Date Added: Dec 2009
KeyWord Search (KWS) over relational data, where the answers are multiple tuples connected via joins, has received significant attention in the past decade. Numerous solutions have been proposed and many prototypes have been developed. Building on this rapid progress and on growing user needs, recently several RDBMS and Web companies as well as academic research groups have started to examine how to build industrial-strength keywords search systems. This task clearly requires addressing many issues, including robustness, accuracy, reliability, and privacy, among others. A major emerging issue, however, appears to be performance related: current KWS systems have unpredictable run time.