DATABASE MANAGEMENT SYSTEM, DATABASE MANAGEMENT METHOD, DATABASE MANAGEMENT PROGRAM AND LOCK ESCALATION CONTROL DEVICE

摘要

PROBLEM TO BE SOLVED: To properly control activation of a lock escalation.SOLUTION: A lock control part checks whether a write-in objective storage area in transaction processing is locked and locks the write-in objective storage area when it is not locked, while the lock control part compares the number of locks per transaction with a threshold per a monitoring objective storage area and raises a hierarchy of lock in the monitoring objective storage area when the number of locks exceeds the threshold. A data processing part writes data required by the transaction which is a lock origin in the write-in objective storage area locked by the lock control part. A threshold change part changes the threshold used by the lock control part for raising the hierarchy of lock, on the basis of gain information including an execution status of the transaction per monitoring objective storage area.SELECTED DRAWING: Figure 1