(原創，到現在為至最為復雜的SQL查詢代碼）實現按部門月卡余額總額分組統計的SQL查詢代碼（在Ms SQL Serve…

SELECT dp.dpname1 AS 部門, cust_dp_SumOddfre.sum_oddfare AS 當月卡總余額
FROM (SELECT T_Department.DpCode1, SUM(custid_SumOddfare_group.sum_oddfare)
              AS sum_oddfare
        FROM (SELECT l2.CustomerID, SUM(r1.oddfare) AS sum_oddfare
                FROM (SELECT CustomerID, MAX(OpCount) AS max_opcount
                        FROM (SELECT CustomerID, OpCount, RTRIM(CAST(YEAR(OpDt)
                                      AS char)) + '-' + RTRIM(CAST(MONTH(OpDt) AS char))
                                      + '-' + RTRIM(DAY(0)) AS dt
                                FROM T_ConsumeRec
                                UNION
                                SELECT CustomerID, OpCount, RTRIM(CAST(YEAR(cashDt)
                                      AS char)) + '-' + RTRIM(CAST(MONTH(cashDt) AS char))
                                      + '-' + RTRIM(DAY(0)) AS dt
                                FROM T_Cashrec) l1
                        WHERE (dt <= '2005-6-1')/*輸入查詢月份,可用參數傳遞*/
                        GROUP BY CustomerID) l2 INNER JOIN
                          (SELECT CustomerID, OpCount, oddfare
                         FROM T_ConsumeRec
                         UNION
                         SELECT CustomerID, OpCount, oddfare
                         FROM T_Cashrec) r1 ON l2.CustomerID = r1.CustomerID AND
                      r1.OpCount = l2.max_opcount
                GROUP BY l2.CustomerID) custid_SumOddfare_group INNER JOIN
              T_Customers ON
              custid_SumOddfare_group.CustomerID = T_Customers.CustomerID INNER JOIN
              T_Department ON SUBSTRING(T_Customers.Aclearcase/" target="_blank" >ccount, 1, 2)
              = T_Department.DpCode1 AND SUBSTRING(T_Customers.Account, 3, 2)
              = T_Department.DpCode2 AND SUBSTRING(T_Customers.Account, 5, 3)
              = T_Department.DpCode3
        GROUP BY DpCode1) cust_dp_SumOddfre INNER JOIN
          (SELECT DISTINCT dpcode1, dpname1
         FROM t_department) dp ON dp.dpcode1 = cust_dp_SumOddfre.DpCode1

附：查詢用到的基本表形成腳本：

CREATE TABLE [dbo].[T_CashRec] ( --出納明細賬本
 [StatID] [tinyint] NOT NULL ,
 [CashID] [smallint] NOT NULL ,
 [Port] [tinyint] NOT NULL ,
 [Term] [tinyint] NOT NULL ,
 [CashDt] [datetime] NOT NULL ,--存取款時間
 [CollectDt] [datetime] NOT NULL ,
 [CustomerID] [int] NOT NULL ,
 [OpCount] [int] NOT NULL ,--某卡的操作次數，只累加
 [InFare] [money] NOT NULL ,
 [OutFare] [money] NOT NULL ,
 [SumFare] [money] NOT NULL ,
 [OddFare] [money] NOT NULL ,--此次操作后該卡的余額
 [MngFare] [money] NOT NULL ,
 [Hz] [tinyint] NOT NULL ,
 [CurSum] [smallmoney] NULL ,
 [CurCount] [smallint] NULL ,
 [CardSN] [tinyint] NULL
) ON [PRIMARY]
GO

