>Is it possible to combine a query with a function into one SQL command?
>
>I have this query:
>
>

>declare @CenterLat float=47.7795
>declare @CenterLon float=-65.7191
>declare @SearchDistance float=250
>
>select * from test
> where (latitude>=@CenterLat - @SearchDistance/111.0 and latitude<=@CenterLat + @SearchDistance/111.0) and
> (longitude>=@CenterLon - @SearchDistance/111.0 and longitude<=@CenterLon + @SearchDistance/111.0)
> and dbo.CalculateDistance(@CenterLon, @CenterLat, Longitude, Latitude) <=@SearchDistance
>

>
>I have this function:
>
>

>ALTER FUNCTION [dbo].[CalculateDistance]
>    (@Longitude1 DECIMAL(8,5), 
>    @Latitude1   DECIMAL(8,5),
>    @Longitude2  DECIMAL(8,5),
>    @Latitude2   DECIMAL(8,5))
>RETURNS FLOAT
>AS
>BEGIN
>DECLARE @Temp FLOAT
> 
>SET @Temp = SIN(@Latitude1/57.2957795130823) * SIN(@Latitude2/57.2957795130823) + 
> COS(@Latitude1/57.2957795130823) * COS(@Latitude2/57.2957795130823) * COS(@Longitude2/57.2957795130823 -
> @Longitude1/57.2957795130823)
> 
>IF @Temp > 1 
>    SET @Temp = 1
>ELSE IF @Temp < -1
>    SET @Temp = -1
> 
>RETURN (3958.75586574 * ACOS(@Temp) ) 
>

>
>If it is possible, what kind of syntax can I use to combine all this into one SQL command?


Sure, you could use it that way:

select *, dbo.CalculateDistance(.....) AS Distance
       from test
WHERE ...

--- or
select *
       from test
WHERE ... AND dbo.CalculateDistance(.....) BETWEEN .... AND ....

UPDATE:
After reading your post one more time, I'm not so sure that I'm understanding your question right :o))