In today's world, data is generated at a very rapid speed and final destination of such data is database. Data is stored in database for easy and efficient way to manage these data. All the operations of data manipulation and maintenance are done using Database Management System. Considering the importance of data in organization, it is absolutely essential to secure the data present in the database. A secure database is the one which is reciprocated from different possible database attacks. Security models are required to develop for databases. These models are different in many aspects as they are dealing with different issues of the database security. They may different also because of they are taking different assumptions about what con...