How the product fits together

OS MasterMap Highways Network – Roads is a relational product. This results in there being relationships between different feature types.

The table below identifies how the feature types relate to one another, and which attributes are the primary and foreign keys. This is also represented in the image below. The attribute at the arrowhead is the primary key and the attribute at the base of the arrow is the foreign key.

Source Feature Information	Foreign Key Attribute	Destination Feature Information	Primary Key Attribute
Feature Type	—	Feature Type	—
RoadLink	startNode	RoadNode	id
RoadLink	endNode	RoadNode	id
RoadLink	relatedRoadArea	TopographicArea	TOID
RoadLink	formsPartOf	Road	id
RoadLink	formsPartOf	Street	id
RoadNode	relatedRoadArea	TopographicArea	TOID
Road	link	RoadLink	id
Street	link	RoadLink	id
RoadJunction	node	RoadNode	id
FerryTerminal	element	RoadNode	id
FerryTerminal	element	FerryNode	id
FerryTerminal	refToFunctionalSite	FunctionalSite	id
FerryLink	startNode	FerryNode	id
FerryLink	endNode	FerryNode	id

OS MasterMap Highways Network – Roads relational model