三表联合查询

use bishe_jxc;

#用户和购票表为主表，购票细节表为子表

#创建用户表
create table user_jxc(
uId_jxc int not null auto_increment,
uName_jxc varchar(16)  not null,
uPwd_jxc varchar(16) not null,
uSex_jxc varchar(4) not null,
uTelp_jxc varchar(11) not null,
primary key(uId_jxc)
)engine=InnoDB auto_increment =1;

#创建购票表
create  table order_jxc(
orderId_jxc int not null auto_increment,
tickDate_jxc varchar(50) not null,
fabuer varchar(10) not null,
primary key(orderId_jxc)
)engine=InnoDB auto_increment =10;

#创建订单细节表a
create table orderdetail_jxc(
orderDetailId_jxc int not null auto_increment,
orderId_jxc int null,
uId_jxc int not null,
orderNum_jxc int null,
primary key(orderDetailId_jxc) 
)engine=InnoDB auto_increment =1;


#设置用户和订单细节表的外键alter
alter table orderdetail_jxc
add constraint FK_orderdetail_jxc_user_jxc_uId_jxc
foreign key(uId_jxc) references user_jxc(uId_jxc);

#设置订单表和订单细节表的外键alter
alter table orderdetail_jxc
add constraint FK_orderdetail_jxc_order_jxc_orderId_jxc
foreign key(orderId_jxc) references order_jxc(orderId_jxc);


#--------------------------------------------------------------------------

#添加用户
insert into user_jxc values(null,'蒋星灿','1234','男','15574784980');

#添加订单
insert into order_jxc value (null,'2020.11.30','蒋星灿');

#添加购票细节表
insert into orderdetail_jxc value (null,10,1,2);

#三表连接查询alter
select 
u.orderDetailId_jxc,u.orderNum_jxc,c.tickDate_jxc,s.uName_jxc
from orderdetail_jxc u
left Join order_jxc c On  c.orderId_jxc = u.orderId_jxc
left join user_jxc s On s.uId_jxc = u.uId_jxc;

 #通过商品ID 查询这个商品的评论
select 
u.*,c.*,s.*
from remark_jxc u
left join goods_jxc c on c.goodId_jxc = u.goodId_jxc
left join user_jxc s on s.uId_jxc = u.uId_jxc
where c.goodId_jxc =23;

查询订单细节ID,订单数量，门票时间，用户名