ENHANCED ABSTRACT-DATA-TYPES IN OBJECT-RELATIONAL DATABASES

The explosion in complex multimedia content makes it crucial for datab ase systems to support such data efficiently. This paper argues that t he ''blackbox'' ADTs used in current object-relational systems inhibit their performance, thereby limiting their use in emerging application s Instead, the next generation of object-relational database systems s hould be based on enhanced abstract data type (E-ADT) technology. An E -ADT can expose the semantics of its methods to the database system, t hereby permitting advanced query optimizations. Fundamental architectu ral changes are required to build a database system with E-ADTs; the a dded functionality should not compromise the modularity of data types and the extensibility of the type system. The imple mentation issues h ave been explored through the development of E-ADTs in Predator. Initi al performance results demonstrate an order of magnitude in performanc e improvements.