| 摘要 |
Systems and programs for improving the efficiency of a sorting process in a computer system are disclosed. Data is provided in an input file external to the central processing unit of the computer system. In one embodiment, the implemented process involves investigating the contents of the input file in order to identify presorted portions thereof; incorporating the identified presorted portions of the input file into a second file external to the central processing unit, performing this step by rearranging directory information, without physically transferring the presorted portions from the input file. In sort processes involving both a string generation phase and a merge phase, the techniques described may be used in either or both phases, as well as in any output phase. Rearranging directory information rather than physically transferring data provides for greater efficiency in disk I/O. |
