Data Meets Maps: A Guide to Tableau Data Layer

In Tableau, you can add a data layer to a map to show additional data or information on top of the map. A data layer is a layer of data that is added to the map and can be used to display points, lines, or polygons on the map.

To add in an extra data layer to a map in Tableau, follow these steps:

1. Select the “Map” mark type from the “Show Me” menu.
2. Drag a dimension to the “Columns” shelf and a measure to the “Rows” shelf. The dimension should contain a field with geographic data, such as a country or state field.
3. Drag a dimension to the “Color” shelf to differentiate the different elements in the data layer.
4. Drag a measure to the “Size” shelf to show the size of the elements in the data layer.

You can customize the appearance of the data layer by right-clicking on the chart and selecting “Format.” From here, you can change the color scheme, font, and other visual properties of the data layer.

Data layers can be used to show additional data on top of a map, such as the locations of stores or the distribution of a particular variable. They can be useful for visualizing the relationships between geographical data and other data, and for identifying patterns and trends in the data.

In Tableau, maps are created by linking a data source containing geographic information, such as longitude and latitude coordinates, to a map visualization. The data layer is the layer that holds the geographic information and is used to create the map.

To add a data layer to a map in Tableau, you will first need to connect to your data source that contains the geographic information. Once your data is connected, you can drag the geographic dimension to the Columns or Rows shelf and the measure you want to display to the Color, Size, or Label shelf. Then, you can choose the map type you want to use, such as a filled map, symbol map, or a dual-axis map.

You can also use the built-in Tableau Maps or you can add your own custom maps by using the Tableau Map Source feature. To do this, you will need to have a map in a specific format such as Shapefile, KML or GeoJSON, and then use the Map > Background Maps > Map Layers to import your custom map.