Re: CANNOT ADD FOREIGN KEY CONSTRAIN

[Phillip Ward]

The Data Types used in Foreign Key relationships must be the same in both Tables:

CREATE TABLE Coffeeshop 
( Shop_id INT UNSIGNED NOT NULL 
, . . . 
, PRIMARY KEY (Shop_id) 
);

CREATE TABLE employee 
( . . . 
, Employee_Shop_Id INT
, . . . 
);

ALTER TABLE Employee 
. . . 
ADD CONSTRAINT checks 
FOREIGN KEY (Employee_Shop_Id) REFERENCES Coffeeshop (Shop_Id)

Regards, Phill W.