Untitled

SELECT
  CASE 
    WHEN A + B <= C or A + C <= B or B + C <= A THEN 'Not A Triangle'
    WHEN A = B and B = C THEN 'Equilateral'
    WHEN A = B or A = C or B = C THEN 'Isosceles'
    WHEN A <> B and B <> C THEN 'Scalene'
  END tuple
FROM TRIANGLES;