Question

我现在已经在这个问题上遇到了一段时间，并且没有取得任何进展。我甚至不知道是否可能......

我有一张桌子：

+------+------------+-------+---------+------------+
| Item |    Date    | RUnit | FDHUnit | Difference |
+------+------------+-------+---------+------------+
| A    | 19/04/2016 | 21000 |   20000 |       1000 |
| B    | 20/04/2016 |  2500 |     500 |       2000 |
+------+------------+-------+---------+------------+

是否可以在同一个表格中为每个items创建一个新行，这些行将显示Difference以及其他一些列？

我想要的输出是这样的：

+------+------------+-------+---------+------------+
| Item |    Date    | RUnit | FDHUnit | Difference |
+------+------------+-------+---------+------------+
| A    | 19/04/2016 | 21000 | 20000   |            |
| A    | 19/04/2016 | NULL  | NULL    |       1000 |
| B    | 20/04/2016 | 2500  | 500     |            |
| B    | 20/04/2016 | NULL  | NULL    |       2000 |
+------+------------+-------+---------+------------+

原因是我希望显示一个新列，并指出它是Held directly或not held directly。

Answer 1

是的，请使用union all：

select item, date, ruunit, fdhunit, difference
from t
union all
select item, date, null, null, runit - fdhunit
from t
order by item, (case when runit is not null then 1 else 2 end);

order by将结果按照结果显示的顺序排列。没有order by，记录的顺序是不确定的。

Answer 2

试试这种方式

select * from 
(select item, date, ruunit, fdhunit, '' as difference
from t
union all
select item, date, null as ruunit, null as fdhunit, difference
from t) a
order by item, date

Answer 3

试试这个

插入表格：

insert into table1 
select item,date,null,null,(Runit-fdhunit) from table1 where (Runit-fdhunit)

正常结果：从table1中选择* 联合所有从table1中选择item，date，null，null，（Runit-fdhunit）其中（Runit-fdhunit）＆lt;＆gt; 0

Answer 4

试试这个。将cast(null as number)替换为difference列的实际类型

select item, date, r.ruunit, r.fdhunit, r.difference
from t
cross apply ( 
   select n=1, ruunit, fdhunit, cast(null as number) difference
   UNION  
   select n=2, null, null, difference ) r
order by item, date, n

如何在同一个表中复制记录

4 个答案: