sql - 使用一列的结果来制作列名

Question

我有选择语句，例如:

select trim(time), type, count(1) from table                             
group by trim(time),type

结果是:

02.10.13    REZ1    1

02.10.13    REZ2    5

02.10.13    REZ3    3

是否可以使用一些 Oracle 函数进行一些 select 语句以获得以下结果:

REZ1    REZ2    REZ3

1       5       3

因此，一列的结果是另一条语句中的列名，例如:

select ?SOMETHING? 
from (
select trim(time), type, count(1) 
from table                             
group by trim(time),type) s

Answer 1

WITH t(l_date, val, l_count)
AS
(SELECT to_date('02.10.13', 'dd.mm.yy'), 'REZ1'   , 1 FROM dual UNION
SELECT to_date('02.10.13', 'dd.mm.yy'), 'REZ2'   , 5 FROM dual UNION
SELECT to_date('02.10.13', 'dd.mm.yy'), 'REZ3'   , 3 FROM dual 
)

SELECT *
FROM
     ( SELECT  val, l_count FROM   t
     ) PIVOT (MAX(l_count) FOR (val) IN ('REZ1' REZ1,'REZ2' REZ2 ,'REZ3' REZ3));