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MySQL - COUNT() function example
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In this article, we would like to show you how to use COUNT() function in MySQL.
Quick solution:
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SELECT COUNT(*) AS `alias_name` FROM `table_name`;To show how the COUNT() function works, we will use the following table:
Note:
At the end of this article you can find database preparation SQL queries.
In this example, we will display the number of users.
Query:
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SELECT COUNT(*) AS `number of users` FROM `users`;Output:
create_tables.sql file:
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CREATE TABLE `users` (2
`id` INT(10) UNSIGNED NOT NULL AUTO_INCREMENT,3
`name` VARCHAR(50) NOT NULL,4
`surname` VARCHAR(50) NOT NULL,5
`department_id` INT(10) UNSIGNED,6
`salary` DECIMAL(15,2) NOT NULL,7
PRIMARY KEY (`id`)8
);insert_data.sql file:
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INSERT INTO `users`2
( `name`, `surname`, `department_id`, `salary`)3
VALUES4
('John', 'Stewart', 1, '3512.00'),5
('Chris', 'Brown', 2, '1344.00'),6
('Kate', 'Lewis', 3, '6574.00'),7
('Ailisa', 'Gomez', NULL, '6500.00'),8
('Gwendolyn', 'James', 2, '4200.00'),9
('Simon', 'Collins', 4, '3320.00'),10
('Taylor', 'Martin', 2, '1500.00'),11
('Andrew', 'Thompson', NULL, '2100.00');