【数据库SQL实战】查找当前薪水详情以及部门编号dept_no

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查找各个部门当前(to_date=’9999-01-01’)领导当前薪水详情以及其对应部门编号dept_no

CREATE TABLE

dept_manager

(

dept_no

char(4) NOT NULL,

emp_no

int(11) NOT NULL,

from_date

date NOT NULL,

to_date

date NOT NULL,

PRIMARY KEY (

emp_no

,

dept_no

));

CREATE TABLE

salaries

(

emp_no

int(11) NOT NULL,

salary

int(11) NOT NULL,

from_date

date NOT NULL,

to_date

date NOT NULL,

PRIMARY KEY (

emp_no

,

from_date

));

两种解法本质上都是连接两个表。

解法一：

select s.*,d.dept_no
from salaries s join dept_manager d
on s.emp_no=d.emp_no
where s.to_date = '9999-01-01' and d.to_date = '9999-01-01'

解法二:

SELECT s.*, d.dept_no
FROM salaries s ,  dept_manager d
WHERE s.to_date='9999-01-01'
AND d.to_date='9999-01-01'
AND s.emp_no = d.emp_no;