INSERT INTO T(DATE_COLUMN) VALUES('01/02/03'); -- 기본 날짜 형식이 바뀐다면 ??
INSERT INTO T(DATE_COLUMN) VALUES(TO_DATE('01/02/03','DD/MM/YY')); -- 03이 1903인지 2003 불확실
INSERT INTO T(DATE_COLUMN) VALUES(TO_DATE('01/02/03','DD/MM/YYYY')); -- 정상
SQL> CREATE TABLE T (X DATE);
테이블이 생성되었습니다.
SQL>
SQL> INSERT INTO T (X) VALUES (TO_DATE('25-06-2005 12:01:00', 'DD-MM-YYYY HH24:M
I:SS'));
1 개의 행이 만들어졌습니다.
SQL>
SQL> SELECT X, DUMP(X, 10) D FROM T;
X D
-------- --------------------
05/06/25 Typ=12 Len=7: 120,105,6,25,13,2,1
-- 세기,연도 바이트(DUMP 결과는 120.105)는 100을 추가하여 저장
-- 세기와 연도의 정확한 값을 보려면 100을 빼야한다. 100을 추가하여 표현하는 이유는 B.C(기원전)와 A.D(기원후)를 지원하기위함
-- 세기 바이트에서 100을 뺀 결과가 음수면 B.C를 의미한다
SQL> CREATE TABLE T (X DATE);
테이블이 생성되었습니다.
SQL> ALTER SESSION SET NLS_TERRITORY='AMERICA';
세션이 변경되었습니다.
SQL>
SQL> ALTER SESSION SET NLS_LANGUAGE='AMERICAN';
Session altered.
SQL>
SQL> ALTER SESSION SET NLS_DATE_LANGUAGE='AMERICAN';
Session altered.
SQL>
SQL> INSERT INTO T (X) VALUES (TO_DATE('25-JUN-2005 12:01:00', 'DD-MON-YYYY HH24
:MI:SS'));
1 row created.
SQL> SELECT X, DUMP(X, 10) D FROM T;
X D
------------ -----------------------------------
25-JUN-05 Typ=12 Len=7: 120,105,6,25,13,2,1
SQL> INSERT INTO T (X) VALUES (TO_DATE('01-JAN-4712BC', 'DD-MON-YYYYBC HH24:MI:SS'));
1 row created.
SQL> INSERT INTO T (X) VALUES (TO_DATE('01-JAN-4710BC', 'DD-MON-YYYYBC HH24:MI:SS'));
1 row created.
SQL> SELECT X, DUMP(X, 10) D FROM T;
X D
------------ --------------------------------------------------
25-JUN-05 Typ=12 Len=7: 120,105,6,25,13,2,1
01-JAN-12 Typ=12 Len=7: 53,88,1,1,1,1,1
01-JAN-10 Typ=12 Len=7: 53,90,1,1,1,1,1
SQL> CREATE TABLE T(WHAT VARCHAR2(10), X DATE);
Table created.
SQL> INSERT INTO T (WHAT,X) VALUES('ORIG', TO_DATE('25-JUN-2005 12:01:00','DD-MN-YYYY HH24:MI:SS'));
1 row created.
SQL> INSERT INTO T (WHAT, X)
2 SELECT 'MINUTE', TRUNC(X,'MI') FROM T
3 UNION ALL
4 SELECT 'DAY', TRUNC(X,'DD') FROM T
5 UNION ALL
6 SELECT 'MONTH', TRUNC(X,'MM') FROM T
7 UNION ALL
8 SELECT 'YEAR', TRUNC(X,'Y') FROM T;
4 rows created.
