Object-Oriented Database Development

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Object-Oriented Database Development
L E A R N I N G O B J E C T I V E S

After studying this chapter, you should be able to: ● Concisely define each of the following key terms: atomic literal, collection literal, set, bag, list, array, dictionary, structured literal, and extent. ● Create logical object-oriented database schemas using the object definition language (ODL). ● Transform conceptual UML class diagrams to logical ODL schemas by mapping classes (abstract and concrete), attributes, operations (abstract and concrete), association relationships (one-to-one, one-tomany, and many-to-many), and generalization relationships. ● Identify the type specifications for attributes, operation arguments, and operation returns. ● Create objects and specify attribute values for those objects. ● Understand the steps involved in implementing object-oriented databases. ● Understand the syntax and semantics of the object query language (OQL). ● Use OQL commands to formulate various types of queries. ● Gain an understanding of the types of applications to which object-oriented databases have been applied.

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n Chapter 14, we introduced you to object-oriented data modeling. You learned how to conceptually model a database using UML class diagrams. In this chapter, we will describe how such conceptual objectoriented models can be transformed into logical schemas that can be directly implemented using an object database management system (ODBMS). As you will learn later, although relational databases are effective for traditional business applications,

they have severe limitations (in the amount of programming required and DBMS performance) when it comes to storing and manipulating complex data and relationships. In this chapter, we will show how to implement applications within an object-oriented database environment. In Appendix D, you will learn about object-relational databases, which are the most popular way

References: Bertino, E., and L. Martino. 1993. Object-Oriented Database Systems: Concepts and Architectures. Wokingham, England: AddisonWesley. Cattell, R. G. G., D. Barry, D. Bartels, M. Berler, J. Eastman, S. Gamerman, D. Jordan, A. Springer, H. Strickland, and D. Wade. (Eds.) 2000. The Object Database Standard: ODMG 3.0. San Francisco: Morgan Kaufmann. Chaudhri, A. B., and R. Zicari. 2001. Succeeding with Object Databases. New York: Wiley. King, N. H. 1997. “Object DBMSs: Now or Never.” DBMS 10,7 (July): 42–99. Watterson, K. 1998. “When It Comes to Choosing a Database, the Object Is Value.” Datamation 44,1 (December–January): 100–107. Further Reading Leavitt Communications. 2003. “Whatever Happened to ObjectOriented Databases.” available at www.leavcom.com/ db_08_00 .htm. Atkinson, M, F. Bacnilhon, D. DeWitt, K. Dittich, D. Maier, and S. Zdonik. 1995. “The Object-Oriented Database System Manifesto.” available at http://www.cs.cmu.edu/People/ clamen/OODBMS/Manifesto/htManifesto/Manifesto.html. Web Resources relational” database management system (ORDBMS). The ORDBMS technology (see Appendix D) is compared with the relational databases from which ORDBMS is evolving and with the pure object databases that they will never replace. What challenges did you face in completing this task? www.cai.com/products/jasmine/analyst/idc/14821Eat.htm This bulletin discusses the changes and innovations currently shaping database technology and related products. It includes a summary of 1996 when a trend toward multimedia-type database product rollouts and a new extended version of relational database technology emerged that was dubbed the “object