On reducing redundancy and improving efficiency of XML labeling schemes

ABSTRACT

The basic relationships to be determined in XML query processing are ancestor-descendant (A-D), parent-child (P-C), sibling and ordering relationships. The containment labeling scheme can determine the A-D, P-C and ordering relationships fast, but it is very expensive in determining the sibling relationship. The prefix labeling scheme can determine all the four basic relationships fast if the XML tree is shallow. However, if the XML tree is deep, the prefix scheme is inefficient since the prefix is long. Furthermore, the prefix label is repeated by all the siblings (only the self labels of these siblings are different). Thus in this paper, we propose the P-Containment and P-Prefix schemes which can determine all the four basic relationships faster no matter what the XML structure is; meanwhile P-Prefix can reduce the redundancies in the prefix labeling scheme.

REFERENCES

• 1: C. Li and T.W. Ling. On Reducing Redundancy and Improving Efficiency of Labeling Schemes (long version of this paper). Available from the author, 2005.
• 2: Igor Tatarinov , Stratis D. Viglas , Kevin Beyer , Jayavel Shanmugasundaram , Eugene Shekita , Chun Zhang, Storing and querying ordered XML using a relational database system, Proceedings of the 2002 ACM SIGMOD international conference on Management of data, June 03-06, 2002, Madison, Wisconsin [doi>10.1145/564691.564715]
• 3: Chun Zhang , Jeffrey Naughton , David DeWitt , Qiong Luo , Guy Lohman, On supporting containment queries in relational database management systems, Proceedings of the 2001 ACM SIGMOD international conference on Management of data, p.425-436, May 21-24, 2001, Santa Barbara, California, United States

INDEX TERMS

Primary Classification:
  H. Information Systems
  H.2 DATABASE MANAGEMENT
      H.2.4 Systems
          Subjects: Query processing

General Terms:
Performance

Keywords:
XML, labeling scheme, query, redundancy