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https://mariadb.com/kb/en/mariadb-package-repository-setup-and-usage/
curl -LsS https://downloads.mariadb.com/MariaDB/mariadb_repo_setup | sudo bash -s -- --mariadb-server-version="mariadb-10.3"
yum install MariaDB-server MariaDB-client MariaDB-backup
service mariadb start
mysql_secure_installation
初始化数据库设置