问题
I need a function in Oracle like this.
When i giving a parameter a simple date. Then function should getting me last day of the previous month.
Example:
FunctionName(10.02.2011) Result should be 31.01.2011
FunctionName(21.03.2011) Result should be 28.02.2011
FunctionName(31.07.2011) Result should be 30.06.2011 (Even date is last day of month)
How can i do that? By the way, i never use Oracle .
回答1:
SELECT LAST_DAY(ADD_MONTHS(yourdate,-1))
回答2:
As an alternative to the other answers here, you can also find the last day of the previous month by getting the day before the first day of this month
SELECT trunc(your_date, 'MM')-1 as new_date from your_table
I would probably still recommend using last_day(add_months(xxx,-1)) but just showing an alternative.
回答3:
select LAST_DAY(ADD_MONTHS(sysdate, -1)) from dual;
format resulting date as you like (I'll leave that one for you ;)
回答4:
With this you can also get the last BUSINESS DAY of the previous month, or any other month changing the -1.
SELECT (trunc(LAST_DAY(ADD_MONTHS(sysdate,-1)), 'iw') + 4) from dual
来源：https://stackoverflow.com/questions/4957224/getting-last-day-of-previous-month-in-oracle-function