SQL> SELECT WHAT, X, DUMP(X,10) D FROM T;
WHAT X D
--------- --------- ------------------------------
ORIG 25-JUN-05 Typ=12 Len=7: 120,105,6,25,13,2,1
MINUTE 25-JUN-05 Typ=12 Len=7: 120,105,6,25,13,2,1
DAY 25-JUN-05 Typ=12 Len=7: 120,105,6,25,1,1,1
MONTH 01-JUN-05 Typ=12 Len=7: 120,105,6,1,1,1,1
YEAR 01-JAN-05 Typ=12 Len=7: 120,105,1,1,1,1,1
-- 시분초 필드는 실제 값에서 각가 1을 뺀 1의 자리에 저장
-- 밥 12시는 일자 필드에 1,1,1로 표시
-- 7바이트 포맷은 자연적으로 정렬
시간단위 | 연산 | 설명 |
---|---|---|
N초 | DATE + n/24/60/60 DATE + n/86400 DATE + NUMTODSINTERVAL(n,'second') | 하루(86,000초) = 24시*60분*60초 |
N분 | DATE + n/24/60 DATE + n/1440 DATE + NUMTODSINTERVAL(n,'minute') | 하루(1,440분) = 24시*60분 |
N시간 | DATE + n/24 DATE + NUMTODSINTERVAL(n,'hour') | 하루(24시간) = 24시 |
N일 | DATE + n | 하루(24시간) = DATE + N |
N주 | DATE + 7*n | 1주 = 7일 |
N월 | ADD_MONTHS(DATE,n) DATE+NUMTOYMINERVAL(n,'month') | ADD_MONTHS 내장함수 사용, DATE에 N개월 인터벌 |
N년 | ADD_MONTHS(DATE,12*n) DATE+NUMTOYMINTERVAL(n,'year') | ADD_MONTHS 내장함수에 12*n 사용 |
-- 마지막일자가 31일 이하인 달에 1개월을 더하면 어떤지 확인
SQL> ALTER SESSION SET NLS_DATE_FORMAT = 'DD-MON-YYYY HH24:MI:SS';
Session altered.
SQL> SELECT DT, ADD_MONTHS(DT,1)
2 FROM (SELECT TO_DATE('29-FEB-2000','DD-MON-YYYY') DT FROM DUAL);
DT ADD_MONTHS(DT,1)
----------------------- -----------------------
29-FEB-2000 00:00:00 31-MAR-2000 00:00:00
SQL>
SQL> SELECT DT, ADD_MONTHS(DT,1)
2 FROM (SELECT TO_DATE('28-FEB-2001','DD-MON-YYYY') DT FROM DUAL);
DT ADD_MONTHS(DT,1)
----------------------- -----------------------
28-FEB-2001 00:00:00 31-MAR-2001 00:00:00
SQL>
SQL> SELECT DT, ADD_MONTHS(DT,1)
2 FROM (SELECT TO_DATE('30-JAN-2001','DD-MON-YYYY') DT FROM DUAL);
DT ADD_MONTHS(DT,1)
----------------------- -----------------------
30-JAN-2001 00:00:00 28-FEB-2001 00:00:00
SQL>
SQL> SELECT DT, ADD_MONTHS(DT,1)
2 FROM (SELECT TO_DATE('30-JAN-2000','DD-MON-YYYY') DT FROM DUAL);
DT ADD_MONTHS(DT,1)
----------------------- -----------------------
30-JAN-2000 00:00:00 29-FEB-2000 00:00:00
-- 틀린 ...다른결과값을 보여준다
SQL> SELECT DT, DT+NUMTOYMINTERVAL(1,'month')
2 FROM (SELECT TO_DATE('29-FEB-2000','DD-MON-YYYY') DT FROM DUAL);
DT DT+NUMTOYMINTERVAL(1,'M'
----------------------- -----------------------
29-FEB-2000 00:00:00 29-MAR-2000 00:00:00
SQL>
SQL> SELECT DT, DT+NUMTOYMINTERVAL(1,'month')
2 FROM (SELECT TO_DATE('28-FEB-2001','DD-MON-YYYY') DT FROM DUAL);
DT DT+NUMTOYMINTERVAL(1,'M'
----------------------- -----------------------
28-FEB-2001 00:00:00 28-MAR-2001 00:00:00
-- 에러발생(2001.02.30 은 없음)
SQL> SELECT DT, DT+NUMTOYMINTERVAL(1,'month')
2 FROM (SELECT TO_DATE('30-JAN-2001','DD-MON-YYYY') DT FROM DUAL);
SELECT DT, DT+NUMTOYMINTERVAL(1,'month')
*
ERROR at line 1:
ORA-01839: date not valid for month specified
-- 에러발생(2000.02.30 은 없음)
SQL> SELECT DT, DT+NUMTOYMINTERVAL(1,'month')
2 FROM (SELECT TO_DATE('30-JAN-2000','DD-MON-YYYY') DT FROM DUAL);
SELECT DT, DT+NUMTOYMINTERVAL(1,'month')
*
ERROR at line 1:
ORA-01839: date not valid for month specified
-- 사용하기 좋은 예는 아니지만 모두 맞는 값이다.
