concatenated indexes deliver faster results as concatenated indexes do not require the resultsets to be merged
provided the more selective column of the concatenated index is first and least selective column of the concatenated index is last
http://webglobalnet.net/support/index.php?topic=864.0
HTH
Martin Gainty
“I shall take all the troubles of the past, all the disappointments, all the headaches, and I shall pack them in a bag and toss them in the East River.” - Trygve Lie______________________________________________
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> Date: Thu, 22 Apr 2010 23:36:51 +0200
> From: btj@havleik.no
> To: pgsql-general@postgresql.org
> Subject: [GENERAL] Creating indexes?
>
> What is the best approach for PostgreSQL when creating indexes? E.g I have two fields in a table that I want indexed, is it best to create one index
> combining the two fields or creating one for each field? If I create one for each field, will the search when using both fields be slower that a
> combined index?
>
>
> Regards,
>
> BTJ
>
> --
> -----------------------------------------------------------------------------------------------
> Bjørn T Johansen
>
> btj@havleik.no
> -----------------------------------------------------------------------------------------------
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