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MySQL - count rows with NULL values

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In this article, we would like to show you how to count rows with NULL values in MySQL.

Quick solution:

SELECT COUNT(*) AS 'alias_name'
FROM `table_name`
WHERE `column_name` IS NULL;

Practical example

To show you how to count rows with NULL values, we will use the following users table:

MySQL - example data used to count rows with NULL values
MySQL - example data used to count rows with NULL values

Note:

At the end of this article you can find database preparation SQL queries.

Example

In this example, we will count the number of rows with NULL values in department_id column.

Query

SELECT COUNT(*) AS 'NULL_values_in_column'
FROM `users`
WHERE `department_id` IS NULL;

Result:

MySQL - count rows with NULL values - result
MySQL - count rows with NULL values - result

Database preparation

create_tables.sql file:

CREATE TABLE `users` (
	`id` INT(10) UNSIGNED NOT NULL AUTO_INCREMENT,
	`name` VARCHAR(50) NOT NULL,
	`surname` VARCHAR(50) NOT NULL,
	`department_id` INT(10) UNSIGNED,
    `salary` DECIMAL(15,2) NOT NULL,
	PRIMARY KEY (`id`)
);

insert_data.sql file:

INSERT INTO `users`
	( `name`, `surname`, `department_id`, `salary`)
VALUES
	('John', 'Stewart', 1, '6000'),
	('Chris', 'Brown', 2, '6000'),
	('Kate', 'Lewis', 3, '4000'),
	('Ailisa', 'Gomez', NULL, '4000'),
	('Gwendolyn', 'James', NULL, '4000'),
	('Simon', 'Collins', 4, '4000'),
	('Taylor', 'Martin', 2, '2000'),
	('Andrew', 'Thompson', NULL, '2000');

MySQL - Problems

MySQL - count rows with NULL values
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