With the popularity and development of distributed systems, the problem of integration of multiple access control mechanisms of database systems emerged inevitably. Theories on graph and state machine are used to research the mapping from local access control mechanism to the global access control mechanism. An integration model: Authorization Propagation Tree (APT) model which support DAC, MAC and RBAC is proposed to solve it in the paper. The paper also gives the formal definition and security proving of the security model for the relation Database integrated access control model (DBIAC) based on APT.