Multiple choice questions

b

Database Systems Circle the correct answer. 1. A foreign key must always refer to a unique key. a. TRUE b. FASLE 2. If a Primary key consists of more than one attribute, one of its component attributes can be null a. TRUE b. FASLE 3. A relation can have duplicate rows. a. TRUE b. FALSE 4. SQL can result in duplicate rows. a. TRUE b. FALSE 5. In an SQL SELECT statement, we can have HAVING clause even without GROUP BY clause. a. TRUE b. FALSE