Abstract: The present invention discloses a data processing system in which system data is divided and stored in the plurality of output files. In the data processing system, a maximum capacity of data is set corresponding to each of a plurality of output files in accordance with information from an external unit. It is judged whether a total volume of data stored in a current output file, which is one of the plurality of output files, reaches said maximum capacity corresponding to the current output file when data is processed and stored in the current output file. Moreover, the current output file is switched to another of the plurality of output files when the total volume of data stored in the current output file reaches the maximum capacity corresponding to the current output file.

Abstract: A sort/merge processor which processes, with a single command, a heterogeneous collection of input files that require different processing options. Input data files are divided into groups each of which shares a common record extraction criterion, a common record reformatting rule, and common file system. A group profile identification unit accepts a sort/merge command and identifies such rules and criteria for the individual file groups by parsing group profile specifications contained in the command. Each time a specific input file group is given, a suitable processing environment is set up by an extraction criteria setting unit, a reformatting rule setting unit, and a file system setting unit. A file reading unit reads out records from input files through the specified file system. Then a record extraction processor extracts relevant records on the basis of the record extraction criterion, and a record reformatting processor reformats them according to the record reformatting rule.

Abstract: The object is to improve data compression efficiency and to save disc space during a sort-merge operation.