## Introduction

Relational algebra is one of the most integral parts of the __DBMS__. It is a query language that accepts instances of relations as input and produces instances of relations as output. It makes use of operators to carry out queries. A binary or unary operator can be used. They receive relations as input and produce relations as output.

Recursive relational algebra is conducted on a relation, and intermediate outcomes are also considered relations.

In the upcoming sections, we’ll see different types of Relational algebra operators and then we’ll also solve an example based on Relational algebra.

Let’s see the type of Relational algebra operators now.

Must Recommended Topic, __Generalization in DBMS____.__

Must Recommended Topic, __Schema in DBMS__

## Relational algebra operators:

Let us now have a look at different operators used in Relational algebra

- σ – Selection with conditions.

This operator chooses all tuples that meet the requirements. Displays a whole table with relation to the structure.

- Π – Projection operator.

It displays column(s) that fulfil the given criteria.

- ⨝ - Natural join operator.

A binary operator that connects two relations based on the values of their shared attributes.

- X - Cartesian Product.

This operator merges information from two different relationships into a single one.

- -, ∪, and ∩ - Set operators.

These operators perform the set operations. The operations are difference, union and intersection respectively.

- ρ - Rename Operator.

The outcomes of relational algebra are also relations, although they lack a name. We may rename the output relation using the rename method. The operation rename is symbolised by the little Greek letter rho ρ.

Now its’ time to solve an example.

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