MySQL is commonly used commands for text subtotals, Commands, illustration, as reproduced or quoted, please put this article in connection prominently.
This article can be used as a common tool collection, as you praise a little help please support!
Since the SQL language belonging to class B, case-insensitive, for ease of reading, all SQL commands herein, all lowercase, do not spray.
Category commonly used commands:
Service level: Contains Start services, such as closed, popular to say that before entering MySQL, enter in a terminal, command and MySQL-related;
Database level: the establishment of a database that contains, or delete;
Data Sheet level: contains table creation, modification and other property, belonging to the pre-project design data tables related commands;
Level data: contains data add, delete, change, search, belongs to frequently used commands;
Description:
[Content parameter] - an optional parameter refers to
First, the service level commands (brief, does not involve the port, security, and other parameters)
1, start, stop, restart the MySQL service:
# win系统
>net start mysql # 启动
>net stop mysql # 停止
# ox系统，如果提示找不到命令，可直接进入安装目录的bin文件夹内运行命令
$ mysql.server start # 通过brew安装的MySQL 启动
$ mysql.server stop # 停止
$ mysql.server restart # 重启
# Linux系统，如果提示找不到命令，可直接进入安装目录的bin文件夹内运行命令
$ path_mysql/init.d/mysqld start # 启动 path_mysql是指安装路径
$ path_mysql/init.d/mysqld stop # 停止
$ path_mysql/init.d/mysqld restart # 重启
# 通过service 操作
$ service mysqld start # 启动
$ service mysqld stop # 停止
$ service mysqld restart # 重启
$ service mysql status # 查看服务状态
2, the first installation, start the configuration service, win system reference here
# ox系统
$ mysql_secure_installation
3, the first landing (newly installed, not configured)
# win系统
>mysql -hlocalhost -uroot
# ox系统
$mysql -uroot4, landing
mysql -u用户名 -p密码 # (密码)可省略，回车后再输入，如不省略，注意-p和密码间没有空格
例如：mysql -uroot -pmypasswd5, export / import database files (to be updated)
Second, the database level
1, the operation command
| command | Logogram | Specific meaning |
| ？ | ? | Displays help information |
| clear | c | Clear the current input statement |
| connect | r | Connecting to the server, and optional parameters for the host database |
| delimiter | d | Set the statement delimiter |
| ego | G | Send commands to the MySQL server, and displays the results |
| exit | q | Exit MySQL |
| go | g | Send commands to the MySQL server |
| help | h | Displays help information |
| notee | t | Do not write the output file |
| p | Print command | |
| prompt | R | MySQL prompt change |
| quit | q | Exit MySQL |
| rehash | # | Hash complete reconstruction |
| source | . | Execute a SQL script file to a file name as an argument |
| status | s | MySQL acquired from the server state information |
| tee | T | Set the output file, and the information is added to all given output file |
| use | in | With another database |
| charset | C | Switch to another character set |
| warning | W | After each statement displays a warning |
| nowarning | w | Do not display warnings after each statement |
2, commonly used commands
mysql>show databases; # 查看已有的数据库
mysql>create database 数据库名称 [dafault character set utf8]; # 创建[字符编码为utf8的]数据库
mysql>show create database 数据库名称; # 显示新创建的数据库信息
mysql>alter database 数据库名称 default character set gbk collate gbk_bin; #将数据库的编码格式设为 gbk 同时注意最后是设为gbk_bin，如果改为utf8，则最后是utf8_bin
mysql>drop database 数据库名称; # 删除数据库
mysql>use 数据库名称; # 切换至数据库 同 u [数据库名称] 注意：使用简写命令时最后不要加 ;mysql>select database(); # 显示当前所在的数据库
For example as follows:
mysql> create database test;
Query OK, 1 row affected (0.00 sec)
mysql> show create database test;
+----------+---------------------------------------------------------------+
| Database | Create Database |
+----------+---------------------------------------------------------------+
| test | CREATE DATABASE `test` /*!40100 DEFAULT CHARACTER SET utf8 */ |
+----------+---------------------------------------------------------------+
1 row in set (0.00 sec)
mysql> use test;
Database changed
mysql> select database();
+------------+
| database() |
+------------+
| test |
+------------+
1 row in set (0.00 sec)
mysql> drop database test;
Query OK, 0 rows affected (0.00 sec)
Third, the data table level
1, commonly used commands
mysql>show tables; # 显示当前数据库下所有数据表
mysql>create table 表名 (
字段名1 数据类型 [完整性约束条件]，
字段名2 数据类型 [完整性约束条件]，
字段名3 数据类型 [完整性约束条件]，
..........
