Date: Mon, 23 Jul 2018 13:43:19 -0700
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References: <20180723203311.7isul7yxziiw7wbx@alvherre.pgsql>
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Subject: Re: pg_authid has duplicated rows
To: Alvaro Herrera <alvherre@2ndquadrant.com>
CC: Mariel Cherkassky
 <mariel.cherkassky@gmail.com>,pgsql-admin@lists.postgresql.org
From: Andres Freund <andres@anarazel.de>
Message-ID: <CA916A7F-0469-45B5-9AC3-1AC0F5CCB859@anarazel.de>
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On July 23, 2018 1:33:11 PM PDT, Alvaro Herrera <alvherre@2ndquadrant=2Eco=
m> wrote:
>On 2018-Jul-23, Andres Freund wrote:
>
>> Hi,
>>=20
>> On 2018-07-23 21:03:32 +0300, Mariel Cherkassky wrote:
>> > Today I faced a situation where I saw a postgresql 9=2E2 database
>that had
>> > duplicated rows in pg_autid=2E I saw 6 roles while 3 of them were
>duplicated
>> > (3 uniques rolenames in total)=2E I checked and the oid of the
>duplicates
>> > were the same oid as the originals=2E The solution was running vacuum
>on the
>> > table but I wanted to understand how this situation was created ?
>Why even
>> > with unique index on the rolname I saw duplicated values for
>rolname ?
>>=20
>> That suggests some form of corruption=2E Which version of 9=2E2 did thi=
s
>> occur on? Did you have any OS level crashes? Ran with fsync=3Doff?
>
>I have vague memories of seeing this recently=2E  Can you please show=20

It's at least one of the potential effects of the out-of-date shared relca=
che bug I recently fixed (but wasn't backpatched to 9=2E2, as it's unsuppor=
ted)=2E

Andres

--=20
Sent from my Android device with K-9 Mail=2E Please excuse my brevity=2E