Re: BUG #7809: Running pg_dump on slave w/ streaming replication fails if there are unlogged tables

On Tue, Jan 15, 2013 at 12:13 AM, <joe(at)tanga(dot)com> wrote:
> The following bug has been logged on the website:
>
> Bug reference: 7809
> Logged by: Joe Van Dyk
> Email address: joe(at)tanga(dot)com
> PostgreSQL version: 9.2.2
> Operating system: Ubuntu
> Description:
>
> Running pg_dump on a streaming replication slave with a database that has
> unlogged_tables will fail unless you provide the "--no-unlogged-table-data"
> option with the following (scary) error:
>
> pg_dump: Dumping the contents of table "tracking_import_data" failed:
> PQgetResult() failed.
> pg_dump: Error message from server: ERROR: could not open file
> "base/16388/190326": No such file or directory
> pg_dump: The command was: COPY public.tracking_import_data (uuid,
> tracking_number) TO stdout;
>
> (this guy encountered the error as well:
> http://www.postgresql.org/message-id/DE2DE764-307D-4A23-A9A9-6608AC0977CB@ticketevolution.com
> )
>
> Could running pg_dump against a slave always use the
> "--no-unlogged-table-data" option?

That sounds like a pretty reasonable idea, I think. Should be easy
enough to figure out at an early stage, too.

That said, it wouldn't hurt if we could make that error a little less
scary. Instead of saying "could not open file", could we find a way to
say "this is an unlogged table on a slave, it's not going to work"?

We can fix pg_dump the easy way, but what about custom tools...

--
Magnus Hagander
Me: http://www.hagander.net/
Work: http://www.redpill-linpro.com/