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left join where not null vs. inner join - Mailing list pgsql-sql

From	Emi Lu
Subject	left join where not null vs. inner join
Date	May 22, 2009 20:52:04
Msg-id	4A17106F.7040302@encs.concordia.ca Whole thread Raw
Responses	Re: left join where not null vs. inner join (Erik Jones <ejones@engineyard.com>)
List	pgsql-sql

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Two tables, each contains more than hundreds of thousands records. Is 
there any efficiency differences between (1) and (2)?

(1) T1 inner join T2 using (c1, c2)


(2) T1 left join T2 using (c1, c2) where c2 is not null


Thanks,
--
Lu Ying

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From: Tom Lane
Date: 22 May 2009, 18:34:36
Subject: Re: help with pg_hba.conf

From: Erik Jones
Date: 22 May 2009, 21:05:37
Subject: Re: left join where not null vs. inner join

left join where not null vs. inner join - Mailing list pgsql-sql

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