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From:Prasad Budim Ram Date:October 15 2003 9:20am
Subject:Re: Select always "Using FileSort"
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Whenever you use select * MySQL will skip using index. For more
information, http://www.mysql.com/doc/en/MySQL_indexes.html . 

Thanks,
Ram


>>> mos <mos99@stripped> 10/15/2003 10:17:22 AM >>>
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?

TIA

Mike



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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