MySQL（五）单表查询

一、插入

　　select * from mysql.user;     # 会显示的乱，由于一行内容（字段记录）太多屏幕显示不开

　　select * from mysql.userG     #把一条记录按行显示

　　把原来一张表里面的几个记录或（一张表里有多条记录但是有用的仅仅有几条）迁移到一张新的表里，那么就可以这样：

　　需要host字段与user字段：

　　　　create table user(host char(60),user char(16)) select host,user from mysql.use

　　注意：如果在新建的表里字段和原表的字段不一样就会出现以下情况会把IP与port当成全新的字段而且是空记录

mysql>  create table user1(ip char(60),port char(16)) select host,user from mysql.user;
Query OK, 4 rows affected (0.27 sec)
Records: 4  Duplicates: 0  Warnings: 0

mysql> select * from user1;
+------+------+-----------+---------------+
| ip   | port | host      | user          |
+------+------+-----------+---------------+
| NULL | NULL | %         | wang          |
| NULL | NULL | localhost | mysql.session |
| NULL | NULL | localhost | mysql.sys     |
| NULL | NULL | localhost | root          |
+------+------+-----------+---------------+
4 rows in set (0.00 sec)

mysql> desc user1;
+-------+----------+------+-----+---------+-------+
| Field | Type     | Null | Key | Default | Extra |
+-------+----------+------+-----+---------+-------+
| ip    | char(60) | YES  |     | NULL    |       |
| port  | char(16) | YES  |     | NULL    |       |
| host  | char(60) | NO   |     |         |       |
| user  | char(32) | NO   |     |         |       |
+-------+----------+------+-----+---------+-------+
4 rows in set (0.00 sec)

 别名：as关键字,不加也行

　　这样也是可以的：

　　create table user2(ip char(60),username char(16)) select host as ip,user as username from mysql.user;   

　　查询时也可以取个别名：

mysql> select host 主机名,user 用户名 from mysql.user;
+-----------+---------------+
| 主机名    | 用户名        |
+-----------+---------------+
| %         | wang          |
| localhost | mysql.session |
| localhost | mysql.sys     |
| localhost | root          |
+-----------+---------------+
4 rows in set (0.00 sec)

二、更新与删除

　　更新：update db1.t1 set 字段=值 where id>10 or id < 30;　

　　　　update mysql.user set password=password('123')
    　　　　where host='localhost' and user='root';
　删除表中的某一个字段：
　　　　delete from 表名 where 字段名 条件 字段内容；

　　清空表：
　　　　truncate 表名；
三、单表查询语法与简单查询：
单表查询语法：

select distinct 字段1，字段2，字段3。。。。 from 表名
    where 约束条件
    group by 分组的字段
    having 过滤条件
    order by 排序字段
    limit 限制条件;
顺序是：
（1）先找到这张表from，
（2）看看有么有约束条件，拿着where指定的约束条件，去文件/表中取出一条条记录，
（3）将取出的一条条记录进行group by分组，如果没有group by，则整体作为一组，
（4）将分组的结果进行having过滤，
（5）执行select，
（6）distinct去重，
（7）将结果按条件排序：order by，
（8）限制结果的显示条数）。

company.employee
    员工id      id                  int             
    姓名        emp_name            varchar
    性别        sex                 enum
    年龄        age                 int
    入职日期     hire_date           date
    岗位        post                varchar
    职位描述     post_comment        varchar
    薪水        salary              double
    办公室       office              int
    部门编号     depart_id           int



#创建表
create table employee(
id int not null unique auto_increment,
name varchar(20) not null,
sex enum('male','female') not null default 'male', #大部分是男的
age int(3) unsigned not null default 28,
hire_date date not null,
post varchar(50),
post_comment varchar(100),
salary double(15,2),
office int, #一个部门一个屋子
depart_id int
);


#查看表结构
mysql> desc employee;
+--------------+-----------------------+------+-----+---------+----------------+
| Field        | Type                  | Null | Key | Default | Extra          |
+--------------+-----------------------+------+-----+---------+----------------+
| id           | int(11)               | NO   | PRI | NULL    | auto_increment |
| name         | varchar(20)           | NO   |     | NULL    |                |
| sex          | enum('male','female') | NO   |     | male    |                |
| age          | int(3) unsigned       | NO   |     | 28      |                |
| hire_date    | date                  | NO   |     | NULL    |                |
| post         | varchar(50)           | YES  |     | NULL    |                |
| post_comment | varchar(100)          | YES  |     | NULL    |                |
| salary       | double(15,2)          | YES  |     | NULL    |                |
| office       | int(11)               | YES  |     | NULL    |                |
| depart_id    | int(11)               | YES  |     | NULL    |                |
+--------------+-----------------------+------+-----+---------+----------------+

