Re: Why is the query not using the index for sorting?

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От Matthew Wakeling
Тема Re: Why is the query not using the index for sorting?
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Msg-id alpine.DEB.2.00.0911231058560.684@aragorn.flymine.org
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Ответ на Why is the query not using the index for sorting?  (Jonathan Blitz <jblitz@013.net>)
Ответы Re: Why is the query not using the index for sorting?  (Jonathan Blitz <jblitz@013.net>)
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On Sun, 22 Nov 2009, Jonathan Blitz wrote:
> I have a table with a number of columns.
>  
> I perform
>  
> Select *
> from table
> order by a,b
>  
> There is an index on a,b which is clustered (as well as indexes on a and b alone).
> I have issued the cluster and anyalze commands.

Did you analyse *after* creating the index and clustering, or before?

Matthew

--
 [About NP-completeness] These are the problems that make efficient use of
 the Fairy Godmother.                    -- Computer Science Lecturer

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