Filters and Parameters in Tableau: When to Use Them

Overview

When building a dashboard in Tableau, the analyst may want to filter many worksheets with a single filter selection. Tableau has three ways of making this possible: global quick filters, filter actions, and parameters. Global quick filters will filter each worksheet on a dashboard as long as they each contain that dimension. Filter actions use a "control" worksheet to filter other worksheets on the dashboard based on the selected elements in that sheet. Parameters allow the user to use what would otherwise be a quick filter as a filter if the dimension is different on each sheet.

In this post, we will explore the advantages and disadvantages of using each filter type and how to approach different use cases that call for dashboard filters.

Global Quick Filters

Advantages

Global quick filters are very useful when creating dashboards that contain worksheets that all use the same data source. For example, in a dashboard that displays the dataset in both text and visual forms, global quick filters give the flexibility to present the filter in a variety of formats: single value dropdown, multiple values list, wildcard match, etc. They also allow the user to show an aggregation of all marks with the "(All)" filter.

Disadvantages

Of course, the main disadvantage of global quick filters is that if the analyst has a dashboard with worksheets that each use a different data source, they do not work. This is especially problematic when the component worksheets in a dashboard are displaying similar concepts but are built using datasets optimized for the specific type of worksheet the user needs (table, bar chart, map, etc.). In this case, even if the datasets all have the same columns and data types, the analyst is forced to find an alternative solution.


Filter Actions

Advantages

Filter actions are best used when the user should interact with a specific sheet that acts as the "control." Examples of this may be a text table that lists product categories or a bar chart that lists sales numbers. In this case, the user may want to see other information about specific marks in these worksheets. By setting up filter actions, users can filter other worksheets in a dashboard by selecting the relevant marks.

Filter actions address the problem presented by global quick filters and the use of different datasets. Even if all the worksheets in a dashboard use different datasets, filter actions allow the analyst to assign connections between two fields in different datasets. Analysts can assign a single field connection, multiple fields, or all fields. This Tableau Knowledge Base article demonstrates how to set up the filter and the data relationships.

An example of this might be a text table of product sales in a given sales period. The user wants to see the various worksheets on the dashboard filtered by a specific product or products. In the product sales table, the user can CTRL-click the products they want to see and the other worksheets will be filtered accordingly. This can even work across dashboards.

Disadvantages

While filter actions allow the analyst to filter different datasets with a single click, it takes away the variety of ways the data can be filtered that global quick filters allow. The user must interact with the control worksheet to filter the other sheets connected to it. A simple quick filter (not a global one) that filters the control worksheet will not propagate to the other worksheets in the dashboard. For dashboards where a user might want to filter all worksheets by a given dimension, e.g., date or geographical region, a global quick filter or parameter would be better.


Parameters

Advantages

Parameters address the problems of both global quick filters and filter actions: they allow the user to use a single dropdown or list that affects all connected worksheets in a dashboard and allow the analyst to connect the filter across datasets. Essentially, they act as an independent filter that can then filter the various worksheets. We won't cover how to set them up (they are linked to above) but by using parameters, analysts have greater power over how their worksheets are filtered. As long as the data types match, filters on each worksheet can be controlled by a parameter.

Disadvantages

Unfortunately, parameters have their own limitations. Whereas global quick filters have seven ways to be represented on a dashboard, parameters only have four. Parameters cannot make multiple selections in a filter, e.g., with a list of checkboxes, and they do not have the "(All)" aggregate choice of quick filters. While the inability to select multiple items in a filter cannot be circumvented, the data can be structured to include an "All" row that aggregates the relevant data for that mark. This is not optimal, since the analyst must make this consideration when preparing their data for use in Tableau, but it is the only workaround we have come across.


Conclusion

We have covered the three types of dashboard filters in Tableau and their strengths and weaknesses. As we continue to use Tableau in future projects, we hope to find solutions to some of the shortcomings of these filtering methods. If you have any questions or have a suggestion to work around the challenges we've written about, feel free to leave them in the comments below!

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