)[engine=innodb]; # 创建数据表 [引擎类型,默认innodb]
mysql>show create table 表名； # 显示数据表的基本信息，含字段及其属性、引擎、字符集等
mysql>desc 表名; # 显示数据表信息，显示字段及其属性
mysql>alter table 原表名 rename to 新表名； # 修改数据表名
mysql>alter table 表名 change 原字段名 新字段名 新数据属性； # 修改表中字段
mysql>alter table 表名 modify 字段名 数据类型； # 修改表中字段属性
mysql>alter table 表名 add 新字段名 数据类型 [约束条件]； # 添加新字段
mysql>alter table 表名 drop 字段名； # 删除字段 （慎重！！！一般使用逻辑删除）
mysql>drop table 表名； # 删除数据表 （慎重！！！）
2, illustrated
mysql> show tables; # 显示所有数据表
+------------------+
| Tables_in_school |
+------------------+
| class |
| graduate |
| student |
| teacher |
+------------------+
4 rows in set (0.00 sec)
mysql> create table test( # 新建数据表，engine=innodb可省略
-> id int(100) unsigned not null primary key auto_increment,
-> age int(100)
-> )engine=innodb;
Query OK, 0 rows affected (0.03 sec)
mysql> show create table test; # 显示数据表详细信息
+-----------------+
| Table | Create Table |
+----------+
| test | CREATE TABLE `test` (
`id` int(100) unsigned NOT NULL AUTO_INCREMENT,
`age` int(100) DEFAULT NULL,
PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8 |
+--------------+
1 row in set (0.01 sec)
mysql> desc test; # 显示数据表字段信息
+-------+-------------------+------+-----+---------+----------------+
| Field | Type | Null | Key | Default | Extra |
+-------+-------------------+------+-----+---------+----------------+
| id | int(100) unsigned | NO | PRI | NULL | auto_increment |
| age | int(100) | YES | | NULL | |
+-------+-------------------+------+-----+---------+----------------+
2 rows in set (0.00 sec)
mysql> alter table test rename to test1; # 重命名数据表
Query OK, 0 rows affected (0.01 sec)
mysql> show tables;
+------------------+
| Tables_in_school |
+------------------+
| class |
| graduate |
| student |
| teacher |
| test1 |
+------------------+
5 rows in set (0.00 sec)
mysql> alter table test1 change age birthday date not null; # 修改数据表字段，含字段名和字段属性
Query OK, 0 rows affected (0.03 sec)
Records: 0 Duplicates: 0 Warnings: 0
mysql> desc test1;
+----------+-------------------+------+-----+---------+----------------+
| Field | Type | Null | Key | Default | Extra |
+----------+-------------------+------+-----+---------+----------------+
| id | int(100) unsigned | NO | PRI | NULL | auto_increment |
| birthday | date | NO | | NULL | |
+----------+-------------------+------+-----+---------+----------------+
2 rows in set (0.00 sec)
mysql> alter table test1 modify birthday datetime; # 修改字段属性
Query OK, 0 rows affected (0.03 sec)
Records: 0 Duplicates: 0 Warnings: 0
mysql> desc test1;
+----------+-------------------+------+-----+---------+----------------+
| Field | Type | Null | Key | Default | Extra |
+----------+-------------------+------+-----+---------+----------------+
| id | int(100) unsigned | NO | PRI | NULL | auto_increment |
| birthday | datetime | YES | | NULL | |
+----------+-------------------+------+-----+---------+----------------+
2 rows in set (0.00 sec)
mysql> alter table test1 drop birthday; # 删除字段
Query OK, 0 rows affected (0.02 sec)
Records: 0 Duplicates: 0 Warnings: 0
mysql> desc test1;
+-------+-------------------+------+-----+---------+----------------+
| Field | Type | Null | Key | Default | Extra |
+-------+-------------------+------+-----+---------+----------------+
| id | int(100) unsigned | NO | PRI | NULL | auto_increment |
+-------+-------------------+------+-----+---------+----------------+
1 row in set (0.00 sec)
mysql> drop table test1; # 删除数据表
Query OK, 0 rows affected (0.01 sec)
mysql> show tables;
+------------------+
| Tables_in_school |
+------------------+
| class |
| graduate |
| student |
| teacher |
+------------------+
4 rows in set (0.00 sec)
Fourth, the data level
1, commonly used commands
mysql>insert into 表名 [字段名1，字段名2，....] values
(值1，值2，.......),
(值1，值2，.......),
(值1，值2，.......)
