SQL Option 2: One Table Per Class, One Column Per Predicate

• Avoid such wide tables
• More natural SQL modelling
• Conceptual redundancy between human.name and doc.name
  • (no inheritance)

CREATE TABLE human (  # http://www.w3.org/2000/10/swap/test/demo1/biology#Human
  id INT PRIMARY KEY,
  name varchar(255),  # http://www.w3.org/2000/10/swap/test/demo1/friends-vocab#name
  pet INT             # http://www.w3.org/2000/10/swap/test/demo1/friends-vocab#pet
);
CREATE TABLE dog (  # http://www.w3.org/2000/10/swap/test/demo1/biology#Dog
  id INT PRIMARY KEY,
  name varchar(255)   # http://www.w3.org/2000/10/swap/test/demo1/friends-vocab#name
);
INSERT INTO human VALUES (6, 'Pat Smith', 7);
INSERT INTO dog   VALUES (7, 'Rover');

mysql> select * from human, dog where human.pet=dog.id;
+----+-----------+------+----+-------+
| id | name      | pet  | id | name  |
+----+-----------+------+----+-------+
|  6 | Pat Smith |    7 |  7 | Rover |
+----+-----------+------+----+-------+