Efficient order dependency detection
- 490 Downloads
Order dependencies (ODs) describe a relationship of order between lists of attributes in a relational table. ODs can help to understand the semantics of datasets and the applications producing them. They have applications in the field of query optimization by suggesting query rewrites. Also, the existence of an OD in a table can provide hints on which integrity constraints are valid for the domain of the data at hand. This work is the first to describe the discovery problem for order dependencies in a principled manner by characterizing the search space, developing and proving pruning rules, and presenting the algorithm Order, which finds all order dependencies in a given table. Order traverses the lattice of permutations of attributes in a level-wise bottom-up manner. In a comprehensive evaluation, we show that it is efficient even for various large datasets.
KeywordsData profiling Functional dependencies Metadata
We thank Ziawasch Abedjan for his numerous helpful comments, which improved this work.
- 2.Abedjan, Ziawasch, Naumann, Felix: Advancing the discovery of unique column combinations. In: Proceedings of the International Conference on Information and Knowledge Management (CIKM), pp. 1565–1570, (2011)Google Scholar
- 3.Agrawal, R., Srikant, R.: Fast algorithms for mining association rules in large databases. In: Proceedings of the International Conference on Very Large Databases (VLDB), pp. 487–499, (1994)Google Scholar
- 5.Dong, J., Hull, R.: Applying approximate order dependency to reduce indexing space. In: Proceedings of the International Conference on Management of Data (SIGMOD), pp. 119–127, (1982)Google Scholar
- 11.Lichman, M.: UCI machine learning repository. University of California, Irvine, School of Information and Computer Sciences (2013). http://archive.ics.uci.edu/ml. Accessed March 10, 2015
- 15.Northwestern University. WikiTables: Public Site (2015). http://downey-n1.cs.northwestern.edu/public. Accessed March 10, 2015
- 18.Sloane, N.J.A.: The On-Line Encyclopedia of Integer Sequences—A000522 (2015). http://oeis.org/A000522. Accessed March 10, 2015
- 19.Szlichta, J., Godfrey, P., Gryz, J.: Chasing polarized order dependencies. In: Proceedings of the Alberto Mendelzon International Workshop on Foundations of Data Management (AMW), pp. 168–179, (2012)Google Scholar
- 21.Szlichta, J., Godfrey, P., Gryz, J., Ma, W., Qiu, W., Zuzarte, C.: Business-intelligence queries with order dependencies in DB2. In: Proceedings of the International Conference on Extending Database Technology (EDBT), pp. 750–761, (2014)Google Scholar