(a) Consider again Question 3 in Tutorial 1 (Challenge) to find the restaurants that sell all the pizzas that Maggie likes and don’t sell any pizza that Ralph likes. Write a relational algebra ...

(iii) Suppose the relation Likes contains all information about all customers. In other words, if the pair (cname,pizza) is not in the relation Likes, it means that the customer cname dislikes the ...

In this paper, the authors describe a custom relational algebra query software environment that enables database instructors to teach relational algebra programming. Instead of defining query ...

Abstract: Relational database systems have succeeded commercially because of their straightforwardness and well-built theoretical foundation. This paper ¿Implementation of Relational Algebra ...

Abstract: Imprecision and uncertainty in data values are pervasive in real-world environments and have received much attention in the literature. Several methods have been proposed for incorporating ...