Rewriting of Visibly Pushdown Languages for XML Data Integration
Source: University of Victoria
In this paper, the authors focus on XML data integration by studying rewritings of XML target schemas in terms of source schemas. Rewriting is very important in data integration systems where the system is asked to find and assemble XML documents from the data sources and produce documents which satisfy a target schema. As schema representation, they consider Visibly Pushdown Automata (VPAs) which accept Visibly Pushdown Languages (VPLs). The latter have been shown to coincide with the family of (word-encoded) regular tree languages which are the basis of formalisms for specifying XML schemas.