METHOD AND SYSTEM FOR MULTIVERSION PARALLEL CONTROL OVER OBJECT-ORIENTED DATA BASE

摘要

PURPOSE:To enables a read-only transaction to read a new version. CONSTITUTION:A commit list comparison part 1 and an updata object number inspection part 2 shifts a set (VSr) of versions which the read-only transaction accesses to a set (VSu) of versions to be comitted newly by a version set transition part 6 when there are objects having the same versions belonging to the set (VSr) that the read-only transaction accesses and the set (VSu) of versions comitted by an update transaction, a version generated right after the version belonging to the VSr is a version belonging to the VSu as to an object having a different version, and a readout list comparison part 5 finds that the version of the VSr that the read-only transaction should read as to objects having different version belonging to the VSr and VSu is not accessed.