Declarative XML Data Cleaning with XClean

Data cleaning is the process of correcting anomalies in a data source, that may for instance be due to typographical errors, or duplicate representations of an entity. It is a crucial task in customer relationship management, data mining, and data integration. With the growing amount of XML data, approaches to effectively and efficiently clean XML are needed, an issue not addressed by existing data cleaning systems that mostly specialize on relational data. We present XClean, a data cleaning framework specifically geared towards cleaning XML data. XClean’s approach is based on a set of cleaning operators, whose semantics is well-defined in terms of XML algebraic operators. Users may specify cleaning programs by combining operators by means of a declarative XClean/PL program, which is then compiled into XQuery. We describe XClean’s operators, language, and compilation approach, and validate its effectiveness through a series of case studies.