Sql server 为什么'；这个工会不给我两个专栏吗？

我希望联接的输出中有两列。我只有一个，storeID。StoreComponentID不在那里

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如果需要两列，则需要声明两列

SELECT column1, NULL as column2 -- even when Table1 doesnt have column2
FROM Table1
UNION 
SELECT NULL as column1, column2 -- even when Table2 doesnt have column1
FROM Table2

现在如果你想并排合并

WITH idA as (
     SELECT StoreComponentID,
            ROW_NUMBER() OVER (ORDER BY StoreComponentID) as rn
     FROM StoreComponent
), idB as (
     SELECT StoreID
            ROW_NUMBER() OVER (ORDER BY StoreID) as rn
     FROM Store
)
SELECT idA.StoreComponentID, 
       idB.StoreID
FROM idA 
FULL JOIN idB
  ON idA.rn = idB.rn

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我想出了一个简单的解决办法：

select S.storeid as sID, SC.storecomponentid as SCID from tstore as S, tstorecomponent as SC

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您的期望输出是什么？两列并排？或者一个

列，空

，然后

空，列

？请阅读，这里是学习如何提高问题质量和获得更好答案的好地方。