Modifying Access Paths › Modifying Virtual Field Entries › Specifying File and Access Path Relations

Specifying File and Access Path Relations

Specifying virtual fields is a two level process: For a field to be used as a virtual field, you must specify it as a virtual field on both the file relations and the access path relations.

In the previous example, the field Branch address is not available as a virtual field on any access path of the Customer file, as it is not specified as a field on the relations for the file.

For more information about:

• Specifying virtual fields on a file, see the Adding/Modifying Virtual Fields section in the "Maintaining Your Data Model" chapter of Defining a Data Model.
• Specifying virtual fields on an access path, see the Tailoring Virtual Fields for Access Paths section later in this chapter.

The following example shows how access paths can have subsets of the relations on the file: