From: walter harms
Date: September 12 2008 7:38am
Subject: Re: performance question
List-Archive: http://lists.mysql.com/mysql/214450
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you mail like to find it by your self. simply use : explain <query>

re,
  wh

Yong Lee schrieb:
> All,
>  
> Just curious as to which query would be better in terms of performance:
>  
> select * from (select * from a union select * from b) as c;
>  
> versus
>  
> select * from a union select * from b;
>  
> or would these 2 queries be the same ?
>  
> Thanks,
> Yong.
>  
> 
> Yong Lee
> 
> Developer
> 
> ylee@stripped
> 
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