基于嵌套游标的更新

Question

这是针对 SSRS 报告的，所以我使用的是临时 tables。我有两个 table，一个用于交易，我只是用它来提取帐户和金额。第二个是摊销拖欠信息，我正在尝试根据交易进行调整，但我运行陷入语法问题。 case 语句是否不允许与游标或更新一起使用？

--Example Transaction:Account 123456 Principal 500.00 Interest 250.00

delinquent 5 months of 200 principal each month, the transaction had  principal amount of 500, the first two are left alone, the third is reduced to 100 to match the total to the transaction amount, leaving a remaining amount of 0

--Delinquent data
-- 11/2015 Prin 200 Int 80 -> Prin 0   Int 0 (running total  Prin 500 Int 250)
-- 10/2015 Prin 200 Int 80 -> Prin 0   Int 10 (running total  Prin 500 Int 250)
--  9/2015 Prin 200 Int 80 -> Prin 100 Int 80 (running total  Prin 500 Int 240)
--  8/2015 Prin 200 Int 80 -> Prin 200 Int 80 (running total  Prin 400 Int 160)
--  7/2015 Prin 200 Int 80 -> Prin 200 Int 80 (running total  Prin 200 Int 80) <- process starts from the oldest and goes up.

这需要使用游标，因为我无法在一个集合中处理，因为它必须从最旧的行开始，调整，找到剩余的总数，然后继续调整下一行。如果达到交易金额，则将剩余的行清零。然后我将剩余金额退还给交易 table。

Declare  TranCursor Cursor FORWARD_ONLY 
For Select LoanNumber, PrincipalCollected, InterestCollected, ServiceFee, PayoffPrincipal,PayoffInterest,PayoffServiceFee
From #transFinal 
FOR UPDATE OF PayoffPrincipal,PayoffInterest,PayoffServiceFee


Open TranCursor;
Fetch next from TranCursor into @TranLoan, @TranPrin, @TranInt, @TranServ, @POPrin,@POInt,@POServ
while (@@Fetch_status = 0) 
Begin
    --Process this individual loan's transaction by going through each set of amortized amounts starting with the oldest and reducing excess of transaction amounts to zero. 
    --eg. delinquent 3 months of 200 principal each month, the transaction had principal amount of 500, the first two are left alone, the third is reduced to 100 to match the total to the transaction amount
    --Transaction Principal 500 Interest 250
    --Delinquent data
    -- 11/2015 Prin 200 Int 80 -> Prin 0   Int 0 (running total  Prin 500 Int 250)
    -- 10/2015 Prin 200 Int 80 -> Prin 0   Int 10 (running total  Prin 500 Int 250)
    --  9/2015 Prin 200 Int 80 -> Prin 100 Int 80 (running total  Prin 500 Int 240)
    --  8/2015 Prin 200 Int 80 -> Prin 200 Int 80 (running total  Prin 400 Int 160)
    --  7/2015 Prin 200 Int 80 -> Prin 200 Int 80 (running total  Prin 200 Int 80) <- process starts from the oldest and goes up.
    Declare  DelqCursor  CURSOR FORWARD_ONLY 
    FOR select LoanNumber,DelqPrin ,DelqInt  ,DelqServFee from #dq 
        where LoanNumber = @TranLoan
        Order by PaidToDate Asc
        For update OF DelqPrin, DelqInt, DelqServFee;
        Open DelqCursor;
-----------------------------------------------------------------------------------------------------------
-- Processing individual row of delinquent data
-----------------------------------------------------------------------------------------------------------
Fetch next from DelqCursor into  @DelqPrin, @DelqInt, @DelqServ, @DelqPTD --, @POPrin,@POInt,@POServ
while (@@Fetch_status = 0) 
    BEGIN


            CASE when @TranPrin = 0 then set @DelqPrin = 0 -- Syntax error on case
                WHEN @TranPrin >0 and @TranPrin > @DelqPrin then -- Syntax error on when
                    set @TranPrin = @TranPrin - @DelqPrin
                    set @ColPrin = @ColPrin + @DelqPrin
                WHEN @TranPrin >0 and @TranPrin < @DelqPrin then 
                    set @ColPrin = @ColPrin + @TranPrin
                    set @TranPrin = 0 
                    set @DelqPrin = @DelqPrin -@TranPrin
            end

            CASE when @TranInt = 0 then set @DelqInt = 0
                WHEN @TranInt >0 and @TranInt > @DelqInt then 
                    set @TranInt = @TranInt - @DelqInt
                    set @ColInt = ColInt + @DelqInt
                WHEN  @TranInt >0 and @TranInt < @DelqInt then 
                    set @ColInt = @ColInt + @TranInt
                    set @TranInt = 0 
                    set @DelqInt = @DelqInt -@TranInt
            end

            CASE when @TranServ = 0 then set @DelqServFee = 0
                WHEN  @TranServ >0 and @TranServ> @DelqServ then 
                    set @TranServ = @TranServ - @DelqServ
                    set @ColServ = ColServ + @DelqServ
                WHEN  @TranServ >0 and @TranServ < @DelqServ then 
                    set @ColServ = @ColServ + @TranServ
                    set @TranServ = 0 
                    set @DelqServ = @DelqServ -@TranServ
            end

Fetch next from DelqCursor into  @DelqPrin, @DelqInt, @DelqServ, @DelqPTD 
End
-----------------------------------------------------------------------------------
--All rows of delinquent data for a single loan have been processed. Now we update the Payoff columns
----------------------------------------------------------------------------------
Set @PoPrin =  @ColPrin
Set @PoInt =  @ColInt
Set @PoServ =  @ColServ
--Todo Finish update statement for outside loop to update transaction table
Close DelqCursor-- Finished with delinquent data for this loan. We close the cursor
Fetch next from TranCursor into @TranLoan, @TranPrin, @TranInt, @TranServ, @POPrin,@POInt,@POServ --Start Processing next loan
End 

Close TranCursor
deallocate DelqCursor
deallocate TranCursor

我将不胜感激我能得到的任何见解，以弄清楚为什么我的 case when 语句给我错误。我在 msdn 语法中看不到任何会阻止案例逻辑工作的内容。

Answer 1

您编写 CASE 语句的方式将不起作用。案例逻辑需要在 SELECT 或 SET 内发生。你的 在外面 ，SET 在中间，在 THEN 之后。

对于代码中的每个 CASE，您都需要将逻辑更改为类似的内容。

IF @TranPrin = 0 
    SET @DelqPrin = 0 

IF @TranPrin >0 AND @TranPrin > @DelqPrin
BEGIN
    SET @TranPrin = @TranPrin - @DelqPrin
    SET @ColPrin = @ColPrin + @DelqPrin
END

IF @TranPrin > 0 AND @TranPrin < @DelqPrin
BEGIN
    SET @ColPrin = @ColPrin + @TranPrin
    SET @TranPrin = 0 
    SET @DelqPrin = @DelqPrin -@TranPrin
END

CASE (Transact SQL) Reference

基于嵌套游标的更新

Nested Cursor based update

nested

cursor

sql-server-2008-r2

reporting-services

sql-update