Departmental Papers (CIS)

Date of this Version

March 2003

Document Type

Conference Paper


Copyright 2003 IEEE. Reprinted from Proceedings of the 19th International Conference on Data Engineering 2003 (ICDE 2003), pages 543-554.

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We present a technique for refining the design of relational storage for XML data based on XML key propagation. Three algorithms are presented: one checks whether a given functional dependency is propagated from XML keys via a predefined view; the others compute a minimum cover for all functional dependencies on a universal relation given XML keys. Experimental results show that these algorithms are efficient in practice. We also investigate the complexity of propagating other XML constraints to relations, and the effect of increasing the power of the transformation language. Computing XML key propagation is a first step toward establishing a connection between XML data and its relational representation at the semantic level.



Date Posted: 07 May 2005