Example (In PostgreSQL):
CREATE FUNCTION foo(a int, b int, c int) RETURNS int
LANGUAGE plpgsql AS
$$
BEGIN
RETURN a + b + c;
END
$$;
SELECT foo(a => 1, b => 2, c => 3);
-- `3` goes after the named argument
SELECT foo(1, b => 2, 3);
-- `1` and `3` go after the named argument
SELECT foo(b => 2, 1, 3);