Date: Wed, 13 Nov 2013 10:16:32 -0500
From: Bruce Momjian <bruce@momjian.us>
To: David Johnston <polobo@yahoo.com>
Cc: PostgreSQL-development <pgsql-hackers@postgreSQL.org>
Subject: Idea for debug/recovery snapshots
Message-ID: <20131113151632.GD24549@momjian.us>
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On Tue, Nov 12, 2013 at 08:39:35PM -0500, Bruce Momjian wrote:
> > My specific wording is incoherent mostly because it really belongs to a
> > larger corpus that currently exists only in my head.
> 
> Oh, OK, it sounds fine.  The user really doesn't choose what timeline to
> see --- rather, it is the current xid at the time they take their
> snapshot and other running xids that controls that.  You can control
> your transaction isolation level, but that only controls how often you
> take snapshots.

[ moved to hackers ]

Actually, it would be possible to allow snapshots that are equal to the
earliest active snapshot for the current database.  I don't think it
would be useful in production, but perhaps for debugging or some
disaster recovery.

-- 
  Bruce Momjian  <bruce@momjian.us>        http://momjian.us
  EnterpriseDB                             http://enterprisedb.com

  + Everyone has their own god. +


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