METHOD OF TRANSITIVE CLOSURE, METHOD OF COMPRESSING DATA BASE, METHOD AND SYSTEM FOR DATA BASE STORAGE, METHOD OF PRODUCING DATA BASE AND INFORMATION SUPPLY SYSTEM

摘要

PURPOSE: To reduce the number of access to a secondary storage medium by dividing a data base into appropriate segments to be settled inside the memory of a processor and efficiently considering all nodes in a graph in the calculation of transitive closure. CONSTITUTION: An initial data base 100 is sorted relating to a source node first and then sorted relating to a destination node, one division part of the sorted data base is transferred to the processor 200 and information is processed within the range of the division part. Respective links remaining inside the data base 100 are delivered to the processor 200, influence on a pivot node for the transferred division part is taken into consideration and a transitive link is generated when it is required. The division part is written back to the data base 100, the next division part is transferred from the data base 100 to the processor 200 and the procedure is repeated. Thus, the access to the secondary storage medium is minimized.