apache/spark — pull request #3362 by wangxiaojing (2014-11-19 10:21:30+00:00)
Title: [SPARK-4485][SQL]Add BroadcastHashOuterJoin

We are planning to create a {{BroadcastHashouterJoin}} to implement the broadcast join for {{left outer join}} and {{right outer join}}

We use {{left outer join}} for example:
if the size of data from right side is smaller than the user-settable threshold [[AUTO_BROADCASTJOIN_THRESHOLD]]
then we make the right side data as a broadcast
and implement the join opration reference to {{HashOuterJoin}} and {{BroadcastHashJoin}}
else
we still use {{HashOuterJoin}}

The testsuite is writing.