However, this default behavior can cause problems if you attempt to perform arithmetic operations on a database column using a program other than APPX unless the program anticipates the fact that a numeric column may contain null values. For example, if you add two values together and one of the values is null, the result will be null. Many SQL programs will fail if numeric null values are encountered when performing arithmetic.

The default behavior of APPX can be easily changed. If you want APPX to store numeric values of zero as zero instead of null for all database tables, you must toggle on the "Suppress Null Numerics?" option in the FMS Group definition. If this behavior only needs to be changed for selected tables, the option can be set for individual files on the "File Attributes" screen using the "File Specification" program in Database Management.