Regular Expressions in Xml Schema Evolution
نویسنده
چکیده
A data schema is a set of constructs that emulate relations between domain instances. Schema evolution is changes in the data schema and a system of data consistency support for such modifications. Axiomatic model regulates modifications and maintains data consistency by ensuring that the data schema always satisfies a set of axioms. This paper is an extension to previous work, which has defined an axiomatic model for XMLdatabase schema evolution. A DTD regular expressions mechanism is incorporated into the axiomatic model. A new classification of modifications allowable in the model is presented.
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