select aa.rn,nvl(bb.id,0) as id from (select rn from (select rownum as rn from dual connect by rownum<=9) a where a.rn in(1,2,3) ) aa left join t_table bb on aa.rn=bb.id
select nvl(t.id,0) from (select rownum as rn from t connect by rownum<=2) a left join t on t.id=a.rn
select id from t_table where id in (1,2,3) union all select 0
select aa.rn,nvl(bb.id,0) as id from
(select rn from
(select rownum as rn from dual connect by rownum<=9) a
where a.rn in(1,2,3)
) aa left join t_table bb on aa.rn=bb.id
(select rownum as rn from t connect by rownum<=2) a left join t on t.id=a.rn
union all
select 0