Update only time from my Datetime field in sql

Question

I have a date 2013-12-14 05:00:00.000 in my table.

Now i want to update only time of that date. E.G to 2013-12-14 04:00:00.000

Is there any query to update o

Answer 1

use this script:

declare @curDate datetime=getdate() --or any other datetime 
declare @time time='22:31'
declare @hour int ,@min int
set @hour=datepart(hh,@time)
set @min=datepart(mm,@time)
select @curDate=Dateadd(HOUR,@hour,convert(datetime,convert(Date,@curDate)))
select @curDate=Dateadd(MINUTE,@min,@curDate)
Select @curDate