leetcode-sql/medium/608. Tree Node.sql at main · cM2908/leetcode-sql · GitHub

Name: leetcode-sql/medium/608. Tree Node.sql at main · cM2908/leetcode-sql · GitHub
Rating: 4.8 (1311 reviews)
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SELECT DISTINCTt1.id,
 CASE WHEN t1.p_id IS NULL THEN 'Root'
 WHEN t2.id IS NULL THEN 'Leaf'
 ELSE 'Inner' END AS Type
FROM tree_608 t1
LEFT JOIN tree_608 t2 ONt1.id=t2.p_id
ORDER BYt1.id;