$ pm_xml_db_diff2.pl
<Data>
  <CUSTOMER>
    <CUSTOMER>
      <MODIFIED>
        <KEY name="ABC">
          <CAPTION>
            <newvalue>Premium</newvalue>
            <oldvalue>Regular</oldvalue>
          </CAPTION>
        </KEY>
      </MODIFIED>
      <NEW2>
        <KEY>NEW_CUSTOMER</KEY>
      </NEW2>
    </CUSTOMER>
  </CUSTOMER>
  <EMPLOYEE>
    <EMPDETAILS>
      <MODIFIED>
        <KEY name="DEF">
          <CITY>
            <newvalue>New</newvalue>
            <oldvalue>California</oldvalue>
          </CITY>
        </KEY>
      </MODIFIED>
      <NEW1>
        <KEY>NEW_EMPLOYEE1-DETAILS</KEY>
        <KEY>NEW_EMPLOYEE9-DETAILS</KEY>
        <KEY>NEW_EMPLOYEE16-DETAILS</KEY>
      </NEW1>
      <NEW2>
        <KEY>NEW_EMPLOYEE6-DETAILS</KEY>
      </NEW2>
    </EMPDETAILS>
    <EMPLOYEE>
      <MODIFIED>
        <KEY name="XYZ">
          <TITLE>
            <newvalue>Mr</newvalue>
            <oldvalue></oldvalue>
          </TITLE>
        </KEY>
      </MODIFIED>
      <NEW1>
        <KEY>NEW_EMPLOYEE_1</KEY>
        <KEY>NEW_EMPLOYEE_9</KEY>
      </NEW1>
      <NEW2>
        <KEY>NEW_EMPLOYEE_6</KEY>
      </NEW2>
    </EMPLOYEE>
  </EMPLOYEE>
  <IN_DB1+DB2>
    <IN_DB1+DB2>
      <NEW1>
        <KEY>IN_DB1+DB2</KEY>
      </NEW1>
      <NEW2>
        <KEY>IN_DB1+DB2</KEY>
      </NEW2>
    </IN_DB1+DB2>
  </IN_DB1+DB2>
  <IN_DB1_ONLY>
    <IN_DB1_ONLY>
      <NEW1>
        <KEY>IN_DB1_ONLY</KEY>
      </NEW1>
    </IN_DB1_ONLY>
  </IN_DB1_ONLY>
  <IN_DB2_ONLY>
    <IN_DB2_ONLY>
      <NEW2>
        <KEY>IN_DB2_ONLY</KEY>
      </NEW2>
    </IN_DB2_ONLY>
  </IN_DB2_ONLY>
</Data>