It should work (in this case) if you use OUTER JOIN in the view. (I assume that join expression t1.emp_num = t2.emp_name is a typo and should be t1.emp_num = t2.emp_num)

If view doesn't return too many rows you may use it as a derived table:

select t1.sales, t2.emp_name

from sales t1 left outer join (select emp_num, emp_name from v_view1) t2

on t1.emp_num = t2.emp_num