选出12个表中slary最大的人,把他们合成一个表的sql语句.
时间: 2024-03-01 22:53:18 浏览: 20
假设有12个表,分别为 `employee_1`、`employee_2`、...、`employee_12`,每个表都包含字段 `name` 和 `salary`,以下是选出12个表中salary最大的人并合成一个表的 SQL 语句:
```sql
SELECT name, MAX(salary) AS max_salary
FROM (
SELECT name, salary FROM employee_1
UNION ALL SELECT name, salary FROM employee_2
UNION ALL SELECT name, salary FROM employee_3
UNION ALL SELECT name, salary FROM employee_4
UNION ALL SELECT name, salary FROM employee_5
UNION ALL SELECT name, salary FROM employee_6
UNION ALL SELECT name, salary FROM employee_7
UNION ALL SELECT name, salary FROM employee_8
UNION ALL SELECT name, salary FROM employee_9
UNION ALL SELECT name, salary FROM employee_10
UNION ALL SELECT name, salary FROM employee_11
UNION ALL SELECT name, salary FROM employee_12
) subquery
GROUP BY name;
```
此 SQL 语句会从每个表中选出拥有最高工资的员工,并将他们的 `name` 和 `salary` 放入一个子表中。然后,使用 `GROUP BY` 子句对子表进行分组,以避免重复的 `name`。最后,使用 `MAX()` 聚合函数计算每个员工的最高工资。注意到在每个 `SELECT` 语句后面加上了 `UNION ALL`,以将所有选出来的数据合并到一个表中。
相关推荐
![](https://csdnimg.cn/download_wenku/file_type_ask_c1.png)
![zip](https://img-home.csdnimg.cn/images/20210720083736.png)
![zip](https://img-home.csdnimg.cn/images/20210720083736.png)
![docx](https://img-home.csdnimg.cn/images/20210720083331.png)
![zip](https://img-home.csdnimg.cn/images/20210720083736.png)
![zip](https://img-home.csdnimg.cn/images/20210720083736.png)
![zip](https://img-home.csdnimg.cn/images/20210720083736.png)
![zip](https://img-home.csdnimg.cn/images/20210720083736.png)