Question

我试图比较两个＆＃34;列表＆＃34;在同一个表中获取记录，其中customerId列具有相同的值但storeid不同。

列表（表格定义）

name             listid   storeid   customerid

ComparingList1     1        10         100
ComparingList1     1        10         101
ComparingList1     1        11         100
ComparingList1     1        11         102
ComparingList1     1        11         103
ComparingList1     1        11         104

ComparingList2     2        10         100
ComparingList2     2        10         101
ComparingList2     2        11         100
ComparingList2     2        11         102
ComparingList2     2        11         103
ComparingList2     2        12         104
ComparingList2     2        12         105

查询

SELECT 
   ComparingList2.customerid as customerId,
   ComparingList1.storeid as expectedStoreId, 
   ComparingList2.storeid as actualStoreId
FROM Lists ComparingList2
LEFT JOIN Lists ComparingList1
   on ComparingList1.customerid = ComparingList2.customerid
WHERE 
   ComparingList1.listid = 1
   AND ComparingList2.listid = 2
   AND ComparingList2.storeid <> ComparingList1.storeid

这个查询给了我：

customerid   expectedStoreId   actualStoreId
   100             10                 11 
   100             11                 10 
   104             11                 12

但我想要的结果是：

customerid         expectedStoreId      actualStoreId
   104                   11                   12

Fiddle

Answer 1

嗯，你很亲密。我在你的where子句中添加了另一个条件，它给出了所需的结果，但是我不确定它将如何对实际数据执行。

以下是修改过的查询：

SELECT 
  ComparingList2.customerid as customerId,
  ComparingList1.storeid as expectedStoreId, 
  ComparingList2.storeid as actualStoreId
FROM Lists ComparingList2
LEFT JOIN Lists ComparingList1
  on ComparingList1.customerid = ComparingList2.customerid 
WHERE ComparingList1.listid = 1
AND ComparingList2.listid = 2
AND ComparingList2.storeid <> ComparingList1.storeid
AND NOT EXISTS -- Added this part
(
    SELECT 1 
    FROM Lists c
    WHERE ComparingList1.customerid = c.customerid
    AND ComparingList1.storeid = c.storeid
    AND c.listid = 2
)

Answer 2

通过删除匹配项，您可以加入customerid上的其余值，如下所示：

;WITH list1 as
(
  SELECT storeid, customerid 
  FROM Lists
  WHERE listid = 1
  EXCEPT 
  SELECT storeid, customerid
  FROM Lists
  WHERE listid = 2
), list2 as
(
  SELECT storeid, customerid 
  FROM Lists
  WHERE listid = 2
  EXCEPT 
  SELECT storeid, customerid 
  FROM Lists
  WHERE listid = 1
)
SELECT 
  list1.customerid, 
  list1.storeid ExpectedStoreId,
  list2.storeid ActualStoreId
FROM list1 
JOIN list2 
ON list1.customerid= list2.customerid

获取一列相同但另一列不同的记录

2 个答案: