Re: Table partition: question

From: Jonathan Lewis <jonathan_at_jlcomp.demon.co.uk>
Date: Tue, 20 Jul 2004 13:57:18 +0000 (UTC)
Message-ID: <cdj8bu$fsd$1@titan.btinternet.com>

It is not possible to do what you want, and the approach of concatenating bits of string into a single field is not a good idea.

However, you can get quite close to your requirement by adding an extra column to your table, and populating it with a before insert/update row trigger that extracts the character from the longer string.

You can then partition on the single character column.

Bear in mind that this will turn array handling code into single-row processing, and add a significant overhead to jobs like bulk-loading.

-- 
Regards

Jonathan Lewis

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"darkeagle" <NOSPAM_at_italy.it> wrote in message
news:2m22nuFhu2eoU1_at_uni-berlin.de...


> > PARTITION BY HASH ({column_name}) would only accept, well, a column

> > name. Hash partitioning is mostly used in order to achieve even

> > distribution of your data. Would be interesting to know what you're

> > trying to do.

> In my case, the field Info VarChar(8) hold a concatenation of moer

> information.

> I would create a hash partition based, for example, only on third

character


> of this field.

> You think this is possible?

> Thank you.

>

>

Received on Tue Jul 20 2004 - 08:57:18 CDT