Sử dụng cơ sở dữ liệu cố định vai trò tài khoản cơ sở dữ liệu Tạo và quyền phân công rõ ràng là rất nhiều công việc. Khi bạn xem xét rằng SQL Server cài đặt dịch vụ nhất hàng chục đến hàng trăm người sử dụng | Use Fixed Database Roles Creating database accounts and assigning permissions is obviously a lot of work. When you consider that most SQL Server installations service dozens to hundreds of users it s easy to see that a considerable amount of time and effort goes into administering database security. All in all creating and managing a database security scheme is one of the most time- and effort-intensive tasks of any database administrator. Fortunately SQL Server provides a tool to considerably lighten this administrative load. As you ll see in this section SQL Server makes it easy to assign predefined permissions to groups of users rather than individually handling each user. Setting up database object permissions for individual users is a hassle. Every time a user account is added to SQL Server the permissions on database objects must be set for the user. I d like to be able to minimize the amount of time spent designing individual object permissions for my users. Technique SQL Server defines many built-in fixed database roles that grant or deny permissions on database objects. Each fixed database role adds or subtracts permissions on all the tables stored procedures or other database objects within the database. A user who is added to a fixed database role inherits all the permissions specified by the role. A person can belong to multiple roles if necessary. Steps A fixed database role is similar in some ways to the fixed server roles discussed earlier in this chapter. The difference is that fixed database roles determine permissions to perform operations on objects within a single database whereas fixed server roles specify the administrative operations that are permitted on all SQL Server databases. SQL Server defines 10 different fixed database roles db_owner. As owners of the database members of this role can perform any task that is granted to the other fixed database roles. The db_owner role includes all administrative design and data access .
