10. The method of claim 1 , wherein determining one or more frequently used multi joins in the workload comprises: building a data structure to record join relationship and one or more usage patterns; using the data structure to find a list of one or more commonly used multi-joins; and sorting all multi joins by defined order criteria.
10. The method of claim 1 , wherein determining one or more frequently used multi joins in the workload comprises: building a data structure to record join relationship and one or more usage patterns; using the data structure to find a list of one or more commonly used multi-joins; and sorting all multi joins by defined order criteria. 11. The method of claim 10 , wherein the data structure comprises a matrix.