Thread: BUG #15253: DROP/select/update query waiting for pg_dump

BUG #15253: DROP/select/update query waiting for pg_dump

From
PG Bug reporting form
Date:
The following bug has been logged on the website:

Bug reference:      15253
Logged by:          NIRBAN SEN
Email address:      sennirban89@gmail.com
PostgreSQL version: Unsupported/Unknown
Operating system:   rhel7
Description:

DROP/select/update queries are going into waiting state when pg_dump is
running.

I'm using 9.2.18 version.


Re: BUG #15253: DROP/select/update query waiting for pg_dump

From
Andres Freund
Date:
Hi,

On 2018-06-27 14:01:09 +0000, PG Bug reporting form wrote:
> The following bug has been logged on the website:
> 
> Bug reference:      15253
> Logged by:          NIRBAN SEN
> Email address:      sennirban89@gmail.com
> PostgreSQL version: Unsupported/Unknown
> Operating system:   rhel7
> Description:        
> 
> DROP/select/update queries are going into waiting state when pg_dump is
> running.

DROP TABLE, and many other kinds of DDL, are indeed going to be blocked
by a concurrent pg_dump. That's expected and not a bug.  SELECT / UPDATE
on their own won't.

Please note that the form you used is for reporting a bug, but I do not
see one in your report?

Greetings,

Andres Freund


Re: BUG #15253: DROP/select/update query waiting for pg_dump

From
Jeff Janes
Date:
On Wed, Jun 27, 2018 at 10:01 AM, PG Bug reporting form <noreply@postgresql.org> wrote:
The following bug has been logged on the website:

Bug reference:      15253
Logged by:          NIRBAN SEN
Email address:      sennirban89@gmail.com
PostgreSQL version: Unsupported/Unknown
Operating system:   rhel7
Description:       

DROP/select/update queries are going into waiting state when pg_dump is
running.

I'm using 9.2.18 version.


That's not a bug.  Selects and Updates alone should not block on a pg_dump, but in conjunction with DROP they certainly can.  You can't DROP a table while it is being dumped, and you can't select from a table while it is waiting to be dropped.

Cheers,

Jeff