Purpose

ISNULL allows the function to test for a null data condition in data buffers.
 

Syntax

ISNULL (variable{,variable}…)
 

Operation

variable is a valid alphanumeric or numeric variable.
 

Remarks

The function tests each variable in the list for null data.  If any of the variables have null data, the function returns a True value, otherwise, it returns False.

Since PROIV does not automatically recognize null data, it is left to you to test fields that may possibly contain null values.  Otherwise PROIV could perform operations which are undefined for null values
 

Example

IF ISNULL (ITEM) THEN ITEMCOST = -999;