The development and the exploitation of data models are the basic processes of the database engineeering domain. Models allow database structures to be described at the appropriate level of abstraction, so that schemas can be evaluated, transformed and reasoned about rigourously. They are at the core of design methodologies and CASE tools. The conceptual models, such as the Entity-relationship model and some interpretations of UML class diagrams aim at describing data/information structures at the conceptual, technology-independent level, while the many logical models (relational, object-relational, XML, and the like) currently available are intended to represent data structures as they are implemented by data managers (or by families thereof).
The SPHINX data models. The SPHINX DBMS was based on a hierarchy of two data model. The first one would be qualified, according to the current terminology conceptual [P74-02] and the second one, logical [P74-01], though both were technology independent (I must confess that the titles of the paper are misleading!). The concept of technology-independent (PIM in the MDE vocabulary) logical model was popular in the seventies. This idea was later reused in the GAM, GER and DB-MAIN models. The SPHINX system and its data models are described in project reports [R78-01] to [R78-05].
The Individual model. Reference [P74-04] reports on the first version on the Individual model (a variant of the ER model), which was the main component of the MERISE methodology. This model emerged from hot discussions in a French-Belgian think tank [P74-03]. Hubert Tardieu, the architect of the Merise methodology, was a member of the team (though no co-author of [P74-03]).
The GAM. The Generalized Access Model derived from the early work on technology-independent logical models [P74-01]. This binary model was the basis of three research lines: (1) database performance analysis [P76-02] [P77-01], (2) a first study on schema transformation [P81-02] and (3) logical design methodology [B86].
The GER model. The Generic Entity-relationship model (GER) is a wide-spectrum information/data structure specification model. It encompasses the main concepts and constructs of most popular modeling formalisms, be they value-based or object-based, it has been given a precise semantics via an extended version of the NF2 (non-first normal form, or nested) relational model [P89-1] [P96-08]]. Through a specialization mechanism, such usual models as Entity-relationship, UML class diagrams and ORM can be rigourously specified and compared [7]. Similarly, the GER can be used to define standard data models such as the relational, object-relational, CODASYL, IMS, XML or plain file structure models. The GER model has been used to study transformation-based database engineering processes [P06-10].
The DB-MAIN model. This model is a partial, graphical, implementation of the GER. It has been developed for the DB-MAIN CASE environment. A precise definition can be found in the DB-MAIN manuals [T09-01] and in DB design tutorials [T02-01] [T02-02].
Temporal data models. The DB-MAIN model (conceptual, logical and physical) has been extended to express temporal aspects of data (transaction, valid, bi-temporal). A specific methodology has been designed and code generation rules have been implemented for active relational databases [P01-02]
Relational model (theory). The theoretical aspects of the relational model, in particular the normalization process, have been developed in books [B09] and [BXX-XX]
DBMS models. Descriptions of data models specific to the most popular DBMS are are available in various references. SQL2, SQL3 in [B09], hierarchical or IMS in [P09-02] and [B02-02], network or CODASYL DBTG in [P09-03], [RXX-XX] and [B02-02]
UML data model. UML class diagrams are often proposed to express database schemas. The ability of this formalism de describe conceptual schemas has been studied in references [R02-01] [B09]. It appears that by discarding some ill-designed constructs and by adding a small number of constructs (such as identifiers and other constraints) it is possible de define a variant of UML (DB-UML) quite fitted to database schemas.
Keywords
ER model, Individual model, UML class diagrams, wide-spectrum model, GER model, logical data model, temporal model, relational model, network model, hierarchical model, OO model, OR model, XML model, large schema layout, semantic and statistical aspects of models, IS-A relations
Resources
[B09] Jean-Luc Hainaut. Bases de données - Concepts, utilisation et développement, Dunod, Collection Sciences Sup, Paris, 2009. [book description]
[P09-03] Jean-Luc Hainaut. Network Data Model, in Encyclopedia of Database Systems, Liu, L. and Özsu, T. (Eds), Springer-Verlag, 2009. [full text]
[P09-02] Jean-Luc Hainaut. Hierarchical Data Model, in Encyclopedia of Database Systems, Liu, L. and Özsu, T. (Eds), Springer-Verlag, 2009. [full text]
[P08-05] Anthony Cleve, Jean Henrard, Didier Roland and Jean-Luc Hainaut. Wrapper-based System Evolution - Application to CODASYL to Relational Migration, in Proceedings of the 12th European Conference on Software Maintenance and Reengineering (CSMR’08), pages 13-22, IEEE Computer Society, 2008. [description]
[P06-10] Jean-Luc Hainaut. The Transformational Approach to Database Engineering, in Generative and Transformational Techniques in Software Engineering, Lecture Notes in Computer Science, Volume 4143, pages 95-143, Springer, 2006. [description]
