Maintaining Your Data Model › Creating User-Defined Field Types › Defining Parameters for the Mapping Functions

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Defining Parameters for the Mapping Functions

You use the Edit Function Parameter and Edit Function Parameter Detail panels to specify the parameters for mapping functions.

The two mapping functions for the DTX field data type, Check DTX and Convert DTX, should have parameters defined for them as follows:

Function
Name

 

FIRST PARAMETER

 

 

SECOND PARAMETER

 

 

 

Function
Type

Name

Usage

Data
Type

Name

Usage

Data
Type

Check DTX

Ext/Int

Century

external

I

NBR

8.0

Century

internal

O

 

Convert DTX

Int/Ext

Century

external

I

 

 

O

DTX

8.0

 

 

 

O

NBR

8.0

Century

internal

I

DTX

8.0

The fields Century internal and Century external are used only to define the parameters on the century data type mapping functions. They can be defined with the Define Objects panel and should be of the same data type (packed, zoned, alphanumeric, etc.) and size as the respective internal and external formats of the field data type. For the DTX field, both internal and external formats are numeric. The Century internal field could itself be a field of type DTX.

If necessary, use the Define Objects panel to define fields of appropriate data types to use as parameter fields on the mapping functions.