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Re: plan variations: join vs. exists vs. row comparison - Mailing list pgsql-performance

From Kevin Grittner
Subject Re: plan variations: join vs. exists vs. row comparison
Date
Msg-id 4D74EAA4020000250003B5AB@gw.wicourts.gov
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In response to Re: plan variations: join vs. exists vs. row comparison  (Jon Nelson <jnelson+pgsql@jamponi.net>)
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Jon Nelson <jnelson+pgsql@jamponi.net> wrote:

> What is the difference between a plain join and a semi join?

As soon as a semi join finds a match it stops looking for more.

-Kevin

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