IS NULL

Syntax

IS NULL

Description

Tests whether a value is NULL. See also NULL Values in MariaDB.

Examples

SELECT 1 IS NULL, 0 IS NULL, NULL IS NULL;
+-----------+-----------+--------------+
| 1 IS NULL | 0 IS NULL | NULL IS NULL |
+-----------+-----------+--------------+
|         0 |         0 |            1 |
+-----------+-----------+--------------+

Compatibility

Some ODBC applications use the syntax auto_increment_field IS NOT NULL to find the latest row that was inserted with an autogenerated key value. If your applications need this, you can set the sql_auto_is_null variable to 1.

SET @@sql_auto_is_null=1;
CREATE TABLE t1 (auto_increment_column INT NOT NULL AUTO_INCREMENT PRIMARY KEY);
INSERT INTO t1 VALUES (NULL);
SELECT * FROM t1 WHERE auto_increment_column IS NULL;

+-----------------------+
| auto_increment_column |
+-----------------------+
|                     1 |
+-----------------------+

See also

• NULL values
• IS NOT NULL operator
• COALESCE function
• IFNULL function
• NULLIF function
• CONNECT data types