用户访问数据库被拒绝

Question

我有一个具有以下权限的用户'adminuser'：

mysql> show grants for 'adminuser'@'localhost';
+----------------------------------------------------------+
| Grants for adminuser@localhost                         |
+----------------------------------------------------------+
| GRANT ALL PRIVILEGES ON *.* TO 'adminuser'@'localhost' |
+----------------------------------------------------------+
1 row in set (0.00 sec)

现在我正在尝试向刚刚创建的其他用户授予权限

mysql> grant delete, insert, update, select, create, index on simpledb.* to 'jobuser'@'localhost';

但是我收到了错误：

ERROR 1044 (42000): Access denied for user 'adminuser'@'localhost' to database 'simpledb'

为什么？