install mysql in centos and change passoword

1- new mysql

installing mysql by mysql-server

yum install mysql-server

starting mysql

systemctl start mysqld
systemctl status mysqld

changing password for root

cat /var/log/mysqld.log|grep 'temporary password'

2016-12-01T00:22:31.416107Z 1 [Note] A temporary password is generated for root@localhost: mqRfBU_3Xk>r

mysql -u root -p

then use the password mqRfBU_3Xk>r

ALTER USER 'root'@'localhost' IDENTIFIED BY 'password'; 

given grant to root

GRANT INSERT, SELECT, DELETE, UPDATE ON *.* TO 'root'@'%';

if create a common user, below:

CREATE USER 'common'@'%' IDENTIFIED BY 'password';

2- old mysql

installing mysql locally

wget https://dev.mysql.com/get/mysql57-community-release-el7-9.noarch.rpm
md5sum mysql57-community-release-el7-9.noarch.rpm
rpm -ivh mysql57-community-release-el7-9.noarch.rpm
config && make && make install 

changing password

• edit /etc/my.conf

[mysqld]
skip-grant-tables

• inside mysql

# mysql -u root
mysql> use mysql;
mysql> update mysql.user set authentication_string=password('123') where user='root';
mysql> flush privileges;
mysql> exit