[root@localhost ~]# rpm -qa | grep mariadb
mariadb-libs-5.5.56-2.el7.x86_64
[root@localhost ~]# rpm -e --nodeps mariadb-libs-5.5.56-2.el7.x86_64

[root@localhost ~]# groupadd mysql
[root@localhost ~]# useradd -r -g mysql -s /bin/false mysql

[root@localhost ~]# mkdir -p /app/data
[root@localhost ~]# chown mysql.mysql /app/data/
[root@localhost ~]# chmod 750 /app/data

[root@localhost ~]# tar xvf mysql-5.7.28-linux-glibc2.12-x86_64.tar.gz -C /usr/local/
root@localhost ~]# cd /usr/local
[root@localhost local]# ln -sv mysql-5.7.28-linux-glibc2.12-x86_64 mysql
‘mysql' -> ‘mysql-5.7.28-linux-glibc2.12-x86_64'

[root@localhost ~]# cd /usr/local/mysql
[root@localhost mysql]# bin/mysqld --initialize --user=mysql --basedir=/usr/local/mysql --datadir=/app/data
2019-11-03T09:47:18.263716Z 0 [Warning] TIMESTAMP with implicit DEFAULT value is deprecated. Please use --explicit_defaults_for_timestamp server option (see documentation for more details).
2019-11-03T09:47:19.059462Z 0 [Warning] InnoDB: New log files created, LSN=45790
2019-11-03T09:47:19.140866Z 0 [Warning] InnoDB: Creating foreign key constraint system tables.
2019-11-03T09:47:19.207569Z 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: ed1cd8ec-fe1e-11e9-8c9c-000c29f8617a.
2019-11-03T09:47:19.209181Z 0 [Warning] Gtid table is not ready to be used. Table 'mysql.gtid_executed' cannot be opened.
2019-11-03T09:47:19.646366Z 0 [Warning] CA certificate ca.pem is self signed.
2019-11-03T09:47:20.056792Z 1 [Note] A temporary password is generated for root@localhost: rY-6f??#!<zO

[root@localhost mysql]# bin/mysql_ssl_rsa_setup
2019-11-03 23:09:55 [ERROR]  Failed to access directory pointed by --datadir. Please make sure that directory exists and is accessible by mysql_ssl_rsa_setup. Supplied value : /usr/local/mysql/data
[root@localhost mysql]# bin/mysql_ssl_rsa_setup --datadir=/app/data

[root@localhost mysql]# vim /etc/my.cnf
[mysqld]
# GENERAL
datadir=/app/data
socket=/app/data/mysql.sock
user=mysql
default-storage-engine=InnoDB

[mysqld_safe]
log-error=/app/data/mysql-error.log
pid-file=/app/data/mysqld.pid

[client]
socket=/app/data/mysql.sock

[root@localhost mysql]# bin/mysqld_safe --user=mysql &

[root@localhost ~]# vim /etc/profile
#添加下面一行
export PATH=$PATH:/usr/local/mysql/bin
[root@localhost ~]# source /etc/profile

[root@localhost mysql]# cp support-files/mysql.server /etc/init.d/mysql.server
[root@localhost mysql]# chkconfig --add mysql.server

[root@localhost ~]# mysql -uroot -p
Enter password:
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 2
Server version: 5.7.28

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