创建用户zs,密码123456, 创建角色R1,并分配权限如下:student表的select、insert;sc表的delete、update(grade) 给用户zs分配角色R1 验证zs权限 回收zs在sc表的update(grade)权限 验证zs权限
时间: 2024-02-18 09:05:04 浏览: 149
好的,您的问题是如何在数据库中创建用户、角色、分配权限、验证权限和回收权限。以下是基于Oracle数据库的解答:
1. 创建用户zs,密码123456:
```sql
CREATE USER zs IDENTIFIED BY 123456;
```
2. 创建角色R1:
```sql
CREATE ROLE R1;
```
3. 分配权限:
```sql
GRANT SELECT, INSERT ON student TO R1;
GRANT DELETE, UPDATE(grade) ON sc TO R1;
```
4. 给用户zs分配角色R1:
```sql
GRANT R1 TO zs;
```
5. 验证zs权限:
```sql
-- 验证student表的select权限
SELECT * FROM student;
-- 验证student表的insert权限
INSERT INTO student VALUES (1, 'John', 'Doe');
-- 验证sc表的delete权限
DELETE FROM sc WHERE student_id = 1 AND course_id = 1;
-- 验证sc表的update(grade)权限
UPDATE sc SET grade = 80 WHERE student_id = 1 AND course_id = 1;
```
6. 回收zs在sc表的update(grade)权限:
```sql
REVOKE UPDATE(grade) ON sc FROM zs;
```
7. 验证zs权限:
```sql
-- 验证student表的select权限
SELECT * FROM student;
-- 验证student表的insert权限
INSERT INTO student VALUES (1, 'John', 'Doe');
-- 验证sc表的delete权限
DELETE FROM sc WHERE student_id = 1 AND course_id = 1;
-- 验证sc表的update(grade)权限
UPDATE sc SET grade = 80 WHERE student_id = 1 AND course_id = 1; -- 这条语句会报错,因为权限已经被回收了。
```
希望这样的解答能够帮到您。
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