# SUFFIX OPERATORS

The `IS NULL` and `IS NOT NULL` operators are used to check whether a column contains a NULL value or not.

## Syntax

`<column> IS NULL`

`<column> IS NOT NULL`

### Parameters

#### column

The column to be checked for NULL values.

## Examples

Finds all employees whose `birth_date` field is NULL.
```esql
FROM employees
| WHERE birth_date IS NULL
```

Counts the number of employees who have a non-NULL value in the `is_rehired` field.
```esql
FROM employees
| WHERE is_rehired IS NOT NULL
| STATS COUNT(emp_no)
```
