pare-db-dir %n (code=exited, status=0/SUCCESS)
Main PID: 9549 (code=exited, status=0/SUCCESS)
Jan 19 12:49:06 console systemd[1]: Starting MariaDB database server...
Jan 19 12:49:06 console mariadb-prepare-db-dir[9517]: Database MariaDB is probably initialized in /var/lib/mysql alre
Jan 19 12:49:06 console mariadb-prepare-db-dir[9517]: If this is not the case, make sure the /var/lib/mysql is empty
Jan 19 12:49:06 console mysqld_safe[9549]: 190119 12:49:06 mysqld_safe Logging to '/var/log/mariadb/mariadb.log'.
Jan 19 12:49:06 console mysqld_safe[9549]: 190119 12:49:06 mysqld_safe Starting mysqld daemon with databases from /va
Jan 19 12:49:08 console systemd[1]: mariadb.service: control process exited, code=exited status=1
Jan 19 12:49:08 console systemd[1]: Failed to start MariaDB database server.
Jan 19 12:49:08 console systemd[1]: Unit mariadb.service entered failed state.
Jan 19 12:49:08 console systemd[1]: mariadb.service failed.
解决方式：
（1）修改配置文件：
添加参数：
innodb_force_recovery = 6 （此项由1---6个级别一次往上修改参数在失败的情况下）
innodb_purge_threads = 0
（2）修改刚才解压的文件属主属组为mysql用户。
我的数据库配置文件：
[mysqld]
datadir=/var/lib/mysql
socket=/var/lib/mysql/mysql.sock
lower_case_table_name=1
character_set_server=utf8
skip_name_resolve
bind-address = 0.0.0.0
innodb_force_recovery = 6
innodb_purge_threads = 0
# 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 https://fedoraproject.org/wiki/Systemd
[mysqld_safe]
log-error=/var/log/mariadb/mariadb.log
pid-file=/var/run/mariadb/mariadb.pid
#
# include all files from the config directory
#
!includedir /etc/my.cnf.d