In OData, a navigation property is a property on an entity that is itself either a single entity or list of entities.
A single-entity navigation property signifies a one-to-one relationship. For example, SAP SuccessFactors has the entity JobApplication which contains an Eduction navigation property, which references a single JobApplicationSnapshot_Education entity.
An entity set navigation property signifies a one-to-many relationship. For example, in SAP SuccessFactors, the JobApplication has a Langauges navigation property which can reference many JobApplicationSnapshot_Languages objects.
Working with Navigation Properties Relationally
Navigation properties in OData link related entities. Similarly, in a relational database, a foreign key serves to link tables. For example, the JobApplicationSnapshot_Language record contains the applicationId column, which uniquely identifies what JobApplication the JobApplicationSnapshot_Language belongs to.
It can be used to retrieve related entites that do not exist by themselves such as the emailTypeNav on PerEmail. See Views for more information on querying navigation properties.
The add-in supports OData deep inserts. See Tables for more information on specifying navigation properties when you create an entity.