mysql 二进包在linux下安装过程
cp mysql-5.6.17-linux-glibc2.5-i686 /usr/local/mysql -r
groupadd mysql和useradd -r -g mysql mysql
进入安装mysql软件目录：执行命令 cd /usr/local/mysql
修改当前目录拥有者为mysql用户：执行命令 chown -R mysql:mysql ./
./scripts/mysql_install_db --basedir=/usr/local/mysql --datadir=/usr/local/mysql/data --user=mysql
修改当前目录拥有者为root用户：执行命令 chown -R root:root ./
修改当前data目录拥有者为mysql用户：执行命令 chmod -R 755 /usr/local/mysql/data chmod -R 755 /usr/local/mysql/data/mysql
cp support-files/mysql.server /etc/init.d/mysql
service mysql start
mysqladmin -u root password '密码'
--连接myql后在mysql提示符下执行以下语句
GRANT ALL PRIVILEGES ON *.* TO 'root'@'%' IDENTIFIED BY 'root' WITH GRANT OPTION;
flush privileges;
rpm包的安装过程如下：
第一步：官网上下载安装包mysql-5.7.28-1.el7.x86_64.rpm-bundle.tar ，下载地址 https://downloads.mysql.com/archives/community/
第二步：解压 tar -xvf mysql-5.7.28-1.el7.x86_64.rpm-bundle.tar ，得到如下文件：
mysql-community-embedded-compat-5.7.28-1.el7.x86_64.rpm
mysql-community-embedded-devel-5.7.28-1.el7.x86_64.rpm
mysql-community-client-5.7.28-1.el7.x86_64.rpm
mysql-community-libs-5.7.28-1.el7.x86_64.rpm
mysql-community-common-5.7.28-1.el7.x86_64.rpm
mysql-community-libs-compat-5.7.28-1.el7.x86_64.rpm
mysql-community-devel-5.7.28-1.el7.x86_64.rpm
mysql-community-server-5.7.28-1.el7.x86_64.rpm
mysql-community-embedded-5.7.28-1.el7.x86_64.rpm
mysql-community-test-5.7.28-1.el7.x86_64.rpm
第三步：执行rpm -ivh mysql-community-common-5.7.28-1.el7.x86_64.rpm 安装，如果出现以下错误，
则说明当前 linux系统上有默认安装，需要先卸载 , 先执行 rpm -qa | grep mariadb 查询出要卸载的包，
rpm -e mariadb-libs-5.5.41-2.el7_0.x86_64 删除，会报如下错：
error: Failed dependencies:
libmysqlclient.so.18()(64bit) is needed by (installed) postfix-2:2.10.1-6.el7.x86_64
libmysqlclient.so.18(libmysqlclient_18)(64bit) is needed by (installed) postfix-2:2.10.1-6.el7.x86_64
说明存在依赖关系，强制卸载
rpm -e --nodeps mariadb-libs-5.5.41-2.el7_0.x86_64
第四步：安装mysql-community-client包，rpm -ivh mysql-community-client-5.7.21-1.el7.x86_64.rpm，出现以下错误：
warning: mysql-community-client-5.7.21-1.el7.x86_64.rpm: Header V3 DSA/SHA1 Signature, key ID 5072e1f5: NOKEY
error: Failed dependencies:
mysql-community-libs(x86-64) >= 5.7.9 is needed by mysql-community-client-5.7.21-1.el7.x86_64
根据提示先安装 mysql-community-libs包 rpm -ivh mysql-community-libs-5.7.21-1.el7.x86_64.rpm，然后再尝试尝试安装mysql-client
第五步：安装mysql-server
rpm -ivh mysql-community-server-5.7.21-1.el7.x86_64.rpm
第六步：查看mysql的服务 systemctl status mysqld.service
mysqld.service - MySQL Server
Loaded: loaded (/usr/lib/systemd/system/mysqld.service; enabled)
Active: inactive (dead)
Docs: man:mysqld(8)
http://dev.mysql.com/doc/refman/en/using-systemd.html
第七步：启动mysql服务 systemctl start mysqld.service
第八步：查看临时密码 grep "password" /var/log/mysqld.log
[root@hadoop software]# grep "password" /var/log/mysqld.log 2020-02-14T11:26:05.038127Z 1 [Note] A temporary password is generated for root@localhost: !<kiTH=DZ53o
第九步：使用临时密码登录，然后修改root的密码
mysql -uroot -p
第十步：修改root密码：
mysql> ALTER USER 'root'@'localhost' IDENTIFIED BY 'hangzhou123';
ERROR 1819 (HY000): Your password does not satisfy the current policy requirements
报错的原因：其实与validate_password_policy的值有关。默认是1，即MEDIUM，所以刚开始设置的密码必须符合长度，且必须含有数字，小写或大写字母，特殊字符。
解决方法：
修改validate_password_policy参数的值
mysql> set global validate_password_policy=0;
mysql> ALTER USER 'root'@'localhost' IDENTIFIED BY 'hangzhou';
mysql> select @@validate_password_length;
+----------------------------+
| @@validate_password_length |
+----------------------------+
| 8 |
+----------------------------+
1 row in set (0.05 sec)
第十一步：使用新密码再次登录，登录成功
mysql -uroot -phangzhou
以上安装没想到如此麻烦，还好网上找到一篇文章，以上基本参考此文完成：http://blog.itpub.net/31015730/viewspace-2152272/
