From: Martijn Tonies
Date: April 17 2007 2:13pm
Subject: Re: Max columns in a tabel in MyISAM storage engine
List-Archive: http://lists.mysql.com/mysql/206216
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> Not necessarily. I do precisely this for a data base whose structure I do
> not control. I stuff
>
> |code1|code2|code3| ...
>
> Into an unused text field. The users can query on LIKE "%|code2|%. The key
> is to have a delimiter at the start and end of the entire list, so that
the
> string match doesn't get confused.
>
> Of course, this would probably be painfully slow. I can't say whether or
not
> it would be slower than the other alternatives.

It is slow, because it cannot use an index.

All in all, bad design IMO, cause you _know_ it's slow beforehand.

Martijn Tonies
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