From: raghavendra t <raagavendra.rao@gmail.com>
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: pgsql-general@postgresql.org
Subject: Re: ERROR: cache lookup failed for relation X
Date: Sun, 4 Apr 2010 08:20:12 +0530
Message-ID: <k2mbc7de5a31004031950pebd99d60t737c2d642b1b99fe@mail.gmail.com> (raw)
In-Reply-To: <21301.1270314309@sss.pgh.pa.us>
References: <h2xbc7de5a31004030938v82d1c243k27be011f9a681f76@mail.gmail.com>
<21301.1270314309@sss.pgh.pa.us>
Hi Tom,
Thank you for your Prompt reply..
Am getting this error only in the application level that too with multiple
sessions. By getting that error am assuming that the table has got dropped
in some other session.
I understood from here is that its not a serious problem to catalog
Corruption.
Regards
Raghavendra
On Sat, Apr 3, 2010 at 10:35 PM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> raghavendra t <raagavendra.rao@gmail.com> writes:
> > I am facing the error "cache lookup failed for relation X" in
> Postgres-8.4.2
> > [ when dropping the same table concurrently in two sessions ]
> > Could plese tell me, why this is generated and what is the cause.
>
> From the perspective of session B, the table disappeared after it had
> already found the table in the catalogs and obtained a lock on it.
> This is not readily distinguishable from a serious problem such as
> catalog corruption. While we could play dumb and just issue a
> "table does not exist" message as though we'd never found it in the
> catalog at all, that behavior could mask real problems, so it seems
> better to not try to hide that something unusual happened.
>
> In general I would say that an application that is trying to do this
> has got its own problems anyway --- how do you know which version of
> the table you're dropping, and that that's the right thing?
>
> regards, tom lane
>
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To: pgsql-performance@postgresql.org
Cc: raagavendra.rao@gmail.com, tgl@sss.pgh.pa.us, pgsql-general@postgresql.org
Subject: Re: ERROR: cache lookup failed for relation X
In-Reply-To: <k2mbc7de5a31004031950pebd99d60t737c2d642b1b99fe@mail.gmail.com>
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