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Improving data quality in relational databases: Overcoming functional entanglements

Citation

Chen, T., Meyer, M., Ganapathi, N., Liu, S., & Cirella, J. (2011). Improving data quality in relational databases: Overcoming functional entanglements. (RTI Press Publication No. OP-0004-1105). Research Triangle Park, NC: RTI Press. DOI: 10.3768/rtipress.2011.op.0004.1105

Abstract

The traditional vertical decomposition methods in relational database normalization fail to prevent common data anomalies. Although a database may be highly normalized, the quality of the data stored in this database may still deteriorate because of potential data anomalies. In this paper, we first discuss why practitioners need to further improve their databases after they apply the traditional normalization methods, because of the existence of functional entanglement, a phenomenon we defined. We outline two methods for identifying functional entanglements in a normalized database as the first step toward data quality improvement. We then analyze several practical methods for preventing common data anomalies by eliminating and restricting the effects of functional entanglements. The goal of this paper is to reveal shortcomings of the traditional database normalization methods with respect to the prevention of common data anomalies, and offer practitioners useful techniques for improving data quality.

Author Details

Tennyson Chen

Tennyson X. Chen, MS, is a senior research analyst and software system architect in RTI International’s Research Computing Division. His main focus is the National Survey of Drug Use and Health (NSDUH) project, for which he is a key system designer and database manager.

Martin Meyer

Martin D. Meyer, PhD, is a senior system architect and database manager in RTI International’s Research Computing Division. He is the NSDUH data processing manager.

Nanthini Ganapathi

Nanthini Ganapathi, MS, is a senior web developer and a NSDUH database designer at RTI International.

Shuangquan Liu

Shuangquan (Sean) Liu, PhD, is a senior software developer and a NSDUH database designer at RTI International.

Jonathan Cirella

A software developer and database practitioner in RTI International’s Research Computing Division, Jonathan M. Cirella, BS, designs and maintains application databases for the National Survey of Drug Use and Health (NSDUH) project.