RedHat7上安装MySQL5.7.16

1、查看系统中是否已将安装MySQL，如果安装了，需要卸载。

[root@chenguo etc]# rpm -qa|grep -i mysql

2、创建用户和组

[root@chenguo ~]# groupadd mysql
[root@chenguo ~]# useradd -r -g mysql -p root mysql

3、通过SSH将mysql安装包放到/usr/local目录下面，并进行解压操作。

[chenguo@chenguo ~]$ cd /usr/local/
[chenguo@chenguo local]$ tar -xvf mysql-5.7.-.el7.x86_64.rpm-bundle.tar 

解压之后出现如下：

mysql-community-libs-compat-5.7.-.el7.x86_64.rpm
mysql-community-devel-5.7.-.el7.x86_64.rpm
mysql-community-minimal-debuginfo-5.7.-.el7.x86_64.rpm
mysql-community-libs-5.7.-.el7.x86_64.rpm
mysql-community-common-5.7.-.el7.x86_64.rpm
mysql-community-embedded-compat-5.7.-.el7.x86_64.rpm
mysql-community-test-5.7.-.el7.x86_64.rpm
mysql-community-embedded-devel-5.7.-.el7.x86_64.rpm
mysql-community-server-minimal-5.7.-.el7.x86_64.rpm
mysql-community-server-5.7.-.el7.x86_64.rpm
mysql-community-client-5.7.-.el7.x86_64.rpm
mysql-community-embedded-5.7.-.el7.x86_64.rpm

4、安装时候会提示与已经安装的RPM包有冲突，所以我们先卸载一些RPM包，要卸载哪些呢？我们要卸载的是包含有mariadb关键字的RPM包，执行命令：

[chenguo@chenguo local]$ rpm -qa|grep mariadb
mariadb-libs-5.5.-.el7_0.x86_64

使用命令卸载：

[chenguo@chenguo local]$ su -
[root@chenguo ~]# rpm -e mariadb-libs-5.5.-.el7_0.x86_64 --nodeps

或者使用：

[root@chenguo ~]# rpm -e --nodeps mariadb-libs-5.5.-.el7_0.x86_64 

5、进行MySQL包安装

[root@chenguo lib]# su -chenguo
[chenguo@chenguo lib]$ cd /usr/local/
[chenguo@chenguo local]$ rpm -ivh mysql-community-common-5.7.-.el7.x86_64.rpm
warning: mysql-community-common-5.7.-.el7.x86_64.rpm: Header V3 DSA/SHA1 Signature, key ID 5072e1f5: NOKEY
error: can't create transaction lock on /var/lib/rpm/.rpm.lock (Permission denied)

出现错误，改用root用户进行安装：

[chenguo@chenguo local]$ su -
[root@chenguo local]# rpm -ivh mysql-community-common-5.7.16-1.el7.x86_64.rpm
warning: mysql-community-common-5.7.16-1.el7.x86_64.rpm: Header V3 DSA/SHA1 Signature, key ID 5072e1f5: NOKEY
Preparing...                          ################################# [100%]
Updating / installing...
   1:mysql-community-common-5.7.16-1.e################################# [100%]
[root@chenguo local]# rpm -ivh mysql-community-libs-5.7.16-1.el7.x86_64.rpm
warning: mysql-community-libs-5.7.16-1.el7.x86_64.rpm: Header V3 DSA/SHA1 Signature, key ID 5072e1f5: NOKEY
Preparing...                          ################################# [100%]
Updating / installing...
   1:mysql-community-libs-5.7.16-1.el7################################# [100%]
[root@chenguo local]# rpm -ivh mysql-community-client-5.7.16-1.el7.x86_64.rpm
warning: mysql-community-client-5.7.16-1.el7.x86_64.rpm: Header V3 DSA/SHA1 Signature, key ID 5072e1f5: NOKEY
Preparing...                          ################################# [100%]
Updating / installing...
   1:mysql-community-client-5.7.16-1.er################################# [100%])
[root@chenguo local]# rpm -ivh mysql-community-server-5.7.16-1.el7.x86_64.rpm
warning: mysql-community-server-5.7.16-1.el7.x86_64.rpm: Header V3 DSA/SHA1 Signature, key ID 5072e1f5: NOKEY
Preparing...                          ################################# [100%]
Updating / installing...
   1:mysql-community-server-5.7.16-1.e################################# [100%]

