ROWNUM is not available in this context

  Explanation:  You have used ROWNUM and have violated one of the
  restrictions.  The restrictions are, ROWNUM:  can only be used
  in ORACLE LEVEL1 dialect can only be used in a comparison of
  select expression predicate cannot be used with a LIMIT TO
  clause cannot appear more than once in the predicate of a WHERE
  clause can only appear in SELECT statements cannot be compared
  to a column cannot be used in a compound statement cannot appear
  on either side of an OR boolean operator cannot be selected or
  used in a function call

  User Action:  Re-issue the query and adhere to the restrictions.