--我寫的這個有點復雜,等高人幫你寫個簡單的吧
with t(id,score) as(
select 1,55 from dual
union all select 1,65 from dual
union all select 1,80 from dual
union all select 2,60 from dual
union all select 2,65 from dual
union all select 2,88 from dual
)
select
    id,
    max(decode(rn,1,score,0)) s1,
    max(decode(rn,2,score,0)) s2,
    max(decode(rn,3,score,0)) s3
from (select row_number() over(partition by id order by id) rn,id,score from t) 
group by id;
/*
        ID         S1         S2         S3                                     
---------- ---------- ---------- ----------                                     
         1         55         65         80                                     
         2         60         65         88   
*/

------解决方案--------------------

with t(id,score) as(
select 1,55 from dual
union all select 1,65 from dual
union all select 1,80 from dual
union all select 2,60 from dual
union all select 2,65 from dual
union all select 2,88 from dual
)
SELECT * FROM (select id as fid,score,row_number()over(partition by id order by id) as rn from t ) t1
pivot(SUM(score) FOR rn IN (1,2,3))


FID                    1                      2                      3                     
---------------------- ---------------------- ---------------------- ----------------------  
1                      55                     65                     80                    
2                      60                     65                     88