Patent ID: 8423507

Claim:
A method for managing replication of data between a master database managed by a master node and replica databases managed by a plurality of slave nodes connected to a tree structure having the master node as a root in a manner of having contents identical with that of the master database and which are used as search targets, the method comprising: the slave node, which has received a search instruction to search the data, transmitting to a parent node of the slave node a request for a transaction log up to the latest version related to an update of the master database, in a case of not receiving a reply message in a heart beat communication from the parent node within a predetermined time (Ts3) from the time of transmission of a request message in the heart beat communication to the parent node of the slave node; when the parent node which has received the request does not have the transaction log, the parent node which has received the request makes a request to its parent node for the transaction log, wherein the request is repeated to further parent nodes higher in the tree structure until a parent node having the transaction log is reached; the parent node, which has received the request and has the transaction log, transmits the transaction log to its child nodes, wherein the transmitting is repeated from each node to its child nodes until the slave node which has received the search instruction receives the transaction log; and the slave node updating the replica database by referring to the received transaction log.