Fine-grained access control for database management systems

A practical approach for developing fine-grained access control (FGAC) for database management systems is reported in this paper. We extend SQL language to support security policies. The concept of the policy type for databases is proposed. We implement the policy reuse through the use of policy types and policy instances to alleviate the administration workload of maintaining security policies. The policies for rows and columns can be expressed with policy types. Moreover, complicated database integrity constraints can also be expressed by policy types, and no further purpose-built programs are needed to create specific security control policies. We implement the fine-grained access control in a relational database management system DM5 [4]. The performance test results based on TPC-W are also presented.