Unit
|
Valid format parameters
|
---|---|
Year
|
SYYYY, YYYY, YEAR, SYEAR, YYY, YY, Y
|
ISO Year
|
IYYY, IY, I
|
Quarter
|
Q
|
Month
|
MONTH, MON, MM, RM
|
Week
|
WW
|
IW
|
IW
|
W
|
W
|
Day
|
DDD, DD, J
|
Start day of the week
|
DAY, DY, D
|
Hour
|
HH, HH12, HH24
|
Minute
|
MI
|
1.select trunc(sysdate) from dual --2014-4-8 今天的日期爲2014-4-8
2.select trunc(sysdate, 'mm') from dual --2014-4-1 返回當月第一天.3.select trunc(sysdate,'yy') from dual --2014-1-1 返回當年第一天
4.select trunc(sysdate,'dd') from dual --2014-4-8 返回當前年月日
5.select trunc(sysdate,'yyyy') from dual --2014-1-1 返回當年第一天
6.select trunc(sysdate,'d') from dual --2014-4-7 (星期天)返回當前星期的第一天
7.select trunc(sysdate, 'hh') from dual --2014-4-8 14:00:00 當前時間爲14:41
8.select trunc(sysdate, 'mi') from dual --2014-4-8 14:41:00 TRUNC()函數沒有秒的精確
9.select trunc(123.458) from dual --123
10.select trunc(123.458,0) from dual --123
11.select trunc(123.458,1) from dual --123.4
12.select trunc(123.458,-1) from dual --120
13.select trunc(123.458,-4) from dual --0
14.select trunc(123.458,4) from dual --123.458
15.select trunc(123) from dual --123
16.select trunc(123,1) from dual --123
17.select trunc(123,-1) from dual --120