Maintaining Your Data Model › Creating User-Defined Field Types › Supplying Parameters to Mapping Functions

Supplying Parameters to Mapping Functions

When a function uses a field with a mapped user-defined field type, calls to the mapping functions are included automatically. The internal and external values are automatically supplied to the required parameters of the mapping functions.

If you specify additional parameters on a mapping function, you must also decide from where the values for those parameters are to be obtained in the functions, which use the field type.

For each parameter you can specify:

• The name of another field present in the same format as the field of the data type (FIL).
• A condition value of a field in the same format as the field of the data type (CND).
• The name of a field in the JOB context.
• A constant value (CON).

The source of field mapping function parameters can be specified at two levels:

• File entry
• Function screen/report entry

  You can also specify whether the values specified at file level may be overridden at a device design level.

To specify the context of the values for any additional parameters on the mapping functions, you use the Field Mapping Function Parameters and the Screen Field Mapping Function Parameters panels.

The Field Mapping Function Parameters panel allows you to specify a default context for the mapping parameters.

The example of the Field Mapping Function Parameters panel below shows how to define the No. of decimals parameter for mapping fields of data type CUR described earlier under "Specifying Additional Parameters for Mapping Functions." Note that you can override the source of the parameter at a lower level.