数据查询时，无记录显示0,该怎么解决

数据查询时，无记录显示0
select id from t_table where id in (1,2,3);
表为 
idname
1aa
2bb

想显示的结果为
1
2
0


[解决办法]

SQL code

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
[解决办法]
SQL code
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