Re: LEFT JOIN ON vs. LEFT JOIN USING performance

From: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
To: "Diego de Lima" <diego(at)sistemica(dot)info>
Cc: pgsql-performance(at)postgresql(dot)org
Subject: Re: LEFT JOIN ON vs. LEFT JOIN USING performance
Date: 2005-08-19 15:40:49
Message-ID: 25396.1124466049@sss.pgh.pa.us
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"Diego de Lima" <diego(at)sistemica(dot)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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