centos7 安裝mariadb
一、使用國內源：
mv /etc/yum.repos.d/CentOS-Base.repo /etc/yum.repos.d/CentOS-
Base.repo.backup
wget -O /etc/yum.repos.d/CentOS-Base.repo
http://mirrors.aliyun.com/repo/Centos-7.repo
二、安裝mariadb
yum -y install mariadb mariadb-server mariadb-devel
三、cat /etc/my.cnf
[mysqld]default-storage-engine = innodb
innodb_file_per_table
collation-server = utf8_general_ci
init-connect = 'SET NAMES utf8'
character-set-server = utf8
四、啓動mariadb
root用戶直接啓動，由於我的環境是vagrant ssh連接的，默認的是vagrant用戶
systemctl start mariadb #用root用戶啓動，非root用戶需要sudo
mysql進入mariadb：
Welcome to the MariaDB monitor. Commands end with ; or \g.
Your MariaDB connection id is 4
Server version: 5.5.56-MariaDB MariaDB Server
Copyright (c) 2000, 2017, Oracle, MariaDB Corporation Ab and others.
Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.
MariaDB [(none)]> show databases;
+--------------------+
| Database |
+--------------------+
| information_schema |
| test |
+--------------------+
2 rows in set (0.00 sec)
MariaDB [(none)]> select * from mysql.user \G
ERROR 1142 (42000): SELECT command denied to user ''@'localhost' for table 'user'
#這裏就2個庫，mysql庫看不到，當然也查看不了
MariaDB [(none)]> select user();
+-------------------+
| user() |
+-------------------+
| vagrant@localhost |
+-------------------+
1 row in set (0.00 sec)
#看到 當前登錄的用戶是，因爲剛纔是mysql 直接進來的，此時我們要給mariadb配置初始密碼；
mysqladmin -u root password #設置root密碼。
再來，這次不直接mysql進來了
mysql -uroot -p
這裏輸入剛纔的密碼
進來了
MariaDB [(none)]> show databases;
+--------------------+
| Database |
+--------------------+
| information_schema |
| mysql |
| performance_schema |
| test |
+--------------------+
4 rows in set (0.00 sec)
MariaDB [(none)]> select * from mysql.user \G 正常查詢
忘記root密碼：
- systemctl stop mariadb 先關閉服務
- su - root 切到系統root用戶
- mysqld_safe --skip-grant-tables & 跳過認證啓動服務
- mysql mysql進入服務
- use mysql 切換到mysql庫
- UPDATE user SET password=password('heheda') WHERE user='root';
- flush privileges;
- ps -ef |grep mysql|grep -v grep |awk '{print $2}'|xargs kill -9
- systemctl start mariadb