Originally posted by DaPi
How about:
AND (B.SNOP='T03' or B.SNOP is NULL)
I tried this:

select a.ls_id, a.FL_ID, a.RM_TYPE,
b.DV_ID,
c.COD_RITMI, c.DESCR_RITMI, c.TIPO_SPAZIO
from cod_test a, dp_test b, ti_use_test c
where a.ls_id in
(select ls_id
from cod_test
where dv_id in
(select dv_id
from dp_test
where snop = 'T03'))
and a.dv_id = b.dv_id (+)
and a.rm_type = c.rm_type (+)
and a.dv_id is null


In this case I get just dv_id null (with snop='T03')
but I'd like to obtain also dv_id ='DOMESTIC WIRELINE'

Thanks in advance!