Database Research Group (CIS)

Document Type

Conference Paper

Date of this Version

April 1997


Copyright 1997 IEEE. Reprinted from Proceedings of the 13th International Conference on Data Engineering, April 1997, pages 55-65.

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The need to transform data between heterogeneous databases arises from a number of critical tasks in data management. These tasks are complicated by schema evolution in the underlying databases, and by the presence of non-standard database constraints. We describe a declarative language, WOL, for specifying such transformations, and its implementation in a system called Morphase. WOL is designed to allow transformations between the complex data structures which arise in object-oriented databases as well as in complex relational databases, and to allow for reasoning about the interactions between database transformations and constraints.



Date Posted: 04 June 2007

This document has been peer reviewed.