Relations¶
Relations do not store data on the system. They relate groups of resource types such as device models and data models.
The purpose of a Relation is to provide a model type that can group together related models and then carry out operations on them. Model types are related by joining them similarly to a SQL “left join”. One or more fields can be specified as foreign keys.
A relation of relations is not supported.
A Relation will show all the attributes of its model types by default. Even fields specified as foreign keys will appear for each of their respective model types. Unwanted attributes are hidden using a Field Display Policy, and default values of hidden attributes can be assigned using a Configuration Template.
Operations are added to Relations. Operations with associated workflows will execute their custom workflow. Add, modify and delete operations without workflows will execute a dynamic workflow that simply adds, modifies, or deletes all related model instances. However, if a Relation for example contains shared Phones or Lines (as the Subscriber relation), then these related model instances are not deleted.