Type of Triangle in MYSQL

Question

Problem statement:

Write a query identifying the type of each record in the TRIANGLES table using its three side lengths. Output one of the followin

Answer 1

Your answer is actually right. But the one little information (Triangle's 'Right' Definition) is missing on the question (which is not your fault) that if two sides' sum is bigger OR EQUAL to another side then it's not a triangle

The only thing you should do is putting '=' near of your '<'

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 as triangles_type 
from TRIANGLES; 

Answer 2

MySQL With All Test Case Passed:-

SELECT CASE 
WHEN A + B > C AND A+C>B AND B+C>A THEN CASE 
WHEN A = B AND B = C THEN 'Equilateral' 
WHEN A = B OR B = C OR A = C THEN 'Isosceles' 
WHEN A != B OR B != C OR A != C THEN 'Scalene' 
END ELSE 'Not A Triangle' END FROM TRIANGLES;

Answer 3

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;

1. By using case statement check if given input is a triangle or not.
2. If it is a triangle then check if all sides are same if true the triangle type is 'Equilateral'.
3. If not then check if any two sides are equal if true the triangle type is 'Isosceles'
4. In the case of not equal, any sides the triangle type is 'Scalene'. We can directly use ELSE also.

Answer 4

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"
else "Scalene"
end as triangles_type
from TRIANGLES;

Answer 5

select 
case
    when (a+b>c) and (b+c>a) and (c+a>b) then
        case
            when a=b and b=c then 'Equilateral'
            when a=b or b=c or c=a then 'Isosceles'
            else 'Scalene'
        end
    else 'Not A Triangle'
end 
from triangles;

Answer 6

For Oracle 11g this is working:

SELECT CASE WHEN A+B>C then case when A=B AND B=C THEN 'Equilateral'
   WHEN A=B OR B=C OR A=C THEN 'Isosceles'
   WHEN A!=B or B!=C OR A!=C THEN 'Scalene' END
   ELSE 'Not A Triangle' END
   FROM TRIANGLES;