Making Database Schema Hierarchical for Visual Access to Databases

摘要

Making the database schema hierarchical can help a casual user retrieve information from a complex database. The hierarchical database schema provides further insight into database content and focuses on meaningful data by a top-down method. The user can proceed with a hierarchical visual query, which ultimately simplifies the query, reduces the syntax error rate and conserves the query time. In this paper, we present a hierarchical graph which makes the database schema hierarchical, naturally integrates the browsing and querying and, consequently, allows the user to proceed with an incremental query on the hierarchical database schema. Also proven herein are the existence, uniformity, and consistency of the hierarchical graph to verify that the graph can be used to query the database. This paper also discusses the semantics of high-level nodes and conducts an experiment to evaluate users’ performance. Finally, we describe how one can use the hierarchical graph to unify the tasks of making the schema hierarchical, creating concept hierarchies, and integrating the databases.