SQL> SELECT DT2-DT1
2 , MONTHS_BETWEEN(DT2, DT1) MONTHS_BTWN
3 , NUMTODSINTERVAL (DT2-DT1,'day') DAYS
4 , NUMTOYMINTERVAL (TRUNC(MONTHS_BETWEEN(DT2,DT1)),'month') MONTHS
5 FROM ( SELECT TO_DATE('29-FEB-2000 01:02:03', 'DD-MON-YYYY HH24:MI:SS') DT1,
6 TO_DATE('15-MAR-2001 11:22:33', 'DD-MON-YYYY HH24:MI:SS') DT2
7 FROM DUAL);
DT2-DT1 MONTHS_BTWN DAYS MONTHS
----------- ------------- ----------------------------- -------------------------
380.430903 12.5622872 +000000380 10:20:30.000000000 +000000001-00
-- 두 DATE사이의 차이가 1년 15일 10시간 20분 30초라는 걸 확인
SQL> SELECT NUMTOYMINTERVAL(TRUNC(MONTHS_BETWEEN(DT2, DT1)), 'MONTH') YEARS_MONTHS
2 , NUMTODSINTERVAL(DT2 - ADD_MONTHS( DT1, TRUNC(MONTHS_BETWEEN(DT2, DT1)) ), 'DAY') DAYS_HOURS
3 FROM (SELECT TO_DATE('29-FEB-2000 01:02:03', 'DD-MON-YYYY HH24:MI:SS') DT1,
4 TO_DATE('15-MAR-2001 11:22:33', 'DD-MON-YYYY HH24:MI:SS') DT2
5 FROM DUAL);
YEARS_MONTHS DAYS_HOURS
------------ ------------------------------
+000000001-00 +000000015 10:20:30.000000000
SQL> DROP TABLE T;
Table dropped.
SQL>
SQL> CREATE TABLE T
2 (
3 DT DATE,
4 TS TIMESTAMP(0)
5 );
Table created.
SQL>
SQL> INSERT INTO T VALUES(SYSDATE,SYSTIMESTAMP);
1 row created.
-- 데이터 타입은 다르지만 그들이 저장하는 방식은 같다
SQL> SELECT DUMP(DT,10), DUMP(TS,10) FROM T;
DUMP(DT,10) DUMP(TS,10)
--------------------- ---------------------------------------
Typ=12 Len=7: 120,114,12,10,21,47,40 Typ=180 Len=7: 120,114,12,10,21,47,41
SQL> DROP TABLE T;
Table dropped.
SQL>
SQL> CREATE TABLE T
2 (
3 DT DATE,
4 TS TIMESTAMP(9)
5 );
Table created.
-- TIMESTAMP는 11바이트 저장공간 차지, 소수점 자릿수 초단위 표현을 위해 4바이를 사용
SQL> INSERT INTO T VALUES(SYSDATE,SYSTIMESTAMP);
1 row created.
SQL> SELECT DUMP(DT,10), DUMP(TS,10) FROM T;
DUMP(DT,10) DUMP(TS,10)
-------------------------------------- ------------------------------------------
Typ=12 Len=7: 120,114,12,10,21,50,44 Typ=180 Len=11: 120,114,12,10,21,50,44,32,17,58,128
SQL> ALTER SESSION SET NLS_DATE_FORMAT = 'DD-MON-YYYY HH24:MI:SS';
Session altered.
