SQL Server差异（与交叉相反）

Question

在SQL Server中寻找简单/可扩展的方法来设置“差异”，请参阅下文。

如果你无法从图片中看出我正在寻找那些不在交叉路口的东西。

我已经看到了一种方法：

select * from (      
    (select 'test1' as a, 1 as b)
 union all
  (select 'test2' as a , 2 as b union all select 'test1' as a , 1 as b )
)un group by a,b  having count(1)=1

但是我担心如果我使用两个大集合会发生什么（我不会从select''常量语句查询，我的查询将从真实表中提取。）

编辑：

可能的解决方案......

drop table #temp_a;
drop table #temp_b;

 go


  select * into #temp_a from (
   select 1 as num, 'String' as two, 'int'as three, 'purple' as four union all
   select 2 as num, 'dog' as two, 'int'as three, 'purple' as four union all
   select 3 as num, 'dog' as two, 'int'as three, 'cat' as four ) a 

select * into #temp_b from (
  select 1 as num, 'String' as two, 'decimal'as three, 'purple' as four union all
  select 2 as num, 'dog' as two, 'int'as three, 'purple' as four union all
  select 3 as num, 'dog' as two, 'int'as three, 'dog' as four ) b 





   SELECT IsNull(a.num, b.num) A,IsNull(a.two, b.two) B, IsNull(a.three, b.three) C,                  
      IsNull(a.four, b.four) D 
     FROM #temp_a a 
   FULL OUTER JOIN #temp_b b ON (a.num=b.num AND a.two=b.two and a.three=b.three and a.four=b.four)
    WHERE   (a.num is null or b.num is null  )

结果：

  

1 String int purple

     

3只狗猫

     

1 String dec purple

     

3只狗狗

Answer 1

这样的事情怎么样？

SELECT A, B FROM Table1 EXCEPT SELECT A,B FROM Table2
UNION
SELECT A, B FROM Table2 EXCEPT SELECT A,B FROM Table1

以下是FULL OUTER JOIN方法的示例（假设A在两个表中都不可为空）

SELECT IsNull(Table1.A, Table2.A) a,IsNull(Table1.B, Table2.B) B
FROM Table1 
FULL OUTER JOIN Table2 ON (Table1.A=Table2.A AND Table1.B=Table2.B)
WHERE Table1.A is null or Table2.A is null

Answer 2

替代：

SELECT A, B FROM Table1 UNION SELECT A,B FROM Table2
EXCEPT
SELECT A, B FROM Table2 INTERSECT SELECT A,B FROM Table1

Answer 3

您所追求的是Full Outer Join, which SQL Server supports。