mysql> show global variables like 'port'; 是0

打开目录

/etc/mysql/mysql.conf.d

修改这段话为

[mysqld]
#
# * Basic Settings
#
user            = mysqlpid-file       = /var/run/mysqld/mysqld.pidsocket = /var/run/mysqld/mysqld.sockport           = 3306datadir        = /var/lib/mysql#skip-grant-tables
# If MySQL is running as a replication slave, this should be
# changed. Ref https://dev.mysql.com/doc/refman/8.0/en/server-system-variables.html#sysvar_tmpdir
# tmpdir                = /tmp
#
# Instead of skip-networking the default is now to listen only on
# localhost which is more compatible and is not less secure.
bind-address            = 127.0.0.1
mysqlx-bind-address     = 127.0.0.1

其中skip-grant-tables 这个应该是免密码登录，给注释掉，我也不知道为什么跟端口0相关

然后重启数据库

systemctl restart mysql
然后 

登录数据库

mysql -uroot -p 123456 1234456是我的密码

然后查看 

 netstat -lanp | grep 3306
tcp        0      0 127.0.0.1:33060         0.0.0.0:*               LISTEN      122309/mysqld       
tcp        0      0 127.0.0.1:3306          0.0.0.0:*               LISTEN      122309/mysqld  

启动成功 为什么还有个33060不知道