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MySQL - search for NULL values in multiple columns
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In this article, we would like to show you how to find rows with NULL values in many columns in MySQL.
Quick solution:
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SELECT *2
FROM `table_name` 3
WHERE `column1` IS NULL AND `column2` IS NULL AND `columnN` IS NULL;xxxxxxxxxx1
SELECT *2
FROM `users`3
WHERE COALESCE(`column1`, `column2`) IS NULL;To show how to find rows with NULL values in many columns, 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 select all rows with NULL value both in email and department_id column using IS NULL and AND keywords.
Query:
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SELECT *2
FROM `users`3
WHERE `email` IS NULL AND `department_id` IS NULL;Result:
In this example, we will select all rows with NULL value both in email and department_id column using COALESCE() function.
Query:
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SELECT *2
FROM `users`3
WHERE COALESCE(`email`, `department_id`) IS NULL;Result:
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
`email` VARCHAR(100),6
`department_id` INT(10) UNSIGNED,7
`salary` DECIMAL(15,2) NOT NULL,8
PRIMARY KEY (`id`)9
);insert_data.sql file:
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INSERT INTO `users`2
( `name`, `surname`, `email`, `department_id`, `salary`)3
VALUES4
('John', 'Stewart', 'john@email.com', 1, '3512.00'),5
('Chris', 'Brown', 'chris@email.com', 2, '1344.00'),6
('Kate', 'Lewis', NULL, 3, '6574.00'),7
('Ailisa', 'Gomez', 'ailisa@email.com', 2, '6500.00'),8
('Gwendolyn', 'James', NULL, NULL, '4200.00'),9
('Simon', 'Collins', NULL, 4, '3320.00'),10
('Taylor', 'Martin', NULL, NULL, '1500.00'),11
('Andrew', 'Thompson', 'andrew@email.com', NULL, '2100.00');