sql – Oracle将多个列合并为一个

关于Oracle Sql,我有一个问题,

如果我有一个名为A的数据,有8列:

Spot| ID |Sunday|Monday|Tuesday|Wednesday|Thursday|Friday|Saturday 
-------------------------------------------------------------------------
   A| 1  | 0.1  |0.15  | ...........................................
-------------------------------------------------------------------------
   A| 2  | 0.2  |0.2   | ...........................................
-------------------------------------------------------------------------
   A| 3  | 0.3  |0.25  | ...........................................
-------------------------------------------------------------------------
   A| 4  | 0.4  |0.4   | ...........................................
-------------------------------------------------------------------------

我可以将它转换为表格B,如下所示:

Spot| Day of Week  | ID | Value 
-------------------------------------------------------------------------
   A| 1            | 1  |  0.1 
-------------------------------------------------------------------------
   A| 1            | 2  |  0.2 
-------------------------------------------------------------------------
   A| 1            | 3  |  0.3 
-------------------------------------------------------------------------
   A| 1            | 4  |  0.4 
-------------------------------------------------------------------------
   A| 2            | 1  |  0.15
-------------------------------------------------------------------------
 .......................................................................

将列(星期日到星期六)组合到一个名为“星期几”的新列中

我该怎么办?谢谢!

你可以使用UNPIVOT:

Oracle安装程序:

CREATE TABLE your_table ( spot, id, sunday, monday, tuesday, wednesday, thursday, friday, saturday ) AS
  SELECT 'A', 1, 0.1, 0.15, 0.2, 0.25, 0.3, 0.35, 0.4 FROM DUAL UNION ALL
  SELECT 'A', 2, 0.15, 0.2, 0.25, 0.3, 0.35, 0.4, 0.45 FROM DUAL UNION ALL
  SELECT 'A', 3, 0.2, 0.25, 0.3, 0.35, 0.4, 0.45, 0.5 FROM DUAL;

查询:

SELECT *
FROM   your_table
UNPIVOT ( Value FOR Day_of_week IN (
  sunday    AS 1,
  monday    AS 2,
  tuesday   AS 3,
  wednesday AS 4,
  thursday  AS 5,
  friday    AS 6,
  saturday  AS 7
 ) );

输出:

S ID DAY_OF_WEEK VALUE
- -- ----------- -----
A  1           1    .1
A  1           2   .15
A  1           3    .2
A  1           4   .25
A  1           5    .3
A  1           6   .35
A  1           7    .4
A  2           1   .15
A  2           2    .2
A  2           3   .25
A  2           4    .3
A  2           5   .35
A  2           6    .4
A  2           7   .45
A  3           1    .2
A  3           2   .25
A  3           3    .3
A  3           4   .35
A  3           5    .4
A  3           6   .45
A  3           7    .5
https://stackoverflow.com/questions/44596946/oracle-combine-several-columns-into-one

本站文章除注明转载外,均为本站原创或编译
转载请明显位置注明出处:sql – Oracle将多个列合并为一个