| 摘要 |
PURPOSE:To improve the degree of freedom of retrieval by storing retrieval information and comparing the information read out from a data base with the retrieval information about the whole data. CONSTITUTION:When plural key words are set up and a document including (x) pieces of a certain key word and >=(y) pieces of other key words is to be extracted, the numbers (x), (y) are stored in a memory. The kind of retrieval to be executed is decided by operating a selector. The key words are stored in memories QM1-QMn. Information read out by an external storage device DM1 is compared with the key words by comparators MMC1-MMCn. When these values coincide with each other, the number of times of coincidence is counted. When retrieval for one record has been completed, the succeeding record is continued to be retrieved. Whether the number of times of coincidence satisfies conditions (x), (y) or not is judged and the corresponding record address is extracted. |
