WITH date_diff AS ( SELECT TO_DATE('20250101 132344', 'YYYYMMDD HH24MISS') AS created_date, SYSDATE AS current_date FROM dual)SELECT CASE WHEN current_date - created_date >= 1 THEN TRUNC(current_date - created_date) || ' days' WHEN (current_date - created_date) * 24 >= 1 THEN TRUNC((current_date - created_date) * 24) || ' hours' ..

nanoseconds가 필요하면 SYSTIMESTAMP를 사용해야 함

'2025-01-16T07:14:47Z'를 날짜로 변환하기SELECT TO_DATE('2025-01-16T07:14:47Z', 'YYYY-MM-DD"T"HH24:MI:SS"Z"') FROM DUAL;SELECT TO_CHAR(SYSDATE, 'YYYY-MM-DD"T"HH24:MI:SS"Z"') FROM DUAL;

SELECT ROUND(10000000/1234, 1) AS resultFROM DUAL;

2개의 인수SELECT NVL(column1, 'default') AS resultFROM table_name;3개 이상 인수SELECT COALESCE(column1, column2, 'default') AS resultFROM table_name;