Suppose we have a database consisting of the following three relations.
- $\text{FREQUENTS (student, parlor)}$ giving the parlors each student visits.
- $\text{SERVES (parlor, ice-cream)}$ indicating what kind of ice-creams each parlor serves.
- $\text{LIKES (student, ice-cream)}$ indicating what ice-creams each student likes.
(Assume that each student likes at least one ice-cream and frequents at least one parlor)
Express the following in SQL:
Print the students that frequent at least one parlor that serves some ice-cream that they like.