SQL>
SQL> SELECT * FROM T;
DT TS
----------------------- -------------------------------
10-DEC-2014 20:49:43 10-DEC-14 08.49.43.538000000 PM
SQL>
SQL> SELECT DUMP(TS,16) DUMP FROM T;
DUMP
--------------------------------------------------------------------------------
Typ=180 Len=11: 78,72,c,a,15,32,2c,20,11,3a,80
-- 4바이트를 10진수로 변환하여 확인
SQL> SELECT TO_NUMBER('20113a80','xxxxxxxx') FROM DUAL;
TO_NUMBER('20113A80','XXXXXXXX')
--------------------------------
538000000
SQL> ALTER SESSION SET NLS_DATE_FORMAT = 'DD-MON-YYYY HH24:MI:SS';
Session altered.
-- DATE에 적용했던 산술연산 적용가능하다
SQL>
SQL> SELECT SYSTIMESTAMP TS, SYSTIMESTAMP+1 DT FROM DUAL;
TS DT
---------------------------------------- -----------------------------------
12-DEC-14 04.38.48.893000 PM +09:00 13-DEC-2014 16:38:48
-- SYSTIMESTAMP+1 값이 SYSTIMESTAMP 하루 후임을 주목
SQL> SELECT SYSTIMESTAMP TS, SYSTIMESTAMP+NUMTODSINTERVAL(1,'day') DT
2 FROM DUAL;
TS DT
------------------------------------------ ---------------------------------
12-DEC-14 04.41.24.407000 PM +09:00 13-DEC-14 04.41.24.407000000 PM +09:00
-- DATE와 TIMESTAMP 의 차이점은 DATA에서 DATE를 뺀 숫자
-- TIMESTAMP 에서 TIMESTAMP 를 뺀 값은 INTERVAL
SQL> SELECT DT2-DT1
2 FROM (SELECT TO_TIMESTAMP('29-FEB-2000 01:02:03.122000',
3 'DD-MON-YYYY HH24:MI:SS:FF') DT1,
4 TO_TIMESTAMP('15-MAR-2001 11:22:33.000000',
5 'DD-MON-YYYY HH24:MI:SS:FF') DT2 FROM DUAL
6 )
7 ;
DT2-DT1
---------------------------------------------------------------------------
+000000380 10:20:29.878000000
-- ADD_MONTH 를 사용하면 DT1은 묵시적으로 DATE로 변환, 소수 자릿수 초를 잃음
SQL> SELECT NUMTOYMINTERVAL(TRUNC(MONTHS_BETWEEN(DT2, DT1)), 'MONTH') YEARS_MONTHS
2 , DT2 - ADD_MONTHS(DT1, TRUNC(MONTHS_BETWEEN(DT2 ,DT1)))DAYS_HOURS
3 FROM (SELECT TO_TIMESTAMP('29-FEB-2000 01:02:03.122000', 'DD-MON-YYYY HH24:MI:SS.FF') DT1,
4 TO_TIMESTAMP('15-MAR-2001 11:22:33.000000', 'DD-MON-YYYY HH24:MI:SS.FF') DT2
5 FROM DUAL);
YEARS_MONTHS DAYS_HOURS
--------------------------- ------------------------------------------------
+000000001-00 +000000015 10:20:30.000000000
-- TRUNC(MONTHS_BETWEEN(DT2 ,DT1)) 가 12 이므로 2001.02.29 날짜는 없슴
SQL> SELECT NUMTOYMINTERVAL(TRUNC(MONTHS_BETWEEN(DT2, DT1)), 'MONTH') YEARS_MONTHS
2 , DT2 - (DT1 + NUMTOYMINTERVAL(TRUNC(MONTHS_BETWEEN(DT2 ,DT1)), 'MONTH')) DAYS_HOURS
3 FROM (SELECT TO_TIMESTAMP('29-FEB-2000 01:02:03.122000', 'DD-MON-YYYY HH24:MI:SS.FF') DT1,
4 TO_TIMESTAMP('15-MAR-2001 11:22:33.000000', 'DD-MON-YYYY HH24:MI:SS.FF') DT2
5 FROM DUAL);
, DT2 - (DT1 + NUMTOYMINTERVAL(TRUNC(MONTHS_BETWEEN(DT2 ,DT1)), 'MONTH')) DAYS_HOURS
*
ERROR at line 2:
ORA-01839: date not valid for month specified
Table dropped.
