查找行只出現在兩個查詢之一的結果

Question

我有兩個JOIN查詢，它們的輸出列爲Id。如何查找由查詢1返回但未由查詢2返回的所有Id值？

select Id from Table1 join Table2; 

select Id from Table2 join Table3; 

Answer 1

SELECT id FROM dbo.Table1 INNER JOIN dbo.Table2 ON ... 
EXCEPT 
SELECT id FROM dbo.Table2 INNER JOIN dbo.Table3 ON ...; 

Answer 2

試試這個：

select Id from Table1 join Table2 
union 
select Id from Table2 join Table3