select max(decode(r2,1,a,null)),max(decode(r2,1,b,null)),
max(decode(r2,0,a,null)),max(decode(r2,0,b,null))
from (
select round(rownum/2) r1,mod(rownum,2) r2, a,b from t1
)
group by r1
max(decode(r2,0,a,null)),max(decode(r2,0,b,null))
from (
select round(rownum/2) r1,mod(rownum,2) r2, a,b from t1
)
group by r1
max(decode(r2,0,a,null)),max(decode(r2,0,b,null))
from (
select ceil(rownum/2) r1,mod(rownum,2) r2, a,b from t1
)
group by r1把round 改为 ceil 更通用一些。
decode(r2,0,a,null),decode(r2,0,b,null)
from (
select mod(rownum,2) r2, a,b from t1
)
我认为这样就可以了,
decode(ab.r2,0,ab.a,null),decode(ab.r2,0,ab.b,null)
from (
select mod(rownum,2) r2, a,b from t1
) ab
order by aa,bb