| 摘要 |
PROBLEM TO BE SOLVED: To secure work buffers whose number is the same as that of strings even unless a sufficiently large area exists by dividing a data block so as to execute an input even when a work area is small in a sort merge processing. SOLUTION: When the block is inputted in order of the keys in the leading record of the block in the buffers whose number is the same as that of the strings from the plural strings where the records arranged in key order are made into a block and recorded, an in-block input pointer 2 indicates the remaining record parts of the blocks which are divided and successively inputted when the largeness of the buffer is smaller than block length. Then, a block input means 1 successively inputs the remaining records of the block to the buffer which becomes vacant by the output of the recordes by the merge processing for outputting the inputted recordes to the buffer in key order based on the in-block input pointer 2. Thus, the movement and the input/output operation of the record is reduced so that the merge processing is efficiently executed. |