........
; # 如使用字段，则添加的每条记录的值必须与字段一一对应；如不指定字段，则属于按位置添加数据，每条记录的值须同数据表中所有字段一一对应
mysql>update 表名 set
字段名1=值1,
字段名2=值2,
....
[where 条件]； # 更新/更改数据：[条件限制，如不加条件，则默认所有记录的该字段均修改]
mysql>alert table 表1名 add foreign key(字段1名) references 表2名(字段2名); # 为表1的字段1添加外键，连接表2的字段2，外键可选约束条件作为参数
mysql>alert table 表名 drop foreign key 字段名; # 删除外键
mysql>create [unique | fulltext | spatial] index 索引名 on 表名(字段名[asc | desc]); # 创建索引，索引会提高查找速度，但是会增加物理开销
mysql>drop index 索引名 on 表名; # 删除索引
mysql>delete from 表名 [where 条件]；# 删除表中数据[条件限制，如无条件，则清空数据表]
mysql>truncate table 表名; # 清空数据表
mysql>select 字段名1，字段名2，...... from 表名; # 查看表中数据，如查看所有数据使用 select * from 表名 ，这是数据查看的基本形式，后面的例子中会有拓展
2, illustrated
mysql> alter table student add foreign key(class) references class(cid); # 添加外键，如果表中有数据，则会添加失败
Query OK, 0 rows affected (0.03 sec)
Records: 0 Duplicates: 0 Warnings: 0
mysql> create index sid_index on student(sid); # 创建索引
Query OK, 0 rows affected (0.02 sec)
Records: 0 Duplicates: 0 Warnings: 0
mysql> show create table student;
+-----------------+
| Table | Create Table
+-----------------+
| student | CREATE TABLE `student` (
`sid` int(10) unsigned NOT NULL AUTO_INCREMENT,
`name` varchar(10) NOT NULL,
`gender` char(1) NOT NULL,
`age` int(3) unsigned NOT NULL,
`birthday` datetime NOT NULL,
`phone` varchar(11) DEFAULT NULL,
`class` int(10) unsigned NOT NULL,
`grade` int(10) unsigned NOT NULL,
PRIMARY KEY (`sid`),
KEY `sid_index` (`sid`), # 索引在这里
KEY `class` (`class`),
CONSTRAINT `student_ibfk_1` FOREIGN KEY (`class`) REFERENCES `class` (`cid`) # 这里显示外键的名称：student_ibfk_1，删除的时候要用这个字段
) ENGINE=InnoDB AUTO_INCREMENT=11 DEFAULT CHARSET=utf8 |
+-----------+
1 row in set (0.00 sec)
mysql> insert into class values # 添加数据，先添加class表数据，注意：如果存在外键，则外键所指向的数据表不能为空，否则无法添加数据
-> (1,'10级1班',1,45,'东教学楼1层'),
-> (2,'09级1班',2,48,'东教学楼2层'),
-> (3,'09级2班',2,50,'东教学楼2层'),
-> (4,'08级1班',3,51,'东教学楼3层'),
-> (5,'08级2班',4,49,'东教学楼3层');
Query OK, 5 rows affected (0.01 sec)
Records: 5 Duplicates: 0 Warnings: 0
mysql> insert into student values # 再添加student表数据
-> (1,'李杰','男',21,'1990-1-2',13012345678,1,1),
-> (2,'王倩','女',22,'1989-4-21',15212345678,1,1),
-> (3,'张大力','男',20,'1991-2-12',NULL,2,2),
-> (4,'王晓红','女',20,'1991-7-5',18900001111,2,2),
-> (5,'周大宝','男',21,'1990-12-23',NULL,3,2),
-> (6,'王志刚','男',22,'1989-10-10',NULL,3,2),
-> (7,'刘明','男',21,'1990-11-30',15912345678,4,3),
-> (8,'郭芙蓉','女',20,'1991-6-17',NULL,4,3),
-> (9,'李飞','男',23,'1988-12-3',13212345678,5,3),
-> (10,'苏洁','女',25,'1986-5-16',NULL,5,3);
Query OK, 10 rows affected (0.00 sec)
Records: 10 Duplicates: 0 Warnings: 0
mysql> select * from student; # 查询student 中所有数据
+-----+-----------+--------+-----+---------------------+-------------+-------+-------+
| sid | name | gender | age | birthday | phone | class | grade |
+-----+-----------+--------+-----+---------------------+-------------+-------+-------+
