
(1)
mysql> select * from t_worker;
+---------------+-----------+-------------+----------+----------+-----------+------------+
| department_id | worker_id | worker_date | wages | politics | name | borth_date |
+---------------+-----------+-------------+----------+----------+-----------+------------+
| 101 | 1001 | 2015-05-04 | 7500.00 | 群众 | 张春燕 | 1990-07-01 |
| 101 | 1002 | 2019-02-06 | 5200.00 | 团员 | 李名博 | 1997-02-08 |
| 102 | 1003 | 2008-01-04 | 10500.00 | 党员 | 王博涵 | 1983-06-08 |
| 102 | 1004 | 2016-10-10 | 5500.00 | 群众 | 赵小军 | 1994-09-05 |
| 102 | 1005 | 2014-04-01 | 8800.00 | 党员 | 钱有才 | 1992-12-30 |
| 103 | 1006 | 2019-05-05 | 5500.00 | 党员 | 孙菲菲 | 1996-09-02 |
+---------------+-----------+-------------+----------+----------+-----------+------------+
6 rows in set (0.00 sec)
(2)
mysql> select distinct department_id from t_worker;
+---------------+
| department_id |
+---------------+
| 101 |
| 102 |
| 103 |
+---------------+
3 rows in set (0.00 sec)
(3)
mysql> select count(*) as total_worker from t_worker;
+--------------+
| total_worker |
+--------------+
| 6 |
+--------------+
1 row in set (0.01 sec)
(4)
mysql> select max(wages) as max_wages, min(wages) as min_wages from t_worker;
+-----------+-----------+
| max_wages | min_wages |
+-----------+-----------+
| 10500.00 | 5200.00 |
+-----------+-----------+
1 row in set (0.00 sec)
(5)
mysql> select avg(wages) as avg_wages, sum(wages) as total_wages from t_worker;
+-------------+-------------+
| avg_wages | total_wages |
+-------------+-------------+
| 7166.666667 | 43000.00 |
+-------------+-------------+
1 row in set (0.00 sec)
(6)
mysql> create table work_date_table as select worker_id, name, worker_date from t_worker;
Query OK, 6 rows affected (0.03 sec)
Records: 6 Duplicates: 0 Warnings: 0
(7)
mysql> select timestampdiff(year, borth_date, curdate()) as age
-> from t_worker
-> where politics = '党员';
+------+
| age |
+------+
| 42 |
| 32 |
| 29 |
+------+
3 rows in set (0.00 sec)
(8)
mysql> select name from t_worker where wages between 4000 and 8000;
+-----------+
| name |
+-----------+
| 张春燕 |
| 李名博 |
| 赵小军 |
| 孙菲菲 |
+-----------+
4 rows in set (0.00 sec)
(9)
mysql> select name from t_worker where name like '孙%' or name like '李%';
+-----------+
| name |
+-----------+
| 李名博 |
| 孙菲菲 |
+-----------+
2 rows in set (0.00 sec)
(10)
mysql> select worker_id, name from t_worker
-> where department_id in (102, 103) and politics!= '党员';
+-----------+-----------+
| worker_id | name |
+-----------+-----------+
| 1004 | 赵小军 |
+-----------+-----------+
1 row in set (0.00 sec)
(11)
mysql> select * from t_worker order by borth_date;
+---------------+-----------+-------------+----------+----------+-----------+------------+
| department_id | worker_id | worker_date | wages | politics | name | borth_date |
+---------------+-----------+-------------+----------+----------+-----------+------------+
| 102 | 1003 | 2008-01-04 | 10500.00 | 党员 | 王博涵 | 1983-06-08 |
| 101 | 1001 | 2015-05-04 | 7500.00 | 群众 | 张春燕 | 1990-07-01 |
| 102 | 1005 | 2014-04-01 | 8800.00 | 党员 | 钱有才 | 1992-12-30 |
| 102 | 1004 | 2016-10-10 | 5500.00 | 群众 | 赵小军 | 1994-09-05 |
| 103 | 1006 | 2019-05-05 | 5500.00 | 党员 | 孙菲菲 | 1996-09-02 |
| 101 | 1002 | 2019-02-06 | 5200.00 | 团员 | 李名博 | 1997-02-08 |
+---------------+-----------+-------------+----------+----------+-----------+------------+
6 rows in set (0.00 sec)
(12)
mysql> select worker_id, name from t_worker order by wages desc limit 3;
+-----------+-----------+
| worker_id | name |
+-----------+-----------+
| 1003 | 王博涵 |
| 1005 | 钱有才 |
| 1001 | 张春燕 |
+-----------+-----------+
3 rows in set (0.00 sec)
(13)
mysql> select department_id, count(*) as party_member_count
-> from t_worker
-> where politics = '党员'
-> group by department_id;
+---------------+--------------------+
| department_id | party_member_count |
+---------------+--------------------+
| 102 | 2 |
| 103 | 1 |
+---------------+--------------------+
2 rows in set (0.00 sec)
(14)
mysql> select department_id, sum(wages) as total_department_wages, round(avg(wages), 2) as avg_department_wages
-> from t_worker
-> group by department_id;
+---------------+------------------------+----------------------+
| department_id | total_department_wages | avg_department_wages |
+---------------+------------------------+----------------------+
| 101 | 12700.00 | 6350 |
| 102 | 24800.00 | 8266.67 |
| 103 | 5500.00 | 5500 |
+---------------+------------------------+----------------------+
3 rows in set (0.00 sec)
(15)
mysql> select department_id, count(*) as total_count
-> from t_worker
-> group by department_id
-> having total_count >= 3;
+---------------+-------------+
| department_id | total_count |
+---------------+-------------+
| 102 | 3 |
+---------------+-------------+
1 row in set (0.00 sec)