| 摘要 |
PURPOSE:To shorten the retrieval time of a control table to process effectively items of many attributes, by converting the index key part in an index file to an internal code of a single attribute. CONSTITUTION:Index keys of plural items described in code systems different in attribute are inputted to a register 3 for input index key. Key parts of index records are converted to an internal code system of a single attribute and are stored in an index file 2'. In retrieval, input index keys inputted to the register 3 are converted to the internal code system by a converting means 6, and a binary single item index is set to a register 3'. The output of this register 3' is applied to a retrieving means 4' to retrieve an internal code of the single attribute stored in the file 2', and it is outputted to a reading means 5. Thus, the retrieval time of the internal code is shortened to improve the processing effect for items of many attributes. |
