How the product fits together

OS MasterMap Highways Network – RAMI is a relational product. This results in there being relationships between different feature types. This section summarises how the different feature types relate to one another, and which attributes are the primary and foreign keys for the RAMI feature. For information on the Roads features, please see the Roads Technical Specification.

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

Source Feature Type	Foreign Key Attribute	Destination Feature Type	Primary Key Attribute
Feature type	—	feature type	—
AccessRestriction	element	RoadLink	id
TurnRestriction	element	RoadLink	id
RestrictionForVehicles	element	RoadLink	id
RestrictionForVehicles	element	RoadNode	id
RestrictionForVehicles	linkReference	RoadLink	id
Hazard	element	RoadLink	id
Hazard	element	RoadNode	id
Hazard	linkReference	RoadLink	id
Structure	element	RoadLink	id
Structure	element	RoadNode	id
Structure	linkReference	RoadLink	id
Maintenance	element	Street	id
Reinstatement	element	Street	id
SpecialDesignation	element	Street	id
HighwayDedication	element	Street	id
HighwayDedication	element	RoadLink	id

OS MasterMap Highways Network – Routing and Asset Management Information relational model