Method and system for managing multiple database storage units

Abstract

The system manages at least a database in multiple database storage units, and the database is duplicated for redundancy. The system maintains the database redundancy for security. The system enables the maintenance and reorganization of the database storage units without interrupting the on-going operations involving the access to the database storage units. The non-stop ongoing database access is available by allocating a pair of a main storage unit and an intermediate storage unit that maintains the substantially identical data. During certain predetermined operations, the main storage unit is being dedicating to the on-going transactions while the intermediate database storage unit is manipulated to contain data that corresponds to a specified time. For example, the content of the intermediate storage is subsequently copied or used to update another database. When the above duplication or incorporation is completed, the intermediate storage unit is updated for the transactions that have taken place during the above operations to be synchronized with the main storage unit.

1 - 23 . (canceled) 
   
   
       24 . A method of archiving data, comprising the steps of:
 synchronizing second data in a second format with first data in a first format based upon system log data that is created as the first data is updated;   maintaining information management data for maintaining an update status as the second data is being synchronized with the first data; and   responding to an inquiry into the second data by merging information from the second data and the information management data.   
   
   
       25 . The method of archiving data according to  claim 24  wherein said synchronizing step is performed on a period between a first point when the second data was updated in a previous one of said synchronizing step was performed and a second point specified after the first point. 
   
   
       26 . The method of archiving data according to  claim 24  wherein the information management data is a combination of an update period, a time value and a geographical classification.