Horton

Re: pg_dump versus hash partitioning

Tom Lane <tgl@sss.pgh.pa.us>

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From: Tom Lane <tgl@sss.pgh.pa.us>
To: Julien Rouhaud <rjuju123@gmail.com>
Cc: Andrew Dunstan <andrew@dunslane.net>, Alvaro Herrera <alvherre@alvh.no-ip.org>, David Rowley <dgrowleyml@gmail.com>, Peter Geoghegan <pg@bowt.ie>, Robert Haas <robertmhaas@gmail.com>, pgsql-hackers@lists.postgresql.org, Andrew <pgsqlhackers@andrewrepp.com>
Date: 2023-03-11T03:10:14Z
Lists: pgsql-hackers 
Julien Rouhaud <rjuju123@gmail.com> writes:
> Working on some side project that can cause dump of hash partitions to be
> routed to a different partition, I realized that --load-via-partition-root can
> indeed cause deadlock in such case without FK dependency or anything else.

> The problem is that each worker will perform a TRUNCATE TABLE ONLY followed by
> a copy of the original partition's data in a transaction, and that obviously
> will lead to deadlock if the original and locked partition and the restored
> partition are different.

Oh, interesting.  I wonder if we can rearrange things to avoid that.

			regards, tom lane

Commits

  1. Simplify and speed up pg_dump's creation of parent-table links.

  2. Fix pg_dump for hash partitioning on enum columns.