Relational Algebra Operations - Binary

Introduction to Binary Relational Algebra Operations

In this section,# Introduction to Binary Relational Algebra Operations

In this section, we will learn about the binary relational algebra operations - join and division. We will start by understanding what the join operation does.

Join Operation

• The join operation combines tuples or rows from two relations into a single relation based on a given join condition.

• To perform a join operation between two relations, we write the first relation followed by the join operator and the join condition in the subscript followed by the second relation name.

• An example of using a join operation is when we want to retrieve details of managers of each department. We have to combine each department tuple with employee tuples and then check if their assistant values match.

• A cartesian product followed by selection can be used instead of the join operator, as it gives the same result.

Theta Join

• The theta join is an extension of the basic join operation where we use any one of the comparison operators such as equal to, less than, greater than, etc., in place of equality in the joint condition.

Overall, this section provides an introduction to binary relational algebra operations and focuses on explaining how to perform a basic and theta joins between two relations.