SQL>
SQL> CREATE TABLE T
2 (
3 TS1 TIMESTAMP WITH TIME ZONE,
4 TS2 TIMESTAMP WITH TIME ZONE
5 );
Table created.
SQL>
SQL> INSERT INTO T(TS1, TS2)
2 VALUES ( TIMESTAMP'2010-02-27 16:02:32.212 US/EASTERN',
3 TIMESTAMP'2010-02-27 16:02:32.212 US/PACIFIC');
1 row created.
SQL>
SQL>
SQL> COMMIT;
Commit complete.
SQL>
SQL> SELECT TS1-TS2 FROM T;
TS1-TS2
---------------------------------------------------------------------
-000000000 03:00:00.000000
-- 두지역은 3시간차이가있다.
SQL> DROP TABLE T;
Table dropped.
SQL> CREATE TABLE T
2 (
3 DT DATE,
4 TS1 TIMESTAMP WITH TIME ZONE,
5 TS2 TIMESTAMP WITH LOCAL TIME ZONE
6 );
Table created.
SQL>
SQL> INSERT INTO T(DT, TS1, TS2)
2 VALUES ( TIMESTAMP'2010-02-27 16:02:32.212 US/PACIFIC',
3 TIMESTAMP'2010-02-27 16:02:32.212 US/PACIFIC',
4 TIMESTAMP'2010-02-27 16:02:32.212 US/PACIFIC');
1 row created.
SQL>
SQL> SELECT DBTIMEZONE FROM DUAL;
DBTIMEZONE
------------
+00:00
SQL>
SQL> SELECT DUMP(DT), DUMP(TS1), DUMP(TS2) FROM T;
DUMP(DT) -- 2010-02-27 16:02:32 저장
--------------------------------------------------------------------------------
Typ=12 Len=7: 120,110,2,27,17,3,33
DUMP(TS1) -- 2010-02-28 00:02:32 (8시간+) 저장
--------------------------------------------------------------------------------
Typ=181 Len=13: 120,110,2,28,1,3,33,12,162,221,0,137,156
DUMP(TS2) -- 2010-02-28 00:02:32 (8시간+) 저장
--------------------------------------------------------------------------------
Typ=231 Len=11: 120,110,2,28,1,3,33,12,162,221,0
SQL> SELECT TS1, TS2 FROM T;
TS1
---------------------------------------------------------------------------
27-FEB-10 04.02.32.212000 PM US/PACIFIC
TS2 -- 9시간+
---------------------------------------------------------------------------
28-FEB-10 09.02.32.212000 AM
SQL> DELETE FROM T;
1 row deleted.
SQL> INSERT INTO T(DT, TS1, TS2)
2 VALUES ( TIMESTAMP'2010-04-12 16:02:32.212 US/PACIFIC',
3 TIMESTAMP'2010-04-12 16:02:32.212 US/PACIFIC',
4 TIMESTAMP'2010-04-12 16:02:32.212 US/PACIFIC');
1 row created.
SQL>
SQL> SELECT TS1, TS2 FROM T;
TS1
---------------------------------------------------------------------------
12-APR-10 04.02.32.212000 PM US/PACIFIC
TS2
---------------------------------------------------------------------------
13-APR-10 08.02.32.212000 AM
-- TIMESTAMP WITH LOCAL TIME ZONE 컬럼의 데이터를 모두 바꿀수 없다
SQL> ALTER DATABASE SET TIME_ZONE ='PST';
ALTER DATABASE SET TIME_ZONE ='PST'
*
ERROR at line 1:
ORA-30079: cannot alter database timezone when database has TIMESTAMP WITH
LOCAL TIME ZONE columns
SQL> SELECT DT2 - DT1
2 FROM (SELECT TO_TIMESTAMP('29-FEB-2000 01:02:03.122000', 'DD-MON-YYYY HH24:MI:SS.FF') DT1,
3 TO_TIMESTAMP('15-MAR-2001 11:22:33.000000', 'DD-MON-YYYY HH24:MI:SS.FF') DT2
4 FROM DUAL);
DT2-DT1
---------------------------------------------------------------------------
+000000380 10:20:29.878000000
-- EXTRACT 함수를 사용하여 다양한 정보를 구할 수 있다.
