A Signature Access Method for the Starburst Database System

This paper describes a new signature generation method for constructing multi-level signature files to support both relational queries which contain multiple conjunctive (AND) predicates and generic document text queries. We describe the major problems with traditional multi-level signature files and then describe how to build multi-level signature files using a new composite method of parent signature generation. Performance of this signature generation scheme improves as more key fields are provided in the query. A combinatorial error problem common to all multilevel signature structures is identified and addressed. We show how a signature access method can provide query support for a large number of fields in a relation for which no index exists and can dramatically reduce the number, of relation tuples that must be accessed during a normal scan. If one or more fields of the relation contain long tield data such as text, the same signature mechanism can also provide query support for text search predicates.