From: Tom Lane <tgl@sss.pgh.pa.us>
To: Diego de Lima <diego@sistemica.info>
Cc: pgsql-performance@postgresql.org
Subject: Re: LEFT JOIN ON vs. LEFT JOIN USING performance
Date: Fri, 19 Aug 2005 11:40:49 -0400
Message-ID: <25396.1124466049@sss.pgh.pa.us> (raw)
In-Reply-To: <002a01c5a4d1$d36f6420$3dc8a8c0@diretoria02>
References: <002a01c5a4d1$d36f6420$3dc8a8c0@diretoria02>
"Diego de Lima" <diego@sistemica.info> writes:
> I have some very complex select statements on 4 million rows tables. =
> When using LEFT JOIN ON, some select statements takes about 2 minutes. =
> When I write exactly the same statement but with LEFT JOIN USING, it =
> takes only 1 minute.
Could we see details please? Like the table schemas, the query itself,
and EXPLAIN ANALYZE results for both cases.
regards, tom lane
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To: pgsql-performance@postgresql.org
Cc: tgl@sss.pgh.pa.us, diego@sistemica.info
Subject: Re: LEFT JOIN ON vs. LEFT JOIN USING performance
In-Reply-To: <25396.1124466049@sss.pgh.pa.us>
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