Thread: pqReadData() - backend unexpectedly closed the channel

pqReadData() - backend unexpectedly closed the channel

From
"Scott Price"
Date:
To:  Tom Lane, and Postgresql.org staff,

This is a message in response to the one sent by Frank Miles on Tue 7 Nov 2000 11:11:29 -0800 (PST).

I have been experiencing the same problem as the gentleman, Frank Miles, when running Postgre SQL.  I have been
repeatedlygetting "pqReadData - backend closed the channel unexpectedly.  This probably means that .... the backend
abruptlyterminated before or while your request was being processed" (or something close to those words).  The last
responseI saw from postgresql.org to Frank was from a fellow Tom Lane asking to see a core dump.  Since I experienced
thisproblem I would like to send you a core dump of my file (which is gzipped), core.gz, and if you all could give me
anyexplanations or recommendations, I'd appreciate it. 

Postgre SQL Version 6.5.3 on i686-pc-linux-gnu, compiled by gcc egcs-2.91.66.

My email:  scott.price@sci.com


Thanks,


Scott M. Price


Attachment

Re: pqReadData() - backend unexpectedly closed the channel

From
Tom Lane
Date:
"Scott Price" <Scott.Price@sci.com> writes:
> The last response I saw =
> from postgresql.org to Frank was from a fellow Tom Lane asking to see a =
> core dump.  Since I experienced this problem I would like to send you a =
> core dump of my file (which is gzipped), core.gz

No, I wanted to see a backtrace.  A core dump is of no value on any
other platform than your own, especially without a copy of the same
executable you used (and no, don't send that).

            regards, tom lane

(Marc, why in the world did you approve a 280k binary posting to
pgsql-general?  There are going to be a lot of annoyed people...)

Re: pqReadData() - backend unexpectedly closed the channel

From
"Rob Arnold"
Date:
I can make this happen consistently with Perl DBI by placing a
$dbh->disconnect() in the DESTROY subroutine of an object.  I doubt the two
issues have much in common, but there's my $.02.  You might post to the list
(not me, I'm ignorant) how you managed to make this happen.

--rob

----- Original Message -----
From: "Scott Price" <Scott.Price@sci.com>
To: <pgsql-general@postgresql.org>; "<Tom Lane" <tgl@sss.pgh.pa.us>
Sent: Monday, March 12, 2001 7:56 PM
Subject: pqReadData() - backend unexpectedly closed the channel


To:  Tom Lane, and Postgresql.org staff,

This is a message in response to the one sent by Frank Miles on Tue 7 Nov
2000 11:11:29 -0800 (PST).

I have been experiencing the same problem as the gentleman, Frank Miles,
when running Postgre SQL.  I have been repeatedly getting "pqReadData -
backend closed the channel unexpectedly.  This probably means that .... the
backend abruptly terminated before or while your request was being
processed" (or something close to those words).  The last response I saw
from postgresql.org to Frank was from a fellow Tom Lane asking to see a core
dump.  Since I experienced this problem I would like to send you a core dump
of my file (which is gzipped), core.gz, and if you all could give me any
explanations or recommendations, I'd appreciate it.

Postgre SQL Version 6.5.3 on i686-pc-linux-gnu, compiled by gcc
egcs-2.91.66.

My email:  scott.price@sci.com


Thanks,


Scott M. Price




Re: Re: pqReadData() - backend unexpectedly closed the channel

From
Dirk Lutzebaeck
Date:
Rob Arnold writes:
 > I can make this happen consistently with Perl DBI by placing a
 > $dbh->disconnect() in the DESTROY subroutine of an object.  I doubt the two
 > issues have much in common, but there's my $.02.  You might post to the list
 > (not me, I'm ignorant) how you managed to make this happen.

Yes, the same here. You must not does this as the described in DBI
manpage (last sentence):

           The database is automatically disconnected (by the
           DESTROY method) if still connected when there are no
           longer any references to the handle.  The DESTROY
           method for each driver should implicitly call rollback
           to undo any uncommitted changes. This is vital
           behaviour to ensure that incomplete transactions don't
           get committed simply because Perl calls DESTROY on
           every object before exiting. Also, do not rely on the
           order of object destruction during 'global
           destruction', it is undefined.

Dirk

Re: pqReadData() - backend unexpectedly closed the channel

From
Frank Miles
Date:
On Mon, 12 Mar 2001, Scott Price wrote:

> To:  Tom Lane, and Postgresql.org staff,
>
> This is a message in response to the one sent by Frank Miles on Tue 7 Nov 2000 11:11:29 -0800 (PST).
>
> I have been experiencing the same problem as the gentleman, Frank Miles, when running Postgre SQL.  I have been
repeatedlygetting "pqReadData - backend closed the channel unexpectedly.  This probably means that .... the backend
abruptlyterminated before or while your request was being processed" (or something close to those words).  The last
responseI saw from postgresql.org to Frank was from a fellow Tom Lane asking to see a core dump.  Since I experienced
thisproblem I would like to send you a core dump of my file (which is gzipped), core.gz, and if you all could give me
anyexplanations or recommendations, I'd appreciate it. 
>
> Postgre SQL Version 6.5.3 on i686-pc-linux-gnu, compiled by gcc egcs-2.91.66.
>
> My email:  scott.price@sci.com

My dim recollection was that the underlying problem was that a table had been renamed
(bad order of operations!!), damaging one or more foreign key links.  I was able to
fix it by editing a pg_dump'ed version of the database, and restoring the database
from the dump, thereby repairing the FK links.

Your problem may be different!

    -frank