Datetime SQL Sentence

I have the following SP which works ok but not between 00:00 and 23:59:59

CREATE PROCEDURE dbo.GetFechaVencimiento
@CantDiasDesde smallint,
@CantDiasHasta smallint
AS
DECLARE @datDesde datetime
DECLARE @datHasta datetime
SET NOCOUNT ON;
SET @datDesde=dateadd(day, @CantDiasDesde, getdate())
SET @datHasta=dateadd(day, @CantDiasHasta,getdate())
SELECT fchr,descr,mbox_env,fvenc FROM mer WHERE fvenc>=@datDesde and fvenc<=@datHasta ORDER BY fvenc
GO

This SP gets the date at the same time, thus not giving me any chance to get one record. This is why I need to conserve the date but not the time.

Hope this is clear to help me to figure this out,

Marcelo.

Something like this will remove time from the date...

Code:

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DECLARE @datDesde datetime
DECLARE @datHasta datetime
DECLARE @DateOnly datetime
SET NOCOUNT ON;
Set @DateOnly=Cast(Convert(Char(10),GetDate(),101) as datetime)
SET @datDesde=dateadd(day, @CantDiasDesde, @DateOnly)
SET @datHasta=dateadd(day, @CantDiasHasta,@DateOnly)
SELECT fchr,descr,mbox_env,fvenc FROM mer WHERE fvenc>=@datDesde and fvenc<=@datHasta ORDER BY fvenc

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