A semantic network-based design methodology for XML documents

Abstract

The eXtensible Markup Language (XML) is fast emerging as the dominant standard for describing and interchanging data among various systems and databases on the Internet. It offers the Document Type Definition (DTD) as a formalism for defining the syntax and structure of XML documents. The XML Schema definition language, as a replacement for the DTD, provides more rich facilities for defining and constraining the content of XML documents. However, it does not concentrate on the semantics that underlies these documents, representing a logical data model rather than a conceptual model. To enable efficient business application development in large-scale electronic commerce environments, it is necessary to describe and model real-world data semantics and their complex interrelationships. In this article, we describe a design methodology for XML documents. The aim is to enforce XML conceptual modeling power and bridge the gap between software development and XML document structures. The proposed methodology is comprised of two design levels: the semantic level and the schema level. The first level is based on a semantic network, which provides semantic modeling of XML through four major components: a set of atomic and complex nodes, representing real-world objects; a set of directed edges, representing semantic relationships between the objects; a set of labels denoting different types of semantic relationships, including aggregation, generalization, association, and of-property relationships; and finally a set of constraints defined over nodes and edges to constrain semantic relationships and object domains. The other level of the proposed methodology is concerned with detailed XML schema design, including element/attribute declarations and simple/complex type definitions. The mapping between the two design levels is proposed to transform the XML semantic model into the XML Schema, based on which XML documents can be systematically created, managed, and validated.

References

1. Beeri, C. and Tzaban, Y. 1999. SAL: An algebra for semistructured data and XML. In Proceedings of the International Conference on the Web and Databases (Pennsylvania), 37--42.]]
2. Booch, G., Jacobson, L., and Rumbaugh, J. 1998. The Unified Modeling Languages User Guide. Addison-Wesley, Reading, Mass.]]
3. Bradley, N. 1998. The XML Companion. Addison-Wesley, Reading, Mass.]]
4. Bryan, M. 1992. An introduction to the standard generalization markup language (SGML). Available at http://www.personal.u-net.com/ sgml/sgml.htm.]]
5. Buneman, P., Dacidson, S., Hillebrand, G., and Suciu, D. 1996. A query language and optimization techniques for unstructured data. In Proceedings of the ACM SIGMOD International Conference on Management of Data (Montreal).]]
6. Buneman, P., Fan, W., Simeon, J., and Weinstein, S. 2001. Constraints for semi-structured data and XML. SIGMOD Record 30, 1 (March), 47--54.]]
7. Conrad, R., Scheffner, D., and Freytag, J. 2000. XML conceptual modeling using UML. In Proceedings of the International Conference on Conceptual Modeling, 558--571.]]
8. Consortium, W. W. W. 2000a. Extensible markup language (XML) 1.0. Available at http://www.w3.org/ TR/REC-xml]]
9. Consortium, W. W. W. 2000b. Resource description framework (RDF) schema specification 1.0. Available at http://www.w3.org/TR/2000/CR-rdf-schema-20000327/.]]
10. Consortium, W. W. W. 2000c. The XML data model. Available at http://www.w3.org/XML/ Datamodel.html/.]]
11. Consortium, W. W. W. 2000d. XML linking language (XLink) 1.0. Available at http://www.w3.org/TR/xlink/.]]
12. Consortium, W. W. W. 2001. XML Schema Part 0: Primer. Available at http://www.w3.org/TR/ xmlschema-0/.]]
13. Dillon, T. and Tan, P. 1993. Object Oriented Conceptual Models. Prentice-Hall, Englewood Cliffs, N.J.]]
14. Goldman, R. and Widom, J. 1997. Dataguides: Enabling query formulation and optimization in semistructured databases. In Proceedings of the 23rd International Conference on Very Large Data Bases (Athens), 436--445.]]
15. Goldman, R., McHugh, J., and Widom, J. 1999. From semistructured data to XML: Migrating the Lore data model and query language. In Proceedings of the International Conference on the Web and Databases (Pennsylvania), 25--30.]]
16. Morgado, E. 1986. Semantic networks as abstract data types. PhD Thesis, Tech. Rep. 86-1, Department of Computer Science, SUNY at Buffalo, NY.]]
17. Rahayu, W., Chang, E., Dillon, T., and Taniar, D. 1996. Aggregation versus association in object modelling and databases. In Proceedings of the Seventh Australasian Conference on Information Systems (Australia).]]
18. Sahuguet, A. 2000. Everything you ever wanted to know about DTDs, but were afraid to ask. In Proceedings of the International Conference on the Web and Databases (Texas), 69--74.]]
19. Shapiro, S. 1991. Cables, paths, and subconscious reasoning in propositional semantic networks (chapter). In Principles of Semantic Networks---Explorations in the Representation of Knowledge, J. F. Sowa, Ed.]]
20. Xiao, R., Dillon, T., Chang, E., and Feng, L. 2001a. Mapping object relationships into XML schema. In Proceedings of the International Conference on OOPSLA Workshop on Objects, XML and Databases.]]
21. Xiao, R., Dillon, T., Chang, E., and Feng, L. 2001b. Modeling and transformation of object-oriented conceptual models into XML schema. In Proceedings of the International Conference on Database and Expert Systems Applications (Munich), 795--804.]]

Index Terms

• Applied computing

  • Document management and text processing

    • Document preparation

• Computing methodologies

  • Artificial intelligence

    • Knowledge representation and reasoning

      • Semantic networks

• Information systems

  • Data management systems

    • Database design and models

      • Data model extensions