DISTRIBUTED DATABASE SYSTEM, FIRST DATABASE DEVICE OF DISTRIBUTED DATABASE SYSTEM, SECOND DATABASE DEVICE OF DISTRIBUTED DATABASE SYSTEM AND COMPUTER PROGRAM

摘要

PROBLEM TO BE SOLVED: To secure consistency between data managed by a distributed database system and data managed by a distribution destination node even during restoration from a failure in the distributed database system.SOLUTION: A first database device 11 transmits a mastering instruction to a second database device 12 (S207), and also transmits a data update telegram induction response telegram to a transmission source node 2 (S208) if the first database device cannot receive a cache data update response telegram (S206) due to network disconnection or the like between the first database device 11 and a distribution destination node 3. When receiving the data update telegram induction response telegram, the transmission source node 2 transmits a data update request telegram to the second database device 12 (S210). When the second database device 12 receives the mastering instruction, and receives a retransmitted data update request telegram, the second database device 12 transmits a cache data update request telegram to the distribution destination node 3 (S212).