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 Defining Reference AttributesLocate this document in the navigation structure

Use

Reference attributes are persistent attributes representing references to other persistent objects. To store the type of referenced object, you should assign a class identifier to the reference attribute. This identifier identifies the class of the referenced object and provides an implicit link to the storage location where the required entry is kept. Without this link, the system would have to search through all tables with GUIDs as primary keys.

Procedure
  1. Choose the corresponding table field of type OS_GUID by double-clicking the name of the field.

    The attribute name and description are copied. The system places suggested values in the Visibility, Access, and Assignment type fields. The Attribute type field remains blank.

  2. Change the suggested values:
    • For the assignment type:

      Copy the entry Object reference.

    • For the attribute type:

      Enter the name of the persistent class that the reference refers to.

    • For the attribute name (if required).
    • For the description (if required).
  3. Accept the attribute assignment by pressing Enter .
  4. To assign a class indicator, choose the corresponding table field of type OS_GUID by double-clicking.

    The attribute name and description are copied. The system fills the Visibility, Access, and Assignment type fields with suggested values. The Attribute type field remains blank.

  5. Enter the name of the reference attribute for the attribute name from step 1.
  6. Select Class identifier for the assignment type.
  7. Accept the class identifier by pressing Enter .
  8. Carry out the next step following the procedure in Defining persistence representation .