查询在另一列中没有相同值的列

Question

我的Table

ItemCode      ItemName       Total
----------------------------------
A              name1          5
A              name1          5
A              name2          10
B              name1          10 
B              name2          25
B              name1          30
C              name2          5
C              name1          30
C              name1          20

我想显示 itemcode A 和 B 在 Total

列中不具有相同值的所有内容

我的预期结果

ItemCode          ItemName         Total
----------------------------------------
A                  name1             5
A                  name1             5
B                  name2             25
B                  name1             30

我已经问过这个问题了，但是这次我的问题比我上次的问题清楚多了。我认为 1 个解决方案是自连接，但我无法弄清楚。任何帮助对我来说意义重大，谢谢！

Answer 1

试试这个查询：

select i.*
from my_table i
where i.ItemCode in ('A','B')
and (select count(*) from my_table t where t.ItemCode in ('A','B') 
and t.ItemCode != i.ItemCode and t.total = i.total) = 0

Answer 2

假设您需要的行不存在具有相同 Total 的不同 itemCode 的另一行，并假设 ItemCode 始终不为空，一个简单的解决方案可以是这样的：

with test(ItemCode, ItemName, Total) as 
(
    select 'A', 'name1', 5  from dual union all
    select 'A', 'name1', 5  from dual union all
    select 'A', 'name2', 10 from dual union all
    select 'B', 'name1', 10 from dual union all
    select 'B', 'name2', 25 from dual union all
    select 'B', 'name1', 30 from dual union all
    select 'C', 'name2', 5  from dual union all
    select 'C', 'name1', 30 from dual union all
    select 'C', 'name1', 20 from dual
)
select *
from test t1
where ItemCode in ('A', 'B')
  and not exists (
                   select 1
                   from test t2
                   where t1.total    =  t2.total
                     and t1.itemCode != t2.itemCode
                     and ItemCode in ('A', 'B')
                 )

以下速度更快，但可读性较差：

select ItemCode, ItemName, Total
from (
        select ItemCode, ItemName, Total, count(distinct ItemCode) over (partition by Total) as itemCount
        from test
        where ItemCode in ('A', 'B')
     )
where itemCount = 1

Answer 3

SELECT A.* FROM (SELECT * FROM MYTABLE WHERE ITEMCODE='A')A
       LEFT JOIN (SELECT * FROM MYTABLE WHERE ITEMCODE='B')B ON
    A.TOTAL=B.TOTAL
WHERE B.ITEMCODE IS NULL

UNION

SELECT B.* FROM (SELECT * FROM MYTABLE WHERE ITEMCODE='B')B
       LEFT JOIN (SELECT * FROM MYTABLE WHERE ITEMCODE='A')A ON
    B.TOTAL=A.TOTAL
WHERE A.ITEMCODE IS NULL

查询在另一列中没有相同值的列

query a column that does not have the same value in another column

sql

oracle

join

self-join

oracle11g