title: Hive not respecting mapreduce.job.reduces
body: <p>A hive insert statement of the following form:</p>
  
  <pre><code> insert into my_table select * from my_other_table;
  </code></pre>
  
  <p>is using ONE reducer - even though just prior the following had been executed:</p>
  
  <pre><code> set mapreduce.job.reduces=80;
  </code></pre>
  
  <p>Is there a way to force hive to use more reducers? there is not clear reason why this particular query would do a single reducer - given there is no ORDER BY clause at the end.</p>
  
  <p>BTW the source and destination tables are both </p>
  
  <pre><code>  stored as parquet
  </code></pre>