# “CODASYL Data-Base Management Systems” A 1976 [tutorial paper](http://www.inf.fu-berlin.de/lehre/SS03/datenbanken/DBSReader/codasylDBS.pdf) by Robert W. Taylor and Randall L. Frank covering a [DBMS](/databases) 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_. ## Page metadata URL: Published 2021-02-28, updated 2021-08-21. Tags: - data - databases - notes Index: [Reading notes and reviews](/notes).