day3_12

vo:view object 就是用在界面显示的对象
po:persistent object 数据库持久对象，刚才数据库查询出来的对象就是po
dto:data transfer object 数据传输对象，一般用在代码中对数据进行处理

八表查询

sql语句

create table orders(oid varchar(32) primary key, uid int,price double, payid int references pays(payid) , aid int);
create table details(did varchar(32) primary key, count int, pid varchar(32), oid varchar(32));
create table products(pid varchar(32) primary key, name varchar(20), imgid int, price double, tid varchar(32) references types(tid));
create table types(tid varchar(32) primary key, name varchar(20) not null unique);
create table users(uid int primary key auto_increment, name varchar(20) not null unique, pass varchar(20) not null, phone varchar(11));
create table pays(payid int,payType varchar(32),state varchar(20));
create table imgs(imgid int,background varchar(20),leixing varchar(20));
create table addrs(aid int,province varchar(10),city varchar(10));

insert into users values(1,‘zhangsan’,‘123456’,‘1782911’);
insert into orders values(‘1’,1,19999,1,1);
insert into addrs values(1,‘shanxi’,‘xian’);
insert into pays values(1,true);
insert into details values(‘1’,3,‘1’,‘1’);
insert into products values(‘1’,‘java’,1,9999,‘1’);
insert into imgs values(1,‘black’,‘png’);
insert into types values(‘1’,‘book’);