Question

我试图基于另一个使用CTE的分区来增加列，到目前为止我有以下内容：

DECLARE @start      INT
DECLARE @end        INT
DECLARE @current    INT
DECLARE @contNum    INT

SET     @start      = (SELECT MAX(ContractIssueID) - 20 FROM Contract)
SET     @end        = (SELECT MAX(ContractIssueID) FROM Contract)
SET     @current    = (SELECT MIN(ContractIssueID) FROM Contract)
SET     @contNum    = 0

WHILE @current <= @end
BEGIN
    WITH CTE AS
    (
        SELECT ContractIssueID, JobID, ROW_NUMBER() OVER (PARTITION BY JobID ORDER BY JOBID DESC) AS RN
        FROM Contract
    )
    SELECT * FROM CTE
    WHERE ContractIssueID = @current
    SET @current = @current + 1
    CASE WHEN RN = 1 THEN SET @contNum = @contNum + 1 END
END

我在case语句中收到错误，当我尝试使用IF时，它不会将RN识别为列。

我有什么想法可以解决这个问题吗？

----编辑------------------------------------------

跑步时出错：

Msg 156, Level 15, State 1, Line 24
Incorrect syntax near the keyword 'CASE'.
Msg 102, Level 15, State 1, Line 25
Incorrect syntax near 'END'.

-----编辑-----------------------------------------

目的：我在这个表中有三列（ContractIssueNumber，JobID和ContractNumber）。 ContractNumber应该是一个静态值，其中JobID是相同的，而contractissuNumber是增量的，如下所示：

ContractIssueNumber -- JobID -- ContractNumber

1                       100     1
2                       100     1
3                       101     2
4                       102     3
5                       102     3

最初我只是将ContractNumber设置为jobID，但这似乎导致了问题，所以我试图根据JobId列的分区将它们设置为1,2,3等。

-----编辑-----------------------------------------

感谢所有帮助，最终和更优雅的解决方案在下面

WITH CTE AS
(
    SELECT ContractIssueID
        , JobID
        , ContractNumber
        , DENSE_RANK() OVER (ORDER BY JOBID ) AS RN
            FROM Contract
)
UPDATE CTE SET ContractNumber = RN

Answer 1

您的RN在套装声明中不可用。 RN仅在select中可用，因此您需要使用RN在select内增加@ContNum，然后设置@current

WITH CTE AS
    (
        SELECT ContractIssueID, JobID, ROW_NUMBER() OVER (PARTITION BY JobID ORDER BY JOBID DESC) AS RN
        FROM Contract
    )
    SELECT @contNum = @contNum + CASE WHEN RN = 1 THEN 1 END
    FROM CTE
    WHERE ContractIssueID = @current

    SET @current = @current + 1

我认为你也想要dense_rank而不是row_number：

    SELECT ContractIssueID
    , JobID
    , DENSE_RANK() OVER (ORDER BY JOBID DESC) AS RN
        FROM Contract
--        WHERE ContractIssueID = @current skip this when not using the loop

Answer 2

检查一下，

DECLARE @start      INT
DECLARE @end        INT
DECLARE @current    INT
DECLARE @contNum    INT

SELECT  @start=(MAX(ContractIssueID) - 20),@current=MIN(ContractIssueID) FROM Contract
SET     @end        = @start+20
SET     @contNum    = 0

WHILE @current <= @end
BEGIN
    WITH CTE AS
    (
        SELECT ContractIssueID, JobID, ROW_NUMBER() OVER (PARTITION BY JobID ORDER BY JOBID DESC) AS RN
        FROM Contract
    )
    SELECT @contNum = @contNum + CASE WHEN RN = 1 THEN 1 END
    FROM CTE
    WHERE ContractIssueID = @current
    SET @current = @current + 1

END

BTW，@ contNum的目的尚不清楚。首先是什么样的真实场景？你为什么要循环更新？这是主要问题。

Answer 3

试试这个，

SET @contNum=CASE WHEN RN = 1 then  = @contNum + 1 END

CASE或IF内部CTE声明

3 个答案: