SELECT CASE WHEN (A+B<=C OR B+C<=A OR C+A<=B) THEN 'Not A Triangle' WHEN (A=B AND B=C AND C=A)THEN 'Equilateral' WHEN (A=B OR B=C OR C=A)THEN 'Isosceles' ELSE 'Scalene' END AS TRIANGLE_TYPE FROM TRIANGLES;

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 AS Triangle_Type FROM TRIANGLES;

select case when A+B<=C OR B+C<=A OR A+C<=B 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

and the arrangement is must of the conditions

SELECT KIND from (SELECT A,B,C, CASE WHEN A+B<=C OR B+C<=A OR A+C<=B THEN 'Not A Triangle' WHEN A=B AND B=C AND A=C THEN 'Equilateral' WHEN A=B OR B=C OR A=C THEN 'Isosceles' ELSE 'Scalene' END AS "KIND" FROM TRIANGLES) A

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 and b!=c or c=a and c!=b or b=c and b!=a then 'Isosceles' when a!=b and b!=c and c!=a then 'Scalene' end else 'Not A Triangle' end from triangles