Horton

Re: [HACKERS] [BUGS] BUG #14825: enum type: unsafe use?

Robert Haas <robertmhaas@gmail.com>

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From: Robert Haas <robertmhaas@gmail.com>
To: Thomas Munro <thomas.munro@enterprisedb.com>
Cc: Andres Freund <andres@anarazel.de>, Andrew Dunstan <andrew.dunstan@2ndquadrant.com>, Tom Lane <tgl@sss.pgh.pa.us>, Stephen Frost <sfrost@snowman.net>, Bruce Momjian <bruce@momjian.us>, "David E. Wheeler" <david@justatheory.com>, Christophe Pettus <christophe.pettus@pgexperts.com>, Postgres-Bugs <pgsql-bugs@postgresql.org>, "pgsql-hackers@postgresql.org" <pgsql-hackers@postgresql.org>
Date: 2018-01-12T12:51:34Z
Lists: pgsql-bugs, pgsql-hackers 
On Thu, Jan 11, 2018 at 11:01 PM, Thomas Munro
<thomas.munro@enterprisedb.com> wrote:
> Are you saying we should do the work now to create a per-transaction
> DSM segment + DSA area + thing that every backend attaches to?

No, I was just thinking you could stuff it into the per-parallel-query
DSM/DSA.  But...

> I didn't think creating backend local hash tables would be a problem
> because it's a vanishingly rare occurrence for the hash table to be
> created at all (ie when you've altered an enum), and if created, to
> have more than a couple of entries in it.

...this is also a fair point.

-- 
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company

Commits

  1. Revert to 9.6 treatment of ALTER TYPE enumtype ADD VALUE.

  2. Remove heuristic same-transaction test from check_safe_enum_use().

  3. Use a blacklist to distinguish original from add-on enum values.

  4. Add support for coordinating record typmods among parallel workers.