METHOD FOR SET LOGICAL OPERATION IN LOGICAL RETRIEVAL AND RECORDING MEDIUM WHERE SET LOGICAL OPERATION PROGRAM IS RECORDED

摘要

PROBLEM TO BE SOLVED: To shorten the calculation time and to save memory resources by suppressing moduli of a set halfway in set logical operation for logical retrieval from a full-text data base, etc., using an index. ;SOLUTION: When the set logical operation is performed, the evaluation of specific operation for a complementary set, etc., is delayed until operation for the product of sets and a next complementary set appears and the evaluation (acquisition of operation result) of the operation which has been delayed is performed in combination with the operation for the product of sets and next complementary set. In the case of, for example, a combination of the delayed operation for the complementary set and the operation for the product of sets, the operation can perform conversion to a difference of the set to enable evaluation.;COPYRIGHT: (C)2000,JPO