本文将介绍在 Centos7 版本中安装 MySQL 免安装版本。
使用浏览器访问 mysql 官网，获取 mysql 安装包的下载地址：
https://cdn.mysql.com/archives/mysql-5.7/mysql-5.7.35-el7-x86_64.tar.gz
（1）使用 wget 命令下载，如下：
[root@localhost ~]# wget https://cdn.mysql.com/archives/mysql-5.7/mysql-5.7.35-el7-x86_64.tar.gz --2021-11-05 13:01:34-- https://cdn.mysql.com/archives/mysql-5.7/mysql-5.7.35-el7-x86_64.tar.gz Resolving cdn.mysql.com (cdn.mysql.com)... 104.107.242.188 Connecting to cdn.mysql.com (cdn.mysql.com)|104.107.242.188|:443... connected. HTTP request sent, awaiting response... 200 OK Length: 732374542 (698M) [application/x-tar-gz] Saving to: ‘mysql-5.7.35-el7-x86_64.tar.gz.1’ 100%[======================================>] 732,374,542 3.34MB/s in 3m 21s 2021-11-05 13:04:56 (3.47 MB/s) - ‘mysql-5.7.35-el7-x86_64.tar.gz’ saved [732374542/732374542]
注意：mysql 安装包大小为 600+MB，需要等待一会儿。
（2）成功下载 mysql 安装包后，使用 tar 命令解压安装包，如下：
[root@localhost ~]# tar -xvzf mysql-5.7.35-el7-x86_64.tar.gz mysql-5.7.35-el7-x86_64/bin/myisam_ftdump ... mysql-5.7.35-el7-x86_64/docs/INFO_BIN mysql-5.7.35-el7-x86_64/docs/INFO_SRC
（3）使用 mv 命令将解压后的目录重命名为 “mysql”，如下：
[root@localhost ~]# mv mysql-5.7.35-el7-x86_64 mysql
（4）使用 mv 命令将重命名后的 mysql 移动到 /usr/local/ 目录，如下：
[root@localhost ~]# sudo mv mysql /usr/local/ [root@localhost ~]# ls /usr/local/mysql/ bin docs include lib LICENSE man README share support-files
（1）配置 my.cnf 文件，将 mysql 的 support-files 目录下的 my.cnf 文件复制到 /etc/my.cnf。mysql 5.7 之后support-files 目录下没有 my.cnf 文件，所以直接创建 /etc/my.cnf 文件。my.cnf 文件内容如下：
[mysqld] basedir=/usr/local/mysql datadir=/usr/local/mysql/data socket=/usr/local/mysql/mysql.sock # Disabling symbolic-links is recommended to prevent assorted security risks symbolic-links=0 # Settings user and group are ignored when systemd is used. # If you need to run mysqld under a different user or group, # customize your systemd unit file for mariadb according to the # instructions in http://fedoraproject.org/wiki/Systemd [mysqld_safe] log-error=/var/log/error.log pid-file=/usr/local/mysql/data/mysqld.pid [client] socket=/usr/local/mysql/mysql.sock default-character-set=utf8
（2）创建 mysql 数据目录，如下：
[root@localhost ~]# cd /usr/local/ [root@localhost local]# mkdir data [root@localhost local]# ll total 0 drwxr-xr-x. 2 root root 6 Apr 11 2018 bin drwxr-xr-x. 2 root root 6 Nov 5 13:18 data drwxr-xr-x. 2 root root 6 Apr 11 2018 etc drwxr-xr-x. 2 root root 6 Apr 11 2018 games drwxr-xr-x. 2 root root 6 Apr 11 2018 include drwxr-xr-x. 2 root root 6 Apr 11 2018 lib drwxr-xr-x. 2 root root 6 Apr 11 2018 lib64 drwxr-xr-x. 2 root root 6 Apr 11 2018 libexec drwxr-xr-x. 11 root root 151 Oct 1 06:53 nginx drwxr-xr-x. 2 root root 6 Apr 11 2018 sbin drwxr-xr-x. 5 root root 49 Aug 3 01:28 share drwxr-xr-x. 2 root root 6 Apr 11 2018 src
（3）出于安全和便利，创建一个专门操作数据库的用户。如下：
a、建立一个 mysql 组
[root@localhost mysql]# groupadd mysql
b、建立 mysql 用户，并且把用户放到 mysql 组
[root@localhost mysql]# useradd -r -g mysql mysql
c、将目录 /usr/local/mysql 拥有者改为 mysql
