如何显示此输出？答案

【问题标题】：How to show this outuput?如何显示此输出？
【发布时间】：2016-10-21 10:14:00
【问题描述】：

我的查询是

SELECT 
    CustBillPayment.CustomerId, CustBillPayment.Customer_Name, 
    CustBillPayment.CustBill_Total, CustBillPayment.CustBill_Paid,
    CustBillPayment.CustBill_ReamingAmt, CustBillPayment.Created_Date, 
    CustBillPayment.Delivery_Date, CustBillPayment.Updated_Date, 
    Shirt_Mes.Shirt_Type, Shirt_Mes.Shirt_Qty, Shirt_Mes.Shirt_Price, 
    Shirt_Mes.Shirt_Total, 
    Pant_Mes.Pant_Type, Pant_Mes.Pant_QTY, Pant_Mes.Pant_Total, 
    Pant_Mes.Pant_Price
FROM 
    ((CustBillPayment 
INNER JOIN
    Shirt_Mes ON CustBillPayment.CustomerId = Shirt_Mes.CustomerId) 
INNER JOIN
    Pant_Mes ON CustBillPayment.CustomerId = Pant_Mes.CustomerId) 
WHERE 
    CustBillPayment.CustomerId = 17

输出是这样的并显示重复的行：

CustomerId CustNm  SType   SQty SPrice  STotal PType    PQTY    PTotal  PPrice
-------------------------------------------------------------------------------
17         lakhan  sType1   2    200     400   PType3   3         900     300
17         lakhan  sType1   2    200     400   PType4   1         400     400
17         lakhan  sType2   1    250     250   PType3   3         900     300
17         lakhan  sType2   1    250     250   PType4   1         400     400

但我想要

CustomerId CustNm  SType   SQty SPrice  STotal PType    PQTY    PTotal  PPrice
-------------------------------------------------------------------------------
17         lakhan  sType1   2    200     400   PType3   3         900     300
17         lakhan  sType2   1    250     250   PType4   1         400     400

【问题讨论】：

添加一个选择并按您想要的字段分组：select [yourfileds] from (your original query) group by [yourfields]
您是否尝试将Select Distinct 和Group By 添加到此查询？ SType 列似乎是分组的好列

标签： c# sql ms-access

【解决方案1】：

您不能SELECT DISTINCT，但其他人可能会觉得它有帮助。 edit 为您提供答案。

关键字DISTINCT 列出唯一行。要了解更多信息，请阅读：http://www.w3schools.com/sql/sql_distinct.asp。

编辑：

现在我看到了问题，我没有注意到之前的数字不适合。在这种情况下，关键字 DISTINCT 将无济于事。 JOIN 先加入Shirt_Mes 表，但是有两条记录，这意味着它会产生两行。接下来JOIN 加入表Pant_Mes 并且条件也从该表中选择两条记录。前面的每一行都针对这两条记录进行了扩展。在这种情况下，它会产生 2 x 2 行。

我猜，这是糟糕的表架构。您可以执行两个查询并在应用程序逻辑中组合结果：

SELECT
  CustBillPayment.CustomerId,
  CustBillPayment.Customer_Name,
  CustBillPayment.CustBill_Total,
  CustBillPayment.CustBill_Paid,
  CustBillPayment.CustBill_ReamingAmt,
  CustBillPayment.Created_Date,
  CustBillPayment.Delivery_Date,
  CustBillPayment.Updated_Date,
  Shirt_Mes.Shirt_Type,
  Shirt_Mes.Shirt_Qty,
  Shirt_Mes.Shirt_Price,
  Shirt_Mes.Shirt_Total
FROM
  CustBillPayment
  JOIN Shirt_Mes ON CustBillPayment.CustomerId = Shirt_Mes.CustomerId
WHERE
  CustBillPayment.CustomerId=17

和

SELECT
  CustBillPayment.CustomerId,
  CustBillPayment.Customer_Name,
  CustBillPayment.CustBill_Total,
  CustBillPayment.CustBill_Paid,
  CustBillPayment.CustBill_ReamingAmt,
  CustBillPayment.Created_Date,
  CustBillPayment.Delivery_Date,
  CustBillPayment.Updated_Date,
  Pant_Mes.Pant_Type,
  Pant_Mes.Pant_QTY,
  Pant_Mes.Pant_Total,
  Pant_Mes.Pant_Price
FROM
  CustBillPayment
  JOIN Pant_Mes ON CustBillPayment.CustomerId = Pant_Mes.CustomerId
WHERE
  CustBillPayment.CustomerId=17

