Re: Database file copy

Alvaro Herrera <alvherre@commandprompt.com>

From: Alvaro Herrera <alvherre@commandprompt.com>
To: Bruce Momjian <bruce@momjian.us>
Cc: Srini Raghavan <sixersrini@yahoo.com>, Robert Haas <robertmhaas@gmail.com>, pgsql-hackers <pgsql-hackers@postgresql.org>
Date: 2011-01-13T20:18:02Z
Lists: pgsql-hackers
Excerpts from Bruce Momjian's message of jue ene 13 00:05:53 -0300 2011:
> Srini Raghavan wrote:
> > Thank you very much for reviewing, appreciate the feedback.? As pointed out by 
> > you, it is always best to test it out with the latest version, so, I tested the 
> > same approach with postgres 9.0.2 on windows just now, and it works! 
> > 
> > 
> > I forgot to mention earlier that in addition to setting vacuum_freeze_table_age 
> > to 0, vacuum_freeze_min_age must also be set to 0 to reset xmin with the 
> > FrozenXid. 
> 
> I wonder if you should be using VACUUM FREEZE instead of having to set
> variables.      

The documentation says you shouldn't:

FREEZE
Selects aggressive "freezing" of tuples. Specifying FREEZE is equivalent to
performing VACUUM with the vacuum_freeze_min_age parameter set to zero. The
FREEZE option is deprecated and will be removed in a future release; set the
parameter instead.
	http://www.postgresql.org/docs/9.0/static/sql-vacuum.html

-- 
Álvaro Herrera <alvherre@commandprompt.com>
The PostgreSQL Company - Command Prompt, Inc.
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