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# ALL

Joe 想从员工表

```mysql
create table employee(
    id int primary key auto_increment,
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    dept_id int,
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    name varchar(256),
    post varchar(16)
)
```

中找出所有其所在部门没有助理(post 为 `assistant`)的员工信息。由于 Joe 没有其它表的查询权限,他只能查询员工表,这个查询应该是:

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## 答案

```mysql
select id, name, dept 
from employee as o
where 'assistant' != all(select post from employee as i where o.dept = i.dept); 
```

## 选项

### A

```mysql
select id, name, dept 
from employee as o
where 'assistant' = all(select post from employee as i where o.dept = i.dept); 
```

### B

```mysql
select id, name, dept 
from employee as o
where 'assistant' != all(select post from employee as i where o.dept = i.dept); 
```

### C
```mysql
select id, name, dept 
from employee as o
where 'assistant' != all(select post from employee as i); 
```

### D

```mysql
select id, name, dept 
from employee as o
where 'assistant' != ANY(select post from employee as i where o.dept = i.dept); 
```