摘要:
A database recovery method including a computer and a storage system, in which: the storage system includes a disk drive for storing data; the disk drive includes a data volume, a snapshot volume, a database log for storing an update log, and an update journal for storing update information of the data volume; a recovery point for indicating an end point of a range to which the update journal is to be applied and a starting point of a range to which the database log is to be applied is recorded to recover the data volume; and when the database is to be recovered, the update journal is applied to the snapshot volume up to the recovery point, the snapshot volume after the update is switched to the data volume, and the database log after the recovery point is applied to the data volume that is set by switching.
摘要:
Provided is a database processing system including: a computer for outputting data in response to a received query request; and a storage system including a storage device for storing the data, in which: the storage device stores a plurality of partial indices indicating a storage location of the data; the data stored in the storage device is grouped; and the computer is configured to: receive the query request for the data; acquire one of the plurality of partial indices; specify, based on the query request for the data and the acquired one of the plurality of partial indices, a location at which the requested data is stored; and send a request to acquire the data stored at the specified location to the storage system. Accordingly, in the database processing system, a time period necessary to input and output the data is shortened.
摘要:
A technique capable of constructing a disaster recovery system reduced in performance degradation of a primary system is provided. The technique includes a step of conducting synchronous writing of log information into a secondary storage subsystem in a secondary system when a write request received from a host computer is a write request of log information, a step of temporarily storing a write request and conducting asynchronous writing into the secondary storage subsystem when the received write request is a write request of database data or status information, a step of modifying log information, data in a database area, and status information in the secondary storage subsystem according to contents of a write request received from a primary storage subsystem, and a step of recovering the database area according to contents of log information in a location indicated by the status information.
摘要:
To guarantee that contents of an update by a transaction in a parallel database management system. A database management system includes a replica database management unit that manages the replica database, records synchronous information at a timing at which one of the transaction generated is valid in every database management unit and other transactions are invalid in every database management unit, extracts update information and the synchronous information for creating the replica database from the update logs, and causes the replica database management unit to import the update information of each transaction that has become valid before the synchronous information was recorded.
摘要:
A database access management unit manages accesses to databases managed by a plurality of data processing servers each provided for each data kind. A request analysis unit analyzes a request from an application containing a process request for each data kind. A process server selection unit selects the data processing server for executing a data process in accordance with the data kind. A data process request unit requests the data processing server to execute the data process. A process result edition unit edits the process result by the data processing server.
摘要:
A technology for verifying backup data capable of synchronizing timings of checksum calculation and verifying data consistency regardless of the storing position of the data is provided. In a backup system using a data update log, a checksum of data of a backup source and a checksum of backup data are checked, thereby verifying data consistency. Data check log generation means and the like are provided so that the data update log and the data check log are transmitted in order to a secondary site. By this means, the timings of the checksum calculation are synchronized. Further, by providing data area extraction means and the like, the verification of data consistency can be performed regardless of the storing position of the data.
摘要:
The present invention is constituted so as to enable the recovery of a database even when a log comprising a DB update history is not created. When executing a transaction in the logless mode, a logless-start log is created and written to a primary log VOL 55A at the start of this transaction, and this logless-start log is also written to a secondary log VOL 55B. Thereafter, batch processing is carried out for a DB of a primary DB VOL 51A, and while this transaction is being executed, the pair-split state of the DB VOL is cancelled either prior to the start or after the end of the batch processing, and if the difference between the DB VOLs is eliminated subsequent to the end of batch processing, a logless-end log is created and written to the primary log VOL 55A, and this log is also written to the secondary log VOL 55B.
摘要:
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.
摘要:
A data processing system is used which is provided with a computer for executing a program, and a storage unit having a cache memory for storing data transmitted as a result of execution of the program and a disk device for storing data stored in the cache memory. The storage unit responds to an input of a request for storing data transmitted from the program to store the transmitted data in the cache memory. Next, the storage unit responds to an input of a request for flashing transmitted from the program to store, in the disk device, the data stored in the cache memory.
摘要:
A data processing apparatus includes a storage device having a replication generation function for replicating a data base to create a replication data base, and stores data and a plurality of log information in transaction processing that uses the data in the storage device, selects a transaction that is performing a data operation without meeting a predetermined condition after synchronization between the data base and the replication data base is released, and performs the data operation cancellation processing to the replication data base by the selected transaction. It also selects a transaction, which meets the predetermined condition and is not performing a data operation to the replication data base, to perform a data operation to the replication data base with the selected transaction. It then becomes possible to reduce the burden for the data processing apparatus during using the replication data base.