hash-join

I would like to know what exactly is a hash join or where can I read
about this.
Thanks in advance
sorry for sending to two different groups(I don?t know where to fit this
question)

See my Internals Presentation at the bottom of the developers web site:

http://developers.postgresql.org

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  Bruce Momjian                        |  http://candle.pha.pa.us
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