MySQL的安装与配置及登陆与退出
1、安装与配置MySQL：
/usr/bin：客户端程序和脚本
/usr/sbin：mysql 服务器
/var/lib/mysql：日志文件、数据库文件
/usr/share/mysql：错误消息和字符集文件
/etc/my.cnf：配置文件
2、修改数据库的密码：
登陆数据库：
[[email protected]_0_13_centos ~]# mysql -uroot -p
Enter password:
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 2
Server version: 5.7.23 MySQL Community Server (GPL)
Copyright (c) 2000, 2018, Oracle and/or its affiliates. All rights reserved.
Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.
Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.
选择mysql数据库：
mysql> use mysql;
Reading table information for completion of table and column names
You can turn off this feature to get a quicker startup with -A
Database changed修改root密码为123456：
3、启动、终止mysql：
终止mysql之后，就不能登陆mysql了：
[[email protected]_0_13_centos ~]# service mysqld stop
Redirecting to /bin/systemctl stop mysqld.service
[[email protected]_0_13_centos ~]# mysql -uroot -p
Enter password:
ERROR 2002 (HY000): Can't connect to local MySQL server through socket '/var/lib/mysql/mysql.sock' (2)重启mysql，然后就可以登陆mysql了：
[[email protected]_0_13_centos ~]# service mysqld restart
Redirecting to /bin/systemctl restart mysqld.service
[[email protected]_0_13_centos ~]# mysql -uroot -p
Enter password:
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 2
Server version: 5.7.23 MySQL Community Server (GPL)
Copyright (c) 2000, 2018, Oracle and/or its affiliates. All rights reserved.
Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.
Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.
4、使用\s查看数据库的状态，字符集编码方式不是utf8会出现乱码。
mysql> \s;
--------------
mysql Ver 14.14 Distrib 5.7.23, for Linux (x86_64) using EditLine wrapper
Connection id: 2
Current database:
Current user: [email protected]
SSL: Not in use
Current pager: stdout
Using outfile: ''
Using delimiter: ;
Server version: 5.7.23 MySQL Community Server (GPL)
Protocol version: 10
Connection: Localhost via UNIX socket
Server characterset: latin1
Db characterset: latin1
Client characterset: utf8
Conn. characterset: utf8
UNIX socket: /var/lib/mysql/mysql.sock
Uptime: 2 min 32 sec
Threads: 1 Questions: 5 Slow queries: 0 Opens: 105 Flush tables: 1 Open tables: 98 Queries per second avg: 0.032
--------------
ERROR:
No query specified
5、将编码方式改成utf8，否则会出现乱码现象：
找到my.cnf配置文件：/etc
vim打开配置文件，设置字符集：
客户端字符集[mysql]：default-character-set=utf8；
服务器端字符集[mysqld]：character-set-server=utf8；
然后终止和重启mysql，再来看一下状态，可以使用\s或者status：
mysql> status
--------------
mysql Ver 14.14 Distrib 5.7.23, for Linux (x86_64) using EditLine wrapper
Connection id: 2
Current database:
Current user: [email protected]
SSL: Not in use
Current pager: stdout
Using outfile: ''
Using delimiter: ;
Server version: 5.7.23 MySQL Community Server (GPL)
Protocol version: 10
Connection: Localhost via UNIX socket
Server characterset: utf8
Db characterset: utf8
Client characterset: utf8
Conn. characterset: utf8
UNIX socket: /var/lib/mysql/mysql.sock
Uptime: 38 sec
Threads: 1 Questions: 5 Slow queries: 0 Opens: 105 Flush tables: 1 Open tables: 98 Queries per second avg: 0.131
--------------
现在编码方式都变成utf8了，就不会出现乱码现象了。
6、登陆/退出MySQL：
登陆方式：
A、使用用户名和密码：
[[email protected]_0_13_centos ~]# mysql -uroot -pB、使用IP地址登陆：
#mysql -hIP地址 -uroot -p；
C、使用IP地址和端口号：
#mysql -hIP地址 -P端口号 -uroot -p
退出的三种方式：
exit；quit；\q
7、输出mysql版本信息并且退出：
[[email protected]_0_13_centos ~]# mysql -V
mysql Ver 14.14 Distrib 5.7.23, for Linux (x86_64) using EditLine wrapper