To union or union all, that is the question

Question

I have two queries that I\'m UNIONing together such that I already know there will be no duplicate elements between the two queries. Therefore, UNION a

Answer 1

According to http://blog.sqlauthority.com/2007/03/10/sql-server-union-vs-union-all-which-is-better-for-performance/ at least for performance it is better to use UNION ALL, since it does not actively distinct duplicates and as such is faster