| 摘要 |
Commonly searched nodes of complex data types contained in a collection of XML documents can be projected to, and their values can be stored in, corresponding columns in XML Table Index tables in a database system. In one embodiment, those columns stores logical pointers, rather than raw values, of the complex data types. Domain indexes are further provided to index at least one of the columns of complex data types in XML Table Indexes. The inclusion of complex data types and domain indexes provide a more efficient mechanism for searching domain specific data, such as audio, video, text stored in the collection of XML documents. Query optimizer logic of the database system can prepare one or more query execution plans for a submitted query including a plan that leverages XML Table Indexes and domain indexes and select a query execution plan based on cost information.
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