[SQL | 프로그래머스 | Lv_2] 부모의 형질을 모두 가지는 대장균 찾기

SELECT
    A.ID, A.GENOTYPE, B.GENOTYPE AS PARENT_GENOTYPE
FROM
    ECOLI_DATA A
LEFT JOIN
    ECOLI_DATA B ON A.PARENT_ID = B.ID
WHERE
    A.GENOTYPE & B.GENOTYPE = B.GENOTYPE
ORDER BY A.ID

# 데이터 확인용
# SELECT
#     A.ID,
#     CONV(A.GENOTYPE, 10, 2) AS 'GENOTYPE',
#     CONV(B.GENOTYPE, 10, 2) AS 'PARENT_GENOTYPE',
#     CONV(A.GENOTYPE & B.GENOTYPE, 10, 2) AS '일치하는 부분'
# FROM
#     ECOLI_DATA A
# LEFT JOIN
#     ECOLI_DATA B ON A.PARENT_ID = B.ID

✔ 링크 : https://school.programmers.co.kr/learn/courses/30/lessons/301647