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Re: So what's null then if it's not nothing?

From: Alexandr Savinov <spam_at_conceptoriented.com>
Date: Wed, 23 Nov 2005 12:47:56 +0100
Message-ID: <438456fe$1@news.fhg.de>


Jon Heggland schrieb:
> In article <kfa7o1d714eqdnlfnaik6t1gs6uv4l0b09_at_4ax.com>,
> hugo_at_pe_NO_rFact.in_SPAM_fo says...
>

>>>2- You create a parent/root entity/table and make a subtype for each
>>>optional field
>>
>>And that would lead to an exponential explosion of tables. With one
>>optional attribute, you get two subtypes. Two optional attributes means
>>four subtypes. With 10 optional attributes, you'd need no less than
>>1,024 tables.

>
>
> You mean you would create a table for each *combination* of attributes?
> What on earth for?

In order to avoid nulls (there is an opinion that they need to be removed from schema).

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Received on Wed Nov 23 2005 - 05:47:56 CST

Original text of this message

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