CentOS 7 安裝MySQL8

安裝

下載Linux對應的MySQL https://dev.mysql.com/downloads/mysql/node

CentOS選擇Red Hat Enterprise Linuxmysql
在/usr/local/目錄下新建目錄mysqlsql
```
cd /usr/local/
 mkdir mysql
 cd mysql/
```

打開文件傳輸工具將下載的壓縮包 mysql-8.0.17-1.el7.x86_64.rpm-bundle.tar 放到此目錄解壓 tar -xvf mysql-8.0.17-1.el7.x86_64.rpm-bundle.tar數據庫

解壓出來8個文件vim

mysql-community-client-8.0.17-1.el7.x86_64.rpm
 mysql-community-common-8.0.17-1.el7.x86_64.rpm
 mysql-community-devel-8.0.17-1.el7.x86_64.rpm
 mysql-community-embedded-compat-8.0.17-1.el7.x86_64.rpm
 mysql-community-libs-8.0.17-1.el7.x86_64.rpm
 mysql-community-libs-compat-8.0.17-1.el7.x86_64.rpm
 mysql-community-server-8.0.17-1.el7.x86_64.rpm
 mysql-community-test-8.0.17-1.el7.x86_64.rpm

檢查是否有預裝數據庫mariadb rpm -qa | grep mariadb 及是否預裝mysql運維

檢測出來了就移除 rpm -e mariadb-libs-..... --nodeps 根據檢查出來的名字輸入tcp
安裝ide
- 安裝 common rpm -ivh mysql-community-common-8.0.17-1.el7.x86_64.rpm --nodeps --force工具
- 安裝 libs rpm -ivh mysql-community-libs-8.0.17-1.el7.x86_64.rpm --nodeps --forceurl
- 安裝 client rpm -ivh mysql-community-client-8.0.17-1.el7.x86_64.rpm --nodeps --force
- 安裝 server rpm -ivh mysql-community-server-8.0.17-1.el7.x86_64.rpm --nodeps --force
- 查看已安裝的包 rpm -qa | grep mysql
```
[root@izuf63okxpwhhlr3bu263dz mysql]# rpm -qa | grep mysql
  mysql-community-libs-8.0.17-1.el7.x86_64
  mysql-community-server-8.0.17-1.el7.x86_64
  mysql-community-common-8.0.17-1.el7.x86_64
  mysql-community-client-8.0.17-1.el7.x86_64
```

初始化

經過一下命令完成mysql初始化

mysqld --initialize

若是報以下錯誤信息：

mysqld:error while loading shared libraries: libaio.so.1: cannot open shared object file: No shch file or directory

則安裝下 libaio.so.1 包

# 方案1
  yum install -y libaio

  # 方案2，若是方案1安裝後，繼續初始化mysql沒成功，則執行該方案
  yum install -y libaio.so.1

受權服務

# 給mysql目錄受權，通常不用操做，root用戶擁有全部權限
  chown mysql:mysql /var/lib/mysql -R;

  # 啓動mysql服務
  systemctl start mysqld.service;

  # 配置開機啓動
  systemctl enable mysqld;

查看數據庫默認密碼 cat /var/log/mysqld.log | grep password

[root@izuf63okxpwhhlr3bu263dz mysql]# cat /var/log/mysqld.log | grep password
  2019-10-07T08:45:06.207436Z 5 [Note] [MY-010454] [Server] A temporary password is generated for root@localhost: gfn,!V/j7tlz

拿到查詢出的密碼進行數據庫的登陸 mysql -u root -p gfn,!V/j7tlz
修改默認密碼 alter user 'root'@'localhost' identified with mysql_native_password by 'root'; 修改後退出以修改後的密碼從新登陸

受權遠程訪問

create user 'root'@'%' identified with mysql_native_password by '123456';
  grant all privileges on *.* to 'root'@'%' with grant option;
  flush privileges;

此時採用Navicat等可視化客戶端可能沒法鏈接，由於端口未對外開放

防火牆配置

# 查看防火牆狀態
 systemctl status firewalld

 # 啓動防火牆，防火牆啓動後，除了22端口對外可以訪問，其餘端口軍不能使用，因此須要添加
 systemctl start firewalld

 # 添加端口
 firewall-cmd --zone=public --add-port=80/tcp --permanent
 firewall-cmd --zone=public --add-port=443/tcp --permanent
 firewall-cmd --zone=public --add-port=3306/tcp --permanent

 # 從新加載
 firewall-cmd --reload

其餘
- 查看MySQL配置文件
```
# 默認的配置文件爲： /etc/my.cnf
  cat /etc/my.cnf
```
- 查看進程語句 ps -ef | grep mysql

大功告成

遺留問題

Linux下的MySQL數據庫大小寫敏感，因此SQL語句中的表名區分大小寫

忽略大小寫配置

$ vim /etc/my.cnf
  [mysqld]
  lower_case_table_names=1

可是在MySQL8 這樣不行，網上有說要在初始化的時候設置纔有效 --initialize --lower-case-table-names=1 可是我怎麼試也不行，只要啓動服務就報錯

[root@izuf63okxpwhhlr3bu263dz mysql]# systemctl start mysqld.service;
    Job for mysqld.service failed because the control process exited with error code. See "systemctl status mysqld.service" and "journalctl -xe" for details.

折騰半天只好讓它大小寫敏感去吧，反正我也不是運維

卸載

關閉mysql服務

[root@izuf63okxpwhhlr3bu263dz mysql]# service mysqld stop
 Redirecting to /bin/systemctl stop  mysqld.service

查看安裝的mysql

[root@izuf63okxpwhhlr3bu263dz mysql]# rpm -qa | grep -i mysql
 mysql-community-libs-8.0.17-1.el7.x86_64
 mysql-community-server-8.0.17-1.el7.x86_64
 mysql-community-common-8.0.17-1.el7.x86_64
 mysql-community-client-8.0.17-1.el7.x86_64

卸載列出來的全部mysql

rpm -ev mysql-community-......... --nodeps

刪除mysql相關

find / -name mysql
 rm -rf /var/lib/mysql/
 ......

刪除my.cnf

rm -rf /etc/my.cnf
檢查卸載狀況

rpm -qa|grep -i mysql

爲空，大功告成