Relational algebra and SQL operations are the foundation for data manipulation and retrieval in relational database management systems (RDBMS). Understanding these operations provides insight into how ...
Abstract: Recently, the ability of the computer i s not only used in calculation, but also the ability to store and provide information that eventually formed a system called database. Database as ...
Abstract: We develop formal authorization allocation algorithms for role-based access control (RBAC). The formal approaches are based on relational structure, and relational algebra and operations.