Skip site navigation (1) Skip section navigation (2)

Re: URGENT TABLE PG_SHADOW CORRUTEP

From: "Peter Koczan" <pjkoczan(at)gmail(dot)com>
To: "Tom Lane" <tgl(at)sss(dot)pgh(dot)pa(dot)us>
Cc: "Daniel Ricardo Medina" <dmedina(at)computec(dot)com(dot)co>, pgsql-admin(at)postgresql(dot)org
Subject: Re: URGENT TABLE PG_SHADOW CORRUTEP
Date: 2007-03-26 00:27:56
Message-ID: 4544e0330703251727xd988c1ue4de1494f79b8933@mail.gmail.com (view raw or flat)
Thread:
Lists: pgsql-admin
I saw something along these lines recently when I was running stuff from
postgres 7.4.7 (we recently upgraded to 8.2.3). Basically, a unique index
somehow fails and allows duplicate rows...but I don't know why.

Deleting doesn't work because postgres only looks for the record shown by
the index (though this may have been fixed in more recent releases). At
least this is the behaviour I observed.

The way I fixed it was to drop the unique index, remove the offending rows,
reinsert only one of the offending rows (so things would once again be
unique), and remake the index. It worked.

There are two things that concern me:
1. Trying to do this on a system table is likely ill-advised at best, and
dangerous at worst.
2. If the table only has 3 rows in it and it got corrupted, there's
something really wrong. My table in question was a user table that had
almost a million rows.

On 3/25/07, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
>
> "Daniel Ricardo Medina" <dmedina(at)computec(dot)com(dot)co> writes:
> > I have try to run this command in single user mod
> >
> > select * from pg_shadow;
> > delete from pg_shadow;
> > CREATE USER postgres WITH CREATEDB CREATEUSER PASSWORD '***' SYSID 1;
> > CREATE USER userradar PASSWORD '***'
>
> > but the result is the same.....
>
> What do you see if you look in pg_shadow right after doing the DELETE?
> What PG version is this?
>
>                         regards, tom lane
>
> ---------------------------(end of broadcast)---------------------------
> TIP 7: You can help support the PostgreSQL project by donating at
>
>                 http://www.postgresql.org/about/donate
>

In response to

Responses

pgsql-admin by date

Next:From: Tom LaneDate: 2007-03-26 00:57:47
Subject: Re: trying to run PITR recovery
Previous:From: Tom LaneDate: 2007-03-25 18:51:47
Subject: Re: URGENT TABLE PG_SHADOW CORRUTEP

Privacy Policy | About PostgreSQL
Copyright © 1996-2014 The PostgreSQL Global Development Group