#插入记录
#三个部门：教学，销售，运营
insert into employee(name,sex,age,hire_date,post,salary,office,depart_id) values
('egon','male',18,'20170301','老男孩驻沙河办事处外交大使',7300.33,401,1), #以下是教学部
('alex','male',78,'20150302','teacher',1000000.31,401,1),
('wupeiqi','male',81,'20130305','teacher',8300,401,1),
('yuanhao','male',73,'20140701','teacher',3500,401,1),
('liwenzhou','male',28,'20121101','teacher',2100,401,1),
('jingliyang','female',18,'20110211','teacher',9000,401,1),
('jinxin','male',18,'19000301','teacher',30000,401,1),
('成龙','male',48,'20101111','teacher',10000,401,1),

('歪歪','female',48,'20150311','sale',3000.13,402,2),#以下是销售部门
('丫丫','female',38,'20101101','sale',2000.35,402,2),
('丁丁','female',18,'20110312','sale',1000.37,402,2),
('星星','female',18,'20160513','sale',3000.29,402,2),
('格格','female',28,'20170127','sale',4000.33,402,2),

('张野','male',28,'20160311','operation',10000.13,403,3), #以下是运营部门
('程咬金','male',18,'19970312','operation',20000,403,3),
('程咬银','female',18,'20130311','operation',19000,403,3),
('程咬铜','male',18,'20150411','operation',18000,403,3),
('程咬铁','female',18,'20140512','operation',17000,403,3)
;

#简单查询
    select * from employee;

    select name,salary from employee;

#避免重复distinct
    select distinct post from employee;    

 
 

通过四则运算查询
    selct name, salary*12 FROM employee;
    select name, salary*12 as 年薪 from employee;
    select name 名字, salary*12 年薪 from employee;
    select  name, salary+1000 as 月薪 from employee;

mysql>     select name, salary*12 as 年薪 from employee;
+------------+-------------+
| name       | 年薪        |
+------------+-------------+
| egon       |    87603.96 |
| alex       | 12000003.72 |
| wupeiqi    |    99600.00 |
| yuanhao    |    42000.00 |
| liwenzhou  |    25200.00 |
| jingliyang |   108000.00 |
| jinxin     |   360000.00 |
| 成龙       |   120000.00 |
| 歪歪       |    36001.56 |
| 丫丫       |    24004.20 |
| 丁丁       |    12004.44 |
| 星星       |    36003.48 |
| 格格       |    48003.96 |
| 张野       |   120001.56 |
| 程咬金     |   240000.00 |
| 程咬银     |   228000.00 |
| 程咬铜     |   216000.00 |
| 程咬铁     |   204000.00 |
+------------+-------------+
18 rows in set (0.00 sec)

mysql>     select name 名字, salary*12 年薪 from employee;
+------------+-------------+
| 名字       | 年薪        |
+------------+-------------+
| egon       |    87603.96 |
| alex       | 12000003.72 |
| wupeiqi    |    99600.00 |
| yuanhao    |    42000.00 |
| liwenzhou  |    25200.00 |
| jingliyang |   108000.00 |
| jinxin     |   360000.00 |
| 成龙       |   120000.00 |
| 歪歪       |    36001.56 |
| 丫丫       |    24004.20 |
| 丁丁       |    12004.44 |
| 星星       |    36003.48 |
| 格格       |    48003.96 |
| 张野       |   120001.56 |
| 程咬金     |   240000.00 |
| 程咬银     |   228000.00 |
| 程咬铜     |   216000.00 |
| 程咬铁     |   204000.00 |
+------------+-------------+
18 rows in set (0.01 sec)

mysql>     select  name, salary+1000 as 月薪 from employee;
+------------+------------+
| name       | 月薪       |
+------------+------------+
| egon       |    8300.33 |
| alex       | 1001000.31 |
| wupeiqi    |    9300.00 |
| yuanhao    |    4500.00 |
| liwenzhou  |    3100.00 |
| jingliyang |   10000.00 |
| jinxin     |   31000.00 |
| 成龙       |   11000.00 |
| 歪歪       |    4000.13 |
| 丫丫       |    3000.35 |
| 丁丁       |    2000.37 |
| 星星       |    4000.29 |
| 格格       |    5000.33 |
| 张野       |   11000.13 |
| 程咬金     |   21000.00 |
| 程咬银     |   20000.00 |
| 程咬铜     |   19000.00 |
| 程咬铁     |   18000.00 |
+------------+------------+
18 rows in set (0.00 sec)

定义显示格式
   concat() 函数用于连接字符串
   select concat('姓名: ',name,'  年薪: ', salary*12)  from employee;

mysql> select concat('姓名: ',name,'  年薪: ', salary*12)  from employee;
+---------------------------------------------+
| concat('姓名: ',name,'  年薪: ', salary*12) |
+---------------------------------------------+
| 姓名: egon  年薪: 87603.96                  |
| 姓名: alex  年薪: 12000003.72               |
| 姓名: wupeiqi  年薪: 99600.00               |
| 姓名: yuanhao  年薪: 42000.00               |
| 姓名: liwenzhou  年薪: 25200.00             |
| 姓名: jingliyang  年薪: 108000.00           |
| 姓名: jinxin  年薪: 360000.00               |
| 姓名: 成龙  年薪: 120000.00                 |
| 姓名: 歪歪  年薪: 36001.56                  |
| 姓名: 丫丫  年薪: 24004.20                  |
| 姓名: 丁丁  年薪: 12004.44                  |
| 姓名: 星星  年薪: 36003.48                  |
| 姓名: 格格  年薪: 48003.96                  |
| 姓名: 张野  年薪: 120001.56                 |
| 姓名: 程咬金  年薪: 240000.00               |
| 姓名: 程咬银  年薪: 228000.00               |
| 姓名: 程咬铜  年薪: 216000.00               |
| 姓名: 程咬铁  年薪: 204000.00               |
+---------------------------------------------+

   concat_ws() 第一个参数为分隔符
   select concat_ws(':',name,salary*12) from employee;  
　　

mysql> select concat_ws(':',name,salary*12) from employee;
+-------------------------------+
| concat_ws(':',name,salary*12) |
+-------------------------------+
| egon:87603.96                 |
| alex:12000003.72              |
| wupeiqi:99600.00              |
| yuanhao:42000.00              |
| liwenzhou:25200.00            |
| jingliyang:108000.00          |
| jinxin:360000.00              |
| 成龙:120000.00                |
| 歪歪:36001.56                 |
| 丫丫:24004.20                 |
| 丁丁:12004.44                 |
| 星星:36003.48                 |
| 格格:48003.96                 |
| 张野:120001.56                |
| 程咬金:240000.00              |
| 程咬银:228000.00              |
| 程咬铜:216000.00              |
| 程咬铁:204000.00              |
+-------------------------------+
18 rows in set (0.00 sec)

四、where约束条件

1. 比较运算符：> < >= <= <> !=
2. between 80 and 100 值在80到100之间
3. in(80,90,100) 值是80或90或100
4. like 'egon%'
    pattern可以是%或_，
    %表示任意多字符
    _表示任意一个字符
5. 逻辑运算符：在多个条件直接可以使用逻辑运算符 and or not

select id,name from employee where post='teacher';
select id,name from employee where id >=3 and id < 5;
select id,name from employee where id <=3 or id >= 5;

select id,name from employee where id between 3 and 5;
select id,name from employee where id >=3 and id <= 5;

select id,name,age from employee
    where age = 38 or age = 28 or age = 48 or age = 18;

select id,name,age from employee
    where age not in (60,70,80,18,'aaa');

select id,name,age from employee
    where name like 'e%';  # 名字以e开头的

select id,name,age from employee
    where name not like '___';  #名字有3个字符的

# null并不是空字符串

　　mysql> select * from employee where not post_comment is null;
　　Empty set (0.02 sec)

　　mysql> select * from employee where not post_comment is ' ';
　　ERROR 1064 (42000): You have an error in your SQL syntax; check the manual that corresponds to your MySQL 　　server version for the right syntax to use near '' '' at line 1

1. 查看岗位是teacher的员工姓名、年龄
2. 查看岗位是teacher且年龄大于30岁的员工姓名、年龄
3. 查看岗位是teacher且薪资在9000-10000范围内的员工姓名、年龄、薪资
4. 查看岗位描述不为NULL的员工信息
5. 查看岗位是teacher且薪资是10000或9000或30000的员工姓名、年龄、薪资
6. 查看岗位是teacher且薪资不是10000或9000或30000的员工姓名、年龄、薪资
7. 查看岗位是teacher且名字是jin开头的员工姓名、年薪

