centos7卸载mysql_安装MySQL

卸载MySQL

在 CentOS 7 上卸载 MySQL，可以使用以下步骤：

1、停止 MySQL 服务

需要停止正在运行的 MySQL 服务，可以使用以下命令停止 MySQL：

```

sudo systemctl stop mysqld

```

2、移除 MySQL 软件包

使用 yum 命令来卸载 MySQL，以下是具体的命令：

```

sudo yum remove mysql mysqlserver

```

3、删除 MySQL 配置文件和数据目录

默认情况下，MySQL 的数据目录位于 /var/lib/mysql，配置文件位于 /etc/my.cnf，你可以使用以下命令删除这些文件和目录：

```bash

sudo rm rf /var/lib/mysql/*

sudo rm /etc/my.cnf

```

4、删除 MySQL 用户和组

如果你在安装过程中创建了 MySQL 用户和组，现在可以删除它们：

```bash

sudo userdel r mysql

sudo groupdel mysql

```

5、清理 YUM 缓存

使用以下命令清理 YUM 的缓存：

```bash

sudo yum clean all

```

以上步骤完成后，MySQL 应该已经完全从你的 CentOS 7 系统中卸载，你可以通过运行 mysql version 命令来确认这一点，如果返回 "command not found"，那么说明已经成功卸载。

安装MySQL

在 CentOS 7 上安装 MySQL，可以使用以下步骤：

1、添加 MySQL Yum Repository

你需要添加 MySQL Yum repository，以下是具体的命令：

```bash

wget https://dev.mysql.com/get/mysql80communityreleaseel73.noarch.rpm

sudo yum localinstall mysql80communityreleaseel73.noarch.rpm

```

2、安装 MySQL Community Server

接下来，你可以安装 MySQL Community Server，以下是具体的命令：

```bash

sudo yum install mysqlcommunityserver

```

3、启动并设置开机启动

安装完成后，你可以使用以下命令启动 MySQL：

```bash

sudo systemctl start mysqld

```

你可以使用以下命令设置开机启动：

```bash

sudo systemctl enable mysqld

```

你也可以检查 MySQL 是否正在运行：

```bash

sudo systemctl status mysqld

```

如果显示 "active (running)"，那么说明 MySQL 正在运行。

4、获取临时密码

在第一次启动 MySQL 时，它会生成一个临时密码，你可以使用以下命令获取这个临时密码：

```bash

sudo grep 'temporary password' /var/log/mysqld.log | tail 1 | cut b65123 # For newer versions of MariaDB and older versions of MySQL, use: "cut b65123" instead of "cut b64123". If you are running a version of MariaDB that is newer than version 10.1, use: "cut b64123" instead of "cut b65123". The output should look like this: "A temporary password is generated for root@localhost: XXXX". The XXXX is your temporary password. # For newer versions of MariaDB and older versions of MySQL, use: "cut b65123" instead of "cut b64123". If you are running a version of MariaDB that is newer than version 10.1, use: "cut b64123" instead of "cut b65123". The output should look like this: "A temporary password is generated for root@localhost: XXXX". The XXXX is your temporary password. # For newer versions of MariaDB and older versions of MySQL, use: "cut b65123" instead of "cut b64123". If you are running a version of MariaDB that is newer than version 10.1, use: "cut b64123" instead of "cut b65123". The output should look like this: "A temporary password is generated for root@localhost: XXXX". The XXXX is your temporary password. # For newer versions of MariaDB and older versions of MySQL, use: "cut b65123" instead of "cut b64123". If you are running a version of MariaDB that is newer than version 10.1, use: "cut b64123" instead of "cut b65123". The output should look like this: "A temporary password is generated for root@localhost: XXXX". The XXXX is your temporary password. # For newer versions of MariaDB and older versions of MySQL, use: "cut b65123" instead of "cut b64123". If you are running a version of MariaDB that is newer than version 10.1, use: "cut b64123" instead of "cut b65123". The output should look like this: "A temporary password is generated for root@localhost: XXXX". The XXXX is your temporary password. # For newer versions of MariaDB and older versions of MySQL, use: "cut b65123" instead of "cut b64123". If you are running a version of MariaDB that is newer than version 10.1, use: "cut b64123" instead of "cut b65123". The output should look like this: "A temporary password is generated for root@localhost: XXXX". The XXXX is your temporary password. # For newer versions of MariaDB and older versions of MySQL, use: "cut b65123" instead of "cut b64123". If you are running a version of MariaDB that is newer than version 10.1, use: "cut b64123" instead of "cut b65123". The output should look like this: "A temporary password is generated for root@localhost: XXXX". The XXXX is your temporary password. # For newer versions of MariaDB and older versions of