PROC SQL follows most of the guidelines set by the American National Standards Institute (ANSI) in its implementation of SQL. However, it is not fully compliant with the current ANSI Standard for SQL.

DATA step views are very versatile because they can harness the power of SAS DATA step processing, including DO loops and IF-THEN-ELSE statements. DATA step views do not have write capability, that is ...

Yes a sproc can return multiple resultsets and you can even work with them in ADO, though it is somewhat esoteric.