1、select name,age from employee where post='teacher';

2、select name,age from employee where post='teacher' and age > 30;

3、select name,age,salary from employee where post='teacher' and salary between 9000 and 10000;

4、select * from employee where not post_comment is null;

5、select name,age,salary from employee where post='teacher' and salary in (10000,9000,30000);

6、select name,age,salary from employee where post='teacher' and salary not in (10000,9000,30000);

7、select name,salary*12 from employee where post='teacher' and name like 'jin%';
    

五、分组：group by

1、首先明确一点：分组发生在where之后，即分组是基于where之后得到的记录而进行的
2、分组指的是：将所有记录按照某个相同的字段进行归类，比如针对员工信息表的职位分组，或者按照性别分组等
3、查询条件里有‘每’这个字，就是我们分组的依据
4、可以按照任意字段分组，但是分组后只能查看分组的字段，如果想查看组内信息需要借助于聚合函数

#强调：
1、分组之后，select只能查看到分组的字段，要想查组内内容
不能直接查看，需要借助于聚合函数max，min，avg，sum，count
2、分组的目的是为类以组为单位来处理记录，而不是处理单独的记录
3、如果我们用unique的字段作为分组的依据，则每一条记录自成一组，这种分组没有意义
多条记录之间的某个字段值相同，该字段通常用来作为分组的依据

ONLY_FULL_GROUP_BY
在5.6中貌似ONLY_FULL_GROUP_BY是没设置的，那么问题来了：

如果统计每个部门的员工姓名，写成这样就会变成如下图所示，但实际不是这样的
　

所以，为了不让这种情况出现，我们可以修改下配置文件　　

　　set global sql_mode = 'only_full_group_by'; 设置，设置完后退出重新登录

　　select @@global.sql_mode;    查看

设置完后就会报错

#查看MySQL 5.7默认的sql_mode如下：
mysql> select @@global.sql_mode;
ONLY_FULL_GROUP_BY,STRICT_TRANS_TABLES,NO_ZERO_IN_DATE,NO_ZERO_DATE,ERROR_FOR_DIVISION_BY_ZERO,NO_AUTO_CREATE_USER,NO_ENGINE_SUBSTITUTION

#！！！注意
ONLY_FULL_GROUP_BY的语义就是确定select target list中的所有列的值都是明确语义，简单的说来，在ONLY_FULL_GROUP_BY模式下，target list中的值要么是来自于聚集函数的结果，要么是来自于group by list中的表达式的值。


#设置sql_mole如下操作(我们可以去掉ONLY_FULL_GROUP_BY模式)：
mysql> set global sql_mode='STRICT_TRANS_TABLES,NO_ZERO_IN_DATE,NO_ZERO_DATE,ERROR_FOR_DIVISION_BY_ZERO,NO_AUTO_CREATE_USER,NO_ENGINE_SUBSTITUTION';

六、聚合函数
常用于GROUP BY从句的SELECT查询中

AVG(col)返回指定列的平均值
COUNT(col)返回指定列中非NULL值的个数
MIN(col)返回指定列的最小值
MAX(col)返回指定列的最大值
SUM(col)返回指定列的所有值之和
GROUP_CONCAT(col) 返回由属于一组的列值连接组合而成的结果

1. 查询总员工数:没有分组，默认整体一组
2. 查看每个部门的员工数
3. 查看teacher部门的员工数
4. 查询岗位名以及岗位包含的所有员工名字
5. 查询岗位名以及各岗位内包含的员工个数
6. 查询公司内男员工和女员工的个数
7. 查询岗位名以及各岗位的平均薪资
8. 查询岗位名以及各岗位的最高薪资
9. 查询岗位名以及各岗位的最低薪资
10. 查询男员工与男员工的平均薪资，女员工与女员工的平均薪资

1、select count(id) from employee;

2、select post,count(id) from employee group by post;

3、select count(id) from employee where post='teacher';

4、select post,group_concat(name) from employee group by post;

5、select post,count(id) from employee group by post;

6、select sex,count(id) from employee group by sex;

7、select post,avg(salary) from employee group by post;

8、select post,max(salary) from employee group by post;

9、select post,min(salary) from employee group by post;

