[MySQL] CASE - WHEN THEN ELSE - END

CASE 조건문

CASE WHEN 조건 THEN '반환 값' WHEN 조건 THEN '반환 값' ELSE 'WHEN 조건에 해당 안되는 경우 반환 값'  END

 

SELECT
    email,
    CONCAT(height, 'cm',', ',weight, 'kg') AS '키와 몸무게',
    weight / ((height/100) * (height/100)) AS BMI,
(CASE -- 사건, 경우
    WHEN weight IS NULL OR height IS NULL THEN '비만 여부 알 수 없음'
    WHEN weight / ((height/100) * (height/100)) >=25 THEN '과체중 또는 비만'
    WHEN weight / ((height/100) * (height/100)) >= 18.5 
        AND weight / ((height/100) * (height/100)) < 25
        THEN '정상'
    ELSE '저체중'
END) AS obesity_check
FROM copang_main.member
ORDER BY obesity_check ASC;