可以用一句语句实现：GRANT ALL ON *.* TO 用户名@"%" IDENTIFIED BY "密码"

然后需要刷一下：flush privileges

insert into mysql.user(host,user,password) values ("localhost","hbchen",p
assword("hbchen"));
这样就创建了一个名为：hbchen 密码为：hbchen (的)用户。?
然后登录一下。?
mysql>exit;?
@>mysql -u?hbchen -p?
@>输入密码?
mysql>登录成功?
2.为用户授权。?
//登录MYSQL（有ROOT权限）。我们里我们以ROOT身份登录.?
@>mysql -u root -p?
@>密码?
//首先为用户创建一个数据库(phplampDB)?
mysql>create database phplampDB;?
//授权phplamp用户拥有phplamp数据库(的)所有权限。?
>grant all privileges on phplampDB.* to?hbchen@localhost?identified by 'hbchen';?
//刷新系统权限表?
mysql>flush privileges;?
mysql>其它们操作?
/*?
如果想指定部分权限给一用户，可以这样来写:?
mysql>grant select,update on phplampDB.* to?hbchen@localhost?identified by 'hbchen';?
//刷新系统权限表。?
mysql>flush privileges;?
*/?
3.删除用户。?
@>mysql -u root -p?
@>密码?
mysql>Delete FROM user Where User="hbchen" and Host="localhost";?
mysql>flush privileges;?
//删除用户(的)数据库?
mysql>drop database phplampDB;?
4.修改指定用户密码。?
@>mysql -u root -p?
@>密码?
mysql>update mysql.user set password=password('新密码') where User="hbchen" and Host="localhost";?
mysql>flush privileges;?
5.列出所有数据库?
mysql>show database;?
6.切换数据库?
mysql>use '数据库名';?
7.列出所有表?
mysql>show tables;?
8.显示数据表结构?
mysql>describe 表名;?
9.删除数据库和数据表?
mysql>drop database 数据库名;?
mysql>drop table 数据表名;

?例如：--新建用户
insert into mysql.user(host,user,password) values ("localhost","hbchen",p
assword("hbchen"));
---授予权限
grant all privileges on mysql.* to?hbchen@localhost?identified by 'hbchen';
--授予部分权限
?grant select,update on mysql.* to?hbhcen@localhost?identified by 'hbchen';

--更改密码?
update mysql.user set password='123456'where User='hbchen';

use mysql；??
update user set password=password('hahaha') where user='hbchen';
-