tailieunhanh - Semantic Database Modeling: Survey, Applications, and Research Issues

Each activity (A,B,C,D) is considered as permanent during the 30 months of the project and the different interim reports of the ESPON DB project will propose summaries of main results obtained in the different activities and work-packages. But of course, it is not possible to consider the project as a static structure where all parts are making work independently from each other. That is the reason why we have introduced another level of organization called “challenge”. | Semantic Database Modeling Survey Applications and Research Issues RICHARD HULL Computer Science Department University of Southern California Los Angeles California 90089-0782 ROGER KING Computer Science Department University of Colorado Boulder Colorado 80309 Most common database management systems represent information in a simple record-based format. Semantic modeling provides richer data structuring capabilities for database applications. In particular research in this area has articulated a number of constructs that provide mechanisms for representing structurally complex interrelations among data typically arising in commercial applications. In general terms semantic modeling complements work on knowledge representation in artificial intelligence and on the new generation of database models based on the object-oriented paradigm of programming languages. This paper presents an in-depth discussion of semantic data modeling. It reviews the philosophical motivations of semantic models including the need for high-level modeling abstractions and the reduction of semantic overloading of data type constructors. It then provides a tutorial introduction to the primary components of semantic models which are the explicit representation of objects attributes of and relationships among objects type constructors for building complex types ISA relationships and derived schema components. Next a survey of the prominent semantic models in the literature is presented. Further since a broad area of research has developed around semantic modeling a number of related topics based on these models are discussed including data languages graphical interfaces theoretical investigations and physical implementation strategies. Categories and Subject Descriptors Information Systems General Database Management Logical Design data models Database Management Physical Design access methods Database Management Languages data description languages DDL data manipulation .