Question

当我尝试在SQLFiddle中运行这段代码时，我收到此错误。它使用MySQL 5.6。

无法添加或更新子行：外键约束失败（db_9_f9acae。order_items，CONSTRAINT order_items_ibfk_1 FOREIGN KEY（Donut_Order_ID）参考custorder （Donut_Order_ID））

我的代码如下所示：

CREATE TABLE Customer (
  Customer_ID INTEGER PRIMARY KEY AUTO_INCREMENT,
  CustFirstName VARCHAR(50) NOT NULL,
  CustLastName VARCHAR(50) NOT NULL,
  Address VARCHAR(50) NOT NULL,
  AptNum VARCHAR(50),
  City VARCHAR(50) NOT NULL,
  State VARCHAR(13) NOT NULL,
  Zip VARCHAR(15) NOT NULL,
  HomePhn VARCHAR(20),
  MobPhn VARCHAR(20),
  OthPhn VARCHAR(20) 
);

CREATE TABLE Donut (
  Donut_ID INTEGER PRIMARY KEY,
  Donut_Name VARCHAR(255) NOT NULL,
  Donut_Description VARCHAR(255) NOT NULL,
  Donut_Price FLOAT NOT NULL
);

CREATE TABLE CustOrder (
  Donut_Order_ID INTEGER PRIMARY KEY,
  Date DATE NOT NULL,
  Notes VARCHAR(255) NOT NULL,
  Customer_ID INTEGER,
  FOREIGN KEY (Customer_ID) REFERENCES Customer (Customer_ID)
);

CREATE TABLE Order_Items (
  Donut_Order_ID INTEGER NOT NULL,
  Donut_ID INTEGER NOT NULL,
  Qty INTEGER NOT NULL,
  PRIMARY KEY (Donut_Order_ID, Donut_ID),
  FOREIGN KEY (Donut_Order_ID) REFERENCES CustOrder (Donut_Order_ID),
  FOREIGN KEY (Donut_ID) REFERENCES Donut (Donut_ID)
);

CREATE VIEW CustInfo AS 
SELECT CONCAT(CustFirstName,' ', CustLastName) AS CustFullName,
 Customer_ID,
 Address,
 AptNum,
 City,
 State,
 Zip,
 HomePhn,
 MobPhn,
 OthPhn
 FROM Customer;

CREATE INDEX DonutIndex ON Donut (Donut_Name);

INSERT INTO Customer VALUES 
(1, "John", "Glenn", 1, NULL, "Kennedy Space Center", "FL", "32899", "(321) 867-5000", NULL, NULL), 
(2, "Theodore", "Von Karman", "4800 Oak Dr", "Jet Propulsion Laboratory", "Pasadena", "CA", "91109", "(818) 354-4321", NULL, NULL),
(3, "Margaret", "Hamilton", "555 Technology Square", "Charles Stark Draper Laboratory", "Cambridge", "MA", "02139", "(617) 258-1000", "(123)456-7890", NULL);

INSERT INTO Donut
VALUES
(1, 'Plain' , 'Plain Donut' , 1.50),
(2, 'Glazed' , 'Glazed Donut' , 1.75),
(3, 'Cinnamon' , 'Cinnamon Donut' , 1.75),
(4, 'Chocolate' , 'Chocolate Donut' , 1.75),
(5, 'Sprinkle' , 'Sprinkle Donut' , 1.75),
(6, 'Gluten-Free' , 'Gluten-Free Donut' , 2.00);


INSERT INTO Order_Items VALUES
(2 , 4 , 3),
(3, 2, 1);

INSERT INTO CustOrder VALUES
('1', '11-24-2017', NULL, '1'),
('2', '11-25-2017', NULL, '2');

这是我第一次使用与SQL相关的任何内容并试图参考MySQL文档，但我不知道我做错了什么。在添加底部2 INSERT INTO语句之后才会出现错误。任何帮助将不胜感激。

Answer 1

您收到此错误是因为您尝试在引用表中缺少引用的表中插入数据集，例如在Order_Items中您试图将custorder表与Donut_Order_ID链接起来2和3，但它是空的

首先填写您的custorder，然后与您的表格相关联

INSERT INTO CustOrder VALUES
('1', '11-24-2017', NULL, '1'),
('2', '11-25-2017', NULL, '2');

INSERT INTO Order_Items VALUES
(2 , 4 , 3),
(3, 2, 1);

此外，我发现CustOrder对Donut_Order_ID = 3没有参考，但在Order_Items数据中，您尝试与此缺失参考链接，这将再次给您错误

demo

MySQL 5.6外键错误消息

1 个答案: