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Re: Use of DISTINCT in INNER JOIN
Posted by: Steve Croall
Date: March 28, 2009 02:02AM

Ok, thanks. We will just have to be careful anywhere we use DISTINCT and JOINs.

I still don't know why it has to do a full table scan in order to process the DISTINCT on the two columns. Surely it has only to go through the result set generated by the JOIN.

Is it because the use of the DISTINCT clause causes the ON clause not to use the available index? Without DISTINCT the index is used.

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Use of DISTINCT in INNER JOIN
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Steve Croall
March 24, 2009 12:07PM
Re: Use of DISTINCT in INNER JOIN
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Steve Croall
March 24, 2009 02:00PM
Re: Use of DISTINCT in INNER JOIN
6981
Rick James
March 25, 2009 07:01PM
Re: Use of DISTINCT in INNER JOIN
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Steve Croall
March 27, 2009 05:20AM
Re: Use of DISTINCT in INNER JOIN
5915
Rick James
March 27, 2009 10:01AM
Re: Use of DISTINCT in INNER JOIN
6868
Steve Croall
March 28, 2009 02:02AM
Re: Use of DISTINCT in INNER JOIN
4738
Rick James
March 28, 2009 03:53PM
Re: Use of DISTINCT in INNER JOIN
5944
Steve Croall
April 01, 2009 03:36AM
Re: Use of DISTINCT in INNER JOIN
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Rick James
April 02, 2009 12:16AM
Re: Use of DISTINCT in INNER JOIN
5692
Steve Croall
April 02, 2009 06:29AM


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