with
	e1 as (
		select
			emp_last_name
			,emp_first_name
			,replace(emp_last_name, ' ', '') as ln
			,replace(emp_first_name, ' ', '') as fn
			,emp_code as code
		from
			emp
		where
			valid_flg = 1
	)
	,e2 as (
		select
			replace(emp_last_name, ' ', '') as ln
			,replace(emp_first_name, ' ', '') as fn
			,emp_code as code
		from
			emp
	)

select
	e1.code as CODE
	,e1.emp_last_name as SURNAME
	,e1.emp_first_name as NAME
from
	e1
	join
		e2
	on
		e1.code != e2.code
		and e1.ln = e2.ln
		and e1.fn = e2.fn
order by
	2, 3, 1