SQL> SELECT EXTRACT( DAY FROM DT2 - DT1) DAY,
2 EXTRACT( HOUR FROM DT2 - DT1) HOUR,
3 EXTRACT( MINUTE FROM DT2 - DT1) MINUTE,
4 EXTRACT( SECOND FROM DT2 - DT1) SECOND
5 FROM (SELECT TO_TIMESTAMP('29-FEB-2000 01:02:03.122000', 'DD-MON-YYYY HH24:MI:SS.FF') DT1,
6 TO_TIMESTAMP('15-MAR-2001 11:22:33.000000', 'DD-MON-YYYY HH24:MI:SS.FF') DT2
7 FROM DUAL);
DAY HOUR MINUTE SECOND
---------- ---------- ---------- ----------
380 10 20 29.878
-- INTERVAL YEAR(N) TO MONTH
-- 5년2개월의 인터벌
SQL> SELECT NUMTOYMINTERVAL(5, 'YEAR') + NUMTOYMINTERVAL(2, 'MONTH') FROM DUAL;
NUMTOYMINTERVAL(5,'YEAR')+NUMTOYMINTERVAL(2,'MONTH')
---------------------------------------------------------------------------
+000000005-02
-- 5년2개월 = 62개월
SQL> SELECT NUMTOYMINTERVAL(5 * 12 + 2, 'MONTH') FROM DUAL;
NUMTOYMINTERVAL(5*12+2,'MONTH')
---------------------------------------------------------------------------
+000000005-02
-- YEAR/MONTH INTERVAL 타입으로 변환
SQL> SELECT TO_YMINTERVAL('5-2') FROM DUAL;
TO_YMINTERVAL('5-2')
---------------------------------------------------------------------------
+000000005-02
-- NUMBER 필드변환
SQL> SELECT INTERVAL '5-2' YEAR TO MONTH FROM DUAL;
INTERVAL'5-2'YEARTOMONTH
---------------------------------------------------------------------------
+05-02
-- INTERVAL DAY TO SECOND(INTERVAL DAY(n) TO SECOND(m))
SQL> SELECT NUMTODSINTERVAL(10, 'DAY') +
2 NUMTODSINTERVAL(2, 'HOUR') +
3 NUMTODSINTERVAL(3, 'MINUTE') +
4 NUMTODSINTERVAL(2.3312, 'SECOND')
5 FROM DUAL;
NUMTODSINTERVAL(10,'DAY')+NUMTODSINTERVAL(2,'HOUR')+NUMTODSINTERVAL(3,'MINU'
---------------------------------------------------------------------------
+000000010 02:03:02.331200000
SQL>
SQL> SELECT NUMTODSINTERVAL (10*86400 + 2*3600 + 3*60 + 2.3312, 'SECOND') FROM DUAL;
NUMTODSINTERVAL(10*86400+2*3600+3*60+2.3312,'SECOND')
---------------------------------------------------------------------------
+000000010 02:03:02.331200000
SQL>
SQL> SELECT TO_DSINTERVAL('10 02:03:02.3312') FROM DUAL;
TO_DSINTERVAL('1002:03:02.3312')
---------------------------------------------------------------------------
+000000010 02:03:02.331200000
SQL>
SQL> SELECT INTERVAL '10 02:03:02.3312' DAY TO SECOND FROM DUAL;
INTERVAL'1002:03:02.3312'DAYTOSECOND
---------------------------------------------------------------------------
+10 02:03:02.331200000