MapReduce code generated by Hive

Where does Apache HiveQL store the Map / Reduce code it generates?

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I believe that Hive does not actually generate Map / Reduce code in the sense that you might get from Java, because it is interpreted by the query planner in Hive.

If you want to get an idea of ​​what operations are generating your Hive queries, you can prefix your queries with EXPLAIN

and you will see an abstract syntax tree, dependency graph, and plan for each stage. Read more about EXPLAIN

here .



If you really want to see some Map / Reduce jobs, you can try YSmart , which will translate your HiveQL statements into working Java Map / Reduce code. I haven't used it personally, but I know people who have and have talked about it.

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It seems that Hive is changing this method to execute every request.



http://hive.apache.org/docs/r0.9.0/api/org/apache/hadoop/hive/ql/exec/Task.html#execute(org.apache.hadoop.hive.ql.DriverContext)

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