Incremental Data Migration for Multi-database Systems Based on MySQL with Spider Storage Engine

Nowadays, with the spread of database systems and network systems in every field, a demand for sharing existent database systems grows. On the other hand, it is difficult to stop existent databases to reorganize into one large database system because database systems usually are mission-critical system. Thus, some kind of distributed database is necessary to solve this problem. The multi-database system is a kind of the distributed database system. It is a cluster of independent database systems. However, the distributed database system including the multi-database system has some problems. One of these problems is data migration between individual database systems in the multi-database system. Many reorganization techniques for distributed database systems are already proposed, but these techniques are not always adaptive to the data migration in the multi-database system. Incremental data migration is one of the solutions for this problem and it is easy to implement in the multi-database system. In this method, a large data migration is divided into small data migrations and other operations are inserted between these small data migrations. In this paper, the incremental data migration technique is evaluated in the multidatabase system based on MySQL with SPIDER storage engine and the improvement of the turn-around times of other operations is proved in this multi-database system.