In SQL Server , I got this error -> "There are no primary or candidate keys in the referenced table 'BookTitle' that match the referencing column list in the foreign key 'FK_ BookCopy _Title__2F10007B'." I first created a relation called the BookTitle relation. CREATE TABLE BookTitle ( ISBN CHAR(17) NOT NULL, Title VARCHAR(100) NOT NULL, Author_Name VARCHAR(30) NOT NULL, Publisher VARCHAR(30) NOT NULL, Genre VARCHAR(20) NOT NULL, Language CHAR(3) NOT NULL, PRIMARY KEY (ISBN, Title)) Then I created a relation called the BookCopy relation. This relation needs to reference to the BookTitle