| 摘要 |
A method, apparatus, and article of manufacture for executing a database query in a database management system. The method comprises the steps of generating a plurality of query plans for the database query, evaluating the plurality of query plans using a measured value for the resource metric, selecting a query plan from the evaluated query plans based on the measured resource metric, and executing the selected query plan. The apparatus comprises a query plan generator for generating a plurality of query plans, each query plan optimized with respect to at least one resource metric, and a query plan evaluator, communicatively coupled to a resource object and a database management system node, the evaluator selecting a query plan from the optimized query plan according to a measured resource metric obtained from the global resource object. The article of manufacture comprises a program storage device tangibly embodying one or more programs of instructions executable by the computer to perform the method steps of executing a database query in a database management system, the method steps comprising the method steps above.
|
