Referential Integrity in SQL Primary and candidate keys and foreign keys can be specified as part of the sQL create table statement: The primary key clause lists attributes that comprise the primary key The unique key clause lists attributes that comprise a candidate key The foreign key clause lists the attributes that comprise the foreign key and the name of the relation referenced by the foreign key By default, a foreign key references the primary key attributes of the referenced table foreign key(account-number references account Short form for specifying a single column as foreign key account-number char(10) references account Reference columns in the referenced table can be explicitly specified but must be declared as primary/candidate keys foreign key(account-number references account(account-number Database System Concepts 6.8 OSilberschatz. Korth and SudarshanDatabase System Concepts 6.8 ©Silberschatz, Korth and Sudarshan Referential Integrity in SQL Primary and candidate keys and foreign keys can be specified as part of the SQL create table statement: The primary key clause lists attributes that comprise the primary key. The unique key clause lists attributes that comprise a candidate key. The foreign key clause lists the attributes that comprise the foreign key and the name of the relation referenced by the foreign key. By default, a foreign key references the primary key attributes of the referenced table foreign key (account-number) references account Short form for specifying a single column as foreign key account-number char (10) references account Reference columns in the referenced table can be explicitly specified but must be declared as primary/candidate keys foreign key (account-number) references account(account-number)