Objects Dependent on Replaced Functions

If a replaced function is called by another function, both functions are recompiled when called. If the interface of the replaced function does not match that in the calling function, then the calling function must be replaced, otherwise, the calling function raises an error. You can execute sp_depends on the replaced function to check for any calling objects.

For example, testfun1 is replaced to have two parameters instead of one. The calling function, testfun2, must be replaced to account for the second parameter.
create function testfun1 (@para1 int) 
    returns int 
    as 
    begin 
        declare @retval int 
        set @retval = @para1 
        return @retval 
    end 
create function testfun2 (@para int) 
    returns int 
    as 
    begin 
        declare @retval int 
        select @retval= dbo.testfun1 (@para) 
        return @retval 
    end 
create or replace function testfun1 (@para1 int,@para2 int) 
    returns int 
    as 
    begin 
        declare @retval int 
        set @retval = @para1+@para2 
        return @retval 
    end