진료과별 총 예약 횟수 출력하기

https://school.programmers.co.kr/learn/courses/30/lessons/132202

• 문제 풀이

SELECT MCDP_CD AS "진료과코드", COUNT(*) AS "5월예약건수"
FROM APPOINTMENT
WHERE TO_CHAR(APNT_YMD, 'YYYY-MM') = '2022-05'
GROUP BY MCDP_CD
ORDER BY "5월예약건수", "진료과코드";

SELECT MCDP_CD AS "진료과코드", COUNT(*) AS "5월예약건수"
FROM APPOINTMENT
WHERE EXTRACT(YEAR FROM APNT_YMD) = 2022 AND EXTRACT(MONTH FROM APNT_YMD) = 5
GROUP BY MCDP_CD
ORDER BY COUNT(*), MCDP_CD;

• 실행 결과