行列转换的问题
[@more@]我的测试数据:
LOVE2008>select * from test;
ID NAME
---------- --------------------
1 我
1 是
1 谁
2 我
2 是
2 love2008
6 rows selected.
这个是10G的处理方法:(增加了connect_by_isleaf,CONNECT_BY_ROOT,CONNECT_BY_ISCYCLE)
select replace(name,'/','') from (
select connect_by_isleaf ll,sys_connect_by_path(name,'/') name from (
select row_number()over(partition by id order by id) c_id,name,id,
row_number()over(partition by id order by id) -1 p_id
from test
) a
connect by prior c_id=p_id and prior id=id
start with p_id=0)
where ll=1
9i的处理方法:
select max(replace(name,'/','')) from (
select id,sys_connect_by_path(name,'/') name from (
select row_number()over(partition by id order by id) c_id,name,id,
row_number()over(partition by id order by id) -1 p_id
from test
) a
connect by prior c_id=p_id and prior id=id
start with p_id=0)
group by id
备注:connect_by_root的用法是(select connect_by_root 相应列 from ....),他返回的是
相应列的根行对应此列的值。