oracle 行列轉換 （http://blog.163.com/xiao_maomao_chong/blog/static/3168623920086445319803/）
筆 試 2008-07-04 16:53:19 閱讀118 評論0 字號：大 中 小
有一個字符串
,1,2,5,9,1,2,5,9,1,3,9,
通
過SQL文將以上字符串處理後得到如下查詢結果：
col
1
2
5
9
1
2
5
9
1
3
9
with tbl2 as (
select
',1,2,5,9,1,2,5,9,1,3,9,22,25,10,155555,' as temp from dual
)
select
substr(temp,currentIndex,nextIndex-currentIndex) as cols from
(
select temp
,level lv
,instr(temp,',',instr(temp,','),level)+1 as currentIndex
,instr(temp,',',instr(temp,','),level+1) as nextIndex from
(
select temp
,length(temp)- length(replace(temp,','))-1
rowcnt
from tbl2
) a
connect by level
<= rowcnt
)
挑戰無處不在~~
with tbl2 as (
select
',1,2,5,9,1,2,5,9,1,3,9,' as temp from dual
)
select
substr(temp2,lv,1) from
(
select temp2,level lv from
(
select temp,replace(temp,',')
temp2,length(replace(temp,',')) rowcnt from tbl2
) a
connect by level <= rowcnt
)
select DECODE('A', '01'
,'WO JIAO DDDD', 'EEEE' , '02', '55' )
AS LIU from
(
select
SUBSTR(mid,1,2)
as a,
SUBSTR(mid,4,2) as b,
SUBSTR(mid,7,2) as c,
SUBSTR(mid,10,2)
as d,
SUBSTR(mid,13,2) as e
from liu )
**********************************************************************************
select DECODE(a, '01' ,b, '02' , c, d )
AS LIU from
(
select
SUBSTR(mid,1,2)
as a,
SUBSTR(mid,4,2) as b,
SUBSTR(mid,7,2) as c,
SUBSTR(mid,10,2)
as d,
SUBSTR(mid,13,2) as e
from liu )
with
tbl2 as (
select wmsys.wm_concat(mid) as temp from liu
)
select
substr(temp,currentIndex,nextIndex-currentIndex) as cols from
(
select temp
,level lv
,instr(temp,',',instr(temp,','),level)-2 as currentIndex
,instr(temp,',',instr(temp,','),level) as nextIndex from
(
select temp
,length(replace(temp,','))/2 rowcnt
from tbl2
) a
connect by level <= rowcnt
)