Relation Resolving 

The core service provided to the portal by unification is relation resolving between business objects. During navigation, queries may be launched by means of Drag&Relate, context menu (right-click and relate), or by simply clicking an iView. The relationships between the business objects involved in these navigation actions form the paths along which queries are completed and result sets returned.

Relations: General Information

A relationship is a defined logical link between two objects, usually manifested by identical properties.

Types of Relations

Unification deals with three possible types of relations between business objects:

Manual	A manually created relation between two objects, defined by the content administrator. These include newly defined relationships between two previously unrelated objects, and existing relationships that are redefined. For more information on manual relations, see Relationship Editor.
Foreign Key	Often a link between a property of one object to a primary key property of another. However, in the context of unification, this mainly refers to a relation that is defined in the back-end application. It may represent an R/3 remote function call or a predefined relation between two separate systems.
Automatic	An automatically generated link between two business objects that are not directly related by means of a foreign key. Automatic relations are generated by the unification autocomplete service. For more information, see Autocompleting Relations.

Relation Resolving Service

The relation resolving service is the module of the portal unification infrastructure that returns relations between business objects. The relation resolving service may obtain the relations from varying locations and according to a specific logic. This information is transparent to the content administrator during design time, but it may be useful for the administrator to be aware of it.

Relation Storage and Search Precedence

When presented with two business objects, A and B, the relation resolving service searches for a relation between them in the following order and locations:

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       1.      A manual relation is searched for first in the Portal Content Directory (PCD).

In the event of multiple relations, the relation resolving service returns all existing relations, unless a default relation has been specified. For more information, see Single Relation Editor.

       2.      If a manual relation is not found, a direct relation, such as a foreign key relation, is searched for by turning to the Distributed Query Engine (DQE), which obtains these from the back end.

For more information about the DQE, see Administration of the Distributed Query Engine (DQE).

       3.      Lastly, automatic relations are searched for by the autocomplete service, a sub-service of the relation resolving service.

An automatic relation is a chain of relations from A to B by going through other business objects C,D and E, which relate directly one to the other until the relation is complete. Automatic, or autocomplete relations are found on-the-fly by the relation resolving service and saved in memory and cached. They are kept until the cache is refreshed.

For more information on automatic relations, see Autocompleting Relations.