sql-server - 查找仅出现在两个查询之一的结果中的行

Question

我有两个 JOIN 查询，它们给出的输出列是Id. 如何找到Id查询 1 返回但查询 2 未返回的所有值？

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

试试这个：

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