时间:2021-07-01 10:21:17 帮助过:25人阅读
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!