连接4个表来计算它们的值

Question

我有 4 个表需要连接，其中 3 个需要计算，它们的值在第四个表中提供。在连接中，有 2 个字段很重要，需要进行分组。

第一张表：

SELECT  customerId, baseCurrencyId, totalOldDebt, totalRecoveredDebt, totalPaidDebt
FROM    ViewCustomerDebt

第一次查询的结果：

客户ID	基础货币ID	旧债总额	已收回债务总额	已偿债务总额
2	1	2000	950	0
4	1	0	10	0
1	2	100	100	0
2	2	300	500	1000

第二张表：

SELECT  customerId ,paymentTypeId ,baseCurrencyId ,subTotalPrice ,totalPrice ,totalCost
FROM    ViewCustomerSell

第二次查询的结果：

客户ID	付款类型Id	基础货币ID	小计价格	总价	总成本
1	1	1	5300	5300	5008
2	1	1	292.5	287.5	181
2	2	1	20638.5	20538.5	492
2	2	2	10	10	1000
3	1	1	174.5	174.5	160.5
3	2	1	1172	1172	6016
4	1	1	661	661	626
4	2	1	144	144	132.25

第三个查询：

SELECT  customerId ,paymentTypeId ,baseCurrencyId ,totalPrice ,totalCost
FROM    ViewCustomerPurchase

第三次查询的结果：

客户ID	付款类型Id	基础货币ID	总价	总成本
2	2	1	91610	0
3	2	1	115.5	0

paymentTypeId

和

ViewCustomerSell

中的

ViewCustomerDebt

是

1

或

2

。 然后我想从

Customer

表中进行选择并获取这些列：

customerId
baseCurrencyId,
totalPaidSellPrice (ViewCustomerSell.totalPrice where paymentTypeId = 1),
totalDebtSellPrice (ViewCustomerSell.totalPrice where paymentTypeId = 2),
totalSellDebt ((ViewCustomerSell.totalPrice where paymentTypeId = 2) + ViewCustomerDebt.totalOldDebt - ViewCustomerDebt.totalRecoveredDebt),
totalPaidPurchasePrice (ViewCustomerPurchase.totalPrice where paymentTypeId = 1),
totalDebtPurchasePrice (ViewCustomerPurchase.totalPrice where paymentTypeId = 2),
totalPurchaseDebt ((ViewCustomerPurchase.totalPrice where paymentTypeId = 2) - ViewCustomerDebt.totalPaidDebt),
totalDebtExchange (totalSellDebt - totalPurchaseDebt)

但我希望它们全部按

customerId

和

baseCurrencyId

分组。

这是我的预期结果：

客户ID	基础货币ID	总付费销售价格	总债务出售价格	总销售债务	总付费购买价格	总债务购买价格	购买债务总额	总债务交换
2	1	287.5	20538.5	21588.5	0	91610	91610	-70021.5
4	1	661	144	134	0	0	0	134
1	2	0	0	0	0	0	0	0
2	2	0	10	-190	0	0	-1000	-1190
3	1	174.5	1172	1172	0	115.5	115.5	1056.5
1	1	5300	0	0	0	0	0	0

等等。

我尝试了这段代码，但它没有按我想要的方式工作：

SELECT C.id as customerId,
    COALESCE (VCD.baseCurrencyId, VCSP.baseCurrencyId, VCSD.baseCurrencyId, VCPP.baseCurrencyId, VCPD.baseCurrencyId) 
        AS baseCurrencyId,
    VCSP.totalPrice as totalPaidSellPrice,
    VCSD.totalPrice as totalDebtSellPrice,
    VCSD.totalPrice + VCD.totalOldDebt - VCD.totalRecoveredDebt as totalSellDebt,
    VCPP.totalPrice as totalPaidPurchasePrice,
    VCPD.totalPrice as totalDebtPurchasePrice,
    VCPD.totalPrice - VCD.totalPaidDebt as totalPurchaseDebt,
    (VCSD.totalPrice + VCD.totalOldDebt - VCD.totalRecoveredDebt) -
        (VCPD.totalPrice - VCD.totalPaidDebt) as totalExchange
from ViewCustomerDebt as VCD
Full outer join ViewCustomerSell as VCSP on VCD.customerId = VCSP.customerId and 
    VCD.baseCurrencyId = VCSP.baseCurrencyId and VCSP.paymentTypeId = 1
Full outer join ViewCustomerSell as VCSD on VCD.customerId = VCSD.customerId 
    and VCD.baseCurrencyId = VCSD.baseCurrencyId and VCSD.paymentTypeId = 2
Full outer join ViewCustomerPurchase as VCPP on VCD.customerId = VCPP.customerId and 
    VCD.baseCurrencyId = VCPP.baseCurrencyId and VCPP.paymentTypeId = 1
Full outer join ViewCustomerPurchase as VCPD on VCD.customerId = VCPD.customerId 
    and VCD.baseCurrencyId = VCPD.baseCurrencyId and VCPD.paymentTypeId = 2
INNER JOIN dbo.Customer AS C ON C.id = 
        COALESCE (VCD.customerId, VCSP.customerId, VCSD.customerId, VCPP.customerId, VCPD.customerId)

