Question

Describe how you would define the relation Brother-in-Law whose tuples have the form (x, y) with x being the brother-in-law of y. b. Give appropriate relational algebra and SQL expressions that return the relation Brother-in-Law.

Answer 1

The expression is :

π[cd) + π(g,h) ],[π(e,f)+π(a,b)])

We will use foreign key and primary key