How to execute UNION without sorting? (SQL)

Question

UNION joins two results and remove duplicates, while UNION ALL does not remove duplicates.
UNION also sort the final output.

W

Answer 1

You can do something like this.

Select distinct name from  (SELECT r.name FROM outsider_role_mapping orm1 
    union all
SELECT r.name FROM user_role_mapping orm2
) tmp;