Abstract
Having emerged as a standard web language, XML has become the core of e-business solution. XML is a semistructured data that is represented as graph, which is a distinctive feature compared to other data dealt withexisting database. And query is represented as regular path expression, which is evaluated by traversing each node of the graph. In XML document withDTD, the DTD may be able to provide many valuable hints on query optimization, because it has information on the structure of the document. Using signature and information from DTD, we can minimize the traverse of nodes and quickly execute the XML query of regular pathexpression fast.