测试一下你的T-SQL基础知识-subquery

一直以为自己SQL挺好的，没有想到今天在重构存储过程遇到了一个子查询的问题，修改为自连接之后发现居然结果不对,于是有了下面的测试。假设表中有如下数数据，请问Query1,Query2,Query3的查询结果？

ID	OrderID	TransID	Type
1	1	1	E
2	1	1	A
3	1	1	B
4	1	2	A
5	1	2	B
6	2	1	A
7	2	1	B
8	2	2	A

 

--Query 1

SELECT * FROM OrderDetail a

left join OrderDetail b ON a.OrderID=b.OrderID and a.TransID=b.TransID and b.Goods='E'

WHERE b.Goods is  null



--Query 2

SELECT * FROM OrderDetail a

WHERE a.TransID <>

(

   SELECT top 1 b.TransID FROM OrderDetail b WHERE b.OrderID=a.OrderID and b.Goods='E'

)



--Query 3

SELECT * FROM OrderDetail a

WHERE NOT EXISTS 

(

    SELECT  b.TransID,b.orderid  FROM OrderDetail b WHERE b.OrderID=a.OrderID and b.Goods='E'

)

在查看运行结果前请默默的写下您的答案：
Query1

ID    OrderID    TransID    Goods

4    1    2    A

5    1    2    B

6    2    1    A

7    2    1    B

8    2    2    A

View Code

Query2

ID    OrderID    TransID    Goods

4    1    2    A

5    1    2    B

View Code

Query3

ID    OrderID    TransID    Goods

6    2    1    A

7    2    1    B

8    2    2    A

View Code