Home > Database > Mysql Tutorial > mysql left join 如何使用

mysql left join 如何使用

WBOYWBOYWBOYWBOYWBOYWBOYWBOYWBOYWBOYWBOYWBOYWBOYWB
Release: 2016-06-06 09:33:57
Original
1145 people have browsed it

mysql

有三张表:products、orders、order_product

create table products(
product_code varchar(20) primary key not null,
product_name varchar(20),
product_price float
);

create table orders(
order_id varchar(40) primary key not null,
order_status enum('0','1','2') default '0',
);

create table order_product(
order_id varchar(40) primary key not null,
product_code varchar(20)
foreign key(order_id) references orders(order_id),
foreign key(product_code) references products(product_code)
);

问题1:查询 order_product 表(只要有一条记录就行),要求 order_product.product_code='1111111' 并且 order_product.order_id 在 orders 表里已存在,并且 orders.order_status='0'?

我的写法:SELECT * FROM orders_product AS op LEFT JOIN orders AS od ON op.product_id=od.product_id WHERE op.product_code='1111'AND od.order_status='0' LIMIT 1;

结果报 1045 错误,请高手指点,非常感谢!

Related labels:
Statement of this Website
The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn
Latest Issues
MySQL stops process
From 1970-01-01 08:00:00
0
0
0
Error when installing mysql on linux
From 1970-01-01 08:00:00
0
0
0
phpstudy cannot start mysql?
From 1970-01-01 08:00:00
0
0
0
Popular Tutorials
More>
Latest Downloads
More>
Web Effects
Website Source Code
Website Materials
Front End Template