off the top of my head how to do consecutive numbers. Maybe > only with a table lock. Right. Sequences aren't consecutive anyway because an ABORT will not reuse the sequence value. There is an FAQ on that. -- Bruce Momjian | http://candle.pha.pa.us pgman@candle.pha.pa.us | (610) 359-1001 + If your life is a hard drive, | 13 Roberts Road + Christ can be your backup. | Newtown Square, Pennsylvania 19073