mysql sql statement summary

create database mytest default charset=utf8 // create the database
create table users // create tables
(
user_id int not null auto_increment,
user_name varchar(20) not null,
description varchar(200),
primary key PK_userid(user_id)
);
show create table users; // view the sql statement that created the table
desc users; // view the table structure
alter table users add(user_age int not null); // add table fields
insert into users(user_name,description,user_age) values('chen','this is good men.',28); // insert 1 piece of data
// query the database
select * from users limit 5; // query the first 5 items
SELECT * FROM users LIMIT 6,2; // starting from # 6, check # 2