6、命令执行完毕后，mysql就安装完成，下面需要做的就是对mysql 进行初始化

[root@chenguo bin]# cd /usr/local/bin
[root@chenguo bin]# mysqld --initialize --user=mysql
[root@chenguo bin]# mysqld --initialize-insecure --user=mysql
--18T08::.910921Z  [Warning] TIMESTAMP with implicit DEFAULT value is deprecated. Please use --explicit_defaults_for_timestamp server option (see documentation for more details).
--18T08::.912342Z  [ERROR] --initialize specified but the data directory has files in it. Aborting.
--18T08::.912368Z  [ERROR] Aborting

解决办法：

进入/var/lib/目录中查看是否有mysql目录，有的话进行删除：

[root@chenguo bin]# cd /var/lib
[root@chenguo lib]#  rm -rf mysql
[root@chenguo local]# cd /usr/local/bin/
[root@chenguo bin]# mysqld --initialize-insecure --user=mysql

7、启动mysql服务

[root@chenguo lib]# systemctl start mysqld
Job for mysqld.service failed. See 'systemctl status mysqld.service' and 'journalctl -xn' for details.

启动失败解决办法：

首先，查看/var/lib/mysql-files目录是否存在：

[root@chenguo lib]# ls -ld /var/lib/mysql-files

如果不显示任何信息就表示不存在，执行命令：

[root@chenguo lib]# mkdir /var/lib/mysql-files

这时，我们试着执行命令：

[root@chenguo lib]# systemctl start mysqld

如果还出现和下图一样的提示，我们执行另一条命令：

[root@chenguo lib]# chown -R mysql:mysql /var/lib/mysql

依然出错。

查看日志信息：

[root@chenguo ~]# journalctl |grep mysql

启动失败也有可能是SElinux导致，关闭SElinux功能：

vim /etc/selinux/config 修改文件永久关闭

# This file controls the state of SELinux on the system.
# SELINUX= can take one of these three values:
# enforcing - SELinux security policy is enforced.
# permissive - SELinux prints warnings instead of enforcing.
# disabled - No SELinux policy is loaded.
SELINUX=enforcing
# SELINUXTYPE= can take one of three two values:
# targeted - Targeted processes are protected,
# minimum - Modification of targeted policy. Only selected processes are protected.
# mls - Multi Level Security protection.
SELINUXTYPE=targeted

SELINUX=permissive #修改此参数为permissive

查看系统日志：

[root@chenguo ~]# cd /var/log
[root@chenguo log]# cat mysqld.log 

--22T02::.860176Z  [ERROR] InnoDB: Operating system error number  in a file operation.
--22T02::.860231Z  [ERROR] InnoDB: The error means mysqld does not have the access rights to the directory.
--22T02::.860238Z  [ERROR] InnoDB: os_file_get_status() failed on './ibdata1'. Can't determine file permissions
--22T02::.860246Z  [ERROR] InnoDB: Plugin initialization aborted with error Generic error
--22T02::.471773Z  [ERROR] Plugin 'InnoDB' init function returned error.
--22T02::.471974Z  [ERROR] Plugin 'InnoDB' registration as a STORAGE ENGINE failed.
--22T02::.472096Z  [ERROR] Failed to initialize plugins.
--22T02::.472245Z  [ERROR] Aborting

[root@chenguo bin]# ls -ld /usr/sbin/mysqld
-rwxr-xr-x.  root root  Sep  : /usr/sbin/mysqld
[root@chenguo bin]# chown -R mysql:mysql /usr/sbin/mysqld

启动之后依然报错

还原权限：

[root@chenguo bin]# chown -R root:root /usr/sbin/mysqld

在重启了系统之后，使用：

[root@chenguo lib]# systemctl start mysqld

居然神奇的成功了，搞不懂。应该是最后的vim /etc/selinux/config 修改文件永久关闭，这个操作实现的

8、允许mysql远程访问

[root@chenguo ~]# mysql
mysql> use mysql;
mysql> select host, user from user;
mysql> update user set host = '%' where user = 'root';
mysql> select host, user from user;

