Integrating SQL Databases with Content-Specific Search Engines

In recent years, database research and product development activities have focused on support for non-traditional data types, such as text or multi-media documents. This paper describes an approach of coupling SQL databases and content-specific search engines, such as fulltext retrieval engines, in an efficient manner. It is based on a query rewrite scheme that exploits so-called table functions, which are used to pass results from external search engines into the database engine. Using this approach the content-specific indexing mechanisms of search engines can be exploited without having to extend the database engine with new access methods, or having to break up the search engine to map its indexing scheme to database index structures.