Example
Test whether an expression is NULL:
sql
SELECT ISNULL(NULL);
Definition and Usage
The ISNULL() function returns 1 or 0 depending on whether an expression is NULL.
If expression is NULL, this function returns 1. Otherwise, it returns 0.
Syntax
text
ISNULL(expression)
Parameter Values
| Parameter | Description |
|---|---|
| expression | Required. The value to test |
Technical Details
| Works in: | From MySQL 4.0 |
|---|
More Examples
Example
Test whether an expression is NULL:
sql
SELECT ISNULL("");
Example
Test whether an expression is NULL:
sql
SELECT ISNULL(350);
Example
Test whether an expression is NULL:
sql
SELECT ISNULL("Hello world!");