Re: pg_dump and dependencies and --section ... it's a mess

Andrew Dunstan <andrew@dunslane.net> writes:
> On 06/21/2012 07:43 PM, Tom Lane wrote:
>> I didn't understand that then, and I still don't.

> If something else holds a lock on the table (e.g. another CREATE INDEX) 
> the ALTER TABLE will block until it's done, waiting for an ACCESS 
> EXCLUSIVE lock. The whole method of operation of parallel restore is 
> that we are not supposed to start items that might be blocked by 
> currently running operations.

Oh, I see --- Andrew Hammond's complaint involves *three* index
creations on the same table (one running; a second one completed except
for the ALTER TABLE CLUSTER step attached to it, which is blocked behind
the running index creation; and a third blocked behind the ALTER TABLE
CLUSTER).  I had misread it to imply that only two indexes were enough
to manifest the problem.

Yeah, we should break out the ALTER TABLE CLUSTER step as a separate
TOC item to fix this.
        regards, tom lane