Feature relationships

The Relationship Manager tool maintains two types of relationships between objects:

• Hierarchical (master-slave)
• Peer to peer (collections)

With the Relationship Manager tool, you can create, edit, and delete master-slave and collection relationships in your data.

Hierarchical relationships

Hierarchical relationships have designated master and slave features. A master-slave relationship is created to relate features comprising a navigational aid. Navigational aids are composed of two basic types of objects: structures and equipment. The structure object is considered the master feature, and all the related equipment the slave features. A lighted buoy is a good example of a master-slave relationship. The buoy is a master structure with different equipment attached to it, such as lights and navigational devices, which are considered slave features.

To create a master-slave relationship between two points, the two point features must share the same x,y geometry values. However, when line, area, and point geometry type features are grouped into a master-slave relationship, they do not have to share similar geometry values. There could be more than one slave feature, but only one master feature is allowed in a relationship. If you have selected two or more master features when creating a master-slave relationship, you have to choose which one is the master feature from the selection, and the remaining master features become slave features in the relationship.

The following tables list all allowable master-slave feature objects (subtypes in ArcGIS).

Master objects

Master features	Geometry
BCNCAR	Point
BCNISD	Point
BCNLAT	Point
BCNSAW	Point
BCNSPP	Point
BOYCAR	Point
BOYINB	Point
BOYISD	Point
BOYLAT	Point
BOYSAW	Point
BOYSPP	Point
BRIDGE	Point, line, area
BUISGL	Point, area
LITFLT	Point
LITVES	Point
LNDMRK	Point, line, area
MORFAC	Point, line, area
OFSPLF	Point, area
PILPNT	Point
SLCONS	Point, line, area
CRANES	Point, area
FLODOC	Line, area
FORSTC	Point, line, area
FSHFAC	Point, line, area
HULKES	Point, area
PONTON	Line, area
PYLONS	Point, area
SILTNK	Point, area

Master objects

Note:

Master features can also be slave features.

Slave objects

Slave features	Geometry
DAYMAR	Point
LIGHTS	Point
FOGSIG	Point
RADSTA	Point
RDOSTA	Point
RETRFL	Point
RTPBCN	Point
SISTAT	Point
SISTAW	Point
TOPMAR	Point

Slave objects

Note:

Slave features listed in the table above cannot be master features.

Peer-to peer-relationships

In peer-to-peer relationships, no feature's existence is dependent on another. Collections are considered a type of peer-to-peer relationship and can be grouped into two different object classes: aggregations (C_AGGR) or associations (C_ASSO).

Association objects (C_ASSO) depict at least one feature that, when associated, better represents certain navigational situations. For example, a buoy that marks a wreck can be associated in S-57 to help the mariner see that a danger lies in the area. The buoy is not dependent on the wreck nor is the wreck dependent on the buoy.

Aggregation objects (C_AGGR) are collections of features that form a higher-level collection object that better describes a system or defines a larger area. For example, an aggregation relationship can be used to form a traffic separation scheme from traffic separation lane parts, boundaries, and so forth. In the geodatabase, the collection object is stored in the PLTS_COLLECTIONS table, and its relationships to the features that make up the collection are stored in the PLTS_FREL table.