title: what is the purpose of split-by <column> --target-dir in Sqoop
body: <p>What happens internally when we write <code>--split-by</code> in sqoop?</p>
  
  <p>Example:</p>
  
  <pre><code>sqoop import --connect jdbc:mysql://localhost/test --username root --password training123 --query 'select * from  transaction where $CONDITIONS' --split-by Txnid --target-dir input/transaction
  </code></pre>