【转】 【SQL】行列转换

【SQL】行列转换
http://space.itpub.net/519536/viewspace-609167
一、列变行
1.创建测试表test，并初始化实验数据
sec@ora10g> create table test (name_id varchar2(10), name varchar2(10));
sec@ora10g> insert into test values ('01','Andy1');
sec@ora10g> insert into test values ('01','Andy2');
sec@ora10g> insert into test values ('01','Andy3');
sec@ora10g> insert into test values ('01','Andy4');
sec@ora10g> insert into test values ('02','Steven1');
sec@ora10g> insert into test values ('02','Steven2');
sec@ora10g> insert into test values ('02','Steven3');
sec@ora10g> insert into test values ('02','Steven4');
sec@ora10g> commit;
2.查看测试表数据
sec@ora10g> select * from test order by name_id;
NAME_ID    NAME
---------- ----------------------------------------
01         Andy1
01         Andy4
01         Andy3
01         Andy2
02         Steven1
02         Steven4
02         Steven3
02         Steven2
8 rows selected.
3.我们按照name_id不同值将该表横向转换如下
SELECT     t1.name_id,
           SUBSTR (MAX (SYS_CONNECT_BY_PATH (t1.NAME, ';')), 2) NAME
      from (SELECT a.name_id, a.NAME,
                   ROW_NUMBER () OVER (PARTITION BY a.name_id ORDER BY a.NAME) rn
              from TEST a) t1
START WITH t1.rn = 1
CONNECT BY t1.name_id = PRIOR t1.name_id AND t1.rn - 1 = PRIOR t1.rn
  GROUP BY t1.name_id;
NAME_ID  &nbs