| 摘要 |
A method is disclosed for indexing and querying XML documents stored in a relational database. A user is allowed to choose columns of a database table for storing XML data of a known structure. The user has to input one or more XML paths for indexed data. Each path is stored in a static index table. In response to the input of the user defined paths, at least one dynamic index table is created for each static index table. The dynamic index table is updated upon data being entered into the database table. When a user's query is intercepted, any XML expression part of the query is processed and converted into one or more rows in the static index table. A new query is generated against the dynamic indexing tables, using the values obtained from the static index table, and executed. The user's query is then rewritten by transforming the XML path part of the user's query expression into a format understood by the database query engine. Finally, after the rewritten query is executed, the result is returned to the user, together with any non-XML part of the user's query, executed by the database query engine.
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