title: hive fetch result from hdfs is too slow, because of too many the map only task, How can I merge the query result When hive SQL query is executed
body: <p>hive query produces too many result files in the fold of &quot;/tmp/hive/hive&quot;, Close to 4W tasks.But the total number of running results is only more than 100
  so I wonder if there is a way to merge the results after query, reduce the number of result files, and improve the efficiency of pulling results?</p>
  <p>Here is the explain of the query</p>
  <pre><code>+----------------------------------------------------+--+
  |                      Explain                       |
  +----------------------------------------------------+--+
  | STAGE DEPENDENCIES:                                |
  |   Stage-1 is a root stage                          |
  |   Stage-0 depends on stages: Stage-1               |
  |                                                    |
  | STAGE PLANS:                                       |
  |   Stage: Stage-1                                   |
  |     Map Reduce                                     |
  |       Map Operator Tree:                           |
  |           TableScan                                |
  |             alias: kafka_program_log             |
  |             filterExpr: ((msg like '%disk loss%') and (ds &gt; '2022-05-01')) (type: boolean) |
  |             Statistics: Num rows: 36938084350 Data size: 11081425337136 Basic stats: PARTIAL Column stats: PARTIAL |
  |             Filter Operator                        |
  |               predicate: (msg like '%disk loss%') (type: boolean) |
  |               Statistics: Num rows: 18469042175 Data size: 5540712668568 Basic stats: COMPLETE Column stats: PARTIAL |
  |               Select Operator                      |
  |                 expressions: server (type: string), msg (type: string), ts (type: string), ds (type: string), h (type: string) |
  |                 outputColumnNames: _col0, _col1, _col2, _col3, _col4 |
  |                 Statistics: Num rows: 18469042175 Data size: 5540712668568 Basic stats: COMPLETE Column stats: PARTIAL |
  |                 File Output Operator               |
  |                   compressed: false                |
  |                   Statistics: Num rows: 18469042175 Data size: 5540712668568 Basic stats: COMPLETE Column stats: PARTIAL |
  |                   table:                           |
  |                       input format: org.apache.hadoop.mapred.TextInputFormat |
  |                       output format: org.apache.hadoop.hive.ql.io.HiveIgnoreKeyTextOutputFormat |
  |                       serde: org.apache.hadoop.hive.serde2.lazy.LazySimpleSerDe |
  |                                                    |
  |   Stage: Stage-0                                   |
  |     Fetch Operator                                 |
  |       limit: -1                                    |
  |       Processor Tree:                              |
  |         ListSink                                   |
  |                                                    |
  +----------------------------------------------------+--+
  </code></pre>