16
The JOIN operator can be specified as :

Answer: Option [C]

Questions

18
If P and Q are predicates and P is the relational algebra expression, then which of the following equivalences are valid ?

Answer: Option [D]

20
Relational calculus is :

I. equivalent to relational algebra in its capabilities.

II. it is stronger than relational algebra.

III. it is weaker than relational algebra.

IV. it is based on predicate calculus of formal logic.

Now answer which one is correct option ?

Answer: Option [D]