Com relação ao banco de dados happyhour, considere que ho

A

delete from frequencia

where oferta.bar <> frequencia.bar

B

delete from frequencia

from oferta

where oferta.bar <> frequencia.bar

C

delete from frequencia

where bar in (select bar from oferta)

D

delete from frequencia

where not exists

           (select * from oferta f

            where f.bar = frequencia.bar)

E

delete from frequencia

where bar = (select bar from oferta

                     where bar is null)