mariadb

安装数据库
yum install mariadb-server.x86_64 -y
yum whatprovides */mysql ##查找软件包
yum install mariadb-5.5.35-3.el7.x86_64 -y
vim /etc/my.cnf

[mysqld]datadir=/var/lib/mysqlsocket=/var/lib/mysql/mysql.sock# Disabling symbolic-links is recommended to prevent assorted security riskssymbolic-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 http://fedoraproject.org/wiki/Systemdskip-networking=1     ###防止其他用户登录数据库[mysqld_safe]log-error=/var/log/mariadb/mariadb.logpid-file=/var/run/mariadb/mariadb.pid..............

systemctl start mariadb

设置密码
mysql_secure_installation
mysql -uroot -p

1.查询
SHOW DATABASES;
USE database_name;
SHOW TABLES;
DESC table_name;
SELECT * FROM table_name;
SELECT * FROM table_name WHERE attribute =‘value’;

2.创建
CREATE DATABASE database_name;
CREATE TABLE table_name (name VARCHAR(20), sex CHAR(1));
DESCRIBE table_name;
INSERT INTO table_name VALUES (‘wxh’,’M’);

3.修改
ALTER TABLE table_name RENAME table_name_another;
ALTER TABLE table_name_another ADD class VARCHAR(20);
ALTER TABLE table_name_another ADD age VARCHAR(20) AFTER name;
UPDATE table_name SET attribute= ‘value’;
UPDATE table_name SET attribute= ‘value’ WHERE attribute > ‘value’;

4.删除
DELETE FROM table_name WHERE attribute = ‘value’;
DROP TABLE table_name;
DROP DATABASE database_name;

5.备份

 mysqldump -uroot -predhat westos > westos.sql mysqldump -uroot -predhat --all-databases > backup.sql mysqldump -uroot -predhat --no-data westos > westos.sql

6.恢复
DROP DATABASE westos;
mysql -uroot -predhat -e “CREATE DATABASE westos;”
mysql -uroot -predhat westos < westos.sql

忘了数据库密码怎么办?
vim /etc/my.cnf

mysqld_safe --skip-grant-tables &

UPDATE user SET Password=’redhat’ WHERE User=’root’;
systemctl stop mariadb / kill -9 干掉mysql有关的进程
systemctl restart mariadb
mysql -u root -predhat