Method for managing a database system
AssigneeHitachi, Ltd.
InventorsAkira Shimizu, Daisuke Ito
Life of this patent
Estimating the term…
Abstract
To provide a database which has plural log storage areas, and eliminates the sort in the restoration process by means of the application of logs, thereby carrying out the restoration quickly. A management server allocates DB servers to a corresponding one of plural data storage areas so as to access the corresponding one. The DB servers store data to the allocated data storage areas. When the data is referenced or updated, a log representing a data change history is stored in preset log areas for each data server. When the management server transmits a notification to change the data storage areas, area remapping logs are stored in log areas.
Claims20
A data processing system, comprising:
- a plurality of database servers that are connected with each other via a network;
- a plurality of data storage areas that store data of the database servers;
- and
- a management server that manages a correspondence between the database servers and the data storage areas, wherein:
- the management server comprises an area allocation management module that allocates the plurality of data storage areas to the plurality of database servers that have access to the data storage areas to be allocated, and notifies the database severs of the data storage areas to be allocated;
- the database server comprises:
- an area management module that holds the data storage area allocated to the database server itself by the area allocation management module;
- and
- a data processing module that stores data in the data storage area held by the area management module, refers to and updates the stored data, and, upon the update, stores a log indicating an update history of the data in a log area set respectively for the database servers in advance;
- and
- upon receiving a notification of a change of the allocation of the data storage area from the area allocation management module of the management server, the area management module stores an area remapping log indicating the change of the allocation of the data storage area in the log area.
A data processing system, comprising:
- a plurality of database servers that are connected with each other via a network;
- a plurality of data storage areas that store data of the database servers;
- and
- a management server that manages a correspondence between the database servers and the data storage areas, wherein:
- the management server comprises:
- an area allocation management module that allocates the plurality of data storage areas to the plurality of database servers that have access to the data storage areas to be allocated, and notifies the database severs of the data storage areas to be allocated;
- the database server comprises:
- an area management module that holds the data storage area allocated to the database server itself by the area allocation management module;
- and
- a data processing module that stores data in the data storage area held by the area management module, refers to and updates the stored data, and, upon the update, stores a log indicating an update history of the data in a log area set respectively for the database servers in advance;
- the log area set respectively for the database servers comprises a plurality of the log areas;
- and
- upon receiving a notification of a change of the allocation of the data storage area from the area allocation management module of the management server, the area management module changes the allocation of the data storage area.
A database managing method used for a database in which a plurality of database servers have access to a plurality of data storage areas allocated by a management server, comprising the steps of:
- causing the management server to allocate the plurality of data storage areas to the plurality of database servers that have access to the data storage area to be allocated;
- causing the database server to store data to the allocated data storage area, and to refer to and update the stored data;
- causing the database server to store a log indicating an update history of the data in a log area set in advance to the respective database severs upon the update;
- and
- causing the database server to store an area remapping log indicating a change of the allocation of the data storage area in the log area upon receiving a notification of the change of the allocation of the data storage area from the management server.
Dependencies are inferred from the claim text.