Write a query identifying the type of each record in the TRIANGLES table using its three side lengths. Output one of the following statements for each record in the table:
- Equilateral: It’s a triangle with sides of equal length.
- Isosceles: It’s a triangle with sides of equal length.
- Scalene: It’s a triangle with sides of differing lengths.
- Not A Triangle: The given values of A, B, and C don’t form a triangle.
Input Format
The TRIANGLES table is described as follows:
Each row in the table denotes the lengths of each of a triangle’s three sides.
Sample Input
Sample Output
Isosceles
Equilateral
Scalene
Not A Triangle
Explanation
Values in the tuple (20,20,23) form an Isosceles triangle, because A=B.
Values in the tuple (20,20,20) form an Equilateral triangle, because A=B=C. Values in the tuple (20,21,22) form a Scalene triangle, because A!=B!=C.
Values in the tuple (13,14,30) cannot form a triangle because the combined value of sides A and B is not larger than that of side C.
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 B = C OR A = C THEN ‘Isosceles’
ELSE ‘Scalene’
END
FROM TRIANGLES;