QRelX: generating meaningful queries that provide cardinality assurance

In many business and consumer applications, queries have cardinality constraints. However, current database systems provide minimal support for cardinality assurance. Consequently, users must adopt a cumbersome trial-and-error approach to find queries that are close to the original query but also attain the desired cardinality. In this demonstration, we present QRelX a novel framework to automatically generate alternate queries that meet the cardinality and closeness criteria. QRelX employs an innovative query space transformation strategy, proximity-based search and incremental cardinality estimation to efficiently find alternate queries. Our demonstration is an interactive game that allows the audience to compete with QRelX via manual query refinement. We illustrate the importance of cardinality assurance through real-time comparisons between manual refinement and QRelX. We also highlight the novelty of our solution by visualizing the core algorithms of QRelX.