1.建表
mysql> create table worker(
department_id int(11) not null comment '部门号',
worker_id int(11) primary key not null comment '职工号',
worker_date date not null comment '工作时间',
wages float(8,2) not null comment '工资',
politics varchar(10) not null default '群众' comment '政治面貌',
name varchar(20) not null comment '姓名',
borth_date date not null comment '出生日期' );
2.插入数据
mysql> insert into worker values (101,1001,'2015-5-4',3500.00,'群众','张三','1990-7-1');
mysql> insert into worker values (101,1002,'2017-2-6',3200.00,'团员','李四','1997-2--8');
mysql> insert into worker values (102,1003,'2011-1-4',8500.00,'党员','王亮','1983-6-8');
mysql> insert into worker values (102,1004,'2016-10-10',5500.00,'群众','赵六','1994-9-5');
mysql> insert into worker values (102,1005,'2014-4-1',4800.00,'党员','钱七','1992-12-30');
mysql> insert into worker values (102,1006,'2017-5-5',4500.00,'党员','孙八','1996-92-2');
3.完成查询
(1)、显示所有职工的基本信息。
mysql> select * from worker;
+---------------+-----------+-------------+---------+----------+--------+------------+
| department_id | worker_id | worker_date | wages | politics | name | borth_date |
+---------------+-----------+-------------+---------+----------+--------+------------+
| 101 | 1001 | 2015-05-04 | 3500.00 | 群众 | 张三 | 1990-07-01 |
| 101 | 1002 | 2017-02-06 | 3200.00 | 团员 | 李四 | 1997-02-08 |
| 102 | 1003 | 2011-01-04 | 8500.00 | 党员 | 王亮 | 1983-06-08 |
| 102 | 1004 | 2016-10-10 | 5500.00 | 群众 | 赵六 | 1994-09-05 |
| 102 | 1005 | 2014-04-01 | 4800.00 | 党员 | 钱七 | 1992-12-30 |
| 102 | 1006 | 2017-05-05 | 4500.00 | 党员 | 孙八 | 1996-09-02 |
+---------------+-----------+-------------+---------+----------+--------+------------+
6 rows in set (0.00 sec)
(2)、查询所有职工所属部门的部门号，不显示重复的部门号。
mysql> select distinct department_id from worker;
+---------------+
| department_id |
+---------------+
| 101 |
| 102 |
+---------------+
2 rows in set (0.00 sec)
(3)、求出所有职工的人数。
mysql> select count(*) as 职工人数 from worker;
+--------------+
| 职工人数 |
+--------------+
| 6 |
+--------------+
1 row in set (0.00 sec)
(4)、列出最高工和最低工资。
mysql> select max(wages) as '最高工资',min(wages) as '最低工资' from worker;
+--------------+--------------+
| 最高工资 | 最低工资 |
+--------------+--------------+
| 8500.00 | 3200.00 |
+--------------+--------------+
1 row in set (0.00 sec)
(5)、列出职工的平均工资和总工资。
mysql> select sum(wages) as `总工资`, avg(wages) as `平均工资` from worker;
+-----------+--------------+
| 总工资 | 平均工资 |
+-----------+--------------+
| 30000.00 | 5000.000000 |
+-----------+--------------+
1 row in set (0.00 sec)
(6)、创建一个只有职工号、姓名和参加工作的新表，名为工作日期表workdate（数据来源于worker表）
# 提示：用复制表的语法
mysql> create table workdate
-> select worker_id, name, worker_date from worker;
Query OK, 6 rows affected (0.00 sec)
Records: 6 Duplicates: 0 Warnings: 0
(7)、显示所有党员的年龄。
mysql> select name, timestampdiff(year,birth_date,curdate()) as `年龄`
-> from worker
-> where politics='党员';
+--------+--------+
| name | 年龄 |
+--------+--------+
| 王亮 | 43 |
| 钱七 | 33 |
| 孙八 | 30 |
+--------+--------+
3 rows in set (0.00 sec)
(8)、列出工资在2000－5000之间的所有职工姓名。
mysql> select name from worker where wages between 2000 and 5000;
+--------+
| name |
+--------+
| 张三 |
| 李四 |
| 钱七 |
| 孙八 |
+--------+
4 rows in set (0.00 sec)
(9)、列出所有孙姓和李姓的职工姓名。
mysql> select name from worker where name like '孙%' or name like '李%';
+--------+
| name |
+--------+
| 李四 |
| 孙八 |
+--------+
2 rows in set (0.00 sec)
(10)、列出所有部门号为2和3且不是党员的职工号、姓名。
mysql> select worker_id, name from worker where department_id in(102,103) and politics<>'党员';
+-----------+--------+
| worker_id | name |
+-----------+--------+
| 1004 | 赵六 |
+-----------+--------+
1 row in set (0.00 sec)
(11)、将职工表worker中的职工按出生的先后顺序排序。
mysql> select * from worker order by birth_date asc;
+---------------+-----------+-------------+---------+----------+--------+------- -----+
| department_id | worker_id | worker_date | wages | politics | name | birth_ date |
+---------------+-----------+-------------+---------+----------+--------+------- -----+
| 102 | 1003 | 2011-01-04 | 8500.00 | 党员 | 王亮 | 1983-0 6-08 |
| 101 | 1001 | 2015-05-04 | 3500.00 | 群众 | 张三 | 1990-0 7-01 |
| 102 | 1005 | 2014-04-01 | 4800.00 | 党员 | 钱七 | 1992-1 2-30 |
| 102 | 1004 | 2016-10-10 | 5500.00 | 群众 | 赵六 | 1994-0 9-05 |
| 102 | 1006 | 2017-05-05 | 4500.00 | 党员 | 孙八 | 1996-0 9-02 |
| 101 | 1002 | 2017-02-06 | 3200.00 | 团员 | 李四 | 1997-0 2-08 |
+---------------+-----------+-------------+---------+----------+--------+------- -----+
6 rows in set (0.00 sec)
(12)、显示工资最高的前3名职工的职工号和姓名。
mysql> select worker_id,name from worker order by wages desc limit 3;
+-----------+--------+
| worker_id | name |
+-----------+--------+
| 1003 | 王亮 |
| 1004 | 赵六 |
| 1005 | 钱七 |
+-----------+--------+
3 rows in set (0.00 sec)
(13)、求出各部门党员的人数。
mysql> select department_id, count(*) as `党员人数`
-> from worker
-> where politics='党员'
-> group by department_id;
+---------------+--------------+
| department_id | 党员人数 |
+---------------+--------------+
| 102 | 3 |
+---------------+--------------+
1 row in set (0.00 sec)
(14)、统计各部门的工资和平均工资
mysql> select department_id, sum(wages) as `部门总工资`, avg(wages) as `部门平均工资`
from worker group by department_id;
+---------------+-----------------+--------------------+
| department_id | 部门总工资 | 部门平均工资 |
+---------------+-----------------+--------------------+
| 101 | 6700.00 | 3350.000000 |
| 102 | 23300.00 | 5825.000000 |
+---------------+-----------------+--------------------+
2 rows in set (0.00 sec)
(15)、列出总人数大于等于4的部门号和总人数。
mysql> select department_id, count(*) as '总人数' from worker group by department_id having count(*)>=4;
+---------------+-----------+
| department_id | 总人数 |
+---------------+-----------+
| 102 | 4 |
+---------------+-----------+
1 row in set (0.00 sec)
