-- NTILE 풀이 --
SELECT T.ID,
CASE
WHEN NT = 1 THEN 'CRITICAL'
WHEN NT = 2 THEN 'HIGH'
WHEN NT = 3 THEN 'MEDIUM'
WHEN NT = 4 THEN 'LOW'
END AS COLONYNAME
FROM
(SELECT ID,NTILE(4) OVER(ORDER BY SIZEOFCOLONY DESC) AS NT
FROM ECOLIDATA) AS T
ORDER BY ID;

--PERCENTRANK 풀이 --
SELECT T.ID,
CASE
WHEN PR>0.75 THEN 'LOW'
WHEN 0.75>=PR AND PR>0.5 THEN 'MEDIUM'
WHEN 0.5>=PR AND PR>0.25 THEN 'HIGH'
WHEN 0.25>=PR THEN 'CRITICAL'
END AS COLONYNAME
FROM
(SELECT ID,PERCENTRANK() OVER (ORDER BY SIZEOFCOLONY DESC) AS PR
FROM ECOLIDATA) AS T
ORDER BY T.ID;