数据库增删改查中的“查看”

📅 2026/7/20 17:24:01
数据库增删改查中的“查看”
要求1.建库建表1建库create database mydb8_worker;Query OK, 1 row affected (0.01 sec)mysql use mydb8_worker;Database changedmysql show databases;--------------------| Database |--------------------| information_schema || mydb1_test || mydb2_stuinfo || mydb3_employee || mydb4_product || mydb5_sales || mydb6_product || mydb7_openlab || mydb8_worker || mysql || performance_schema || sys || temp1 |--------------------13 rows in set (0.00 sec)2).建表mysql create table t_worker(department_id int(11) not null comment 部门号, worker_id int(11) primary key not null comment 职工号, worker_datedate 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, namevarchar(20) not null comment 姓名, borth_date date not null comment 出生日期);Query OK, 0 rows affected, 3 warnings (0.02 sec)2.插入数据mysql insert into t_worker values (101,1001,2015-5-4,7500.00,群众,张春燕,1990-7-1);Query OK, 1 row affected (0.00 sec)mysql insert into t_worker values (101,1002,2019-2-6,5200.00,团员,李名博,1997-2--8);Query OK, 1 row affected, 1 warning (0.00 sec)mysql insert into t_worker values (102,1003,2008-1-4,10500.00,党员,王博涵,1983-6-8);Query OK, 1 row affected (0.00 sec)mysql insert into t_worker values (102,1004,2016-10-10,5500.00,群众,赵小军,1994-9-5);Query OK, 1 row affected (0.00 sec)mysql insert into t_worker values (102,1005,2014-4-1,8800.00,党员,钱有财,1992-12-30);Query OK, 1 row affected (0.00 sec)mysql insert into t_worker values (103,1006,2019-5-5,5500.00,党员,孙菲菲,1996-9-2);Query OK, 1 row affected (0.01 sec)3.完成查询命令及截图1).显示所有职工的基本信息。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 | 钱有财 | 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).查询所有职工所属部门的部门号不显示重复的部门号。范樱select distinct department_id from t_worker;---------------| department_id |---------------| 101 || 102 || 103 |---------------3).求出所有职工的人数。范樱select count(worker_id) 职工人数 from t_worker;--------------| 职工人数 |--------------| 6 |--------------1 row in set (0.01 sec)4).列出最高工和最低工资。范樱select max(wages) 最高工资 , min(wages) 最低工资 from t_worker;----------------------------| 最高工资 | 最低工资 |----------------------------| 10500.00 | 5200.00 |----------------------------1 row in set (0.00 sec)5).列出职工的平均工资和总工资。范樱select avg(wages) 平均工资 , sum(wages) 总工资 from t_worker;-------------------------| 平均工资 | 总工资 |-------------------------| 7166.666667 | 43000.00 |-------------------------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。范樱create table t_workedate select worker_id,name,worker_date from t_worker;Query OK, 6 rows affected (0.03 sec)Records: 6 Duplicates: 0 Warnings: 0范樱select * from t_workedate;-----------------------------------| worker_id | name | worker_date |-----------------------------------| 1001 | 张春燕 | 2015-05-04 || 1002 | 李名博 | 2019-02-06 || 1003 | 王博涵 | 2008-01-04 || 1004 | 赵小军 | 2016-10-10 || 1005 | 钱有财 | 2014-04-01 || 1006 | 孙菲菲 | 2019-05-05 |-----------------------------------6 rows in set (0.00 sec)7).显示所有党员的年龄范樱select politics 政治面貌 , year(now())-year(borth_date) 年龄 from t_worker where----------------------| 政治面貌 | 年龄 |----------------------| 党员 | 43 || 党员 | 34 || 党员 | 30 |----------------------3 rows in set (0.00 sec)8).列出工资在4000一8000之间的所有职工姓名。范樱select name from t_worker where wages4000 and wages8000;-----------| name |-----------| 张春燕 || 李名博 || 赵小军 || 孙菲菲 |-----------4 rows in set (0.00 sec)9).列出所有孙姓和李姓的职工姓名。范樱select name from t_worker where name like 孙% or name like 李%;-----------| name |-----------| 李名博 || 孙菲菲 |-----------10).列出所有部门号为102和103且不是党员的职工号、姓名。范樱select worker_id,name from t_worker where (department_id102 or department_id103) a----------------------| worker_id | name |----------------------| 1004 | 赵小军 |----------------------1 row in set (0.00 sec)11).将职工表t_worker中的职工按出生的先后顺序排序。范樱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 | 钱有财 | 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).显示工资最高的前3名职工的职工号和姓名。范樱select worker_id,name from t_worker order by wages desc limit 3;----------------------| worker_id | name |----------------------| 1003 | 王博涵 || 1005 | 钱有财 || 1001 | 张春燕 |----------------------3 rows in set (0.00 sec)13).求出各部门党员的人数。范樱select department_id 部门编号 , count(worker_id) 人数 from t_worker where politics党员- group by department_id;----------------------| 部门编号 | 人数 |----------------------| 102 | 2 || 103 | 1 |----------------------2 rows in set (0.00 sec)14).统计各部门的工资和平均工资并保留2位小数范樱select department_id 部门编号 , sum(wages) 工资和值 , round(avg(wages)) 平均工资- from t_worker- group by 1;------------------------------------------| 部门编号 | 工资和值 | 平均工资 |------------------------------------------| 101 | 12700.00 | 6350 || 102 | 24800.00 | 8267 || 103 | 5500.00 | 5500 |------------------------------------------3 rows in set (0.00 sec)(15).列出总人数大于等于3的部门号和总人数。范樱select department_id 部门编号 , count(worker_id) 部门人数- from t_worker- group by 1 having count(worker_id)3;----------------------------| 部门编号 | 部门人数 |----------------------------| 102 | 3 |----------------------------1 row in set (0.00 sec)