Mapping Data to Queries : Semantics of the ISA Rule

In many application scenarios, diverse data sources produce XML messages with similar data but varying schemas. In result, data integration systems for XML data are in high demand. The technique presented in this technical report uses mapping rules to integrate diverse XML data. The introduced Is-a Rule enables a polymorphic usage of XML data items. Underlying XQuery programs operate on one main schema only while original data is not transformed, duplicated, or deleted. Techniques are shown that ensure scalability to large numbers of rules and data. Through appending additional rules, the data integration process is extensible in a pay-as-you-go-along fashion.