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To: "'Kevin Grittner'" <Kevin.Grittner@wicourts.gov>, "'Richard Huxton'"
	<dev@archonet.com>, "'Sergey Konoplev'" <gray.ru@gmail.com>, "Anibal David
	Acosta" <aa@devshock.com>
Cc: pgsql-performance@postgresql.org, "'Stephen Frost'" <sfrost@snowman.net>
Subject: Re: unlogged tables
References: <005501cca0ad$b9478440$2bd68cc0$@devshock.com>
	<20111111201822.GN24234@tamriel.snowman.net>
	<CAL_0b1t02q77ft2JWdjMv8q4vaGm=x__K0rzVkpNSvSy2-SjzA@mail.gmail.com>
	<4EC0D827.8090601@archonet.com>
	<CAL_0b1tuxi9YVhGKsNUSTZCUBXgOmppan7w+KkRZARbQ=u4P5w@mail.gmail.com>
	<4EC0EAD6.9010302@archonet.com>
	<CAL_0b1sSyTgMUxcRi+2ibTHHV4-qH3fvacsQUCbbeBsu0jYGAQ@mail.gmail.com>
	<00ea01cca2ef$abcf3a30$036dae90$@devshock.com>
	<4EC0FAE80200002500042E6C@gw.wicourts.gov>
	<00ff01cca2f4$3cb86860$b6293920$@devshock.com>
Date: Sun, 04 Dec 2011 13:28:03 +0100
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From: "Pierre C" <lists@peufeu.com>
Message-ID: <op.v5ysw1d3eorkce@apollo13>
In-Reply-To: <00ff01cca2f4$3cb86860$b6293920$@devshock.com>
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> My table is a statistics counters table, so I can live with a partial =20
> data
> loss, but not with a full data loss because many counters are weekly an=
d
> monthly.
>
> Unlogged table can increase speed, this table has about 1.6 millions of
> update per hour, but unlogged with a chance of loss all information on =
a
> crash are not a good idea for this.

You could use an unlogged table for hourly updates, and periodically, =20
accumulate those counters to a (logged) daily/weekly table...

The hourly table could be rebuilt by examining only 1 hour's worth of =20
data, so it isn't too much of a problem if it's lost. The other tables =20
would get much less updates.