If your Hive database type disappears from the list in the database connection dialog box in Report Designer or Metadata Editor, this probably means that your Pentaho BI Suite For Hadoop license has expired, or the license file has been moved, deleted, or become corrupt. You must install a valid license key in order to reintroduce this functionality in Report Designer.
If you do not update the licence key, all of your existing Hive-based reports will still work; however, you will not be able to change the Hive connection details or create a new Hive connection.