问题描述
我有火花工作.我正在使用Cassandra作为数据存储.我有需要与cassandra表一起加入的流.我正在使用spark-cassandra-connector，有一个很棒的方法 joinWithCassandraTable ，据我所知，用cassandra表实现内部联接
I have spark streaming job. I am using Cassandra as datastore.I have stream which is need to be joined with cassandra table.I am using spark-cassandra-connector, there is great method joinWithCassandraTable which is as far as I can understand implementing inner join with cassandra table
val source: DStream[...] = ...
source.foreachRDD { rdd =>
rdd.joinWithCassandraTable( "keyspace", "table" ).map{ ...
}
}
所以问题是如何用cassandra表实现左外部联接?
So the question is how can I implement left outer join with cassandra table?
预先感谢
推荐答案
当前不支持此功能，但是有介绍该功能的票证.如果您希望将来引入它，请对其进行投票.
This is currently not supported, but there is a ticket to introduce the functionality. Please vote on it if you would like it introduced in the future.
https://datastax-oss.atlassian.net/browse/SPARKC-181
故障单中建议一种解决方法
A workaround is suggested in the ticket
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