我从https://dev.mysql.com/doc/employee/en/
获得了员工示例数据库并导入我的mysql。
mysql> use employees;
Reading table information for completion of table and column names
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Database changed
mysql> show tables;
+----------------------+
| Tables_in_employees |
+----------------------+
| current_dept_emp |
| departments |
| dept_emp |
| dept_emp_latest_date |
| dept_manager |
| employees |
| salaries |
| test |
| titles |
+----------------------+
9 rows in set (0.00 sec)
mysql> describe employees;
+------------+---------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+------------+---------------+------+-----+---------+-------+
| emp_no | int(11) | NO | PRI | NULL | |
| birth_date | date | NO | | NULL | |
| first_name | varchar(14) | NO | | NULL | |
| last_name | varchar(16) | NO | | NULL | |
| gender | enum('M','F') | NO | | NULL | |
| hire_date | date | NO | | NULL | |
+------------+---------------+------+-----+---------+-------+
6 rows in set (0.00 sec)
mysql> describe departments;
+-----------+-------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+-----------+-------------+------+-----+---------+-------+
| dept_no | char(4) | NO | PRI | NULL | |
| dept_name | varchar(40) | NO | UNI | NULL | |
+-----------+-------------+------+-----+---------+-------+
2 rows in set (0.00 sec)
现在我想用这个数据库进行练习。
但是我无法找到该数据库的任何parctice主题。
例如给我一个问题包括一些条件然后让我写sql来解决这个问题。
像：
显示emp表中的员工详细信息。
SELECT * FROM EMP;
显示10号部门所有员工的员工姓名和工资。
SELECT ename, sal FROM EMP WHERE deptno=10;
显示为20号部门工作的所有员工的员工姓名，部门编号和工资，以及超过2500的工资。
SELECT ename, deptno, sal FROM emp WHERE deptno=20 AND sal>2500;
如果你知道请告诉我，谢谢！