1  with article (id_link,id_art, code_egais, id_contr) as (
  2  select 1,1,10,100 from dual union all
  3  select 1,1,10,101 from dual union all
  4  select 1,1,10,101 from dual union all
  5  select 1,1,10,102 from dual union all
  6  select 1,2,20,200 from dual union all
  7  select 1,2,20,200 from dual union all
  8  select 1,2,21,201 from dual union all
  9  select 1,2,22,202 from dual union all
 10  select 1,3,30,200 from dual union all
 11  select 1,3,30,200 from dual union all
 12  select 1,3,30,201 from dual union all
 13  select 1,3,31,202 from dual)
 14  ,tt as (
 15   select id_art,code_egais,count (distinct id_contr)-1 cc from article
 16   group by id_art,code_egais
 17  )
 18  select id_art from tt
 19  group by id_art
 20  having count (distinct code_egais)>1 and sum(cc)>0
 21* order by 1
SQL> /

    ID_ART
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         3