如何在两列之间找到不同的元素（由两个子查询生成）？

Question

我的子查询产生如下结果：

coulmn1    column2
a          d
b          z1000
c          c
d
1
2
z1000      k

我想知道两组中的不同元素。 column1 = {a，b，c，1,2，d，z1000，.....}第2列= {d，c，z1000，k ......}我想要的结果是= {a， k，1,2，....}希望我说清楚..请让我知道我该怎么做..？

Answer 1

--Test Data
with temp_table as (
    select 'a' coulmn1,'b' column2 union all
    select 'b' coulmn1,'z1000' column2 union all
    select 'c' coulmn1,'c' column2 union all
    select 'd' coulmn1,'' column2 union all
    select 'z1000' coulmn1,'k' column2 
)

--use cross join and union to distinct data 
--you have to change temp_table to your own table
select * into #temp_table from  (
    select T.coulmn1,T2.column2 as column2  
    from temp_table T,temp_table T2
    where T.coulmn1 <> T2.column2
) T;
select coulmn1 from #temp_table
union
select column2 from #temp_table;

Test Link

Answer 2

一种方法是全外连接：

select coalesce(t1.col1, t2.col2)
from t t1 full join
     t t2
     on t1.col1 = t2.col2
where t1.col1 is null or t2.col2 is null;

另一种方法不需要运行子查询两次;

select v.col
from t cross apply
     (values (t.col1, 1), (t.col2, 2)) v(col, which)
group by v.col
having min(v.which) = max(v.which);

Answer 3

使用 EXCEPT 。

    SELECT column1
    FROM your_subquery
    EXCEPT
    SELECT column2
    FROM your_subquery
    UNION
    SELECT column2
    FROM your_subquery
    EXCEPT
    SELECT column1
    FROM your_subquery