JOINT PROCESSING SYSTEM FOR DECENTRALIZED DATA BASE

摘要

PURPOSE:To improve the processing efficiency in a joint process by transmitting the number of tuples at the side having the smaller number of hash sorts with the hash packets at both sites according to the result of the hash sorting. CONSTITUTION:When a hash processing part 3 of a processor 1 is started, the tuples of the desired relation are read successively outpof a data base. These tuples are sorted to one of hash packets 11-0-11-p corresponding to the hash function valve of the prescribed join field value. then the number of tuples are informed to a short informing part 4. The part 4 transfers the number of tuples to a communication processing part 2 and an array comparison part 5. The part 5 receives the number of hash sorts from the site at the remote side and compares them with those at the own site. Then the part 5 transmits the tapples sorted to the packets even with the packet having a small number of hash sorts of the own site. The result of said comparison is sent to a joint processing part 6 for execution of the joint processing with the tuples received from the remote side for the packet whose joint processing should be applied at the own site.