How to modify the password of MySQL 5.1 and remotely log in to the MySQL database

mysql> grant all on book.* to mk1@localhost identified by "123456";
 #Allow access to all tables under the book database. Only book tables can be accessed, and users on the same server

mysql> grant all privileges on *.* to mk2@'%' identified by '123456' with grant option;
# with grant option means that the mk2 user can delegate his own permissions to the newly created user. In addition, you can add or not add privileges. % refers to any remote host, excluding local addresses and localhost
Flush privileges; Refresh the database

[root@xuegod64 ~]# mysql -u mk2 -h 192.168.1.63 -p123456
mysql> #Login is normal

[root@xuegod63 ~]# mysql -u mk2 -h 192.168.1.63 -p123456 #Cannot log in

mysql> grant all privileges on *.* to 'mk2'@'192.168.1.63' identified by '123456' with grant option;
 [root@xuegod63 ~]# mysql -u mk2 -p123456 #Cannot log in

mysql> grant all privileges on *.* to 'mk2'@'localhost' identified by '123456' with grant option;

mysql> grant select,insert,update,delete,create,drop on aa.* to 'custom'@'localhost' identified by '123456';

mysql> use mysql;
mysql> insert into user (Host,User,Password) values('localhost','grace','123456');
mysql> select Host,User,Password from user where User="grace";
+-----------+-------+----------+
| Host | User | Password |
+-----------+-------+----------+
| localhost | grace | 123456 |
+-----------+-------+----------+

mysql> insert into user (Host,User,Password) values('localhost','grace1',password("123456"));
Query OK, 1 row affected, 3 warnings (0.00 sec)
mysql> select Host,User,Password from user where User="grace1";
+-----------+--------+-------------------------------------------+
| Host | User | Password |
+-----------+--------+-------------------------------------------+
| localhost | grace1 | *6BB4837EB74329105EE4568DDA7DC67ED2CA2AD9 |
+-----------+--------+-------------------------------------------+
1 row in set (0.01 sec)
mysql> flush privileges; #Refresh the privilege table to make the configuration file effective

[root@xuegod63 ~]# service mysqld restart

[root@xuegod63 ~]# mysql -u grace -p123456 #Login failed ERROR 1045 (28000): Access denied for user 'grace'@'localhost' (using password: YES)
[root@xuegod63 ~]# mysql -u grace1 -p123456 #Login successful

[root@xuegod63 mysql]# mysqladmin -u root -h 192.168.1.63 password '123'
[root@xuegod63 mysql]# mysql -u root -h 192.168.1.63 -p123

[root@xuegod63 ~]# mysqladmin -u root password '123456' -p123

mysql> SET PASSWORD FOR 'grace1'@'localhost' = PASSWORD('123456');
#Note, your MySQL database already has a record: grace1'@'localhost
mysql> set password = password('1234567');
mysql> FLUSH PRIVILEGES;

[root@xuegod63 mysql]# /etc/init.d/mysqld stop
[root@xuegod63 mysql]# mysqld_safe --skip-grant-tables --skip-networking

[root@xuegod63 aa]# mysql #Execute mysql> update mysql.user set password=password('123456') where host='localhost' and user='root';
[root@xuegod63 aa]# /etc/init.d/mysqld restart
Stopping mysqld: [ OK ]