XMLTable Index - An Efficient Way of Indexing and Querying XML Property Data

摘要

Efficiently storing and querying XML has been widely studied in research and industrial settings. Major RDBMS vendors now support XML as a native datatype in their systems and provide physical means of storing schema agnostic XML data. Typically this data is stored in CLOBs, BLOBs, or tree forms, with path or value indices used to efficiently process XQuery and SQL queries. However, in many use case queries derived from industrial XML applications, we find that it is very common to query XML based on a group of related property data and to query on the master-detail relationships using the SQL XMLTable construct. We propose an indexing mechanism called the XMLTable Index which is more efficient than the path and value index approach for this class of queries, and provides a way to efficiently process these queries over any physical XML storage form. The XMLTable Index complements the path/value index approach, and can be enhanced in its capabilities by using it in conjunction with path, value, text and other domain indices.