Oracle ???????? ??? ????? ?? ??? ??
Oracle ??????? ? ????? ?? ??? ??? ????? ???? ??? ??? ?? ??? ???? ???? ???.
? ?? TIMESTAMP ??? ?? ??? INTERVAL DAY TO SECOND ????. ? ???? ???????? ???? ?? ??? ?? ?? ?? ??? ?/?? ?????? ?????. ?? ?? Windows ?? ??????? ????? ???? ???? ?? Unix ?? ??????? ?????? ???? ??? ????.
?? ???? ??
INTERVAL DAY TO SECOND ??? ?? ?? ?? ??? ????? EXTRACT ??? ??? ? ????. ? ??? ???? ?, ??, ?, ?? ?? ?? ??? ??? ? ????.
? ??? ??
????? ??? ? ??? ?? ??? ?? ??? ? ?? ??? ??? ? ??? ??? ? ????. ??? INTERVAL DAY TO SECOND ??? ????? ??, ?, ?? ?? ?? ?? ???? ?? ? ???? ??? ????.
?? ?:
?? ?? ??? ???.
select systimestamp - to_timestamp('2012-07-23', 'yyyy-mm-dd')
from dual;
? ??? ??? INTERVAL DAY TO SECOND ??? ?????.
<code>+000000000 14:51:04.339000000</code>
EXTRACT ??? ???? ?, ?, ?, ? ?? ??? ??? ? ????.
select extract(day from diff) days,
extract(hour from diff) hours,
extract(minute from diff) minutes,
extract(second from diff) seconds
from (select systimestamp - to_timestamp('2012-07-23', 'yyyy-mm-dd') diff
from dual);
??? ??? ????.
<code> DAYS HOURS MINUTES SECONDS
---------- ---------- ---------- ----------
0 14 55 37.936</code>
? ???? ???? ?? ?? ?? ??? ?????.
select extract(day from diff)*24*60*60*1000 +
extract(hour from diff)*60*60*1000 +
extract(minute from diff)*60*1000 +
round(extract(second from diff)*1000) total_milliseconds
from (select systimestamp - to_timestamp('2012-07-23', 'yyyy-mm-dd') diff
from dual);
?? ??:
<code>TOTAL_MILLISECONDS
------------------
53831842</code>? ??? Oracle?? ????? ?? ??? ??? ???? ??? ??????? ?? ?????. ??? ??? PHP ??? ????? ?? ?? ??? ?????!
? AI ??
Undress AI Tool
??? ???? ??
Undresser.AI Undress
???? ?? ??? ??? ?? AI ?? ?
AI Clothes Remover
???? ?? ???? ??? AI ?????.
Clothoff.io
AI ? ???
Video Face Swap
??? ??? AI ?? ?? ??? ???? ?? ???? ??? ?? ????!
?? ??
??? ??
???++7.3.1
???? ?? ?? ?? ???
SublimeText3 ??? ??
??? ??, ???? ?? ????.
???? 13.0.1 ???
??? PHP ?? ?? ??
???? CS6
??? ? ?? ??
SublimeText3 Mac ??
? ??? ?? ?? ?????(SublimeText3)
??? ??
8646
17
1787
16
1730
56
1582
29
1451
31
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?? ?? ??? ?? ?? MySQL ?? ?? ?? ??
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MySQL ? ? ???? NULL ?? ?????
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