“CODASYL Data-Base Management Systems”

A 1976 tutorial paper by Robert W. Taylor and Randall L. Frank covering a DBMS of historical interest.

• Records have types.
• There is a set type (one record of the owner record type -> N records of the member record type).
• A record cannot occur as a member of two sets of the same set type.
• Can’t model many to many relationships directly because it would lead to a violation of the above rule; we define an auxiliary record type that represents that relationship.
• N-dimensional associations through intersection records.
• Recursive structures are represented through a relationship record type and two relationships: has-substructure and has-superstructure.