LAST_DAY 함수는 인자로 지정된 DATE 값에서 해당 월의 마지막 날짜 값을 DATE 타입으로 반환한다.
LAST_DAY ( date_argument )
date_argument :
• date
• NULL
--it returns last day of the momth in DATE type
SELECT LAST_DAY(DATE '1980-02-01'), LAST_DAY(DATE '2010-02-01');
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02/28/1980 02/28/2010
--it returns last day of the momth when explicitly casted to DATE type
SELECT LAST_DAY(CAST (SYS_TIMESTAMP AS DATE)), LAST_DAY(CAST (SYS_DATETIME AS DATE));
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02/28/2010 02/28/2010