Re: Why database is corrupted after re-booting

From: "Andrus" <eetasoft(at)online(dot)ee>
To: pgsql-general(at)postgresql(dot)org
Subject: Re: Why database is corrupted after re-booting
Date: 2005-10-27 13:51:59
Message-ID: djqm2g$1epl$1@news.hub.org
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>> If I turn power off by breaking power cord when Postgres server is busy,
>> is it possible that
>> after that SELECT * FROM anytable does not work ?
>
> It is always *possible*, but if your system isn't caching writes then it
> is *very very* unlikely. The tricky bit is that a lot of IDE drives don't
> really disable the write-cache.
>
> You should really test properly, but a quick way to know is to run a
> series of single inserts, each in their own transaction. If you get more
> transactions than the speed (rpm) of the disk then you know it *must* be
> caching.

Richard,

thank you.

QUANTUM FIREPALLP LM20.5 is a widely used ATA IDE drive.

Where do find information does it implement write caching properly or not ?

Is there IDE drive compatibility list for Postgres ?

If this information is not available is there a standard utility which can
determine this drive compatibility with Postgres under Windows ?

Is it possible write utility which converts corrupted database to readable
state so that SELECT * FROM anytable will work always ?
This utility may remove all contraints, just create database which contains
as much data as possible.
Then I can import this data to empty correct database and discard all rows
which violate database rules.

Andrus.

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