(1)????????????ORACLE????????????????'DD-MON-YY',????'01-JAN-98'
??????????????????????ORACLE??????????????'??-??-??',????'21-8??-2003'??'21-8??-03'
(2)????????????????
????ORACLE????????to_date()
to_date()????????????to_char()????????????????
to_date??string_value , date_format??
??????????????
string_value ??????????????????????????????????????????????????????????????????????????????????????????????????
date_format????????Oracle??????????
??????????????????ORACLE??????????????????????
???????? ????????:create table student (name varchar2(10) not null primary key , enrolldate date not null);//????student??
??
insert into student values('mark',to_date('08-21-2003','MM-DD-YYYY'));
??
insert into student values('mark1',to_date('21-08-2003','DD-MM-YYYY'));
??
insert into student values('mark2','21-8??-2003');
insert into xiongxiaomin.student values('mark3','21-8??-03');
(3)????????????????
????ORACLE????????to_char()
to_char??date_value,date_format??
??????????????
date_value ????????????????????????????????????????????????????????????????????????????????????????????????????
date_format????????Oracle??????????
????enrolldate????????????????
select (to_char(enrolldate,'HH24:MI:SS'))enrolldate from student;
(4)??????ORACLE????date????????????????????????????????
1????????????????2003??8??21????????????????????
insert into student values('mark5',to_date('09:28:03','HH:MI:SS'));//????????????????????date????????????????????????????????????????????????????????????????????????????????????????
Name enrolldate
mark5 01-???? -2003 09:28:03 AM
2????????????????????2003??7??21????????????????????
insert into student values('mark6',to_date('09:28:03','HH:MI:SS'));
????????????
Name enrolldate
mark6 01-???? -2003 09:28:03 AM
insert into student values('mark8',to_date('20:28:03','HH24:MI:SS'));
3??????????????????????????????????????
insert into student values('mark9',to_date('21-08-2003
20:28:03','DD-MM-YYYY HH24:MI:SS'));//????????????????????????????????????
insert into student values('mark',to_date('21-08-2003
09:52:03','DD-MM-YYYY HH:MI:SS'));//????????????????????????????????????
??????????????????????????????????????
insert into student values('mark2','21-8??-2003'+to_date('
09:52:03','HH:MI:SS'));//????????????????
4????SQL*Plus Worksheet??????????SQL????
select * from student;
????????????????????????date????????????????????????????????????
NAME ENROLLDATE
mark 18-8?? -03
mark1 21-8?? -03
mark2 21-8?? -03
??????3????
5??????jsP??????????????select * from student order by enrolldate
????????????????????????????????????????????
JSP????????????????
6????SQL*Plus Worksheet??????????SQL????
select name,to_char(enrolldate,'DD-MM-YYYY HH:MI:SS') from student;
????????????????????????date??????????????????????????
NAME TO_CHAR(ENROLLDATE,'DD-MM-YYYYHH:MI:SS
mark 21-08-2003 12:00:00
mark1 21-08-2003 12:00:00
??????2??
??????5??6??????????????????????JSP??????????????????". 0"
7????SQL*Plus Worksheet??????????SQL????
select name,to_char(enrolldate,'DD-MM-YYYY HH24:MI:SS') from student;
????????????????????????date??????????????????????????
NAME TO_CHAR(ENROLLDATE,'DD-MM-YYYYHH24:MI:
mark 18-08-2003 17:40:20
mark1 21-08-2003 00:00:00
mark2 21-08-2003 00:00:00
??????3????
??????6??7????SELECT????"HH:MI:SS"??"HH24:MI:SS"????????????"HH"????????????????????0-12??"HH24"??24??????????????????0-23??
????????????
??insert into student values('??????',to_date('08-19-2003
13:54:05','MM-DD-YYYY HH24:MI:SS'));
ORACLE????????????????
NAME enrolldate
?????? 19-???? -2003 01:54:05 PM
??insert into student values('??????2',to_date('08-19-2003
13:54:05','MM-DD-YYYY HH:MI:SS'));//????????
????????????
insert into student values('??????2',to_date('08-19-2003 13:54:05','MM-DD
*
ERROR ?????? 1 ??:
ORA-01849: ?????????????? 1 ?? 12 ????
??????"HH"????????????"13:54:05",????????"01??54??05"
??????????????
insert into student values('??????2',to_date('08-19-2003
01:54:05','MM-DD-YYYY HH:MI:SS'));
ORACLE????????????????
NAME enrolldate
??????2 19-???? -2003 01:54:05 AM
????????????????????????????????PM??????????AM??
????????????????????????????????????"HH24"
8??????JSP??????????????select name,to_char(enrolldate,'DD-MM-YYYY HH:MI:SS') from student
????????????????(??????????SQL*Plus Worksheet??????????SQL????
select name,to_char(enrolldate,'DD-MM-YYYY HH:MI:SS') from student;????)
9????SQL*Plus Worksheet??????????SQL????
select name,to_char(enrolldate,'month dd,yyyy HH24:MI:SS') from student;
????????????????????????date??????????????????????????
NAME TO_CHAR(ENROLLDATE,'MONTHDD,YYYYHH24:MI:SS')
mark 8?? 18,2003 17:40:20
mark1 8?? 21,2003 00:00:00
mark2 8?? 21,2003 00:00:00
??????3????
10??to_char()??????'DD-MM-YYYY'??????'MM-DD-YYYY'??????'month dd,yyyy'??????????
'DD-MM-YYYY'??????21-08-2003
'month dd,yyyy'??????8?? 21,2003
11????????????????????????????????????????????????????????????MM??MI??
??SQLPlus*Worksheet????????????????????????
insert into student values('????',to_date('08:05','HH24:MM'));//08??????????????05??????????????
commit;
??????????????????????????????
NAME ENROLLDATE
???? 01-???? -2003 08:00:00 AM
select name,to_char(enrolldate,'DD-MM-YYYY HH24:MI:SS')enrolldate from
student where name='????';
NAME ENROLLDATE
???? 01-05-2003 08:00:00
?????? 1 ????
insert into student values('????2',to_date('08-19-2003
13:54:05','MM-DD-YYYY HH24:MI:SS'));
12??????Oracle??date??????????????????????????????????????????????????????????
????????????????????????????
insert into student values('??',sysdate+7);
??????????????????????????????????????????????????????????????????????????
