sql - 子查询在 MS SQL 中返回超过 1 个值

Question

在 MS Sql 中。

SELECT a.SellerID, 
       SUM(TransactionFee) as TransactionFees,
SUM(Quantity*a.PriceItem) as TransactionValue,
COUNT(*) as OrdersWithTransactionFees, 
            SUM(Quantity) as Qty,
            (SELECT SUM(a.Quantity*a.PriceItem) as WholeMonthTransactionValue 
            from BuyProductDetails where SellerID = a.SellerID) as aa
FROM BuyProductDetails as a
WHERE MONTH(a.OrderDate)=3
AND YEAR(a.OrderDate)=2013
AND TransactionFee IS NOT NULL
GROUP BY a.SellerID

我有上面的查询......它似乎无法运行。

基本上，我有这张表BuyProductDetails存储来自不同卖家的所有订单。

有些订单会有 TransactionFee。

现在，我需要计算这些带有 TransactionFee 的订单的总销售额，以及这些卖家的总销售额，包括那些没有 TransactionFee 的订单。

结果集应具有以下字段：

1. 卖家ID
2. 交易费用总额
3. 总销售额
4. 有交易费的订单数量
5. 订购数量
6. 该卖家的总销售额

但是当我运行这个 sql 时，它返回以下错误：

Subquery returned more than 1 value. This is not permitted when the subquery follows =, !=, <, <= , >, >= or when the subquery is used as an expression.

任何帮助深表感谢。谢谢你。

Answer 1

尝试过这样的事情吗？

 SELECT a.SellerID, 
    SUM(TransactionFee) as TransactionFees,
    SUM(Quantity*a.PriceItem) as TransactionValue,
    COUNT(*) as OrdersWithTransactionFees, 
    SUM(Quantity) as Qty,
    MIN(a.WholeMonthTransactionValue) as WholeMonthTransactionValue
  FROM BuyProductDetails as a,
(SELECT b.SellerID, 
        SUM(b.Quantity*b.PriceItem) as WholeMonthTransactionValue,
        MONTH(b.OrderDate),
        YEAR(b.OrderDate)
 FROM BuyProductDetails b 
 GROUP BY b.SellerID,
    MONTH(b.OrderDate) as MonthID,
    YEAR(b.OrderDate) as YearID) as aa
    WHERE MONTH(a.OrderDate)=3
      AND YEAR(a.OrderDate)=2013
      AND TransactionFee IS NOT NULL
      AND a.SellerID = aa.SellerID
      AND MONTH(a.OrderDate)=aa.MonthID
      AND YEAR(a.OrderDate) = aa.YearID
    GROUP BY a.SellerID)

Answer 2

您可以在CASE表达式中使用更有效的选项

SELECT a.SellerID, 
       SUM(CASE WHEN TransactionFee IS NOT NULL THEN TransactionFee END) AS TransactionFees,
       SUM(CASE WHEN TransactionFee IS NOT NULL THEN Quantity * PriceItem END) AS TransactionValue,
       COUNT(CASE WHEN TransactionFee IS NOT NULL THEN 1 END) as OrdersWithTransactionFees, 
       SUM(CASE WHEN TransactionFee IS NOT NULL THEN Quantity END) as Qty,
       SUM(Quantity * PriceItem) AS WholeMonthTransactionValue         
FROM BuyProductDetails AS a
WHERE MONTH(a.OrderDate) = 3 AND YEAR(a.OrderDate) = 2013
GROUP BY a.SellerID

SQLFiddle上的演示

或者只是在子查询中添加正确的别名

SELECT a.SellerID, 
       SUM(TransactionFee) as TransactionFees,
       SUM(Quantity*a.PriceItem) as TransactionValue,
       COUNT(*) as OrdersWithTransactionFees, 
       SUM(Quantity) as Qty,
       (SELECT SUM(d.Quantity * d.PriceItem)
        FROM BuyProductDetails d
        WHERE d.SellerID = a.SellerID) as WholeMonthTransactionValue 
FROM BuyProductDetails as a
WHERE MONTH(a.OrderDate)=3
AND YEAR(a.OrderDate)=2013
AND TransactionFee IS NOT NULL
GROUP BY a.SellerID

SQLFiddle上的演示