Group-by in an Oracle database
ok, I solved this by:

select * from 
(
    select id,id_operator,denumire,loc_den,str,
           row_number() over (partition by 
                     id_operator,loc_den,str order by id_operator) as no
    from rap
    where is_punct_lucru=1
    order by id_operator
)
where no&gt;1