Linux系统安装mysql数据库

前言

第一次安装linux系统的mysql数据库，经过各种error，终于安装完成，记录下来以备查看。

安装流程

下载安装软件

官网下载mysql-5.7.25-linux-glibc2.12-x86_64.tar.gz
https://cdn.mysql.com//Downloads/MySQL-5.7/mysql-5.7.25-linux-glibc2.12-x86_64.tar.gz

解压文件，将解压的文件拷贝到/usr/local/mysql

tar -zxvf mysql-5.7.25-linux-glibc2.12-x86_64.tar.gz

创建配置文件my.cnf

vi /etc/my.cnf

粘帖以下内容：

[mysql]
#设置mysql客户端默认字符集
default-character-set=utf8 
[mysqld]
skip-name-resolve
#设置3306端口
port = 3306 
# 设置mysql的安装目录
basedir=/usr/local/mysql/
# 设置mysql数据库的数据的存放目录
datadir=/usr/local/mysql/data
# 允许最大连接数
max_connections=200
# 服务端使用的字符集默认为8比特编码的latin1字符集
character-set-server=utf8
# 创建新表时将使用的默认存储引擎
default-storage-engine=INNODB 
lower_case_table_names=1
max_allowed_packet=16M
log-error = /usr/local/mysql/log/error.log
pid-file = /usr/local/mysql/pid/mysql.pid
user = root
tmpdir = /tmp
socket = /tmp/mysql.sock
explicit_defaults_for_timestamp=true

为mysql目录授权

groupadd mysql
useradd -r -g mysql mysql
cd /usr/local/mysql
chown -R mysql:mysql ./

安装和初始化

初始化mysql数据库（initialize常见异常解决见下方）
命令目录/usr/local/mysql

bin/mysqld --initialize
cp ./support-files/mysql.server /etc/init.d/mysqld
chown 777 /etc/my.cnf
chmod +x /etc/init.d/mysqld

启动mysql

/etc/init.d/mysqld start

结果如下

Starting MySQL... SUCCESS! 

查看数据库状态

netstat -lntp 

结果如下

Active Internet connections (only servers)
Proto Recv-Q Send-Q Local Address               Foreign Address             State       PID/Program name   
tcp        0      0 :::3306                     :::*                        LISTEN      17965/mysqld        

登录mysql

mysql -u root -p

忘记root密码详见常见异常中修改root密码

常见异常

bin/mysqld --initialize问题总汇

问题
bin/mysqld: error while loading shared libraries: libaio.so.1: cannot open shared object file: No such file or directory
解决
yum install -y libaio

问题
bin/mysqld: error while loading shared libraries: libnuma.so.1: cannot open shared object file: No such file or directory
解决
yum -y install numactl.x86_64

--initialize specified but the data directory has files in it. Aborting
没有找到data路径，从/etc/my.cnf配置文件中找到data文件路径
datadir=/usr/local/mysql/data
根据配置信息建好文件路径
## 如何创建一个注脚

Could not open file '/usr/local/mysql/log/error.log' for error logging: No such file or directory
没有找到log路径，从/etc/my.cnf配置文件中找到log文件路径
log-error = /usr/local/mysql/log/error.log
根据配置信息建好文件路径

mysql命令不可用

-bash: mysql: command not found
打开编辑系统环境变量文件 /etc/profile
把 MySQL 的 bin 路径加入到环境变量中：
export PATH=$PATH://usr/local/mysql/bin
执行profile
. /etc/profile

新装数据库修改root密码

修改root密码
停掉mysqld服务

[[email protected] mysql]# service mysqld stop
Shutting down MySQL.. SUCCESS! 

修改my.cnf配置文件

[[email protected] mysql]# vi /etc/my.cnf

在[mysqld]的段中加上一句：skip-grant-tables 保存并且退出vi。

启动mysqld服务

[[email protected] mysql]# service mysqld start
Starting MySQL. SUCCESS! 
[[email protected] mysql]# mysql
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 2
Server version: 5.7.22 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.
 
mysql> 

登录并修改MySQL的root密码

mysql> USE mysql ; 
mysql> update user set password=password("*******") where user="*******";  #修改密码报错
ERROR 1054 (42S22): Unknown column 'password' in 'field list'
mysql> update mysql.user set authentication_string=password('*******') where user='*******';  #修改密码成功
Query OK, 1 row affected, 1 warning (0.00 sec)
Rows matched: 1  Changed: 1  Warnings: 1 
mysql> flush privileges ; 
mysql> exit

将my.cnf配置改回来

vi /etc/my.cnf

将刚才在[mysqld]的段中加上的skip-grant-tables删除
保存并且退出vi。
重新启动mysqld

service mysqld restart