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Re: Normalization, Natural Keys, Surrogate Keys

From: Galen Boyer <galendboyer_at_yahoo.com>
Date: 21 May 2002 21:54:11 -0500
Message-ID: <uptzou3j6.fsf@rcn.com>


On 21 May 2002, ed.prochak_at_alltel.com wrote:
> Galen Boyer <galendboyer_at_yahoo.com> wrote in message

>> Performance should be increased on joins with tables each having one
>> surrogate key over tables all having natural keys and most of these
>> having multiple values.

>
> Galen,
> I'm not sure what you really meant here but:

[...]

> (now there is a factor of the size of the keys, so a table with MANY
> rows will be slower for the natural key because fewer of them fit in a
> block, so more blocks must be read to find it. but if this amounted to
> something even near a factor of two, I'd be supprised.)

This is what I meant. Scan performance are all about the amount of blocks being read, index or table.

-- 
Galen deForest Boyer
Sweet dreams and flying machines in pieces on the ground.
Received on Tue May 21 2002 - 21:54:11 CDT

Original text of this message

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