--try
select a 序号,
decode(sum(decode(b,'01',c,0)),0,'无',sum(decode(b,'01',c,0))) "01",
decode(sum(decode(b,'02',c,0)),0,'无',sum(decode(b,'02',c,0))) "02",
decode(sum(decode(b,'03',c,0)),0,'无',sum(decode(b,'03',c,0))) "03"
from tb;
select a 序号,
decode(sum(decode(b,'01',c,0)),0,'无',sum(decode(b,'01',c,0))) "01",
decode(sum(decode(b,'02',c,0)),0,'无',sum(decode(b,'02',c,0))) "02",
decode(sum(decode(b,'03',c,0)),0,'无',sum(decode(b,'03',c,0))) "03"
from tb;
你帮我加上了。:)