Description:
Judge if the value of a parameter is null.
Syntax:
isnull(Exp)
Note:
The function judges whether parameter Exp is a null value.
Parameter:
|
Exp |
An expression of any data type. |
Return value:
Boolean
Example:
|
isnull ("") |
false |
|
isnull (1234) |
false |
|
isnull (null) |
true |