Re: Using an import as a defrag

From: Frank van Bortel <>
Date: Thu, 24 Jan 2008 20:48:49 +0100
Message-ID: <5d448$4798eba1$524b5c40$>

Juha Laiho wrote:

> bdbafh <> said:

>> On Jan 22, 12:38 pm, howard <> wrote:
>>> I was talking with fellow DBA that told me that I should export my
>>> schema, drop it, and re-import it.

>> What performance problems is the application currently experiencing?
>> Is the database growth causing a problem, such as backups failing to
>> complete during their maintenance window?
> These (above) are the proper questions to ask. If it's working ok
> (and there's nothing to indicate that it is degrading in some way),
> don't waste your time.

>> The paper by Juan Loiza entitled "how to stop defragmenting and start
>> living" isn't returned in a search via google. That paper was
>> typically a good start.

It was, in the pre 8.0 days - and when you still are on that version, your DBA *might* have a point. For now, I'll reckon it's Compulsive Tuning Disorder, a rare disease, some elder DBA's suffered from.
CTD can be cured by LMT (Locally Managed Tablespaces), that will kill the "no more than 1024 extents" myth as a nice side effect.

Rollback segments and OPTIMAL - yeach!

Please, do *not* read that paper (other than for anecdotal, or historical reasons)


Frank van Bortel

Top-posting in UseNet newsgroups is one way to shut me up
Received on Thu Jan 24 2008 - 13:48:49 CST

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