# IS NULL

## Syntax

```sql
IS NULL
```

## Description

Tests whether a value is `NULL`. See also [NULL Values in MariaDB](https://mariadb.com/docs/server/reference/data-types/null-values).

## Examples

```sql
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](https://mariadb.com/docs/server/server-management/variables-and-modes/server-system-variables#sql_auto_is_null) variable to `1`.

```sql
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](https://mariadb.com/docs/server/reference/data-types/null-values)
* [IS NOT NULL operator](https://mariadb.com/docs/server/reference/sql-structure/operators/comparison-operators/is-not-null)
* [COALESCE function](https://mariadb.com/docs/server/reference/sql-structure/operators/comparison-operators/coalesce)
* [IFNULL function](https://mariadb.com/docs/server/reference/sql-functions/control-flow-functions/ifnull)
* [NULLIF function](https://mariadb.com/docs/server/reference/sql-functions/control-flow-functions/nullif)
* [CONNECT data types](https://mariadb.com/docs/server/server-usage/storage-engines/connect/connect-data-types#null-handling)

<sub>*This page is licensed: GPLv2, originally from*</sub> [<sub>*fill\_help\_tables.sql*</sub>](https://github.com/MariaDB/server/blob/main/scripts/fill_help_tables.sql)

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