An introduction to and overview of object-oriented database systems, providing in-depth analysis of the technology and current advances in the field. Readers will gain insight into OODBMS concepts such as persistence, object-identity, transaction mechanisms and support for composite objects and will learn how to implement their own OODBMS. The book also covers the latest developments in this new database technology; examples of three commercial OODBMS: ODI/ObjectStore, Objectivity/DB and Versant; a survey of other available commercial OODBMS; OODBMS evaluation techniques; market trends and a description of products offered by various vendors.