Patent ID: 6353818
Filing Date: 2002-03-05
Classification: G06F,Y10S

Abstract:
A method of executing a database query in a database management system, comprising the steps of:(a) generating a plurality of query plans for the database query, each query plan optimized with respect to at least one system resource metric of the database management system; (b) at run time, evaluating the plurality of query plans using a measured value for the system resource metric; (c) selecting a query plan from the evaluated plurality of query plans based on the measured value; and (d) executing the selected query plan in the database management system; predicting at least one resource requirement for the query; generating a plurality of query plans for the database query, each query plan optimized with respect to at least one system resource metric of the database management system; at run time, evaluating the plurality of query plans using a measured value for the system resource metric; selecting a query plan from the evaluated plurality of query plans based on the measured value; executing the selected query plan in the database management system; when the predicted resource requirement exceeds a threshold value, and generating a query plan when the predicted resource requirement does not exceed the threshold value.