題目描述
獲取所有部門當前manager的當前薪水情況,給出dept_no, emp_no以及salary,當前表示to_date='9999-01-01'
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`));
輸出描述
dept_no | emp_no | salary |
---|---|---|
d001 | 10002 | 72527 |
d004 | 10004 | 74057 |
d003 | 10005 | 94692 |
d002 | 10006 | 43311 |
d006 | 10010 | 94409 |
試題詳解
使用INNER JOIN內連接dept_manager表和salaries表並限制連接條件爲emp_no和to_date字段。代碼如下:
SELECT d.dept_no,d.emp_no,s.salary
FROM dept_manager AS d INNER JOIN salaries AS s
ON d.emp_no = s.emp_no
AND d.to_date = '9999-01-01'
AND s.to_date = '9999-01-01';