9、退出mysql

mysql> exit

10、查看和修改数据库编码

[root@chenguo ~]# mysql
mysql> use mysql;
mysql> select Host,user from user where User='root';
mysql> show variables like 'character%';
+--------------------------+----------------------------+
| Variable_name | Value |
+--------------------------+----------------------------+
| character_set_client | utf8 |
| character_set_connection | utf8 |
| character_set_database | latin1 |
| character_set_filesystem | binary |
| character_set_results | utf8 |
| character_set_server | latin1 |
| character_set_system | utf8 |
| character_sets_dir | /usr/share/mysql/charsets/ |
+--------------------------+----------------------------+
 rows in set (0.01 sec)

设置数据库的编码：

mysql> exit
[root@chenguo ~]# vi /etc/my.cnf

在其中加入如下内容：

character-set-server=utf8
collation-server=utf8_general_ci
如果要修改其他的属性可以继续添加：
character-set-server=utf8
collation-server=utf8_general_ci
max_connections=
table_open_cache=
thread_cache_size=
open_files_limit=
event_scheduler=ON

group_concat_max_len=

拷贝my.cnf文件内容：

# For advice on how to change settings please see
# http://dev.mysql.com/doc/refman/5.7/en/server-configuration-defaults.html

[mysqld]
#
# Remove leading # and set to the amount of RAM for the most important data
# cache in MySQL. Start at % of total RAM for dedicated server, else %.
# innodb_buffer_pool_size = 128M
#
# Remove leading # to turn on a very important data integrity option: logging
# changes to the binary log between backups.
# log_bin
#
# Remove leading # to set options mainly useful for reporting servers.
# The server defaults are faster for transactions and fast SELECTs.
# Adjust sizes as needed, experiment to find the optimal values.
# join_buffer_size = 128M
# sort_buffer_size = 2M
# read_rnd_buffer_size = 2M
datadir=/var/lib/mysql
socket=/var/lib/mysql/mysql.sock
character-set-server=utf8
collation-server=utf8_general_ci
max_connections=
table_open_cache=
thread_cache_size=
open_files_limit=
event_scheduler=ON

group_concat_max_len=

# Disabling symbolic-links is recommended to prevent assorted security risks
symbolic-links=

log-error=/var/log/mysqld.log
pid-file=/var/run/mysqld/mysqld.pid

修改配置后需要重启mysql：

[root@chenguo ~]# systemctl stop mysqld
[root@chenguo ~]# systemctl restart mysqld

进入mysql，查看修改内容是否成功：

[root@chenguo ~]# mysql
mysql> use mysql
mysql> SHOW VARIABLES LIKE 'event_scheduler';
mysql> SHOW VARIABLES LIKE 'group_concat_max_len';

PS：当切换mysql的时候出现错误：

[root@chenguo ~]# mysql
ERROR  (): Access denied for user 'root'@'localhost' (using password: NO)

我的错误解决是直接将上面的第6步重新做一次

、命令执行完毕后，mysql就安装完成，下面需要做的就是对mysql 进行初始化
[root@chenguo bin]# cd /usr/local/bin
[root@chenguo bin]# mysqld --initialize --user=mysql
[root@chenguo bin]# mysqld --initialize-insecure --user=mysql
--18T08::.910921Z  [Warning] TIMESTAMP with implicit DEFAULT value is deprecated. Please use --explicit_defaults_for_timestamp server option (see documentation for more details).
--18T08::.912342Z  [ERROR] --initialize specified but the data directory has files in it. Aborting.
--18T08::.912368Z  [ERROR] Aborting
解决办法：
进入/var/lib/目录中查看是否有mysql目录，有的话进行删除：
[root@chenguo bin]# cd /var/lib
[root@chenguo lib]# rm -rf mysql
[root@chenguo local]# cd /usr/local/bin/
[root@chenguo bin]# mysqld --initialize-insecure --user=mysql

修改root用户密码的操作：

[root@chenguo ~]# mysql
mysql> use mysql
mysql> update user set password=PASSWORD('root') where User='root';

出现如下错误：

ERROR  (42S22): Unknown column 'password' in 'field list'

原因：mysql数据库中的user下已经没有password这个字段，而变成了authentication_string，因此修改语句为：

mysql> update user set authentication_string=PASSWORD('root') where User='root';

修改密码后，使用：

[root@chenguo ~]# systemctl stop mysqld
[root@chenguo ~]# systemctl restart mysqld

然后使用：

[root@chenguo ~]# mysql -u root -p
Enter password:

才能登录mysql。