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From: "Bath, David" <dave.bath@unix.net>
Reply-To: dave.bath@unix.net
To: pgsql-sql@postgresql.org
Subject: Re: why vacuum
Date: Wed, 26 Oct 2005 16:22:40 +1000
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On Wed, 26 Oct 2005 15:14, Tom Lane wrote:
  > Kenneth Gonsalves <lawgon@thenilgiris.com> writes:
  > > (A MySQueeeel guy said, not Kenneth)...
  > > 'I wouldnt commit mission critical data to a database that needs to be 
  > > vacuumed once a week'.
My two-penneth worth...<flamage>
I wouldn't commit mission critical data to a database (or DBA) that doesn't
have a concept of vacuuming (or desire to do it regularly).  But, less
flamingly, I wouldn't commit mission-critical data to something that lacked
the ability to have proper constraints, triggers and server-side procedures
to ensure the data actually remains sensible.  Note that Sybase/MS-SQL's
check constraint model asserts the constraint BEFORE the trigger, which
discourages you from attempting to check and handle meaning of data!</flamage>

  > This guy is not worth arguing with.
D'Accord!

  > > So why does pg need vacuum?
For (inter alia) the same reason that
* Oracle has an ANALYZE_SCHEMA and DBMS_SPACE_ADMIN
and (hoist by his own petard)
* MySQueeeeaL has myisamchk --stats_method=method_name --analyze

<flamage>Oh, well: MySQL bigot and internal consistency? whadya expect?</flamage>
 
Dave Bath
(Oracle DBA for health/telcos way back in 1986: honeywrong GCOS and Pr1mos)
-- 
David T. Bath
dave.bath@unix.net