oracle 获取Oracle中两个日期之间的天数，包括日期
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Get the number of days between two dates in Oracle, inclusive of the dates
提问by user968441
I want to get total number of days between two provided dates. I've tried the below query but didn't get the exact different; the last date is not being included.
我想获得两个提供的日期之间的总天数。我试过下面的查询，但没有得到完全不同的；不包括最后日期。
select (to_date ('15-06-13','dd-MM-yyyy') - to_date('01-02-12','dd-MM-yyyy'))
from dual
This should return 501 days but it is returning 500 days instead. If I add +1 after calculation, then I'm getting the correct result.
这应该返回 501 天，但它返回 500 天。如果我在计算后加上 +1，那么我会得到正确的结果。
Do I really need to include +1 or is there an alternate approach to get the actual result?
我真的需要包含 +1 还是有其他方法来获得实际结果？
回答by krokodilko
In Oracle substracting two dates returns the number of days between two dates.
A minusoperator works in the same way as for numbers:
在 Oracle 中减去两个日期返回两个日期之间的天数。
一个minus操作符以同样的方式作为数字：
20 - 20 = 0 ===> 2013-05-20 - 2013-05-20 = 0
25 - 20 = 5 ===> 2013-05-25 - 2013-05-20 = 5
If you want to include last numberor last date, you need to add 1:
如果要包含last number或last date，则需要添加 1：
20 - 20 + 1 = 1 ===> 2013-05-20 - 2013-05-20 + 1 = 1
25 - 20 + 1 = 6 ===> 2013-05-25 - 2013-05-20 + 1 = 6
