Check if an expression is NULL.
| SELECT ISNULL(NULL); |
The ISNULL() function evaluates whether an expression is NULL, returning 1 for true (if NULL) or 0 for false (if not NULL).
This function returns 1 if the expression is NULL; otherwise, it returns 0.
| ISNULL(expression) |
|
Parameter |
Description |
|
expression |
Required: The value to be evaluated. |
|
Works in: |
From MySQL version 4.0 |
Check if an expression is NULL.
| SELECT ISNULL(“”); |
Determine if an expression is NULL.
| SELECT ISNULL(350); |
Check if an expression is NULL.
| SELECT ISNULL(“Hello world!”); |