SQL Server Function to merge a date with a time

I use this when I need to join two fields. One has a date, the other has a time.

 IF  EXISTS (SELECT * FROM sys.objects WHERE object_id = OBJECT_ID(N'[util].[uf_MergeDate2Time]') AND type in (N'FN', N'IF', N'TF', N'FS', N'FT'))

 DROP FUNCTION [util].[uf_MergeDate2Time]

GO

 CREATE FUNCTION [util].[uf_MergeDate2Time](

       @date            DATETIME,

       @time            DATETIME

 RETURNS DATETIME

 WITH EXECUTE AS CALLER

AS

 /**********************************************************************************************************

 * UDF Name:

 *        [util].[uf_MergeDate2Time]

 * Parameters:

 *         @date            datetime - The date to merge

          @time            datetime - The time to merge

 * Purpose: This function returns a datetime of the @date variable concatendated to the @time variable.

 * Example:

     select [util].[uf_MergeDate2Time]('12/25/2007', GETDATE())

 * Revision Date/Time:

 *    November 1, 2007

 **********************************************************************************************************/

 BEGIN

     -- declare variables

     DECLARE @result datetime;

     -- determine half year date

     SET @result = CAST(LEFT(CONVERT(NVARCHAR(40), @date, 121), 10) + ' ' + RIGHT(CONVERT(NVARCHAR(40), @time, 121), 12) AS DATETIME)

 RETURN @result;

 END;

GO

 SELECT [util].[uf_MergeDate2Time]('2007-12-25', GETDATE());

GO

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