Question

我在选择以下代码中每行的顶部时遇到一些问题：

这将基于LineNoID，即行。

SELECT TOP 10

        DTM.[LineNoID]          as [Line ID],
        DTM.[Fault Code]        AS [DTM Fault Code],
        DTFC.[Fault Code]       AS [DTFC Fault Code], 
        COUNT(DTM.[Fault Code]) AS [Fault Code Occurences], 
        DTFC.[Fault Name],
        SUM(DTM.[Minutes Down]) AS [Total Minutes Down]

FROM

        DTMain          AS DTM,
        DTFaultCodes    AS DTFC,
        DTLine          AS DTL

WHERE   

        DTM.[Fault Code] = DTFC.[Fault Code]

AND     

        DTM.LineNoID = DTL.[LineNoID]

AND

        DTFC.[Category] = 'E'

GROUP BY 
            DTM.[LineNoID],
            DTM.[Fault Code],
            DTFC.[Fault Code],
            DTFC.[Fault Name]           

ORDER BY [Total Minutes Down] DESC

我查看了其他几篇帖子，并且正在努力将它们“转换”为我的代码。任何帮助将不胜感激！

谢谢，大卫

更新了查询：

SELECT
        [Line ID],
        [DTM Fault Code],
        [DTFC Fault Code],
        [Fault Code Occurences],
        [Total Minutes Down]
FROM
  (
SELECT
        ROW_NUMBER() OVER (PARTITION BY DTM.[LineNoID] ORDER BY SUM([Minutes Down] AS [Total Minutes Down]) DESC) [Line ID],
        DTM.[LineNoID]          AS [Line ID],
        DTM.[Fault Code]        AS [DTM Fault Code],
        DTFC.[Fault Code]       AS [DTFC Fault Code], 
        COUNT(DTM.[Fault Code]) AS [Fault Code Occurences], 
        DTFC.[Fault Name]
FROM
        DTMain          AS DTM,
        DTFaultCodes    AS DTFC,
        DTLine          AS DTL
WHERE
        DTM.[Fault Code] = DTFC.[Fault Code]
AND
        DTM.LineNoID = DTL.[LineNoID]
AND
        DTFC.[Category] = 'E'
GROUP BY
            DTM.[LineNoID],
            DTM.[Fault Code],
            DTFC.[Fault Code],
            DTFC.[Fault Name]
  ) s
WHERE [Total Minutes Down] <= 10

ORDER BY [Total Minutes Down] DESC

显示“'SUM'不是公认的内置函数名。”在运行上面的时候。

抱怨缺乏知识！

Answer 1

以下是基于我自己的数据库中的日志记录表的示例（SQL 2012）：

SELECT 
    IdentifyingValue,
    GroupingValue,
    RowNum,
    SummedValue
FROM 
  (
    SELECT  
        TrgTabName AS IdentifyingValue, 
        CAST(JobDate AS DATE) GroupingValue, 
        ROW_NUMBER() OVER (PARTITION BY TrgTabName ORDER BY SUM(TrgTabNewRows) DESC) RowNum,
        SUM(TrgTabNewRows) SummedValue
    FROM DWA_JobTableCount
    GROUP BY TrgTabName, CAST(JobDate AS DATE)
  ) s
WHERE RowNum <= 3

您可以使用基础SELECT语句替换示例s子查询，并修改ROW_NUMBER()函数以将LineNoID用作PARTITION BY和您的[Total Minutes Down]为ORDER BY DESC。然后修改外部查询以检索所需的列，并修改外部WHERE子句以获取所需的RowNum计数。

=============================================== ===================================

修改你很好地尝试了合并代码，但是有一些错误。其中一个是我的：我没有注意到你在原始查询中使用了SUM()函数，我告诉你在ROW_NUMBER()函数中使用该字段。在ROW_NUMBER()这样的窗口函数中使用任何类型的聚合是不允许的，所以必须发生的是三层查询，而不是我向您展示的两级查询：最低层是您的原始层（包括SUM），中间层将ROW_NUMBER()和排名添加到输出，外部添加基于ROW_NUMBER()的过滤器。

此处还有其他一些问题：您在错误定位的SUM()函数中包含别名，这可能是您收到的特定错误的原因。您还有两个名为Line ID的列，即使您尝试将其包含在Total Minutes Down中，也永远不会生成一个单独的列，为您提供SELECT的总和。 WHERE条款。最后，您的过滤器实际上仍未指向ROW_NUMBER()函数生成的列，这会伤害您。

步骤1：将分组和聚合放在嵌套查询中，将SUM添加为单独的列。当我在这里的时候，我还给你写了一些JOIN表达式的更新语法：使用这种格式，因为不再推荐使用逗号JOIN（正如marc_s在注释中指出的那样）。

第2步：添加ROW_NUMBER()函数以生成新列。这会使用列（Line ID和Total Minutes Down）生成一个名为RowNum的新列。

第3步：检索您想要的字段并过滤＆＃34; top＆＃34;十（RowNum字段有助于识别）。

请查看以下代码，并告诉我它是否适合您。我无法访问您的基表，因此我可能会错误地命名某个字段或引用错误的别名 - 由您来审核我的代码示例以确保它适合您的数据库。我相信这会产生您正在寻找的功能。

SELECT -- returns the data you wanted originally [Line ID], [DTM Fault Code], [DTFC Fault Code], [Fault Code Occurrences], [Fault Name], [Total Minutes Down] FROM ( SELECT -- adds the row number [Line ID], [DTM Fault Code], [DTFC Fault Code], [Fault Code Occurrences], [Fault Name], [Total Minutes Down], ROW_NUMBER() OVER (PARTITION BY [Line ID] ORDER BY [Total Minutes Down] DESC) RowNum -- numbers, in descending order, the rows for each Line ID FROM ( SELECT -- retrieves the base (aggregated) data used by the query DTM.[LineNoID] as [Line ID], DTM.[Fault Code] AS [DTM Fault Code], DTFC.[Fault Code] AS [DTFC Fault Code], COUNT(DTM.[Fault Code]) AS [Fault Code Occurrences], DTFC.[Fault Name], SUM(DTM.[Minutes Down]) AS [Total Minutes Down] -- you still need this column to use in your output and RowNum FROM DTMain DTM INNER JOIN -- note the new syntax DTFaultCodes DTFC ON DTM.[Fault Code] = DTFC.[Fault Code] -- this specifies what the relationship between the two tables is: please confirm this is correct. INNER JOIN DTLine DTL ON DTM.LineNoID = DTL.LineNoID WHERE DTFC.Category = 'E' -- this doesn't really need to be in the JOIN condition: because you are using INNER JOIN, it does the same thing in the WHERE clause. GROUP BY DTM.[LineNoID], DTM.[Fault Code], DTFC.[Fault Code], DTFC.[Fault Name] ) s1 -- the subquery at the first (lowest) level: think of it as a table with the data returned by the SELECT statement ) s2 -- the subquery at the second (middle) level WHERE RowNum <= 10 -- the filter that controls the 'TOP n'

SQL为每行选择TOP 10

1 个答案: