SQL HAVING – Definition, Query, Syntax, Example

This tutorial is shared to learn SQL HAVING statement with definition, query, syntax & example. Even You will learn to use it with aggregate functions like COUNT(), SUM(), MAX, MIN() & AVG().

The HAVING clause always executes in the SELECT statement with the GROUP BY clause and returns the result of grouped values based on conditions. So, Before learning it, you must have a basic knowledge of the GROUP BY clause.

sql having

What is SQL HAVING Clause

 Definition – The SQL Having clause returns by grouping values based on specified conditions using aggregate functions

Learn also –

SQL Interview Questions and Answers

You must memorize the following points –

  • GROUP BY clause is required to execute the HAVING statement.
  • The HAVING always comes with aggregate functions like COUNT(), SUM(), MIN(), MAX() & AVG()
  • HAVING Clause is always used with a SELECT Statement.
  • You should use  HAVING after WHERE GROUP BY clause if you need to use it.
  • You should also use HAVING before the ORDER BY clause if you need to use it.

 

SQL HAVING Syntax

This SQL HAVING syntax is created with two columns of a table. once, you learn, You definitely create for more columns.

SELECT column_name1, column_name2,...
FROM table_name
WHERE condition
GROUP BY column_name1, column_name2...
HAVING condition
ORDER BY column_name1, column_name2...;

SQL HAVING Example

I have created a table employees with duplicate values for a SQL HAVING example. This table has five columns like empolyee_idfull_namegendercity &  salary.

You can create a table using the following query.

CREATE TABLE employees
      (
      employee_id int(10) PRIMARY KEY NOT NULL AUTO_INCREMENT,
      full_name varchar(50),
      gender varchar(20),
      city  varchar(100),
      salary int(10)
      );

You can also insert some values in employees table using the following query

INSERT INTO employees( full_name, gender, city, salary) VALUES 
( 'Noor Khan', 'Male', 'Patna', 30000),
('Sunil Kumar', 'Male', 'New Delhi', 45000), 
( 'Monika Singh', 'Female', 'Chennai', 30000), 
('Aaliya Khan', 'Female', 'Chennai', 40000),
( 'Sunil Kumar', 'Male', 'Patna', 25000),
('Monika Singh', 'Female', 'New Delhi', 60000),
('Rapson Jani', 'Male', 'Patna', 70000), 
('Rapson Jani', 'Male', 'New Delhi', 25000), 
('Sunil Kumar', 'Male', 'Patna', 65000),
('Monika Singh', 'Female', 'Patna', 32000);

Table Structure –

This is the table structure with some data of employees

Table Name – employees

 

employee_id full_name gender city salary
201 Noor Khan Patna 30,000
202 Sunil Kumar New Delhi 45,000
203 Monika Singh Chennai 30,000
204 Aaliya Khan Chennai 40,000
205 Sunil Kumar Patna 25,000
206 Monika Singh New Delhi 60,000
207 Rapson Jani Patna 70,000
208 Rapson Jani New Delhi 25,000
209 Sunil Kumar Patna 65,000
210 Monika Singh Patna 32,000

Query –

If you need to know the names of the city in which more than 2 employees live, use the following query

SELECT city, COUNT(full_name) FROM employees 
GROUP BY city
HAVING COUNT(full_name)>2;

Output –

city COUNT(full_name)
New Delhi 3
Patna 5

SQL HAVING Aggregate Functions

You have already learned in the previous step that the HAVING  clause needs aggregate functions to returns the result of grouped values. Now, You will see it with an example

GROUP BY COUNT()

If you need to know the total number of records of any specified column based on the HAVING clause, use the COUNT() function.

Example – 

We have to display only full names of more than two employees who have the same name.

Query –

SELECT full_name, COUNT(full_name) FROM employees 
GROUP BY full_name
HAVING COUNT(full_name)>2;

Output –

full_name COUNT(full_name)
Sunil Kumar 3
Monika Singh 3

HAVING SUM()

If you need to know the total sum values of any specified column based on the HAVING clause, use the SUM() function.

Example – 1

We have to add total salary employees who have the same name and total salary must be greater than 40,000

Query –

SELECT full_name, SUM(salary) FROM employees 
GROUP BY full_name
HAVING  SUM(salary)>40000

Output –

full_name SUM(salary)
Monika Singh 122000
Rapson Jani 35000
Sunil Kumar 135000

 

HAVING MIN()

If you need to know the lowest value of any specified column based on the HAVING clause, use MIN() function.

Example –

We have to display maximum salary employees who have the same name and Maximum salary must be greater than 40,000

Query –

SELECT full_name, MAX(salary) FROM employees 
GROUP BY full_name
HAVING  MAX(salary)>40000

Output –

full_name MAX(salary)
Monika Singh 60000
Rapson Jani 70000
Sunil Kumar 65000

HAVING MAX()

If you need to know the largest value of any specified column based on the HAVING clause, use the MAX() function.

Example –

We have to display minimum salary employees who have the same name and Minimum salary must be less than 30,000

Query

SELECT full_name, MIN(salary) FROM employees 
GROUP BY full_name
HAVING  MIN(salary)<30000

Output –

+----------------+---------------- -----+
|  full_name     |   MIN(salary)        |
+----------------+----------------------+
|  Rapson Jani   |    25000             |
|  Sunil Kumar   |    25000             |
+----------------+----------------------+

HAVING AVG()

If you need to know the average value of any specified column based on the HAVING clause, use the AVG() function.

Example –

We have to display average salary employees who have the same name and Average salary must be greater than 40,000

Query –

SELECT full_name, AVG(salary) FROM employees 
GROUP BY full_name
HAVING  AVG(salary)>40000

Output –

full_name AVG(salary)
Monika Singh 40666.66
Rapson Jani 47500
Sunil Kumar 45000

SQL HAVING with different clauses

In some cases, You may need to use SQL HAVING statement with WHERE & ORDER BY clause. So, you should know about it with an example

HAVING with WHERE Clause

You may use the HAVING clause with the WHERE clause. Let’s understand it through the following Syntax & example

Syntax –

SELECT column_name1, column_name2..
FROM table_name
WHERE condition
GROUP BY column_name1, column_name2..
HAVING condition;

Example –

We have to display only full names of more than two employees who have the same name and those employees must be Male.

Query – 

SELECT full_name, COUNT(full_name) FROM employees
WHERE gender='Male'
GROUP BY full_name
HAVING COUNT(full_name)>2;

Output –

full_name COUNT(full_name)
Monika Singh 3

HAVING with ORDER BY Clause

You may also use the HAVING clause with the ORDER BY clause. Let’s understand it through the following syntax & example.

Syntax –

SELECT column_name1, column_name2.. 
FROM table_name 
GROUP BY column_name1, column_name2.. 
HAVING condition;
ORDER BY column_name1, column_name2..

Example –

We have to display maximum salary employees who have the same name. A maximum salary must be in descending order and greater than 40,000.

Query –

SELECT full_name, MAX(salary)
FROM employees 
GROUP BY full_name 
HAVING MAX(salary)>40000
ORDER BY salary DESC;

Output –

full_name MAX(salary)
Rapson Jani 70,000
Sunil Kumar 65,000
Monika Singh 60,000

HAVING with WHERE and ORDER BY clause

You may also use the HAVING clause with both WHERE & ORDER BY clause. Let’s understand it through the following syntax & example.

Syntax –

SELECT column_name1, column_name2.. 
FROM table_name 
WHERE condition 
GROUP BY column_name1, column_name2.. 
HAVING condition; 
ORDER BY column_name1, column_name2..

Example –

We have to display maximum salary employees who have the same name. Those employees must be Male and A maximum salary must be in descending order & greater than 40,000.

Query –

SELECT full_name, MAX(salary)
FROM employees 
WHERE gender='Male'
GROUP BY full_name 
HAVING MAX(salary)>40000
ORDER BY salary DESC;

Output –

full_name MAX(salary)
Rapson Jani 70,000
Sunil Kumar 65,000

How to Execute SQL HAVING clause

To execute SQL HAVING, you have to configure the following points –

  • First of all, install  SQL server package in your computer
  • Create a MySQL Database like my_db
  • Create a table like employees  in MySQL database
  • Insert some records in the created table
  • Write a SELECT query command with HAVING, WHERE, GROUP BY, & ORDER BY clause
mysql>CREATE DATABASE my_db;
mysql>USE my_db;
mysql>CREATE TABLE employees
      (
      full_name varchar(50),
      gender varchar(20),
      city  varchar(100),
      salary int(10)
      );
mysql>INSERT INTO employees( full_name, gender, city, salary) VALUES 
( 'Noor Khan', 'Male', 'Patna', 30000),
('Sunil Kumar', 'Male', 'New Delhi', 45000), 
( 'Monika Singh', 'Female', 'Chennai', 30000), 
('Aaliya Khan', 'Female', 'Chennai', 40000),
( 'Sunil Kumar', 'Male', 'Patna', 25000),
('Monika Singh', 'Female', 'New Delhi', 60000),
('Rapson Jani', 'Male', 'Patna', 70000), 
('Rapson Jani', 'Male', 'New Delhi', 25000), 
('Sunil Kumar', 'Male', 'Patna', 65000),
('Monika Singh', 'Female', 'Patna', 32000);

mysql>SELECT full_name, MAX(salary)
FROM employees 
WHERE gender='Male'
GROUP BY full_name 
HAVING MAX(salary)>40000
ORDER BY salary DESC;

 

Tutorial Summary

Dear Developer, I have this tutorial according to my working experience. I hope that You have learned how to use SQL HAVING clause with SELECT statement.

If you have any questions related to SQL, Kindly ask me through the comment box. Even you can suggest sharing another web development tutorial.

Categories SQL

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