COKES: Continuous Top-k Keyword Search in Relational Databases

Abstract

Keyword search in relational databases has been widely studied in recent years. Most of existing methods focus on answering snapshot keyword queries in static databases. However, in practice, relational databases are always being updated continually. Reevaluating a keyword query using existing methods after the database is updated is prohibitively expensive. In this paper we describe the COKES system, which keeps the set of answers whose upper bounds of future relevance scores are larger than a threshold for top-k answers maintenance. Experimental results show that the proposed method is efficient in answering continuous top-k keyword queries in relational databases.