错误代码：1054。“on 子句”中的未知列“s.Product_id”错误代码：1054。“on 子句”中的未知列“s.Product_id”

Question

我在 MySQL 中有错误：Error Code: 1054. Unknown column 's.Product_id' in 'on clause'

它出现在：

SELECT c.customer_ID, p.Product_id, p.Product_price, s.Items_quantity, (p.Product_price * s.Items_quantity) AS total FROM Products p LEFT JOIN Shopping_list s ON p.Product_id = s.Product_id LEFT JOIN Customer_sign_in c ON c.customer_ID = s.customer_ID LIMIT 0, 50000

有人知道为什么会这样吗？

Answer 1

你应该使用左连接

select c.customer_ID, p.Product_id, p.Product_price, s.Items_quantity,
    (p.Product_price * s.Items_quantity) as total from Products p LEFT JOIN Shopping_list s ON p.Product_id = s.Product_id LEFT JOIN Customer_sign_in c ON c.customer_ID = s.customer_ID;

Answer 2

你确定你有表Shopping_list 和一个名为Product_id 的列吗？

如果没有，请创建列并重试。

Answer 3

drop database if exists shopmeout;
create database shopmeout;
use shopmeout;
drop table if exists Customer_sign_in;

CREATE TABLE Customer_sign_in (
    customer_ID INT (50) not null,
    Name_customer varchar(255) not null,
    Credit_card BIGINT(100) not null,
    Password_cust TEXT(150) not null,
    Email_cust TEXT(50) not null,
    primary key (customer_ID)
);
insert into Customer_sign_in values( 19867889, 'Stefan Darescu', 9018783269173917, 'personalcomputer84', 'stefandarescu@gmail.com');
insert into Customer_sign_in values( 11958178, 'Mogens Hemming', 5090180120973782,'masadebiliard4', 'mogenshemming@yahoo.com');
insert into Customer_sign_in values( 52562523, 'Viggo Kristian', 9015908218093698,'asawece', 'viggokristian@gmail.com');
insert into Customer_sign_in values( 42515323, 'Asbjørn Hjalmar', 0198490128761903,'esrjgads', 'asbjornhjalmar@hotmail.com');
insert into Customer_sign_in values( 69723642, 'Rasmus Bjarne', 9180583647839793,'Sgsyhdfs', 'rasmusbjarne@outlook.com');

CREATE TABLE Products (
    Product_id INT(150) not null,
    Product_name VARCHAR(100) not null,
    Product_price DECIMAL(6,2) not null,
    Deduction_price INT(50) not null,
    Deadline DATE not null,
    PRIMARY KEY (Product_id)
);
insert into Products values( 509687, 'Plain Flower', 59.46, 10, '2013-05-30');
insert into Products values( 485901, 'Cow Milk', 17.85, 12, '2013-04-18');
insert into Products values( 908571, 'Kærgården', 131.75, 8, '2013-04-07');
insert into Products values( 432612, 'Chicken Eggs', 27.57, 9, '2013-03-31');
insert into Products values( 853235, 'Pepsi Cherry', 25.11, 12, '2013-03-25');
insert into Products values( 357342, 'Spaghetti', 10.8, 5, '2013-03-20');
insert into Products values( 123563, 'Spaghetti sos', 22.4, 10, '2013-03-17');

delimiter //
CREATE TRIGGER first_trigger BEFORE UPDATE ON Products
FOR EACH ROW
BEGIN
 IF NEW.Product_price < 20 THEN
 SET NEW.Product_price = 15;
 ELSEIF NEW.Product_price > 140 THEN
 SET NEW.Product_price = 80;
 END IF;
END;//
delimiter ;
UPDATE Products set Product_price = 25 where Product_id = 509687;
UPDATE Products set Product_price = 22 where Product_id = 908571;

CREATE TABLE Recipes (
    Recipes_id INT (10) not null,
    Recipe_name CHAR (150) not null,
    Recipe_descrip TEXT(255) not null,
    primary key (Recipes_id)
);
insert into Recipes values( 513678, 'Pancakes', 'Crack the eggs into a blender, add the flour, milk and a pinch of sea salt, and blitz until smooth.');
insert into Recipes values( 867523, 'Spaghetti Bolognese', 'Heat the oil in a large, heavy-based saucepan and fry the bacon until golden over a medium heat.');

CREATE TABLE Shopping_list (
    Shopping_list_id INT (50) not null,
    customer_ID INT (50) not null,
    Items_quantity INT (50) not null,
    primary key (Shopping_list_id),
    foreign key (customer_ID)
        REFERENCES
    Customer_sign_in (customer_ID)
);
insert into Shopping_list values( 14081869, 19867889, 15);
insert into Shopping_list values( 15163266, 11958178, 30);
insert into Shopping_list values( 34232325, 52562523, 3);
insert into Shopping_list values( 82412845, 42515323, 7);
insert into Shopping_list values( 36272236, 69723642, 5);

CREATE TABLE Payment (
    Payment_id INT(150) NOT NULL,
    customer_ID INT(150) NOT NULL,
    Date_pay DATETIME NOT NULL,
    Shopping_list_id INT(50) NOT NULL,
    PRIMARY KEY (Payment_id),
    FOREIGN KEY (customer_ID)
        REFERENCES Customer_sign_in (customer_ID),
    FOREIGN KEY (Shopping_list_id)
        REFERENCES Shopping_list (Shopping_list_id)
);
insert into Payment values( 84163801, 19867889, '2013-05-25 07:12:00', 14081869);
insert into Payment values( 89171750, 11958178, '2013-04-08 21:43:12', 15163266);
insert into Payment values( 19829247, 52562523, '2013-04-02 16:41:09', 34232325);
insert into Payment values( 35819204, 42515323, '2013-03-25 23:54:32', 82412845);
insert into Payment values( 25085739, 69723642, '2013-03-20 12:38:56', 36272236);

CREATE TABLE Has (
    Product_id INT(150) NOT NULL,
    Recipes_id INT(150) NOT NULL,
    FOREIGN KEY (Product_id)
        REFERENCES Products (Product_id),
    FOREIGN KEY (Recipes_id)
        REFERENCES Recipes (Recipes_id)
);
insert into Has values( 509687, 513678);
insert into Has values( 485901, 513678);
insert into Has values( 908571, 513678);
insert into Has values( 357342, 867523);
insert into Has values( 123563, 867523);

CREATE TABLE Goes (
    Product_id INT(150) NOT NULL,
    Shopping_list_id INT(150) NOT NULL,
    FOREIGN KEY (Product_id)
        REFERENCES Products (Product_id),
    FOREIGN KEY (Shopping_list_id)
        REFERENCES Shopping_list (Shopping_list_id)
);
insert into Goes values( 485901, 14081869);
insert into Goes values( 123563, 14081869);
insert into Goes values( 908571, 14081869);
insert into Goes values( 485901, 82412845);
insert into Goes values( 123563, 34232325);
insert into Goes values( 357342, 34232325);

select * from Shopping_list;
select * from Payment;
select * from Customer_sign_in;
select * from Recipes;
select * from Products;
select * from Has;
select * from Goes;

SELECT c.customer_ID, p.Product_id, p.Product_price, s.Items_quantity,
(p.Product_price * s.Items_quantity) AS total FROM Products p LEFT JOIN Shopping_list s ON p.Product_id = s.Product_id LEFT JOIN Customer_sign_in c ON c.customer_ID = s.customer_ID;