Abstract: A solution method of an in-doubt state in two-phase commit protocol of a distributed transaction system includes assigning a unique identifier to each log group, and registers information about a database management device having the management right of each log group in a first table, and rewriting the first table in such a way that another database management device may have a management right of a global representative log group when a management right of the global representative log group to the other database management device during an in-doubt state period of two-phase commit, and rewriting the first table in such a way that another database management device may have a management right of the global representative log group when a management right of a log group other than the global representative log group to another database management device during the in-doubt state period of two-phase commit.

Abstract: A database control method comprising a first main system processing in which, upon first data being stored in a second storage unit included in a second server communicably connected with the first server, the first data is stored in a first storage unit following instructions from a host computer, a first inhibiting processing in which, upon detecting an abnormality in communication with the second server, storing the first data in the first storage unit following instructions from a host computer is inhibited, a first query processing performing a first query to an arbitrating device arbitrating between the first server and the second server, and a processing executing or stopping the first main system processing in accordance with instructions from the arbitrating device.

Abstract: A control device 10 at a main center, in order for an update carried out in an operation database device M to be also conducted in an operation database device S at a sub-center, generates and transmits a differential log file 16 to a control device 20 at the sub-center. The control device 20 at the sub-center, when receiving a differential log file 22, updates the operation database device S on the basis of the log information in the differential log file 22, and accumulates the log information in a recovery log file 26. The log information of a recovery point set at the main center is incorporated into this recovery log file 26.

Abstract: A solution method of an in-doubt state in two-phase commit protocol of a distributed transaction system includes assigning a unique identifier to each log group, and registers information about a database management device having the management right of each log group in a first table, and rewriting the first table in such a way that another database management device may have a management right of a global representative log group when a management right of the global representative log group to the other database management device during an in-doubt state period of two-phase commit, and rewriting the first table in such a way that another database management device may have a management right of the global representative log group when a management right of a log group other than the global representative log group to another database management device during the in-doubt state period of two-phase commit.

Abstract: A control device 10 at a main center, in order for an update carried out in an operation database device M to be also conducted in an operation database device S at a sub-center, generates and transmits a differential log file 16 to a control device 20 at the sub-center. The control device 20 at the sub-center, when receiving a differential log file 22, updates the operation database device S on the basis of the log information in the differential log file 22, and accumulates the log information in a recovery log file 26. The log information of a recovery point set at the main center is incorporated into this recovery log file 26.