10、select sex,avg(salary) from employee group by sex;

七、having过滤条件

　　having与where不一样的地方在于！！！　

　　！！！执行优先级从高到低：where > group by > having 
　　1. Where 发生在分组group by之前，因而Where中可以有任意字段，但是绝对不能使用聚合函数。
　　2. Having发生在分组group by之后，因而Having中可以使用分组的字段，无法直接取到其他字段,可以使用聚合函数

　　 where可以：select * from employee where salary > 10000;
　　hanving不可以：

mysql> select post from employee group by post;
ERROR 1046 (3D000): No database selected
mysql> select * from employee having salary > 10000;
ERROR 1046 (3D000): No database selected

1、取出员工数大于3的部门
2、取出id是大于10的,员工数大于3的部门
3、查询各岗位内包含的员工个数小于2的岗位名、岗位内包含员工名字、个数
4、查询各岗位平均薪资大于10000的岗位名、平均工资
5、查询各岗位平均薪资大于10000且小于20000的岗位名、平均工资

1、select post from employee group by post having count(id) > 3;

2、select post from employee where id > 10 group by post having count(id) > 3;

3、select post,group_concat(name),count(id) from employee group by post having count(id) < 2;

4、select post,avg(salary) from employee group by post having avg(salary) > 10000;

5、select post,avg(salary) from employee group by post having avg(salary) > 10000 and avg(salary) < 20000;

八、distinct ：去重

查出公司都有哪些办公室，部门编号和岗位。

mysql> select distinct office,depart_id,post  from employee;
+--------+-----------+----------------------------+
| office | depart_id | post                       |
+--------+-----------+----------------------------+
|    401 |         1 | 老男孩驻沙河办事处外交大使 |
|    401 |         1 | teacher                    |
|    402 |         2 | sale                       |
|    403 |         3 | operation                  |
+--------+-----------+----------------------------+
4 rows in set (0.00 sec)

九、查询排序：order by

默认是asc排序（升序），desc排序（降序）

按单列排序
    SELECT * FROM employee ORDER BY salary;
    SELECT * FROM employee ORDER BY salary ASC;
    SELECT * FROM employee ORDER BY salary DESC;

按多列排序:先按照age排序，如果年纪相同，则按照薪资排序

　　SELECT * from employee ORDER BY age,salary DESC;

1. 查询所有员工信息，先按照age升序排序，如果age相同则按照hire_date降序排序
2. 查询各岗位平均薪资大于10000的岗位名、平均工资,结果按平均薪资升序排列
3. 查询各岗位平均薪资大于10000的岗位名、平均工资,结果按平均薪资降序排列

1、select * from employee ORDER BY age asc,hire_date desc;
2、select post,avg(salary) from employee group by post having avg(salary) > 10000 order by avg(salary) asc;
3、select post,avg(salary) from employee group by post having avg(salary) > 10000 order by avg(salary) desc;

十、limit限制条数

查出公司的前三个员工的信息
mysql> select * from employee limit 3; #默认从头开始
+----+---------+------+-----+------------+----------------------------+--------------+------------+--------+-----------+
| id | name    | sex  | age | hire_date  | post                       | post_comment | salary     | office | depart_id |
+----+---------+------+-----+------------+----------------------------+--------------+------------+--------+-----------+
|  1 | egon    | male |  18 | 2017-03-01 | 老男孩驻沙河办事处外交大使 | NULL         |    7300.33 |    401 |         1 |
|  2 | alex    | male |  78 | 2015-03-02 | teacher                    | NULL         | 1000000.31 |    401 |         1 |
|  3 | wupeiqi | male |  81 | 2013-03-05 | teacher                    | NULL         |    8300.00 |    401 |         1 |
+----+---------+------+-----+------------+----------------------------+--------------+------------+--------+-----------+
3 rows in set (0.00 sec)

查出公司工资最高的3个人信息
mysql> select * from employee order by salary desc limit 3;
+----+--------+------+-----+------------+-----------+--------------+------------+--------+-----------+
| id | name   | sex  | age | hire_date  | post      | post_comment | salary     | office | depart_id |
+----+--------+------+-----+------------+-----------+--------------+------------+--------+-----------+
|  2 | alex   | male |  78 | 2015-03-02 | teacher   | NULL         | 1000000.31 |    401 |         1 |
|  7 | jinxin | male |  18 | 1900-03-01 | teacher   | NULL         |   30000.00 |    401 |         1 |
| 15 | 程咬金 | male |  18 | 1997-03-12 | operation | NULL         |   20000.00 |    403 |         3 |
+----+--------+------+-----+------------+-----------+--------------+------------+--------+-----------+
3 rows in set (0.00 sec)

