Abstract: Database technology is one of the most widely applied computer technologies, its security is becoming more and more important. This paper starts from the definition of database security, discusses the problems of user authorization, access control, security management and database encryption. The main present domestic applications that improve the security of database through the method of revisions of database are discussed in detail. At last, the existing problems of database security are proposed and the future research directions are also indicated

Key words: Database security; Revisions of database; Authentication

摘要： 数据库技术是应用最广泛的一门计算机技术，它的安全越来越重要。该文从数据库安全的定义入手，对用户认证、存取控制、安全管理和数据库加密等数据库安全技术的几个方面进行了讨论。并对国内目前采用改造数据库的方式来提高数据库安全的几个主要应用，进行了详尽的阐述，最后指出了数据库安全现存的问题和将来研究的方向。

关键词: 数据库安全；数据库改造；认证