Re: ALTER TABLE lock strength reduction patch is unsafe

Alvaro Herrera <alvherre@commandprompt.com>

From: Alvaro Herrera <alvherre@commandprompt.com>
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: Robert Haas <robertmhaas@gmail.com>, Simon Riggs <simon@2ndquadrant.com>, pgsql-hackers <pgsql-hackers@postgresql.org>
Date: 2011-06-21T18:24:31Z
Lists: pgsql-hackers

Commits

Same data as JSON: GET /api/v1/messages/:b64id/commits the thread's linked commits as JSON, with link sources. API reference →
  1. Add bytea_agg, parallel to string_agg.

  2. Fix ALTER TABLE ONLY .. DROP CONSTRAINT.

Excerpts from Tom Lane's message of mar jun 21 11:06:22 -0400 2011:

> Please note that this position should not be regarded as support for
> Simon's proposed patch.  I still think the right decision is to revert
> the ALTER TABLE feature, mainly because I do not believe this is the
> last bug in it.  And the fact that there's a pre-existing bug with a
> vaguely similar symptom is no justification for introducing more bugs.

Note that this feature can be disabled by tweaking
AlterTableGetLockLevel so that it always returns AccessExclusive.

-- 
Álvaro Herrera <alvherre@commandprompt.com>
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