From: Martijn Tonies
Date: January 29 2010 10:10pm
Subject: Re: 50 things to know before migrating from Oracle to MySQL
List-Archive: http://lists.mysql.com/mysql/220483
Message-Id: <006201caa12f$dd73d050$6101a8c0@martijnws>
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>> as a relatively unsophisticated dbms user (just dynamic web site back 
>> end),
>> i thought it was very interesting to see the kinds of things oracle users 
>> do
>> that i'd never have imagined.
>>
>> more than 61 joins in a query?! man, those guys are hardcore.
>>
>>
>
> Hardcore stupid if you ask me.  I suppose it is "possible" to have a valid 
> reason (can't imagine what it might be) for using more than 61 joins.  But 
> I would be willing to bet that 99.99% of the time if you get even close to 
> that many joins you have a very poorly designed database.  I would also 
> bet that 80% of the people who are actually writing queries with that many 
> joins don't have a solid grasp of the fundamental principles of relational 
> database design.

Why not? Normalizing gets you -more- tables, not less.

That being said, try joining several complex views and you'll get more
joins...


With regards,

Martijn Tonies
Upscene Productions
http://www.upscene.com

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