Patent ID: 6549920
Filing Date: 2003-04-15
Classification: G06F,Y10S

Abstract:
A data duplication control method for a system which includes a main system having a first processor system in which a first DBMS operates and a first storage subsystem connected to said first processor system and a subordinate system having a second processor system in which a second Database Management System (DBMS) operates and a second storage subsystem connected to said second processor system, with said first and second storage subsystem being connected to each other, said method comprising:a step, which is implemented by said first DBMS by being directed by said first processor system, of overwriting database table data (will be termed â€œDB table dataâ€ ) which is stored in a cache and put in and out by said first DBMS to the database table (will be termed â€œDB tableâ€ ) of said first storage subsystem, and holding the updating of the DB table data in the DB table against a subsequent request of updating of the DB table data; and a step, which is implemented by said first storage subsystem by being directed by said first processor system, of transferring the DB table data in the DB table of the self storage subsystem to the DB table of said second storage subsystem thereby to duplicate the DB table data, and suspending the subsequent transfer of DB table data so that the DB tables of said first and second storage subsystems are in a matched state, thereby enabling said second DBMS to refer the copied DB table in a matched state.