[Lv.2] 진료과별 총 예약 횟수 출력하기[EXTRACT]

 

진료과별 총 예약 횟수 출력하

문제 해결을 위한 개념 정리

 

✅ EXTRACT

: 날짜에서 년, 월, 일, 시간 등을 추출

 

→ EXTRACT (unit FROM date)

date : "2022-04-14 09:30:12.345678"

unit	출력 예시	출력 단위
MICROSECOND	345678	MICROSECONDS
SECOND	12	SECONDS
MINUTE	30	MINUTES
HOUR	9	HOURS
DAY	14	DAYS
WEEK	15	WEEKS
MONTH	4	MONTHS
QUARTER	2	QUARTERS
YEAR	2022	YEARS
SECOND_MICROSECOND	12345678	'SECONDS.MICROSECONDS'
MINUTE_MICROSECOND	3012345678	'MINUTES:SECONDS.MICROSECONDS'
MINUTE_SECOND	3012	'MINUTES:SECONDS'
HOUR_MICROSECOND	93012345678	'HOURS:MINUTES:SECONDS.MICROSECONDS'
HOUR_SECOND	93012	'HOURS:MINUTES:SECONDS'
HOUR_MINUTE	930	'HOURS:MINUTES'
DAY_MICROSECOND	14093012345678	'DAYS HOURS:MINUTES:SECONDS.MICROSECONDS'
DAY_SECOND	14093012	'DAYS HOURS:MINUTES:SECONDS'
DAY_MINUTE	140930	'DAYS HOURS:MINUTES'
DAY_HOUR	1409	'DAYS HOURS'
YEAR_MONTH	202204	'YEARS-MONTHS'

 

 

문제 해결 코드

SELECT MCDP_CD AS `진료과코드`, COUNT(PT_NO) AS `5월예약건수`
FROM APPOINTMENT
WHERE EXTRACT(YEAR_MONTH FROM APNT_YMD)='202205'
GROUP BY MCDP_CD
ORDER BY `5월예약건수` ASC, `진료과코드` ASC;