CREATE TABLE [dbo].[T_ConsumeRec] ( --消費明細賬本
 [StatID] [tinyint] NOT NULL ,
 [Port] [tinyint] NOT NULL ,
 [Term] [tinyint] NOT NULL ,
 [CustomerID] [int] NOT NULL ,
 [OpCount] [int] NOT NULL , --某卡的操作次數，只累加
 [OpDt] [datetime] NOT NULL ,--消費時間
 [CollectDt] [datetime] NOT NULL ,
 [MealID] [tinyint] NOT NULL ,
 [SumFare] [smallmoney] NOT NULL ,
 [OddFare] [smallmoney] NOT NULL ,--此次操作后該卡的余額
 [MngFare] [smallmoney] NOT NULL ,
 [OpFare] [smallmoney] NOT NULL ,
 [Hz] [tinyint] NOT NULL ,
 [MenuID] [smallint] NULL ,
 [MenuNum] [tinyint] NULL ,
 [OddFarePre] [smallmoney] NULL ,
 [RecNo] [smallint] NULL ,
 [CardSN] [tinyint] NOT NULL ,
 [CardVer] [tinyint] NULL
) ON [PRIMARY]
GO

CREATE TABLE [dbo].[T_Customers] ( --客戶賬本
 [CustomerID] [int] NOT NULL , --客戶號，主鍵
 [StatCode] [varchar] (3) COLLATE Chinese_PRC_CI_AS NOT NULL ,
 [Account] [varchar] (7) COLLATE Chinese_PRC_CI_AS NOT NULL ,--單位代號
 [Name] [varchar] (12) COLLATE Chinese_PRC_CI_AS NOT NULL ,
 [CardNo] [int] NOT NULL ,
 [CardSN] [tinyint] NULL ,
 [CardType] [tinyint] NOT NULL ,
 [Status] [tinyint] NOT NULL ,
 [OpenDt] [datetime] NOT NULL ,
 [CashID] [smallint] NOT NULL ,
 [SumFare] [smallmoney] NOT NULL ,
 [ConsumeFare] [smallmoney] NOT NULL ,
 [OddFare] [smallmoney] NOT NULL ,
 [OpCount] [int] NOT NULL ,
 [CurSubsidyFare] [smallmoney] NOT NULL ,
 [SubsidyDT] [datetime] NOT NULL ,
 [SubsidyOut] [char] (1) COLLATE Chinese_PRC_CI_AS NOT NULL ,
 [Alias] [varchar] (10) COLLATE Chinese_PRC_CI_AS NULL ,
 [outid] [varchar] (20) COLLATE Chinese_PRC_CI_AS NULL ,
 [UpdateID] [tinyint] NOT NULL ,
 [Pwd] [char] (4) COLLATE Chinese_PRC_CI_AS NULL ,
 [QuChargFare] [smallmoney] NULL ,
 [HasTaken] [tinyint] NULL ,
 [DragonCardNo] [char] (19) COLLATE Chinese_PRC_CI_AS NULL ,
 [ApplyCharg] [smallmoney] NULL ,
 [ChargPer] [smallmoney] NULL ,
 [MingZu] [varchar] (20) COLLATE Chinese_PRC_CI_AS NULL ,
 [Sex] [char] (2) COLLATE Chinese_PRC_CI_AS NULL ,
 [Memo] [varchar] (100) COLLATE Chinese_PRC_CI_AS NULL ,
 [WeiPeiDW] [varchar] (10) COLLATE Chinese_PRC_CI_AS NULL ,
 [CardConsumeType] [tinyint] NULL ,
 [LeaveSchoolDT] [datetime] NULL ,
 [UseValidDT] [tinyint] NOT NULL ,
 [NoUseDate] [datetime] NOT NULL
) ON [PRIMARY]
GO

CREATE TABLE [dbo].[T_Department] ( --單位帳本,三級單位制,樹型結構
 [DpCode1] [char] (2) COLLATE Chinese_PRC_CI_AS NOT NULL ,
 [DpCode2] [char] (2) COLLATE Chinese_PRC_CI_AS NULL ,
 [DpCode3] [char] (3) COLLATE Chinese_PRC_CI_AS NULL ,
 [DpName1] [varchar] (30) COLLATE Chinese_PRC_CI_AS NULL ,
 [DpName2] [varchar] (30) COLLATE Chinese_PRC_CI_AS NULL ,
 [DpName3] [varchar] (30) COLLATE Chinese_PRC_CI_AS NULL ,
 [N_SR] [int] NOT NULL ,
 [BatNum] [smallint] NULL
) ON [PRIMARY]
GO