ABSTRACT
Relational database systems (RDBS) originated from the IBM R project in the 1970s and gained great popularity in business applications. As of today, RDBS products are still the dominant choice of database systems for information management problems. However, with the advancement of computer software and hardware, several limitations of RDBS products began to attract a lot of attention in the late 1980s. First, structured query language (SQL)-92 only supports numbers and strings, but several applications began to include complex data objects such as geographic points, images, and digital signal data. Second, relational tables are flat and do not support nested structures efficiently. Third, RDBS do not take advantage of object-oriented (OO) approaches, which have been widely accepted in industry software engineering practices. This chapter introduces some improvements and advancements made to RDBS, specifically OODBMS and object RDBMS (ORDBMS).
