sql - Select all columns with GROUP BY one column

I have this table:

+----+-----+----------+
| id | name| key      |
+----+-----+----------+
| 1  | foo |111000    |
| 2  | bar |111000    |
| 3  | foo |000111    |
+----+-----+----------+

Is there a way to group by the key to get this result?

+----+-----+----------+
| id | name| key      |
+----+-----+----------+
| 2  | bar |111000    |
| 3  | foo |000111    |
+----+-----+----------+

Or this result:

+----+-----+----------+
| id | name| key      |
+----+-----+----------+
| 1  | foo |111000    |
| 3  | foo |000111    |
+----+-----+----------+

If I use this query:

SELECT * FROM sch.mytable GROUP BY(key);

This is not correct I know that, because I should group by all the columns that I need to show.

Is there a solution for this problem?

Answer

distinct on

select distinct on (key) *
from t
order by key, name

Notice that the order by clause determines which row will win the ties.