Reports whether the value of a column or expression is null.
IsNull ( any )
Argument |
Description |
|---|---|
any |
A column or expression that you want to test to determine whether its value is null |
Boolean. Returns true if any is null and false if it is not.
Use IsNull to test whether a user-entered value or a value retrieved from the database is null.
This expression returns true if either a or b is null:
IsNull(a + b)
This expression returns true if the value in the salary column is null:
IsNull(salary)
This expression returns true if the value the user has entered is null:
IsNull(GetText())
