ایجاد یک بررسی عملکرد اگر یک سال یک سال جهشی است یا خیر
این عملکرد ساده سال گذشت را بررسی می کند و با یک خط کد وابسته به سال و یا درست یا غلط برمی گرداند
This simple little function is normally called by other database operation calculating age and year differences.
When you run DATEPART DAYOFYEAR and compare the number of days on 3rd March then a leap year will return one more day, which is correct, but needs to be coded around for calculating someones age.
To get around this, we append this function to one of the dates to subtract one day after February 29.
CREATE FUNCTION Dates.GetLeapYear(@Date DATETIME2) RETURNS BIT AS BEGINDECLARE @Ret BIT=(CASE WHEN DATEPART(YEAR,@Date)%4<>0 OR (DATEPART(YEAR,@Date)%100=0 AND DATEPART(YEAR,@Date)%400<>0) THEN 0 ELSE 1 END)RETURN @RetENDGO
SELECT [dbo].[GetLeapYear]('01-01-1900') [1900],[dbo].[GetLeapYear]('01-01-1901') [1901],[dbo].[GetLeapYear]('01-01-1902') [1902],[dbo].[GetLeapYear]('01-01-1903') [1903],[dbo].[GetLeapYear]('01-01-1904') [1904]
Only 1904 will return true as expected.