FIRST EXAMPLE--CREATE FUNCTION dbo.myFunction()
RETURNS INT
AS
BEGIN
DECLARE @myInt INT
SET @myInt = 1
RETURN @myInt
END

select dbo.myFunction() as 'Simple Number'

This Function is not returning any value,Error is coming
Cannot find either column "dbo" or the user-defined function or aggregate "dbo.myFunction", or the name is ambiguous.


SECOND EXAMPLE--
create function dbo.add1(@num1 Int,@num2 Int)
Returns INT
as
Begin
Return(@num1+@num2)
End

select dbo.add1(10,20) as result

Above function is working fine,but dbo is optional IF I write the above Function without dbo
create function add1(@num1 Int,@num2 Int)
Returns INT
as
Begin
Return(@num1+@num2)
End

select add1(10,20) as result
Then the Function is Contructed successfully , But when I call the function usimg Select statement
Error is there--
'add1' is not a recognized built-in function name.

Plz reply whether its necessary to write owner name to prevent errors.