Validating If Date is Last Day of the Year, Month or Day

http://blog.sqlauthority.com/

For example, if a date is the last day of the Year and last day of the month, I want to display Last Day of the Year and if a date is the last date of the month and last day of the week, I want to display the last day of the week. “

Well, very interesting question and there is no such function available for the same.

However, here is the function I have written earlier for my personal use where I almost accomplish same task.

-- Example of YearDECLARE @Day DATETIME
SET @Day = '2014-12-31'SELECTCASEWHEN CAST(@Day AS DATE) = CAST(DATEADD(ms,-3,DATEADD(yy,0,DATEADD(yy,DATEDIFF(yy,0,@Day)+1,0))) AS DATE) THEN 'LastDayofYear'WHEN CAST(@Day AS DATE) = CAST(DATEADD(s,-1,DATEADD(mm, DATEDIFF(m,0,@Day)+1,0)) AS DATE) THEN 'LastDayofMonth'WHEN CAST(@Day AS DATE) = CAST(DATEADD(s,-1,DATEADD(wk, DATEDIFF(wk,0,@Day),0)) AS DATE) THEN 'LastDayofWeek'ELSE 'Day'ENDGO
-- Example of MonthDECLARE @Day DATETIME
SET @Day = '2014-06-30'SELECTCASEWHEN CAST(@Day AS DATE) = CAST(DATEADD(ms,-3,DATEADD(yy,0,DATEADD(yy,DATEDIFF(yy,0,@Day)+1,0))) AS DATE) THEN 'LastDayofYear'WHEN CAST(@Day AS DATE) = CAST(DATEADD(s,-1,DATEADD(mm, DATEDIFF(m,0,@Day)+1,0)) AS DATE) THEN 'LastDayofMonth'WHEN CAST(@Day AS DATE) = CAST(DATEADD(s,-1,DATEADD(wk, DATEDIFF(wk,0,@Day),0)) AS DATE) THEN 'LastDayofWeek'ELSE 'Day'ENDGO
-- Example of MonthDECLARE @Day DATETIME
SET @Day = '2014-05-04'SELECTCASEWHEN CAST(@Day AS DATE) = CAST(DATEADD(ms,-3,DATEADD(yy,0,DATEADD(yy,DATEDIFF(yy,0,@Day)+1,0))) AS DATE) THEN 'LastDayofYear'WHEN CAST(@Day AS DATE) = CAST(DATEADD(s,-1,DATEADD(mm, DATEDIFF(m,0,@Day)+1,0)) AS DATE) THEN 'LastDayofMonth'WHEN CAST(@Day AS DATE) = CAST(DATEADD(s,-1,DATEADD(wk, DATEDIFF(wk,0,@Day),0)) AS DATE) THEN 'LastDayofWeek'ELSE 'Day'ENDGO