a database management system has a plurality of database servers and data can be transferred between them by partitioning a data area into small areas and altering allocation of the small areas to the database servers . after altering the configuration , there occurs degradation in processing speed that accompanies re - creation of the index . if this problem is solved by using conventional techniques , noticeable degradation in processing speed will occur to a specific query at the time of a steady state operation . accordingly , an index created for each of the small areas and an index to all of the small areas are allocated to the database server and used in combination .