THIS IS A TEST INSTANCE. ALL YOUR CHANGES WILL BE LOST!!!!
...
At first, let's take a look at three examples. For every query, we show the original operator tree generated by Hive and the optimized operator tree. To be concise, we only show the following operators, which are FileSinkOperator (FS)
, GroupByOperator (AGG)
, HashTableSinkOperator (HT)
, JoinOperator (JOIN)
, MapJoinOperator (MJ)
, and ReduceSinkOperator (RS)
. Also, in every query, we add comments (e.g. /*JOIN1*/
) to indicate the node in the operator tree that an operation belongs to.
...