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Virtualizing Virtual Fields

The fields you have chosen as virtual fields may themselves be virtual fields on the referenced file.

For more information see the chapter "Creating/Defining Your Data Model."

For instance, if in the above example Product Refers to Quality, with Quality name specified as a virtual field, then Quality name may be a virtual field for Order detail as well.

FIL

FIL

 

Quality

Quality

REF

REF

Known by

Has

FLD

FLD

Quality code

Quality name

CDE

TXT

FIL

 

 

Product

REF

Refers to

FIL

VRT

Quality

Quality name

CDE

TXT

FIL

 

 

Order detail

REF

Refers to

FIL

VRT

VRT

VRT

VRT

Product

Product name

Pack size

Quality code

Quality name

CDE

TXT

QTY

CDE

TXT

You can specify as many levels of virtual fields as allowed by i OS for levels of database join. Depths of three or more are not recommended.

Follow these instructions to add virtual fields to a file relation or modify existing virtual fields.

  1. On the Edit Database Relations panel, type V next to the file relation for which you want to add virtual fields and press Enter.

    The Edit Virtual Field Entries panel displays. This panel shows a list of fields of the referenced file.

  2. Type + next to the field that you want to be a virtual field and press Enter .

    You can add one or many virtual fields for a relation.

    Pressing Enter confirms your selection. Note that an * (asterisk) has been placed in the selection column, indicating the field is now a virtual field.

    To remove a virtual field, type a – next to the selected field.