Innovative Tableau

Chapter 30. 3 Ways to Make Magnificent Maps: Tip 3

Combine Generated and Custom Lat-Long Coordinates

As of Tableau version 2018.1, you can create a dual-axis—or, layered—map, even with a combination of generated and custom latitude/longitude coordinates. This makes it possible to combine specific addresses that require custom latitude and longitude pairs in the underlying data with less granular geographic data that uses the generated coordinates in Tableau.

This has many applications. One of my favorite examples is when I worked with a client that sold its product exclusively online but had competitors that had traditional brick-and-mortar locations. We created a dual-axis map with the client’s sales on one axis and the store locations of the client’s competitors to identify threats and opportunities.

Let’s keep going with this barbecue example to illustrate how this is done. Let’s pretend the year is 2036. I have retired from writing about Tableau and got the crazy idea to compete with the greatest barbecue restaurants on the planet by shipping Kansas City barbecue via drone. I have a data file that shows my online orders by city and another file with the restaurant locations from Chapters 28 and 29.

If you are in a similar situation with two separate files, the first thing you must do is a full outer join to bring the dataset with the custom coordinates into the dataset that will use the generated coordinates.

Here’s how the data prep piece looks within Tableau Desktop: