MariaDB HAVING Clause


Objectives

  • Understanding of MariaDB HAVING Clause

  • MariaDB HAVING Clause


Create database and table and insert data if it is not created already

--- Create database if not exist
CREATE DATABASE IF NOT EXISTS mariadb_tutorial;

--- Select the database for further operation
USE mariadb_tutorial;

--- Create table if not exist
CREATE TABLE IF NOT EXISTS person (
    id int(12) NOT NULL AUTO_INCREMENT,
    first_name varchar(150) NOT NULL,
    last_name varchar(150),
    email varchar(100),
    age int,
    income double,
    PRIMARY KEY (id)
)

--- Remove old Data
TRUNCATE person;

--- Insert data into table if not exist
INSERT INTO person (first_name, last_name, email, age, income)
VALUES
	('Faiyaz', 'Mia', 'faiyaz@pf.local', 10, 5000),
	('John', 'Doe', 'john@pf.local', 19, 100),
	('Tahsin', NULL, 'tahsin@pf.local', 10, 150),
	('Jane', 'Doe', 'jane@gmail.com', 10, 300),
	('Rakib', 'Mia', 'rakib@bf.local', 24, 200),
	('Sagor', 'Sowrov', 'email10@bf.local', 20, 250),
	('Touhid', NULL, 'hmtmcse.com@gmail.com', 30, 500);


Understanding of MariaDB HAVING Clause

In general WHERE keyword cannot be used aggregate functions. The HAVING clause behaves like the WHERE clause and can use aggregate functions. HAVING we mostly use with GROUP BY


MariaDB HAVING Clause

Syntax

SELECT column_name(s) FROM table_name HAVING condition;

Example

SELECT age, COUNT(age) AS total FROM person GROUP BY age HAVING COUNT(age) >= 2;

Output

+------+-------+
| age  | total |
+------+-------+
|   10 |     3 |
+------+-------+
1 row in set (0.097 sec)


MariaDB HAVING Clause Video tutorial

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