Patent ID: 7016915

Claim:
A method for processing XML queries over relational data and meta-data using a relational database system, comprising: parsing an input XML query over a default XML view into an internal representation of said query; presenting all non-meta-data references to said default XML view; identifying all meta-data references to said default XML view; substituting each of said non-meta-data references with direct references to relational database tables; replacing each of said meta-data references with a new reference to the internal representation of the default view over relational catalog tables, said new references including a higher-order operator ExecXQuery; optimizing said internal representation of said query; eliminating each ExecXQuery instance by recursively invoking said query processing on the inputs to ExecQuery begin executing the internal representation below ExecXQuery to convert said meta-data references to non-meta-data references; repeating said substituting for all former meta-data references; and returning XML query results.