加入 3 个临时表时的问题

Question

I have an issue joining 3 temp tables.

I have such tables

1. UDT_CKB_SNAPSHOT - list of different items and events (items on sale) some promotions etc

2. FCSTPERFSTATIC - Forecast

3. HISTWIDE_CHAIN - Actuals

I am going to write the whole code but the thing that doesn't work is a join when selecting all three temp tables. Everything else works just fine (type just in case if someone wants to see the whole picture).

WITH UDT_CKB_SNAPSHOT AS
(
  SELECT  [UPC] ,[MASTERCHAINNAME] ,[EVENT_TYPE],[STARTDATE],[ENDDATE] ,[EVENT_NAME] 
  FROM [BYIntegration].[SCPOMGR].[UDT_CKB_SNAPSHOT]
  WHERE [EVENT_TYPE]='Promotion' AND
        [STARTDATE] BETWEEN '2021-09-26' AND '2021-12-08'
        
  GROUP BY [UPC] ,[MASTERCHAINNAME],[EVENT_TYPE],[STARTDATE],[ENDDATE] ,[EVENT_NAME] 
),

FCSTPERFSTATIC AS
( SELECT  [DMDUNIT],[STARTDATE],[LOC],SUM([TOTFCST]) AS 'Forecast'
   FROM [BYIntegration].[SCPOMGR].[FCSTPERFSTATIC]
   WHERE [STARTDATE] BETWEEN '2021-09-26' AND '2021-12-08'
   GROUP BY [DMDUNIT], [STARTDATE], [LOC]
),

HISTWIDE_CHAIN AS 
( SELECT [DMDUNIT] ,[DMDPostDate],[LOC] ,SUM([HistoryQuantity]) AS 'HistoryQuantity'
   FROM [BYIntegration].[SCPOMGR].[HISTWIDE_CHAIN]
   WHERE [DMDPostDate] BETWEEN '2021-09-26' AND '2021-12-08'

   GROUP BY [DMDUNIT], [DMDPostDate], [LOC]
)

**SELECT U.[UPC] AS 'Item', U.[MASTERCHAINNAME] AS 'Chain', U.[STARTDATE] AS 'Start Date', U.[EVENT_TYPE] , U.[EVENT_NAME], SUM(F.Forecast) AS 'Forecast', SUM(A.HistoryQuantity) AS 'Actuals'
FROM UDT_CKB_SNAPSHOT U  
LEFT OUTER JOIN FCSTPERFSTATIC F
on U.[UPC]=F.[DMDUNIT] AND U.[MASTERCHAINNAME]=F.[LOC] 
LEFT OUTER JOIN HISTWIDE_CHAIN A
ON  U.[UPC]=a.[DMDUNIT] AND U.[MASTERCHAINNAME]=a.[LOC] 
AND a.[DMDPostDate]=u.[STARTDATE] and  f.[STARTDATE]=a.[DMDPostDate]
GROUP BY U.[UPC], U.[MASTERCHAINNAME], U.[STARTDATE], U.[EVENT_TYPE] , U.[EVENT_NAME]**

So the issue is the line in bold italics.

I need to join all three tables on dates to make sure I select the same inventory during the same time period. Whenever I join those three tables I either get Forecast or Actuals right, but never both.

When i type this I get Forecast correct, but Actuals incorrect a.[DMDPostDate]=u.[STARTDATE] and f.[STARTDATE]=a.[DMDPostDate] (Forecast correct 6998.649, Actuals are not correct 826)

-- AND u.[STARTDATE]=f.[STARTDATE] and f.[STARTDATE]=u.[STARTDATE] (Actuals are correct 10369, Forecast not correct 8322.315)

-- and a.[DMDPostDate]=f.[STARTDATE] (Forecast correct 6998.649, Actuals not correct)

-- AND u.[STARTDATE]=a.[DMDPostDate] (Forecast correct 6998.649, Actuals not correct)

-- AND u.[STARTDATE]=f.[STARTDATE] (Actuals are correct 10369, Forecast not correct)

-- and u.[STARTDATE]=f.[STARTDATE] and u.[STARTDATE] = a.[DMDPostDate] (Forecast correct 6998.649, Actuals not correct)

When I run all three queries separately everything works but when I am selecting them one of them depending how I join STARTDATE goes wrong. I've spent almost the whole day trying to troubleshoot, but i still don't understand how I can make it work.

I will appreciate any advice.

Answer 1

When i type this I get Forecast correct, but Actuals incorrect a.[DMDPostDate]=u.[STARTDATE] and f.[STARTDATE]=a.[DMDPostDate] (Forecast correct 6998.649, Actuals are not correct 826)

-- AND u.[STARTDATE]=f.[STARTDATE] and f.[STARTDATE]=u.[STARTDATE] (Actuals are correct 10369, Forecast not correct 8322.315)

-- and a.[DMDPostDate]=f.[STARTDATE] (Forecast correct 6998.649, Actuals not correct)

-- AND u.[STARTDATE]=a.[DMDPostDate] (Forecast correct 6998.649, Actuals not correct)

-- AND u.[STARTDATE]=f.[STARTDATE] (Actuals are correct 10369, Forecast not correct)

-- and u.[STARTDATE]=f.[STARTDATE] and u.[STARTDATE] = a.[DMDPostDate] (Forecast correct 6998.649, Actuals not correct)

From your post - it seems fairly clear that joining STARTDATEs gets you the correct actuals, and joining DMDPostDate to either start date gets the right forecast.

Something thing to consider - u.[STARTDATE]=f.[STARTDATE] - this clause should have no impact to the A table join, what if you added this to the F table ON clause, and then u.[STARTDATE] = a.[DMDPostDate] to the A table clause

The way it's working now, you're left joining everything from table F to everything it can join to in table A based on the U.[UPC]=F.[DMDUNIT] AND U.[MASTERCHAINNAME]=F.[LOC], without any dates. It could be a challenge with the way it's evaluating the clauses as a result.

Dark horse answer - you don't need to join on any dates - actuals are correct when you aren't joining dates for the A table - when you use AND u.[STARTDATE]=f.[STARTDATE] it may be applying to the U/F join which could lower the forecast number.

You could also troubleshoot by joining the F and A tables separately to the U table to see if you're getting the expected values then.