PURPOSE: To transfer units of data between transaction systems at a high speed in environment of DBMS sharing disks.

CONSTITUTION: An owner-side system which updates pages generates an update number for a page to be stored together with a lock processed by the owner-side system. When a requester-side system requests a record of the page, a requester- side request inhibits a display showing that a version newer than the page is needed for a local memory. An element of the buffer manager of the DBMS transfers pages between memories from the owner-side DBMS using an overhead communication protocol of low order to the requester-side DBMS with the assistance of a lock manager. The transfer of the pages requires neither the I/O processing of disks nor the I/O processing of a log for the update of the pages.