或者您可以将所有商品放在一张桌子上（我猜它是用于电子商店或类似的东西）。更好的是更改表架构，但如果您有充分的理由将商品存储在单独的表中（并且商品类型不是很好的理由），您可以执行以下查询：

SELECT
  CustBillPayment.CustomerId,
  CustBillPayment.Customer_Name,
  CustBillPayment.CustBill_Total,
  CustBillPayment.CustBill_Paid,
  CustBillPayment.CustBill_ReamingAmt,
  CustBillPayment.Created_Date,
  CustBillPayment.Delivery_Date,
  CustBillPayment.Updated_Date,
  Goods_Mes.Type,
  Goods_Mes.Qty,
  Goods_Mes.Price,
  Goods_Mes.Total
FROM
  CustBillPayment
  JOIN (SELECT Shirt_Mes.Shirt_Type AS Type,
               Shirt_Mes.Shirt_Qty AS Qty,
               Shirt_Mes.Shirt_Price AS Price,
               Shirt_Mes.Shirt_Total AS Total,
               Shirt_Mes.CustomerId FROM Shirt_Mes
        UNION
        SELECT Pant_Mes.Pant_Type AS Type,
               Pant_Mes.Pant_Qty AS Qty,
               Pant_Mes.Pant_Price AS Price,
               Pant_Mes.Pant_Total AS Total,
               Pant_Mes.CustomerId FROM Pant_Mes
        ) Goods_Mes ON CustBillPayment.CustomerId = Goods_Mes.CustomerId
WHERE
  CustBillPayment.CustomerId=17

为了使查询更好，您可以删除Shirt_Total 和Pant_Total 并将Goods_Mes.Total 替换为Goods_Mes.Qty * Goods_Mes.Price。

【讨论】：

【解决方案2】：

应该可以的：

SELECT DISTINCT CustBillPayment.CustomerId,
            CustBillPayment.Customer_Name,
            CustBillPayment.CustBill_Total,
            CustBillPayment.CustBill_Paid,
            CustBillPayment.CustBill_ReamingAmt,
            CustBillPayment.Created_Date,
            CustBillPayment.Delivery_Date,
            CustBillPayment.Updated_Date,
            Shirt_Mes.Shirt_Type,
            Shirt_Mes.Shirt_Qty,
            Shirt_Mes.Shirt_Price,
            Shirt_Mes.Shirt_Total,
            Pant_Mes.Pant_Type,
            Pant_Mes.Pant_QTY,
            Pant_Mes.Pant_Total,
            Pant_Mes.Pant_Price
  FROM ((CustBillPayment INNER JOIN Shirt_Mes ON CustBillPayment.CustomerId = Shirt_Mes.CustomerId) INNER JOIN
        Pant_Mes ON CustBillPayment.CustomerId = Pant_Mes.CustomerId)
 WHERE CustBillPayment.CustomerId = 17
 GROUP BY Shirt_Mes.Shirt_Type

【讨论】：

请提出其他查询

【解决方案3】：

试试这个查询

SELECT CBP.CustomerId, CBP.Customer_Name, 
       CBP.CustBill_Total, CBP.CustBill_Paid, 
       CBP.CustBill_ReamingAmt, CBP.Created_Date, 
       CBP.Delivery_Date, CBP.Updated_Date, 
       SMES.Shirt_Type, SMES.Shirt_Qty, SMES.Shirt_Price, 
       SMES.Shirt_Total, PMES.Pant_Type, PMES.Pant_QTY,    
       PMES.Pant_Total, PMES.Pant_Price 
FROM   CustBillPayment AS CBP 
LEFT JOIN Shirt_Mes AS SMES ON CBP.CustomerId = SMES.CustomerId 
LEFT JOIN Pant_Mes AS PMES ON CBP.CustomerId = PMES.CustomerId 
WHERE CBP.CustomerId = 17

【讨论】：

【解决方案4】：

distinct 和 group by 仅在记录唯一的情况下才有效。

由于每行的 pant_type 不同，Distinct 仍将带回所有 4 行。 group by 也是如此。

您期望的最终输出是什么，因为顶部所需的输出对于 pant_type 没有意义？

【讨论】：

CustomerId CustNm SType SQty SPrice STotal PType PQTY PTotal PPrice -------------------------------- ----------------------------------------------------------- 17 lakhan sType1 2 200 400 PType3 3 900 300 17 lakhan sType2 1 250 250 PType4 1 400 400