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From: Tom Lane <tgl@sss.pgh.pa.us>
To: Kevin Grittner <kgrittn@ymail.com>
cc: Andrew Dunstan <andrew@dunslane.net>,
 Vlad Arkhipov <arhipov@dc.baikal.ru>,
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Subject: Re: Postgres does not use indexes with OR-conditions
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Comments: In-reply-to Kevin Grittner <kgrittn@ymail.com>
 message dated "Fri, 07 Nov 2014 06:17:31 -0800"
Date: Fri, 07 Nov 2014 10:11:48 -0500
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Kevin Grittner <kgrittn@ymail.com> writes:
> On the other hand, why not simply write it as?:

> select *
>   from commons.financial_documents fd
>   where (fd.creation_time, fd.financial_document_id)
>       < ('2011-11-07 10:39:07.285022+08', 100)
>   order by fd.creation_time desc
>   limit 200

That's the way to do it, not only because it's simpler and clearer,
but because the planner will recognize the relevance of the
condition to an index on creation_time, financial_document_id ...

			regards, tom lane


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