title: Alter Struct Field Datatype in Hive ORC
body: <p>I have 2 years worth of data in a Hive ORC table. One of the column in the table is a struct type.</p>
  <p>Existing - STRUCT&lt;X:DOUBLE, Y:DOUBLE&gt;&gt;</p>
  <p>I want to add new field <strong>Z</strong> to the Struct</p>
  <p>New - STRUCT&lt;X:DOUBLE, Y:DOUBLE, <strong>Z:DOUBLE</strong>&gt;&gt;</p>
  <p>How can I alter the HIVE table to make it backward compatible. On-going data will comply to the new Schema.</p>