MySQL account information is stored in the tables of the MySQL帐户信息存储在MySQL系统模式的表中。mysql system schema. This database and the access control system are discussed extensively in Chapter 5, MySQL Server Administration, which you should consult for additional details.该数据库和访问控制系统在第5章，“MySQL服务器管理”中进行了广泛的讨论，您应该参考该章了解更多详细信息。
Some MySQL releases introduce changes to the grant tables to add new privileges or features. 一些MySQL版本对grant表进行了更改，以添加新的特权或功能。To make sure that you can take advantage of any new capabilities, update your grant tables to the current structure whenever you upgrade MySQL. 为了确保可以利用任何新功能，请在升级MySQL时将grant表更新为当前结构。See Section 2.11, “Upgrading MySQL”.请参阅第2.11节，“升级MySQL”。
When the 启用read_only system variable is enabled, account-management statements require the CONNECTION_ADMIN privilege (or the deprecated SUPER privilege), in addition to any other required privileges. read_only系统变量时，帐户管理语句除了需要任何其他权限外，还需要CONNECTION_ADMIN权限（或不推荐的SUPER权限）。This is because they modify tables in the 这是因为它们修改mysql system schema.mysql系统架构中的表。
Account management statements are atomic and crash safe. 帐户管理对账单是原子的且安全崩溃。For more information, see Section 13.1.1, “Atomic Data Definition Statement Support”.有关更多信息，请参阅第13.1.1节，“原子数据定义语句支持”。