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From:Egor Egorov Date:October 15 2003 12:47pm
Subject:Re: Select always "Using FileSort"
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mos <mos99@stripped> wrote:
> I want to speed up a large query and I noticed if I do an:
> 
> Explain select * from LargeTable order by IndexCol1
> 
> it always has Extra "Using FileSort", which means it is physically sorting 
> the result set.
> I've tried different tables and sorted on different index columns, and it 
> is always using FileSort.
> 
> How do I get MySQL 4.1.0 to use an index when sorting a MyISAM table?
> Or is Explain broken and does it always report it is using FileSort?

Look at the last paragraph of the following section in the manual:
	http://www.mysql.com/doc/en/MySQL_indexes.html



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Thread
Select always "Using FileSort"mos15 Oct
  • Re: Select always "Using FileSort"Egor Egorov15 Oct
    • Re: Select always "Using FileSort"mos15 Oct
      • Re: Select always "Using FileSort"Dan Nelson15 Oct
Re: Select always "Using FileSort"Prasad Budim Ram15 Oct
Re: Select always "Using FileSort"mos16 Oct