PowerQ: An Interactive Keyword Search Engine for Aggregate Queries on Relational Databases
Zhong Zeng, Mong Li Lee, Tok Wang Ling · Movebank · 2016
Keyword search over relational databases has gained popularity due to its ease of use. Current research has focused on the efficient computation of results from multiple tuples, and largely ignores queries to retrieve statistical information from databases. The work in [5] developed a system that allows aggregate functions to be expressed using simple keywords. However, this system may return incorrect answers because it does not consider the semantics of objects and relationships in the database. In this paper, we present an interactive keyword search engine called PowerQ to answer queries involving aggregate functions and GROUPBY. PowerQ utilizes an ORM schema graph to capture the Object-Relationship-Attribute (ORA) semantics in the database. Given a keyword query, PowerQ identifies the various interpretations of the query and applies aggregate functions and GROUPBY on the appropriate attributes of objects/relationships. Each query interpretation is denoted as an annotated query pattern, whose meaning can be described in natural language to facilitate user understanding. Through user interactions, PowerQ can determine the user’s search intention, and translate the corresponding patterns into SQLs to compute the answers correctly. The PowerQ prototype is available at http://powerq.comp.nus.edu.sg.