| 1 | 李杰 | 男 | 21 | 1990-01-02 00:00:00 | 13012345678 | 1 | 1 |
| 2 | 王倩 | 女 | 22 | 1989-04-21 00:00:00 | 15212345678 | 1 | 1 |
| 3 | 张大力 | 男 | 20 | 1991-02-12 00:00:00 | NULL | 2 | 2 |
| 4 | 王晓红 | 女 | 20 | 1991-07-05 00:00:00 | 18900001111 | 2 | 2 |
| 5 | 周大宝 | 男 | 21 | 1990-12-23 00:00:00 | NULL | 3 | 2 |
| 6 | 王志刚 | 男 | 22 | 1989-10-10 00:00:00 | NULL | 3 | 2 |
| 7 | 刘明 | 男 | 21 | 1990-11-30 00:00:00 | 15912345678 | 4 | 3 |
| 8 | 郭芙蓉 | 女 | 20 | 1991-06-17 00:00:00 | NULL | 4 | 3 |
| 9 | 李飞 | 男 | 23 | 1988-12-03 00:00:00 | 13212345678 | 5 | 3 |
| 10 | 苏洁 | 女 | 25 | 1986-05-16 00:00:00 | NULL | 5 | 3 |
+-----+-----------+--------+-----+---------------------+-------------+-------+-------+
10 rows in set (0.00 sec)
mysql> select sid,name,gender,age as '年龄' from student where class=3 and grade=2;
# 条件查询，查询class=3 & grade=2的学生sid、name、gender、age，并将age重命名
+-----+-----------+--------+--------+
| sid | name | gender | 年龄 |
+-----+-----------+--------+--------+
| 5 | 周大宝 | 男 | 21 |
| 6 | 王志刚 | 男 | 22 |
+-----+-----------+--------+--------+
2 rows in set (0.01 sec)
# 查询王倩同学的上课地点，显示姓名、性别及地点
mysql> select s.name,s.gender,c.location # 使用数据表简称获取响应的字段，如果该字段在所有使用的数据表中唯一，则可以不带表名，直接写字段
-> from student as s,class as c # 多表查询时，通常将每个表重命名为简称
-> where s.class=c.cid # 多表查询的连接依据
-> and s.name='王倩'; # 附加查询条件
+--------+--------+------------------+
| name | gender | location |
+--------+--------+------------------+
| 王倩 | 女 | 东教学楼1层 |
+--------+--------+------------------+
1 row in set (0.01 sec)
# 查看2年级的男女数量
mysql> select gender,count(*) from student where grade=2 group by gender; # 使用group by实现分组 count()是聚合函数
+--------+----------+
| gender | count(*) |
+--------+----------+
| 女 | 1 |
| 男 | 3 |
+--------+----------+
2 rows in set (0.01 sec)
mysql> select gender,count(*) from student where grade=2 group by gender having gender='男';
# group by 后面可以加条件语句having，having可以使用聚合函数，而where是不可以的
+--------+----------+
| gender | count(*) |
+--------+----------+
| 男 | 3 |
+--------+----------+
1 row in set (0.01 sec)
# 查询人数大于2的年级中，显示年级、人数、各年级的学生平均年龄、男生数量,并安装平均年龄倒序显示
mysql> select grade,count(*),avg(age),count(gender='男')
-> from student
-> group by grade
-> having count(*)>2 and count(gender='男')
-> order by avg(age) desc;
+-------+----------+----------+---------------------+
| grade | count(*) | avg(age) | count(gender='男') |
+-------+----------+----------+---------------------+
| 3 | 4 | 22.2500 | 4 |
| 2 | 4 | 20.7500 | 4 |
+-------+----------+----------+---------------------+
2 rows in set (0.00 sec)
A common query structure:
查询语句 执行顺序
select [distinct] * | 字段1，字段2，..| 聚合函数 ⑤
from 表1 as a,表2 as b ..... ①
join on a.id=b.id ....... ②
where 字段|isfull [= > < is not in like between and or ] 值 (子查询)..... ③
group by 字段 ④
having 条件 [聚合函数] ⑥
order by 字段 | [聚合函数] [asc | desc] ⑦
limit [offset] 数量; ⑧