Calculating timespan with t-sql

Question

Given two date/times:

@start_date = \'2009-04-15 10:24:00.000\'
@end_date = \'2009-04-16 19:43:01.000\'

Is it possible to calculate the tim

Answer 1

I know this thread is older and the original participants are likely no longer watching, but I stumbled upon it, and had already written some code fairly recently to do something very close to what jdiaz is requesting. The result is rendered as a string in D:H:M:S format.

Step one would be to get the time span in seconds:

DECLARE @ElapsedS INT
SET @ElapsedS = DATEDIFF(second, @start_date, @end_date)

Now create the following scalar function:

CREATE FUNCTION [dbo].[udfTimeSpanFromSeconds]
(
    @Seconds int
)
RETURNS varchar(15)
AS
BEGIN
DECLARE 
    --Variable to hold our result
      @DHMS varchar(15)
    --Integers for doing the math
    , @Days int --Integer days
    , @Hours int --Integer hours
    , @Minutes int --Integer minutes
    --Strings for providing the display
    , @sDays varchar(5) --String days
    , @sHours varchar(2) --String hours
    , @sMinutes varchar(2) --String minutes
    , @sSeconds varchar(2) --String seconds

--Get the values using modulos where appropriate
SET @Hours = @Seconds/3600
SET @Minutes = (@Seconds % 3600) /60
SET @Seconds = (@Seconds % 3600) % 60

--If we have 24 or more hours, split the @Hours value into days and hours
IF @Hours > 23 
BEGIN
    SET @Days = @Hours/24
    SET @Hours = (@Hours % 24)
END
ELSE
BEGIN
    SET @Days = 0
END

--Now render the whole thing as string values for display
SET @sDays = convert(varchar, @Days)
SET @sHours = RIGHT('0' + convert(varchar, @Hours), 2)
SET @sMinutes = RIGHT('0' + convert(varchar, @Minutes), 2)
SET @sSeconds = RIGHT('0' + convert(varchar, @Seconds), 2)

--Concatenate, concatenate, concatenate
SET @DHMS =  @sDays + ':' + @sHours + ':' + @sMinutes + ':' + @sSeconds

RETURN @DHMS

END

Now feed your timespan into the newly created function:

SELECT TimeSpan = dbo.udfTimeSpanFromSeconds(@ElapsedS)

Should produce '1:09:19:01'

Answer 2

You can get the difference between the two dates to whatever resolution you want (in your example, minutes):

DATEDIFF(minute, @start_date, @end_date)

From there it's a simple matter of dividing minutes into hours and hours into days and modding the remainder.

Answer 3

datediff(datepart, date1, date2);

Rex's answer is more complete.

Answer 4

DECLARE @FirstDate DATETIME, @SecondDate DATETIME, @result VARCHAR(MAX)
SELECT @FirstDate = '2017-03-01 09:54:00.637', @SecondDate = GETDATE()

DECLARE @Day INT,@Month INT,@Hour INT, @Minute INT,@TotalSeconds INT,@Year INT
SELECT @TotalSeconds = ABS(DATEDIFF(SECOND,@FirstDate,@SecondDate))

-- Standard values in seconds
DECLARE @YearSeconds INT, @MonthSeconds INT, @DaySeconds INT, @HourSeconds INT, @MinuteSeconds INT

SELECT  @MinuteSeconds = 60
SELECT  @HourSeconds = 60 * @MinuteSeconds 
SELECT  @DaySeconds = 24 * @HourSeconds
SELECT  @MonthSeconds = 30 * @DaySeconds
SELECT  @YearSeconds = 12 * @MonthSeconds

--SELECT @MinuteSeconds AS [Minutes], @HourSeconds AS [Hours], @DaySeconds AS [Day],@MonthSeconds AS [Month],@YearSeconds AS [Year]

IF @TotalSeconds < @MinuteSeconds
BEGIN
    SELECT @result = CAST(@TotalSeconds AS NVARCHAR(20)) + ' seconds ago' 
END
ELSE IF @TotalSeconds < @HourSeconds
BEGIN
    SELECT @result = CAST(ABS(DATEDIFF(MINUTE,@FirstDate,@SecondDate)) AS NVARCHAR(20)) + ' minutes ago' 
END
ELSE IF @TotalSeconds < @DaySeconds
BEGIN
    SELECT @result = CAST(ABS(DATEDIFF(HOUR,@FirstDate,@SecondDate)) AS     NVARCHAR(20)) + ' hours ago' 
END
ELSE IF @TotalSeconds < @MonthSeconds
BEGIN
    SELECT @result = CAST(ABS(DATEDIFF(DAY,@FirstDate,@SecondDate)) AS NVARCHAR(20)) + ' days ago' 
END
ELSE IF @TotalSeconds < @YearSeconds
BEGIN
    SELECT @result = CAST(ABS(DATEDIFF(MONTH,@FirstDate,@SecondDate)) AS NVARCHAR(20)) + ' months ago' 
END
ELSE IF @TotalSeconds > @YearSeconds
BEGIN
    SELECT @result = CAST(ABS(DATEDIFF(YEAR,@FirstDate,@SecondDate)) AS NVARCHAR(20)) + ' year ago' 
END


SELECT @result

Answer 5

DATEDIFF can return unintuitive values. For example, the two dates below differ by one second yet DATEDIFF with the parameters below and interpreted as others have interpreted it above returns 1 year:

SELECT DATEDIFF(year, '2005-12-31 23:59:59', '2006-01-01 00:00:00')

Look at the MSDN documentation for DATEDIFF to understand how it works.

Answer 6

Here's how you format the datediff (50d 8h 35m) in a query:

Declare @Date1 as Datetime, @Date2 as Datetime
Set @Date1 = '2005-01-01 08:00:00'
Set @Date2 = '2005-02-20 16:35:30'

Select
CAST(DATEDIFF(Minute,@Date1, @Date2)/60/24 as Varchar(50)) ++ 'd ' ++ 
CAST((DATEDIFF(Minute,@Date1, @Date2)/60)-((DATEDIFF(Minute,@Date1, @Date2)/60/24)*24) as Varchar(50)) ++ 'h ' ++
CAST((DATEDIFF(Minute,@Date1, @Date2)) - (DATEDIFF(HOUR,@Date1, @Date2)*60) as Varchar(50)) ++ 'm' as FormattedDateDiff