这是一个数据库小提琴：https://dbfiddle.uk/uGO8az0s

Answer 1

您想要每个 customerId 和 baseCurrencyId 一行的结果。因此，对于这两列上没有唯一约束的所有表，您必须首先聚合表，以便为每个 customerId 和 baseCurrencyId 生成一行。到达那里后，您可以将这两列的结果连接起来。在下面的查询中，我假设聚合对于您的所有视图都是必要的。

WITH
  debt AS
  (
    SELECT 
      customerid,
      basecurrencyid,
      SUM(totalolddebt) AS old,
      SUM(totalrecovereddebt) AS recovered,
      SUM(totalpaiddebt) AS paid
    FROM viewcustomerdebt
    GROUP BY customerid, basecurrencyid
  ),
  sell AS
  (
    SELECT
      customerid,
      basecurrencyid,
      SUM(CASE WHEN paymenttypeid = 1 THEN totalprice END) AS price_type1,
      SUM(CASE WHEN paymenttypeid = 2 THEN totalprice END) AS price_type2
    FROM viewcustomersell
    GROUP BY customerid, basecurrencyid
  ),
  purchase AS
  (
    SELECT
      customerid,
      basecurrencyid,
      SUM(CASE WHEN paymenttypeid = 1 THEN totalprice END) AS price_type1,
      SUM(CASE WHEN paymenttypeid = 2 THEN totalprice END) AS price_type2
    FROM viewcustomerpurchase
    GROUP BY customerid, basecurrencyid
  )
SELECT
  COALESCE(debt.customerid, sell.customerid, purchase.customerid) AS customerid,
  COALESCE(debt.basecurrencyid, sell.basecurrencyid, purchase.basecurrencyid) AS basecurrencyid,
  sell.price_type1 AS total_paid_sell_price,
  sell.price_type2 AS total_debt_sell_price,
  sell.price_type2 + debt.old - debt.recovered AS total_sell_debt,
  purchase.price_type1 AS total_paid_purchase_price,
  purchase.price_type2 AS total_debt_purchase_price,
  purchase.price_type2 - debt.paid AS total_purchase_debt,
  (sell.price_type2 + debt.old - debt.recovered) - (purchase.price_type2 - debt.paid) AS total_debt_exchange
FROM debt
FULL OUTER JOIN sell ON sell.customerid = debt.customerid
                    AND sell.basecurrencyid = debt.basecurrencyid
FULL OUTER JOIN purchase ON purchase.customerid = COALESCE(debt.customerid, sell.customerid)
                        AND purchase.basecurrencyid = COALESCE(debt.basecurrencyid, sell.basecurrencyid)
ORDER BY
  COALESCE(debt.customerid, sell.customerid, purchase.customerid),
  COALESCE(debt.basecurrencyid, sell.basecurrencyid, purchase.basecurrencyid);

如果 SQL Server 符合标准 SQL 并支持

USING

子句，则联接将如下所示：

FROM debt
FULL OUTER JOIN sell USING (customerid, basecurrencyid)
FULL OUTER JOIN sell ON USING (customerid, basecurrencyid)

和笨手笨脚的人

COALESCE(debt.customerid, sell.customerid, purchase.customerid)
COALESCE(debt.basecurrencyid, sell.basecurrencyid, purchase.basecurrencyid)

会变得单纯

customerid
basecurrencyid

演示：https://dbfiddle.uk/OIDGb6g9