How can I group multiple records as a single .csv string line?

I have a relation where a User has multiple dogs (as many as 15) but each dog is contained in a single row in the table, and they all have a userId in common. For example, Table dogs: | User | Dog Name | Age | ABCD | Fido | 7 | ABCD | Gooofy | 9 | ABCD | Toto | 4 | ABCD | Roger | 12 | ABCD | Barkley | 3 I would like to do something like SELECT * FROM dogs GROUP BY User where the result will output a csv of ABCDs dogs, as follows: ABCD, Fido, 7, Goofy, 9, Toto, 4, Roger, 12, Barkley, 3 I'm using BigQuery but I think knowing how to do this in PostgreSQL may even be helpful. So maybe I can create some sort of view or something?