Hierarchies

Data is oftentimes arranged in a pecking order, mirroring what we see in the outside world. We can rank data just as we would a family tree, starting with great grandparents and moving down through the generations.

In data, we call this a hierarchical structure. A hierarchy in Tableau is the mechanism Tableau uses to allow you to organize your data this way.

When you load your data into a worksheet, Tableau will automatically assemble a hierarchy. If you see something that is off or the organization of the data looks wrong, then you may want to create a custom hierarchy.

To do so, you can start in the Data pane. Drag a field that you want in your hierarchy and you will be prompted to give the new hierarchy a name. You can then continue to add new items to your hierarchy or can drag fields to different positions in the hierarchy to re-order it as necessary.

If we still work for an online retailer, but are instead focusing on all sales within the accessories department, we might need to establish a custom hierarchy.

We might start with a label for accessory type, then move on to a sub style then to an additional descriptor field. In the case of hoop earrings, the accessory type would be ‘jewelry’, the sub style would be ’earrings’, and then the additional descriptor would be ‘hoops’.

Organizing your data in this manner comes into play with visualizations too. While best practices dictate that you keep it simple, you want to make sure that your visualization still properly shows trends and other key takeaways from your analysis.

If you have a field from a hierarchy in a visualization, you can click on the plus sign or the minus sign to add or remove layers of your hierarchy as necessary. You can always remove a custom hierarchy later on by right-clicking on the hierarchy and selecting Remove Hierarchy.

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