The new SQL 3 standard has resulted in an upsurge of object-relational databases. This book gives a brief outline of relational and object-oriented databases, providing a framework in which to explain the new design and implementation issues involved in object-relational database systems. The presentation is illustrated with examples from Oracle 8. This book will give readers a sound grasp of the theoretical background and a clear idea of the many practical applications of an object-relational database system.