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Re: LEFT JOIN ON vs. LEFT JOIN USING performance - Mailing list pgsql-performance

From Tom Lane
Subject Re: LEFT JOIN ON vs. LEFT JOIN USING performance
Date
Msg-id 25396.1124466049@sss.pgh.pa.us
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In response to LEFT JOIN ON vs. LEFT JOIN USING performance  ("Diego de Lima" <diego@sistemica.info>)
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"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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