Patent ID: 8108411

Claim:
A method comprising: sorting, via a computing device, a plurality of data sets including at least a first data set and a second data set, the first data set comprising at least one first data set key column storing a plurality of first records, the second data set comprising at least one second data set key column storing a plurality of second records, each key column comprises information identifying a location of each of the plurality of records within the respective data set, the location information for the first key column corresponds to a first position indicator that associates the first data set key column with the first data set and a second position indicator that associates the second data set key column with the second data set; identifying, via the computing device, a first record subset and a second record subset based on the respective key column, the first record subset comprising a first number of sorted first records and the second record subset comprising a second number of sorted second records; assembling, via the computing device, the first record subset and the second record subset into a working data set based in part on each of the key columns for the respective data sets and the respective number of sorted records in each respective record subset, wherein the respective number of sorted records in each record subset are based upon the other subset and capacity of the working data set, the working data set comprising the first record subset, the second record subset, a first last record indicator corresponding to a last record of the first record subset, and a second last record indicator corresponding to a last record of the second record subset; associating, via the computing device, each record in the working data set with a working data set position indicator, the working data set position indicator identifying the data set and the location within the data set from which the record was obtained, the working data set position indicator based on the first and second position indicators; and sorting, via the computing device, the working data set.