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我不完全理解以下列出的查询结果：

CREATE TABLE #tmpAccountsTable (ID INT PRIMARY KEY, AccountID INT, 

AccountName varchar(20), CompanyID int, CompanyName varchar(50))
INSERT INTO #tmpAccountsTable (ID, AccountID, AccountName, CompanyID, CompanyName)
SELECT 1 AS ID, 1 AS AccountID, 'ABC Account' AS AccountName, 1 AS CompanyID, 'Stark Enterprise' AS CompanyName UNION
SELECT 2 AS ID, 1 AS AccountID, 'ABC Account' AS AccountName, 1 AS CompanyID, 'Stark Enterprise' AS CompanyName UNION
SELECT 3 AS ID, 2 AS AccountID, 'DEF Account' AS AccountName, 1 AS CompanyID, 'Stark Enterprise' AS CompanyName UNION
SELECT 4 AS ID, 3 AS AccountID, 'GHI Account' AS AccountName, 1 AS CompanyID, 'Stark Enterprise' AS CompanyName UNION
SELECT 5 AS ID, 4 AS AccountID, 'JKL Account' AS AccountName, 1 AS CompanyID, 'Stark Enterprise' AS CompanyName UNION
SELECT 6 AS ID, 1 AS AccountID, 'ABC Account' AS AccountName, 1 AS CompanyID, 'Stark Enterprise' AS CompanyName UNION
SELECT 7 AS ID, 1 AS AccountID, 'ABC Account' AS AccountName, 1 AS CompanyID, 'Stark Enterprise' AS CompanyName UNION
SELECT 8 AS ID, 1 AS AccountID, 'ABC Account' AS AccountName, 1 AS CompanyID, 'Stark Enterprise' AS CompanyName UNION
SELECT 9 AS ID, 2 AS AccountID, 'DEF Account' AS AccountName, 1 AS CompanyID, 'Stark Enterprise' AS CompanyName

SELECT DENSE_RANK() OVER (PARTITION BY AccountID ORDER BY CompanyName) as AccountRANK, * FROM #tmpAccountsTable

DROP TABLE #tmpAccountsTable

执行上述操作，我得到以下结果集：

结果集

根据我的理解，SELECT DENSE_RANK() OVER (PARTITION BY AccountID ORDER BY CompanyName) as AccountRANK, * FROM #tmpAccountsTable应该为所有相同的 AccountId 创建一个分区，并且它们应该收到相同的DENSE_RANK()值，但可以看出，情况并非如此。

我错过了什么？

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1 回答 1

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如果你想为每个单独的值AccountId，那么这应该是的一部分，而ORDER BY不是PARTITION BY：

SELECT DENSE_RANK() OVER (ORDER BY AccountID, CompanyName) as AccountRANK, *
FROM #tmpAccountsTable;

PARTITION BY用于重置计数器，因此每个都从AccountId1 开始。然后按CompanyNames顺序排列。因为它们都具有相同的值，所以结果是1。

于 2019-07-03T19:01:26.223 回答