3 Replies Latest reply on Nov 4, 2010 11:32 AM by Robert Morton

    Data Blending Problem

    David Stein

      I'm not sure this is a "basic" question, but I don't know where to ask it. Please forgive me if I posted it in the wrong place.


      I'm currently working with Tableau 6 beta, and we are considering a purchase of the full fledged product. However, I need to "sell" it to management first. Tableau 6 allows blending of data from different data sources. My problem is simple (at least to me).


      I have a Sales Backlog (the products still in production which have yet to ship) and Purchasing Backlog (Products with the same part numbers and revisions which have yet to be received) data sources.


      My first worksheet is titled "Customer Health" and it shows the Sales Order Backlog amount per customer by a calculated field called "Time Period". The periods are Past Due, Next Month, and Future and they are Red, yellow, and green respectively.


      Therefore a Project Manager can look at Acme Rockets, see a bunch of red which means their products are overdue.


      I want him to be able to click the region and have that reflected on another worksheet (in a dashboard) or worksheets and to show the corresponding Purchase Order Backlog Records by Week/Month or whatever.


      The point is if I have a bunch of part number 'Rocket123' that's Past Due for Acme, what do I have coming in for purchase orders that can immediately fulfil that.


      The problem is that I cannot include Part Number in the Customer Health Worksheet because if they click in the Red "Past Due" area, they'll only get one part number, not the entire section.


      I cannot pass Part Number directly to the second worksheet. When I created the second worksheet by manually creating relationships between the SO Backlog and PO Backlog on Part Number (identically named field) I can get Purchasing Backlog (total) on that chart, but cannot break that out into time periods or listing Purchase Order Numbers to review, etc. I only get the total backlog per Part number.


      Now, I've created a linking data set which is a distinct list of part numbers as a separate data set and tied the PO and SO data sets to that, but I still can't accomplish my goal.


      If you are still reading, thank you for taking the time to read this.


      Can anyone advise me as to how I can accomplish my goal?

        • 1. Re: Data Blending Problem
          James Baker

          (Prefix question: do your SO and PO come from different databases, so you have to use data blending and can't just join the tables?)

          • 2. Re: Data Blending Problem
            Joe Mako

            It sounds like you want to filter on "Region" between two worksheets with different data sources.


            To do this Region will have to be on both worksheets, and it sounds like it is what the user will be clicking on in the source sheet, so that one is good, but on the destination sheet, is the "Region" field at least on the Level of Detail shelf? With the field existing in both, you create a Action using Selected Fields to have the action work across data sources.


            See http://www.tableausoftware.com/community/support/kb/filter-data-sources for more details.


            If this does not help, can you attach a example packaged workbook that represents the issue you are dealing with?

            • 3. Re: Data Blending Problem
              Robert Morton

              Hi David,


              I think I understand your question and it's a bit more nuanced than simply linking two sheets with the same LOD field.  The challenge you're describing is that the main sheet shows coarse-grained order priority based on "Time Period", but you want to filter the second sheet based on the fine-grained "Part Number" field.  You describe that you can't filter the second sheet on "Time Period" because that information is specific to the data source (and calculated field) that exists only in the first sheet.  Is this correct so far?


              I'll try to post an example later, but I believe you can do the following:

              * Leave the first sheet the way you described it, with the simple coarse-grained breakdown of orders by priority (i.e. "Time Period")

              * Use Data Blending for the second sheet.  The primary data source will be the same data source you used in the first sheet (Sales Backlog).  The second data source will be "Purchasing Backlog", and the two data sources should be linked on the field "Part Number".  First drag "Time Period" and "Part Number" from the primary data source onto the sheet's 'Level of Detail' shelf on the Marks card.  Then drag the date field (aggregated by Week/Month as you described) and the "Part Number" field from the secondary onto the viz, e.g. on Rows.

              * Finally on your dashboard use the first sheet as a filter (right-click on the sheet top border and choose 'Use as Filter').  This should set it up to filter the second sheet on "Time Period", which is the field they have in common.  Now when you select items from the first sheet it should automatically show you the corresponding Part Numbers (and related date aggregates, etc.) on the second sheet.


              Does this help?  I know I could describe it better with an example but I won't be able to get to that right away.  If you post some example data in the format of your own data sources then it'll be even easier to relate the example solution to your specific needs.