primary key

Which of the following is NOT a superkey in a relational schema with attributes $$V, W, X, Y, Z$$ and primary key $$V Y?$$

Consider a relation table with a single record for each registered student with a single record for each registered student with the following attributes. $$1.$$ $$Registration$$ $...

Consider the relations r 1 (P, Q, R) and r 2 (R, S, T) with primary keys P and R respectively. The relation r 1 contains 2000 tuples and r 2 contains 2500 tuples. The maximum size...

Consider the relation "enrolled (student, course)" in which (student, course) is the primary key, and the relation "paid (student, amount)" where student is the primary key. Assume...

Consider the following relation schema pertaining to a students database: Students ( rollno , name, address) Enroll( rollno,courseno , coursename) Where the primary keys are shown...