PostgreSQL: u.name must appear in the GROUP BY clause

On lines 575 and 627 appear statements like this:

$sql = "SELECT p.uid, u.name, p.points
FROM {userpoints} p INNER JOIN {users} u USING (uid)
GROUP BY p.uid";

It seems to me that the GROUP clause is not needed as the uid is always unique. In PostgreSQL deleting this clause fixes the "Query failed: ERROR: column 'u.name' must appear in the GROUP BY clause or be used in an aggregate function in" issue.