[root@localhost mysql]# chown -R mysql:mysql /usr/local/mysql/ [root@localhost mysql]# ll total 272 drwxr-xr-x. 2 mysql mysql 4096 Nov 5 13:00 bin drwxr-xr-x. 2 mysql mysql 6 Nov 5 13:22 data drwxr-xr-x. 2 mysql mysql 55 Nov 5 13:00 docs drwxr-xr-x. 3 mysql mysql 4096 Nov 5 12:59 include drwxr-xr-x. 5 mysql mysql 230 Nov 5 13:00 lib -rw-r--r--. 1 mysql mysql 259200 Jun 7 20:52 LICENSE drwxr-xr-x. 4 mysql mysql 30 Nov 5 13:00 man -rw-r--r--. 1 mysql mysql 566 Jun 7 20:52 README drwxr-xr-x. 28 mysql mysql 4096 Nov 5 13:00 share drwxr-xr-x. 2 mysql mysql 90 Nov 5 13:00 support-files
使用 mysql 的 “mysqld --initialize” 命令初始化 mysql 数据库，如下：
[root@localhost bin]# ./mysqld --initialize --user=mysql --basedir=/usr/local/mysql --datadir=/usr/local/mysql/data 2021-11-05T05:24:20.044232Z 0 [Warning] TIMESTAMP with implicit DEFAULT value is deprecated. Please use --explicit_defaults_for_timestamp server option (see documentation for more details). 2021-11-05T05:24:20.248550Z 0 [Warning] InnoDB: New log files created, LSN=45790 2021-11-05T05:24:20.286955Z 0 [Warning] InnoDB: Creating foreign key constraint system tables. 2021-11-05T05:24:20.348752Z 0 [Warning] No existing UUID has been found, so we assume that this is the first time that this server has been started. Generating a new UUID: a0f8d057-3df8-11ec-b3cb-000c29633905. 2021-11-05T05:24:20.349623Z 0 [Warning] Gtid table is not ready to be used. Table 'mysql.gtid_executed' cannot be opened. 2021-11-05T05:24:21.488386Z 0 [Warning] A deprecated TLS version TLSv1 is enabled. Please use TLSv1.2 or higher. 2021-11-05T05:24:21.488406Z 0 [Warning] A deprecated TLS version TLSv1.1 is enabled. Please use TLSv1.2 or higher. 2021-11-05T05:24:21.489119Z 0 [Warning] CA certificate ca.pem is self signed. 2021-11-05T05:24:21.778522Z 1 [Note] A temporary password is generated for root@localhost: 0hrhgOkuq1%1
注意：上面初始化 mysql 最后输出的 “0hrhgOkuq1%1” 为 mysql 默认密码。
[root@localhost bin]# ./mysqld_safe --user=mysql & [1] 23488 2021-11-05T05:26:38.297282Z mysqld_safe Logging to '/var/log/error.log'. 2021-11-05T05:26:38.352368Z mysqld_safe Starting mysqld daemon with databases from /usr/local/mysql/data
（1）使用 mysql 客户端工具连接到 mysql 客户端（这里使用上面初始化 mysql 生成的密码 0hrhgOkuq1%1），如下：
[root@localhost bin]# ./mysql -uroot -p Enter password: Welcome to the MySQL monitor. Commands end with ; or \g. Your MySQL connection id is 2 Server version: 5.7.35 Copyright (c) 2000, 2021, Oracle and/or its affiliates. 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>
（2）初次登录 mysql 需要修改密码，如下：
mysql> set password=password('aaaaaa');
Query OK, 0 rows affected, 1 warning (0.00 sec)（3）演示 mysql 的 show、use、select 语句，如下：
mysql> show databases; +--------------------+ | Database | +--------------------+ | information_schema | | mysql | | performance_schema | | sys | +--------------------+ 4 rows in set (0.00 sec) mysql> use mysql; Reading table information for completion of table and column names You can turn off this feature to get a quicker startup with -A Database changed mysql> use mysql Database changed mysql> select Host,User from user; +-----------+---------------+ | Host | User | +-----------+---------------+ | localhost | mysql.session | | localhost | mysql.sys | | localhost | root | +-----------+---------------+ 3 rows in set (0.00 sec)
