Operators

Overview

Time: 20 min

Objectives

• Understanding the concepts of Operators using SQL

OPERATORS

The operators help perform operations on the data in the table. They can be used to perform arithmetic operations or filter based on certain conditions.

Consider the below table:

ARITHMETIC OPERATORS:

The arithmetic operators help perform arithmetic operations on the data in the table

Example:

SELECT ProductID, Unit, Price, Price * Unit AS Total_sales, Price % Unit AS Modulo_result FROM Products

COMPARISON OPERATORS:

The comparison operators are used to filter the results based on a condition. They are generally passed in the WHERE clause and filters the result based on the condition provided.

Syntax:

SELECT columns FROMv table_name WHERE condition <comparison_operator_of_choice> value

Examples:

SELECT ProductID, ProductName, Price FROM Products WHERE ProductID <= 15

SELECT ProductID, ProductName, Price FROM Products WHERE Price = 18

LOGICAL OPERATORS:

SQL has three logical operators which can be used to specify more than one condition in the WHERE clause.

The three operators are:

• AND–Returns results when all the specified conditions are true
• OR–Returns results when at least one of the specified conditions are true
• NOT –Returns results when the opposite of conditions are true

Syntax:

SELECT columns FROM table_name WHERE condition1 AND/OR condition2

SELECT columns FROM table_namem WHERE NOTcondition

Examples:

SELECT CustomerName, Country, City, PostalCode
From Customers
Where Country = 'Brazil' AND City = 'São Paulo'

SELECT CustomerName, Country, City, PostalCode
From Customers
Where City = 'Nantes' OR City = 'Paris'

SELECT CustomerName, Country, City, PostalCode
From Customers
Where Not City = 'London'

Key Points

• Familiarize with Arithmetic operations, Comparison operators and Logical Operators