Comments on: Round DATETIME to nearest X minute increment http://www.ideaexcursion.com/2008/08/15/round-datetime-to-nearest-x-minute-increment/ Technology Musings Sat, 04 Feb 2012 00:04:25 +0000 hourly 1 http://wordpress.org/?v=3.3.1 By: Rob Owenhttp://www.ideaexcursion.com/2008/08/15/round-datetime-to-nearest-x-minute-increment/comment-page-1/#comment-538 Rob Owen Mon, 23 May 2011 23:39:56 +0000 http://www.ideaexcursion.com/?p=4#comment-538 An error is caused by float. Try this on the time 15:12 for example.I changed the convert function toselect dateadd(day, 0, datediff(day, 0, @time)) + convert(datetime, convert(decimal(12, 7), (round(cast(cast(convert(varchar(12), @time, 14) as datetime) as float) * 1440.0 / @min, 0) / (1440.0 / @min)))) An error is caused by float. Try this on the time 15:12 for example.

I changed the convert function to

select dateadd(day, 0, datediff(day, 0, @time))
+ convert(datetime, convert(decimal(12, 7), (round(cast(cast(convert(varchar(12), @time, 14) as datetime) as float) * 1440.0 / @min, 0) / (1440.0 / @min))))

]]> By: Gerhard Schmeusserhttp://www.ideaexcursion.com/2008/08/15/round-datetime-to-nearest-x-minute-increment/comment-page-1/#comment-396 Gerhard Schmeusser Sun, 28 Mar 2010 08:30:25 +0000 http://www.ideaexcursion.com/?p=4#comment-396 The mentioned rounding error occured very often when I read data from a linked server. I therefore implemented a different solution:create function dbo.fnrounddatetominutes ( @date smalldatetime -- rounds to minutes , @minutesBoundary smallint -- must be between 1 and 60 ) returns smalldatetime as begindeclare @rest int set @rest = datepart(minute, @date) % @minutesBoundaryreturn case when @rest = 0 then @date when @rest < ((@minutesBoundary + 1) / 2) then dateadd(minute, -@rest, @date) else dateadd(minute, @minutesBoundary-@rest, @date) end end go The mentioned rounding error occured very often when I read data from a linked server. I therefore implemented a different solution:

create function dbo.fnrounddatetominutes
(
@date smalldatetime — rounds to minutes
, @minutesBoundary smallint — must be between 1 and 60
)
returns smalldatetime
as
begin

declare @rest int
set @rest = datepart(minute, @date) % @minutesBoundary

return
case
when @rest = 0 then @date
when @rest < ((@minutesBoundary + 1) / 2) then dateadd(minute, -@rest, @date)
else dateadd(minute, @minutesBoundary-@rest, @date)
end

end
go

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