3 Replies Latest reply on Aug 10, 2019 3:48 PM by John Sarantos

    Issues with Creating a Timeline

    joanna Peng

      Hey Tableau Community,


      I work for a clinical trials network, and I'm trying to construct a timeline for each of our active protocols that includes the date of each milestone completed. You can think of a milestone as an event within the development of our clinical trials. I tried to follow the instructions found at this website: Timeline Chart in Tableau - AbsentData; however, as you can see in the first screenshot attached, an issue arises when I choose multiple types of milestones/events in my filter (protocol milestone Id). The goal is to get the multiple milestones I choose to align themselves on each protocol's timeline. Interestingly, if you look at the second screenshot, when I only choose one milestone from the "Protocol Milestone Id" filter, I get correct dates corresponding to their correct locations on the timeline. But this is no help because I need to see multiple milestones on each timeline.


      The way the data is organized is that each "event", properly called a protocol milestone, has four dates associated with it: The actual start date, actual end date, target start date, and target end date (consider these targets as anticipated or hoped for. I used the Protocol Milestone Target End Date. Instead of using protocol milestone names, use the dimension Protocol Milestone Id, which is just the number form of the name.


      I would greatly appreciate if you all could help me find a solution to my dilemma. Attached is a packaged workbook in Tableau version 2019.2. Three data sources are attached. When linking across them, use the Dimension "protocol", but all the data you need should be in the protocol_milestones_tst database.


      Much appreciated,




      Message was edited by: joanna Peng I just replaced the Tableau workbook in the attachments section so that the data bases are extracted. I also tried changing the date pill from exact to year, and the same issue arose: when I added more than one Protocol Milestone Id to my filter, issues came up. Hope you can help me find a solution1 Many thanks, Joanna

        • 1. Re: Issues with Creating a Timeline



          I think you may need to extract your data prior to packaging the workbook,

          the one attached is asking to connect to Tableau Online.

          Alternatively, you could mock up some fake data similar to your own

          and post that.


          I'm not sure if I caught the gist, but I think that one issue may be that it is

          plotting the x-axis as an exact date (like 4/2/2014 and 8/5/2014), so the milestones

          of the same year are not lining up. If you right click on the Protocol Milestone Date,

          and select continuous Year, then I think it will work better.

          But I may be completely off base.

          • 2. Re: Issues with Creating a Timeline


            I took a quick look at it, I have not yet quite caught the gist,

            but I feel like it is related to the blending of the datasources.

            Would it be possible to join them instead?

            I very quickly did a join (probably not on the right fields),

            but it seemed to work better.

            Please see attached workbook v2018.1 attached in the original Forum Thread:

            Issues with Creating a Timeline

            • 3. Re: Issues with Creating a Timeline
              John Sarantos

              Hi Joanna,


              Another key point here is you need to have at least one row for every date in the time-frame you are working with.  Your data source has specific dates here and there according to the milestones, but it does not have a truly continuous date field for you to compare your other various points in time to.  Notice in that blog post you reference they are only working with one date field, and ALL the events have a connection to that field.


              You can address this either by altering your data source or by building a date scaffold.


              This post give a bunch of links to date scaffolding: Data Scaffolding in Tableau


              This blog post is also helpful for understanding date scaffolding:  https://www.kenflerlage.com/2019/03/date-scaffold.html


              I hope this information helps to move you along your path!


              Please mark/let me know if this was helpful/answered your question.


              Thank you,