Tableau Box Plot

Tableau Box Plot is useful for graphically visualizing the numeric data, group by specific data. Let us see how to Create a Box Plot in Tableau with an example. For this Tableau boxplot demo, we are going to write the Custom SQL Query on the SQL Server Data Source.

How to Create a Tableau Box Plot

Please refer Connecting Tableau to SQL Server to understand the configurations. The custom SQL query that we are going to use for this Tableau report is:

-- SQL Query to create a Box Plot in Tableau
SELECT ProdCat.EnglishProductCategoryName, 
       ProdSubCat.EnglishProductSubcategoryName, 
       Geo.EnglishCountryRegionName, 
       Geo.StateProvinceName, 
       Geo.City, 
       Geo.PostalCode, 
       Geo.IpAddressLocator, 
       Prod.EnglishProductName, 
       Prod.Color, 
       Prod.DealerPrice, 
       Cust.FirstName, 
       Cust.LastName, 
       Cust.Gender, 
       Cust.YearlyIncome, 
       Cust.EnglishEducation, 
       Cust.EnglishOccupation, 
       Fact.OrderQuantity, 
       Fact.TotalProductCost, 
       Fact.SalesAmount, 
       Fact.TaxAmt, 
       Fact.OrderDate
FROM DimProductSubcategory AS ProdSubCat
   INNER JOIN
     DimProduct AS Prod ON ProdSubCat.ProductSubcategoryKey = Prod.ProductSubcategoryKey 
   INNER JOIN
     DimProductCategory  AS ProdCat ON ProdSubCat.ProductCategoryKey = ProdCat.ProductCategoryKey 
   INNER JOIN
     FactInternetSales AS Fact ON Prod.ProductKey = Fact.ProductKey 
   INNER JOIN
     DimCustomer AS Cust ON Fact.CustomerKey = Cust.CustomerKey
   INNER JOIN
     DimGeography AS Geo ON Cust.GeographyKey = Geo.GeographyKey

In this example, we are going to create a boxplot in Tableau. For this, first drag and drop the Sales Amount from Measures Region to Rows Shelf, and Color from Dimensions region to Details field present in Marks Shelf.

Tableau intelligence automatically creates the Bar Chart, but we want to create a Box plot so, please select the Box plot option from the Show Me window as shown below

From the below screenshot, you can see the Tableau Boxplot.

Let me drag and drop the English Country Region Name from Dimensions to Columns Shelf. It will create a box plot for each country

You can hover over the mouse on the box plot to see the Median, Upper Quartile, Lower Quartile, and the Whisker values.

Change Colors of a Tableau Box plot

In this example, we show you how to change the colors of a Tableau Boxplot boxes. Tableau provides two different approaches to this.

First Approach: Please right-click on the box plot and select the Edit.. option from the context menu.

Once you select the Edit.. option, a new window called Edit Reference Line, Band, or Box will open to style the box plot.

Second Approach: Go to the Format menu and select the References Lines… will open the Format Reference Lines tab.

Let me change the Fill color to the Red pallet.

Next, we are changing the Border width and border color for Tableau box plot

Lastly, we are changing the Tableau Whiskers width and color

Change Colors of a dots in Tableau Box Plot

This example explains how to add colors to the dots in the Tableau boxplot. For this, drag and drop the English Country Name from Dimensions Region to the Color field in Marks Shelf, as shown below. It means each country has its own color

Change the Size of a dots in Tableau Box Plot

In this example, we will show you how to change the size of the dots in a box plot. For this, drag and drop the Order Quantity from Measures Region to Size field in Marks Shelf, as shown below.

Create Categorical Box Plots in Tableau

Here, we show how to create a boxplot in Tableau for each color within a region. For this, drag and drop the Color from Dimensions Region to Columns Shelf.

By default, the box plot displays the horizontal lines (or dots), and they are the compressed box plot. Because it is difficult to draw the box plots for aggregated data, so, let’s remove the aggregated measure by unchecking the Aggregate Measures available in Analysis Menu, as shown below.

Now you can see the box plot for each color present in a region.

Horizontal Tableau Box plot

In this example, we will show you how to change the default vertical box plot into a horizontal box plot by swapping rows and columns

Below screenshot will show you the horizontal box plot in Tableau