Re: pg_dump bug in 9.4beta2 and HEAD

Heikki Linnakangas wrote:
> On 08/14/2014 06:53 AM, Joachim Wieland wrote:
> >I'm seeing an assertion failure with "pg_dump -c --if-exists" which is
> >not ready to handle BLOBs it seems:
> >
> >pg_dump: pg_backup_archiver.c:472: RestoreArchive: Assertion `mark !=
> >((void *)0)' failed.
> >
> >To reproduce:
> >
> >$ createdb test
> >$ pg_dump -c --if-exists test  (works, dumps empty database)
> >$ psql test -c "select lo_create(1);"
> >$ pg_dump -c --if-exists test  (fails, with the above mentioned assertion)
> 
> The code tries to inject an "IF EXISTS" into the already-construct
> DROP command, but it doesn't work for large objects, because the
> deletion command looks like "SELECT pg_catalog.lo_unlink(xxx)".
> There is no DROP there.

Ah, so this was broken by 9067310cc5dd590e36c2c3219dbf3961d7c9f8cb.
Pavel, any thoughts here?  Can you provide a fix?

We already have a couple of object-type-specific checks in there, so I
think it's okay to add one more exception for large objects.

-- 
Álvaro Herrera                http://www.2ndQuadrant.com/
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