[P05-06] Yannis Tzitzikas and Jean-Luc Hainaut. How to Tame a Very Large ER Diagram (Using Link Analysis and Force-Directed Drawing Algorithms), in Proceedings of the 24th International Conference on Conceptual Modeling, (ER’05), Lecture Notes in Computer Science, Volume 3716, pages 144-159, Springer-Verlag, 2005. [description] [full text]
[T02-01] Jean-Luc Hainaut, First steps in Database design, Technical report, 2002 [full text]
[B02-02] Jean-Luc Hainaut, Introduction to Database Reverse Engineering, May 2002 [full text]
[R02-01] Jean-Luc Hainaut, UML ou ERA : quel modèle pour l'analyse de l'information ?, Technical report, 2002 [full text]
[B02-02] Jean-Luc Hainaut, Introduction to Database reverse Engineering : [DBRE-2002.pdf
[P01-02] Virginie Detienne and Jean-Luc Hainaut. CASE Tool Support for Temporal Database Design, in Proceedings of the 20th International Conference on Conceptual modeling, (ER’01), Lecture Notes in Computer Science, Volume 2224, pages 208-224, Springer-Verlag, 2001. [description] [full text]
[P97-03] Jean-Luc Hainaut, Jean Henrard, Jean-Marc Hick, Didier Roland and Vincent Englebert. Contribution to the Reverse Engineering of OO Applications - Methodology and Case Study, in Proceedings of the IFIP TC2/WG2.6 Seventh Conference on Database Semantics, (DS-7), IFIP Conference Proceedings, Volume 124, pages 131-161, Chapman and Hall, 1997. [description] [full text]
[P96-08] Jean-Luc Hainaut. Specification preservation in schema transformations - Application to semantics and statistics, Data and Knowledge Engineering, 16(1): Elsevier Science Publish., 1996. [description] [full text]
[P96-05] Jean-Luc Hainaut, Jean-Marc Hick, Vincent Englebert, Jean Henrard and Didier Roland. Understanding implementations of IS-A Relations, in Proceedings of 15th International Conference on Conceptual Modeling, (ER’96), Lecture Notes in Computer Science, Volume 1157, pages 42-57, Springer-Verlag, 1996. [description] [full text]
[P96-03] Jean-Luc Hainaut, Didier Roland, Vincent Englebert, Jean-Marc Hick and Jean Henrard. Database Reverse Engineering - A Case Study, in Actes du 2ème Forum International d’Informatique Appliquée, ESIG, 1996. [description] [full text]
[P90-01] Jean-Luc Hainaut. Entity-Relationship models : formal specification and comparison, in Proceedings of the 9th International Conference on the Entity-Relationship Approach (ER’90), pages 53-64, ER Institute, 1990. [description] [full text]
[P89-01] Jean-Luc Hainaut. A Generic Entity-Relationship Model, in Proceedings of the IFIP WG 8.1 Conference on Information System Concepts: an in-depth analysis, pages 109-138, North-Holland, 1989. [description] [full text]
[B86] Jean-Luc Hainaut, Conception assistée des applications informatiques - Conception de la base de données, Masson, 1986. [description]
[P81-01] Yves Delvaux and Jean-Luc Hainaut. Système portable de manipulation de bases de données, in Actes du congrès AFCET 1981, pages 385-395, Editions Hommes et Techniques, 1981. [description] [full text]
[P78-01] Baudouin Charlier. Quelques réflexions concernant les modèles et langages de bases de données, in Actes des communications de l'Ecole d'été 1978 de l'AFCET, pages 176-185, Publication FUNDP, 1978. [full text]
[R78-01] Jean-Luc Hainaut, Baudouin Le Charlier, et al., Système de conception et d'exploitation de bases de données - Volume 1 : Modèles et Langages. Rapport final du projet CIPS I2/15, Institut d'informatique, Université de Namur, 1978
[R78-02]Jean-Luc Hainaut, Baudouin Le Charlier, et al., Système de conception et d'exploitation de bases de données - Volume 2 : Manuel de référence des langages. Rapport final du projet CIPS I2/15, Institut d'informatique, Université de Namur, 1978
[R78-03]Jean-Luc Hainaut, Baudouin Le Charlier, et al., Système de conception et d'exploitation de bases de données - Volume 3 : Une implémentation du modèle d'accès. Rapport final du projet CIPS I2/15, Institut d'informatique, Université de Namur, 1978
[R78-04]Jean-Luc Hainaut, Baudouin Le Charlier, et al., Système de conception et d'exploitation de bases de données - Volume 4 : Le système SPHINX, Utilisation, fonctionnement et description interne. Rapport final du projet CIPS I2/15, Institut d'informatique, Université de Namur, 1978
[R78-05]Jean-Luc Hainaut, Baudouin Le Charlier, et al., Système de conception et d'exploitation de bases de données - Volume 5 : Exemples d'application. Rapport final du projet CIPS I2/15, Institut d'informatique, Université de Namur, 1978
[P77-01] Jean-Luc Hainaut. Some Tools for Data Independence in Multilevel Data Base Systems, in Proceedings of the IFIP WC on Modelling in Data Base Management Systems, pages 187-211, North-Holland, 1977. [description] [full text]
[P76-02] Jean-Luc Hainaut. Evaluation des performances d’une base de données par modèle probabiliste, in Cahier INFORSID, actes de la conférence sur la représentation des systèmes d’information : Maquette, modèle et prototype, volume 2, pages 177-221, Public. IRIA, 1976. [description] [full text]
[P74-04] Claude Deheneffe, Jean-Luc Hainaut and Hubert Tardieu. The Individual Model, in Proceedings of the International Workshop on Data Structure Models for Information Systems, pages 89-118, Presses Universitaires de Namur, 1974. [description] [full text]
[P74-02] Claude Deheneffe, Henri Hennebert and Walter Paulus. A Relational Model for a Data Base, in Proceedings of the IFIP congress 74, pages 1022-1025, North-Holland, 1974. [description] [full text]
[P74-01] Jean-Luc Hainaut and Baudouin Charlier. An Extensible Semantic Model of Data Base and Its Data language, in Proceedings of the IFIP Congress 74, pages 1026-1030, North-Holland, 1974. [description] [full text]