Hadoop's Map-side join implements Hash join?

Posted by ge0rgi0 on Stack Overflow See other posts from Stack Overflow or by ge0rgi0
Published on 2010-05-12T22:47:18Z Indexed on 2010/06/03 3:24 UTC
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join

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hash

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hadoop

I try to implement Hash join in Hadoop.

However, Hadoop seems to have already a map-side join and a reduce - side join already implemented.

What is the difference between these techniques and hash join?

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