13 Replies Latest reply on Sep 2, 2016 4:19 PM by David Li

    Detail Mark on Line Graph

    Tammy Miles

      When I add a Dimension to the Detail so that it appears when I hover over the graph, the line of my chart don't render on thos points.  Has anyone else experienced this?

      Notice in the first Image the line is connected to the points where there is a label.  I add the label description to the Details Mark and the line is no longer able to render at the points (see 2nd image) 

       

      Any help or thoughts would be greatly appreciated,

      Tammy

      without detail.PNG

      with Detail.PNG

        • 1. Re: Detail Mark on Line Graph
          David Li

          Hi Tammy, have you tried dropping the dimension on the Tooltip mark instead?

          • 2. Re: Detail Mark on Line Graph
            Tammy Miles

            I just switched it to the Tool Tip and that did fix the rendering problem.  Do you have any thoughts on why the Details would cause the issue?

            • 3. Re: Detail Mark on Line Graph
              David Li

              I'm glad that worked!

               

              The reason that the Detail mark causes this issue is because using Detail marks changes your level of detail. That is, if when you add a dimension to the detail mark, it will create breakdowns/aggregations in the view based on that dimension (assuming that new ones are needed). You can think of the Detail mark as the same as the Label, Color, or Size marks, except that it doesn't change any visual features like those marks do.

               

              On the other hand, things added to the Tooltip mark won't change the level of detail in most cases.

              • 4. Re: Detail Mark on Line Graph
                Tammy Miles

                Thank you David,

                 

                I am still bothered by what this is doing though.  The Dimension I added to the Detail is level that the aggregation is taking place.  Basically this datasource has been pre-aggregated.  If I highlight the chart the datapoints are in the right position, it's the line that has the problem.  It completely bypasses the datapoint and connects the next datapoint.  The only difference is the Detail i added is a 'null' value.  Maybe it should be a hard blank?

                • 5. Re: Detail Mark on Line Graph
                  David Li

                  Hmm, that's strange. Without being able to look into the data or the packaged workbook, I can't really say what could be causing it.

                  • 6. Re: Detail Mark on Line Graph
                    Tammy Miles

                    I can add the datasource file if that would help

                    • 7. Re: Detail Mark on Line Graph
                      David Li

                      Sure. A packaged workbook (within which you've set the data source to use an extract) would be the best.

                      • 8. Re: Detail Mark on Line Graph
                        Tammy Miles

                        Here is the packaged Workboot

                        • 9. Re: Detail Mark on Line Graph
                          David Li

                          To illustrate what's happening, take a look at what happens when I change the [Description] field to a Size mark. (For others, I'm also attaching an image of the dimension domain.)

                          Notice that all the separate dots have different sizes. This means that Tableau is treating each one as a separate aggregation (series). So the continuous line consists of all the records where [Description] is Null. And all the individual points are actually different single-point line graphs that are distinguished by the [Description]. That means that there's a separate (one-point) line for "Change in Adlucent", for "Increase in PPC Spend", and so on.

                           

                          When you change this to a Tooltip mark, what happens by default is that the dimension no longer contributes to the LOD and instead uses the ATTR() aggregation, which just gives the value of that dimension for the records in a cell/point without changing the breakdown.

                           

                          Does that make sense?

                          • 10. Re: Detail Mark on Line Graph
                            Tammy Miles

                            It does make since, but i'm still bothered.  So if I really wanted this as part of the detail so that a user could view it, it would be treated like a one to many even though for example all records in the source data with date 04/25/2015 only contain 1 value of Decription?

                             

                            Sorry to ask so many questions, but this is only the end of the second week of using Tableau and without any kind of training, I am learning as I go.

                             

                            Thank you again

                            • 11. Re: Detail Mark on Line Graph
                              David Li

                              You're doing a great job for only being in the second week!

                              So if I really wanted this as part of the detail so that a user could view it

                              I should point out that you don't need to add this to the level of detail (or the Detail mark) for users to view it. If, for instance, you wanted it to show up on the viz, you could put ATTR([Description]) onto the Labels mark.

                              it would be treated like a one to many even though for example all records in the source data with date 04/25/2015 only contain 1 value of Decription?

                              Basically. But don't think of this as a one:many relationship. Instead, think of this in terms of aggregating records from your underlying data. Consider the Superstore sample data set. If you put a dimension like [Category] into the LOD, it will break down the underlying records and aggregate the ones with matching [Category] together. If you have three Categories, you'll end up with three buckets/aggregations. Even though you consider [Dimension] to be a kind of descriptive attribute and not a breakdown dimension, Tableau doesn't know the difference. It treats it just like it would Category, and so it tries to aggregate the records so that ones with the same [Description] are in the same bucket. That's why you need to tell it that [Description] is an attribute and not a true dimension.

                              • 12. Re: Detail Mark on Line Graph
                                Tammy Miles

                                Thank you again.  You have been very helpful and very patient with me

                                • 13. Re: Detail Mark on Line Graph
                                  David Li

                                  You're very welcome!