If a MetaProxyProperty related to a MetaProxy is configured to be an ExternalPrimaryKey UBIK® will handle this property of the corresponding Proxy object as an external key property.
Such properties provide the following features:
- Proxy objects can be searched by their external key property;
- Proxy objects can be linked to each other by using their external key properties and an external reference.
External reference
If a MetaProxyProperty has been configured with a Reference it is defined as an external reference. An external reference property links to a Proxy instance via its property value.
Such Proxies (its properties) will automatically reference to the instance of the targeted MetaProxy (as given by the underlying Reference) having the same entry in its external Primary Key property than the given Proxy instance.
 | When using external keys and external references it is not of relevant which object is processed first, as the linking will be done either way by the system! |
 | Only one external primary key property is supported per MetaProxy. Hence, the external primary key can consist of only one MetaProxyProperty. |