In order to progress team cooperative work, it is desirable that each member can not only refer to the shared resources, but also maintain his/her own private resources. In our previous paper, we proposed a database system in which users could maintain private data in their own private work spaces and use the shared data in a shared work space. In this paper, we propose a data management model where private and shared versions can be bound easily. Assume that, a user creates certain data and migrates a copy of the data to the shared work space. When the creator improves the data in the shared work space, he/she often refers the private versions left in the private work space. It is important to provide the whole history of versions.