Relational Algebra
Q31.
With regard to the expressive power of the formal relational query languages, which of the following statements is true ?Q32.
Consider the relations r1(P, Q, R) and r2(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 of the join r_{1} \Join r_{2} is :Q33.
Consider the relation Student (\underline{name}, sex, marks), where the primary key is shown underlined, pertaining to students in a class that has at least one boy and one girl. What does the following relational algebra expression produce) (Note: \rho is the rename operator). The condition in join is "(sex=female ^\wedge x=male ^\wedge marks\leq m)"