Noops. This will fetch the records which has the seq_id "2", "3" for the same app_id.

Note that a same app_id contains different seq_id starting from 1 to n.
Now, I need to get all the app_id's which has only "1". If I execute the query,
select * from .. where seq_id=1.

This will fetch all the app_id ie 21,22,23. But I should get only 22 because this is the one satisfy my requirement.