SQL: How do you select only groups that do not contain a certain value?

Question

Say I have a table:

Restaurant locations: 

RESTAURANT_NO | RESTAURANT_LOCATION
-----------------------------------
1             |            City A
1               


        

Answer 1

One way:

SELECT RESTAURANT_NO FROM restaurant WHERE RESTAURANT_NO NOT IN
(SELECT RESTAURANT_NO FROM restaurant WHERE RESTAURANT_LOCATION = 'City C')