OBJECTS THROUGH RELATIONS The ADOORE Approach Michal Kopecky and Jaroslav Pokorny Department of Software Engineering Faculty of Mathematics and Physics Charles University Malostranske mim. 25 118 00 Praha 1, Czech Republic e-mail: pokorny@ksi.ms.mff.cuni.cz kopecky@ksi.ms.mff.cuni.cz 1. INTRODUCTION 1 * Object databases are usually referring to those data management products that are specifically designed for use with an object programming language and are very closely coupled with one or more object programming languages. Typically, the most of the re- cent OODBMSs use c++ and/or Small talk languages as their database programming lan- guage. The application programmer may access database objects directly using the database operations in the programming language, or may perform associative lookups of objects using the query language. Unfortunately, the latter includes many problems con- cerning both the design of such languages and their implementation. Two significant de- velopment lines are recently at disposal: ODMG-93 standard with its language OQL [Ca93] and the work proposed by the ANSI X3H2 group well-known as SQL3 [Me94] that stores objects in special kinds of columns in relations. On the other hand, Dr. Mary Loomis mentions in her interview in DBMS Journal [Ka94] that the typical C++ programmer who is not a database person, is not familiar with SQL, and is not familiar with relational systems, would like to deal with the objects space as a very large extended virtual memory of objects. A care whether the objects are in main memory, on disk, or across the network is superfluous for him/her. Programmers do not want to have to think whether an object is in the cache or it is necessary to get it from disk. Similarly, they do not want to learn new languages as OQL or SQL, for example. * This work has been supported by COPERNICUS project ADOORE (CPP94-00764). Systems Development Methods for the Next Century edited by Wojtkowski et al. Plenum Press, New York, 1997