分页显示，一页显示三个
mysql> select * from employee limit 0,3;  #3,3  #6,3
+----+---------+------+-----+------------+----------------------------+--------------+------------+--------+-----------+
| id | name    | sex  | age | hire_date  | post                       | post_comment | salary     | office | depart_id |
+----+---------+------+-----+------------+----------------------------+--------------+------------+--------+-----------+
|  1 | egon    | male |  18 | 2017-03-01 | 老男孩驻沙河办事处外交大使 | NULL         |    7300.33 |    401 |         1 |
|  2 | alex    | male |  78 | 2015-03-02 | teacher                    | NULL         | 1000000.31 |    401 |         1 |
|  3 | wupeiqi | male |  81 | 2013-03-05 | teacher                    | NULL         |    8300.00 |    401 |         1 |
+----+---------+------+-----+------------+----------------------------+--------------+------------+--------+-----------+
3 rows in set (0.00 sec)

查出公司从第七个员工开始的后三个员工信息
mysql> select * from employee limit 6,3;
+----+--------+--------+-----+------------+---------+--------------+----------+--------+-----------+
| id | name   | sex    | age | hire_date  | post    | post_comment | salary   | office | depart_id |
+----+--------+--------+-----+------------+---------+--------------+----------+--------+-----------+
|  7 | jinxin | male   |  18 | 1900-03-01 | teacher | NULL         | 30000.00 |    401 |         1 |
|  8 | 成龙   | male   |  48 | 2010-11-11 | teacher | NULL         | 10000.00 |    401 |         1 |
|  9 | 歪歪   | female |  48 | 2015-03-11 | sale    | NULL         |  3000.13 |    402 |         2 |
+----+--------+--------+-----+------------+---------+--------------+----------+--------+-----------+

十一、使用正则表达式查询

^ 行首，开头
$ 行尾，结尾
. 除了换行符以外的任意单个字符
* 前导字符的零个或多个
.* 所有字符
[] 字符组内的任一字符
[^] 对字符组内的每个字符取反(不匹配字符组内的每个字符)
^[^] 非字符组内的字符开头的行
[a-z] 小写字母
[A-Z] 大写字母
[a-Z] 小写和大写字母
[0-9] 数字
<</font> 单词头 单词一般以空格或特殊字符做分隔,连续的字符串被当做单词
> 单词尾
x+:左边的那一个字符有1个到无穷个
x?:左边的那一个字符有0个到1个
x{n}:左边的那一个字符有n个
x{n,m}:左边的那一个字符有n个到m个
x{n,}:左边的那x一个字符有n个到无穷个
|   或

查出公司以a开头的员工信息

mysql> select * from employee where name regexp '^a';
+----+------+------+-----+------------+---------+--------------+------------+--------+-----------+
| id | name | sex  | age | hire_date  | post    | post_comment | salary     | office | depart_id |
+----+------+------+-----+------------+---------+--------------+------------+--------+-----------+
|  2 | alex | male |  78 | 2015-03-02 | teacher | NULL         | 1000000.31 |    401 |         1 |
+----+------+------+-----+------------+---------+--------------+------------+--------+-----------+
1 row in set (0.00 sec)

查出公司以n结尾的员工姓名

mysql> select name from employee where name regexp 'n$';
+--------+
| name   |
+--------+
| egon   |
| jinxin |
+--------+
2 rows in set (0.00 sec)

查看所有员工中名字是jin开头，n或者g结果的员工信息

mysql> select * from employee where name regexp 'n$';
+----+--------+------+-----+------------+----------------------------+--------------+----------+--------+-----------+
| id | name   | sex  | age | hire_date  | post                       | post_comment | salary   | office | depart_id |
+----+--------+------+-----+------------+----------------------------+--------------+----------+--------+-----------+
|  1 | egon   | male |  18 | 2017-03-01 | 老男孩驻沙河办事处外交大使 | NULL         |  7300.33 |    401 |         1 |
|  7 | jinxin | male |  18 | 1900-03-01 | teacher                    | NULL         | 30000.00 |    401 |         1 |
+----+--------+------+-----+------------+----------------------------+--------------+----------+--------+-----------+
2 rows in set (0.00 sec)