Re: EXISTS Keyword - Mailing list pgsql-sql

From Bruce Momjian
Subject Re: EXISTS Keyword
Date
Msg-id 200110040159.f941xio07679@candle.pha.pa.us
Whole thread Raw
In response to EXISTS Keyword  (<cnliou@eurosport.com>)
List pgsql-sql
> Hello!
> 
> I vaguely remember that someone said somewhere that
> EXISTS runs faster than IN:
> 
> SELECT * FROM table1 where field1 EXISTS (SELECT
> field4 FROM table2)

Move field1 into the subquery and join it to table2.  See the FAQ for an
example.

--  Bruce Momjian                        |  http://candle.pha.pa.us pgman@candle.pha.pa.us               |  (610)
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