Say you have a table such as:
id foreign_key status
------------------------
1 1 new
2 1 incative
3 1 approved
4 2 new
5 2 new
6 2 approved
7 3 new
8 3 approved
9 4 approved
How to find records where the for a given foreign_key there is only one record in status new and the other are approved, like in case of foreign_key 3?