Extensible indexing: a framework for integrating domain-specific indexing schemes into Oracle8i

Extensible indexing is a SQL-based framework that allows users to define domain-specific indexing schemes, and integrate them into the Oracle8i server. Users register a new indexing scheme, the set of related operators, and additional properties through SQL data definition language extensions. The implementation for an indexing scheme is provided as a set of Oracle Data Cartridge Interface (ODCIIndex) routines for index-definition, index-maintenance, and index-scan operations. An index created using the new indexing scheme, referred to as domain index, behaves and performs analogous to those built natively by the database system. The Oracle8i server implicitly invokes user-supplied index implementation code when domain index operations are performed, and executes user-supplied index scan routines for efficient evaluation of domain-specific operators. This paper provides an overview of the framework and describes the steps needed to implement an indexing scheme. The paper also presents a case study of Oracle Cartridges (intermedia text, spatial, and visual information retrieval), and Daylight (Chemical compound searching) Cartridge, which have implemented new indexing schemes using this framework and discusses the benefits and limitations