오라클 날짜 연산, 출력 포멧

1. 현재 날짜 조회하기

select sysdate
from dual;

2. 날자 포멧 변경하기

alter session set nls_date_format='YYY-MM-DD HH24:MI:SS';

3. 날짜 함수 (Using Date Functions)

Function	Result
MONTHS_BETWWN('01-SEP-95','11-JAN-94')	19.6774194
ADD_MONTHS('11-JAN-94',6)	'11-JUL-94
NEXT_DAY('01-SEP-95','FRIDAY')	'08-SEP-95'
LAST_DAY('01-FEB-95')	'28-FEB-95'

Assume SYSDATE ='25-JUL-03':

Function	Result
ROUND(SYSDATE,'MONTH')	01-AUG-03
ROUND(SYSDATE,'YEAR')	01-JAN-04
TRUNC(SYSDATE,'MONTH')	01-JUL-03
TRUNC(SYSDATE,'YEAR')	01-JAN-03

4. 날짜 포멧 모델 요소 (Elements of the Date Format Model)

Function	Result
HH24:MI:SS AM	15:45:32 PM
DD "of" MONTH	12 of OCTOBER
ddspth	fourteenth
FMDD MONTH YYYY	17 June 1987

출처 : 오라클 공인 교재 SQL Fundamentals 3-20~