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Re: Unnecessary repeat condition for a self inner join - Mailing list pgsql-sql

From Tom Lane
Subject Re: Unnecessary repeat condition for a self inner join
Date
Msg-id 14041.1215876025@sss.pgh.pa.us
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In response to Re: Unnecessary repeat condition for a self inner join  ("Robins Tharakan" <tharakan@gmail.com>)
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"Robins Tharakan" <tharakan@gmail.com> writes:
> Besides, I did a simple test and although you are right about the optimizer
> deducing implied equality conditions, this holds true only for a direct
> join. In the second query, the optimizer recommends a table scan even for a
> simple IN() condition.

An IN is not an equivalence condition.
        regards, tom lane

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