数据库状态：
读写
ALTER DATABASE [DB] SET READ_WRITE WITH ROLLBACK IMMEDIATE
只读
ALTER DATABASE [DB] SET READ_ONLY WITH ROLLBACK IMMEDIATE
http://msdn.microsoft.com/zh-cn/library/bb522682.aspx
拒绝数据库权限
DENY DELETE TO [DB]
授予数据库权限
REVOKE UPDATE TO [CRM]
http://msdn.microsoft.com/zh-cn/library/ms187728(v=sql.105).aspx