| 摘要 |
PROBLEM TO BE SOLVED: To achieve the high speed synchronization of a database by selecting and executing a suitable achievement method from two replication achievement methods.SOLUTION: Storage means stores changed page information including the number of changed pages, first processing means performs the processing of a query in a complier layer, and makes storage means store the query, second processing means performs the processing of a query in a pager layer, and makes the storage means store the changed page information, first execution means transmits a query for reflecting the change of a master DB on a replica DB to a duplication DB on the basis of the stored query, second execution means transmits the data of the changed page to the duplication DB on the basis of the changed page information, and determination means determines which of the first execution means and the second execution means should synchronize the replica DB with the master DB on the basis of the number of changed pages and a predetermined value. |
