Oracle 日期加减操作
oracle 日期加减方法 2011-04-18 08:40 加法 select sysdate,add_months(sysdate,12) from dual; -- 加 1 年 select sysdate,add_months(sysdate,1) from dual; -- 加 1 月 select sysdate,to_char(sysdate7,'yyyy-mm-dd HH24:MI:SS') from dual; -- 加 1 星
oracle
日期加减方法
2011-04-18 08:40
加法
select sysdate,add_months(sysdate,12) from dual;
--
加
1
年
select sysdate,add_months(sysdate,1) from dual;
--
加
1
月
select sysdate,to_char(sysdate+7,'yyyy-mm-dd HH24:MI:SS') from dual;
--
加
1
星期
select sysdate,to_char(sysdate+1,'yyyy-mm-dd HH24:MI:SS') from dual;
--
加
1
天
select sysdate,to_char(sysdate+1/24,'yyyy-mm-dd HH24:MI:SS') from dual;
--
加
1
小时
select sysdate,to_char(sysdate+1/24/60,'yyyy-mm-dd HH24:MI:SS') from dual;
--
加
1
分钟
select sysdate,to_char(sysdate+1/24/60/60,'yyyy-mm-dd HH24:MI:SS') from dual;
--
加
1
秒
减法
select sysdate,add_months(sysdate,-12) from dual;
--
减
1
年
select sysdate,add_months(sysdate,-1) from dual;
--
减
1
月
select sysdate,to_char(sysdate-7,'yyyy-mm-dd HH24:MI:SS') from dual;
--
减
1
星期
select sysdate,to_char(sysdate-1,'yyyy-mm-dd HH24:MI:SS') from dual;
--
减
1
天
select sysdate,to_char(sysdate-1/24,'yyyy-mm-dd HH24:MI:SS') from dual;
--
减
1
小时
select sysdate,to_char(sysdate-1/24/60,'yyyy-mm-dd HH24:MI:SS') from dual;
--
减
1
分钟
select
sysdate,to_char(sysdate-1/24/60/60,'yyyy-mm-dd
HH24:MI:SS')
from
dual;
--
减
1
秒
日期与日期之间不能相加
日期与数字就可相加
SQL>
select
sysdate+1
from
dual;
日期与日期可以相减
SQL>
select
sysdate-sysdate
from
dual;
Add_Months
(
D
,
X
)
返回
D
日期加上
X
个月后的日期
Last_Day
(
D
)
返回包含日期
D
的月份的最后一天的日期
add_months(sysdate,1)
加一个月
add_months(sysdate,-1)
减一个月
sysdate+1
加一天
-------------------------------------------------------------------------------
Months_Between
(
D1
,
D2
)
返回
D1
、
D2
之间的月份数目
New_Time
(
D
,
Z1
,
Z2
)
返回时区
Z1
里时间为
D
时
Z2
时区的时间
Next_Day
(
D
,
S
)
返回满足条件
S
的下一天
S
为星期几
Round
(
D
,
F
)
日期
D
按照格式
F
进行舍入
Sysdate
返回数据库当前时间
Trunc
(
D
,
F
)
按照格式
F
截断时间
D
另外:日期可以直接加减
如:
sysdate
+1,sysdate
-1
------------------------------------------------------------
sysdate+1
加一天
sysdate+1/24
加
1
小时
sysdate+1/(24*60)
加
1
分钟
sysdate+1/(24*60*60)
加
1
秒钟

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