binaryTree.txt

SELECT N, 
/* Gets the node number*/

IF(P IS NULL, 'Root', 
/* Check to see if the parent node is NULL. If so, then it's the root (as it has no parent.) */
 IF((SELECT COUNT(*) FROM BST WHERE P = B.N)>0, 'Inner', 'Leaf')) 
/* Check to see if a parent node exists, or if the COUNT from the table where parent nodes equal the node number, then it must be an inner node. Otherwise it's a leaf. */ 
 FROM BST AS B
ORDER BY N;