centos7安裝mysql，以及設置root密碼

1.首先進入mysql官網的下載-社區https://dev.mysql.com/downloads/

 2.點擊下載后，切換版本5.7選擇yum下載鏈接

 3.在新打開的頁面，點擊下載rpm文件，在新的頁面選擇直接下載，獲取到下載鏈接

4.移除mariadb數據庫

yum remove mariadb-libs.x86_64

5.進入到/tmp目錄使用wget下載上面得到的連接

wget https://repo.mysql.com//mysql80-community-release-el7-2.noarch.rpm

6.安裝mysql的源

yum localinstall mysql80-community-release-el7-2.noarch.rpm 

7.通過查找命令找到社區版的安裝文件

yum search mysql

另外，安裝yum-config-manager，然后修改要安裝的mysql版本為5.7

[root@freesaber tmp]# yum search yum-config-manager
Loaded plugins: fastestmirror
Loading mirror speeds from cached hostfile
========================================== Matched: yum-config-manager ==========================================
yum-utils.noarch : Utilities based around the yum package manager
[root@freesaber tmp]# yum install yum-utils.noarch

yum-config-manager --disable mysql80-community
yum-config-manager --enable mysql57-community

8.安裝mysql

yum install mysql-community-server

9.開啟mysql服務

systemctl start mysqld

10.查看myqsl的默認密碼

 cat /var/log/mysqld.log

2019-03-27T03:05:34.627566Z 0 [System] [MY-013169] [Server] /usr/sbin/mysqld (mysqld 8.0.15) initializing of server in progress as process 29114
2019-03-27T03:05:38.631106Z 5 [Note] [MY-010454] [Server] A temporary password is generated for root@localhost: I+w=67d;+ES8
2019-03-27T03:05:40.427422Z 0 [System] [MY-013170] [Server] /usr/sbin/mysqld (mysqld 8.0.15) initializing of server has completed
2019-03-27T03:05:42.371036Z 0 [System] [MY-010116] [Server] /usr/sbin/mysqld (mysqld 8.0.15) starting as process 29161
2019-03-27T03:05:43.074650Z 0 [Warning] [MY-010068] [Server] CA certificate ca.pem is self signed.
2019-03-27T03:05:43.117341Z 0 [System] [MY-010931] [Server] /usr/sbin/mysqld: ready for connections. Version: '8.0.15'  socket: '/var/lib/mysql/mysql.sock'  port: 3306  MySQL Community Server - GPL.
2019-03-27T03:05:43.166968Z 0 [System] [MY-011323] [Server] X Plugin ready for connections. Socket: '/var/run/mysqld/mysqlx.sock' bind-address: '::' port: 33060

11.使用密碼進行登陸mysql

 mysql -uroot -p

12.修改設置密碼的驗證規則

set global validate_password_policy=0;

set global validate_password_length=1;

13.修改root的密碼

mysql>  SET PASSWORD = PASSWORD('密碼');
Query OK, 0 rows affected, 1 warning (0.00 sec)

14.退出后，使用新密碼登陸。查看數據庫。

mysql -u root -p

mysql> show databases;
+--------------------+
| Database           |
+--------------------+
| information_schema |
| mysql              |
| performance_schema |
| sys                |
+--------------------+
4 rows in set (0.00 sec) 

15.查看root賬戶，修改root賬戶，允許任何主機進行連接

mysql> use mysql;
Database changed
mysql> select Host,User from user \G;
*************************** 1. row ***************************
Host: localhost
User: mysql.infoschema
*************************** 2. row ***************************
Host: localhost
User: mysql.session
*************************** 3. row ***************************
Host: localhost
User: mysql.sys
*************************** 4. row ***************************
Host: localhost User: root
4 rows in set (0.00 sec)

mysql> update user set Host = '%' where Host = 'localhost' and User = 'root';
Query OK, 1 row affected (0.04 sec)
Rows matched: 1  Changed: 1  Warnings: 0

mysql> select Host,User from user \G;
*************************** 1. row ***************************
Host: % User: root
*************************** 2. row ***************************
Host: localhost
User: mysql.infoschema
*************************** 3. row ***************************
Host: localhost
User: mysql.session
*************************** 4. row ***************************
Host: localhost
User: mysql.sys
4 rows in set (0.00 sec)

ERROR: 
No query specified

刷新權限

FLUSH PRIVILEGES;

16.使用Navicat連接mysql(需要關閉firewalld服務，另外阿里雲的安全組需要允許訪問3306)

systemctl stop firewalld

17.開啟genelog

mysql> set global general_log_file="/tmp/general.log";
Query OK, 0 rows affected (0.00 sec)

mysql> set global general_log=on;
Query OK, 0 rows affected (0.00 sec)