Since databases are the primary repositories of information for today‎'‎s organizations and governments‎,‎ database security has become critically important‎.‎ Introducing the concept of multilevel security in relational databases‎,‎ this book provides a comparative study of the various models that support multilevel security policies in the relational database‎-illustrating the strengths and weaknesses of each model‎.‎ Multilevel Security for Relational Databases covers multilevel database security concepts along with many other multilevel database security models and techniques‎.‎ It presents a prototype that readers can implement as a tool for conducting performance evaluations to compare multilevel secure database models‎.‎ The book supplies a complete view of an encryption‎-based multilevel security database model that integrates multilevel security for the relational database with a system that encrypts each record with an encryption key according to its security class level‎.‎ This model will help you utilize an encryption system as a second security layer over the multilevel security layer for the database‎,‎ reduce the multilevel database size‎,‎ and improve the response time of data retrieval from the multilevel database‎.‎ Considering instance‎-based multilevel database security‎,‎ the book covers relational database access controls and examines concurrency control in multilevel database security systems‎.‎ It includes database encryption algorithms‎,‎ simulation programs‎,‎ and Visual studio and Microsoft SQL Server code‎.‎