Learning Objectives

After completing this unit, you’ll be able to:

• Connect to a table of data in Tableau.
  
• Navigate the Tableau Public web authoring interface.
  
• Manage basic metadata.
  
• Build a simple viz.
  

Connect Your Tableau Public Account

To get started, connect to your Tableau Public account in the Playground window to the right. If you don’t already have a Tableau Public account, sign up for one now, and be sure to activate your account before starting this interactive unit. We provide you with more detailed instructions in the first unit of this module if you need them.

The playground resets if your Tableau Public login session expires or if you refresh the page before completing the unit. We recommend completing this unit in one sitting.

Connect to Data and Create an Extract

This module is for training purposes only. It does not indicate Love Productions, Ltd., relating to The Great British Bake Off, endorses Salesforce or its services.

The first thing to do in any new analysis is to connect to data. We use data about viewership across seasons of the Great British Baking Show.

1. Download the csv now and save it to an easy location, like your desktop.
   
2. Navigate to Connect to Data. Click the New Data Source icon in the toolbar
   
3. In the Connect to Data dialog, select Upload from computer.
   
4. Navigate to where you downloaded the data and choose GBBO viewership subset.
   
   This is the Data Source tab in Tableau. The left pane shows the tables (as tables, tabs, or sheets) available to you. To the right is the canvas where you can build the data model. At the bottom is the data grid. As you can see, the table is already on the canvas.
   
   At the top of the canvas, you should see the automatic name of the data source: GBBO viewership subset.
   
   
5. Select the name to highlight it, and then rename the data source GBBO. (This step won’t be graded, but if you skip it, your screen might diverge from the instructions later on.)
   
6. This is the only data you need for this exercise, so select Sheet 1 in the bottom bar. Tableau automatically creates an extract of your data—it may take a moment.
   

Explore the Authoring Environment

This is the authoring environment of Tableau. Let’s take a look at what it contains.

• The left pane is the Data pane. At the top you can see what data source you're connected to; it should say GBBO.
  
• Below is the list of data fields. Each one has a data type icon in front. This data set has a date field, several text (or "string") fields, and several numerica fields.
  
• There's also a horizontal line in the middle of the field list. Fields above the line are dimensions. Fields below the line are measures. This is an important concept but it's beyond the scope of this unit. For a deeper understanding of dimensions and measures, read Dimensions and Measures, Blue and Green.
  

Update Metadata

While Season and Episode are numeric, they should be considered dimensions.

1. Drag the Episode field above the line in the Data pane and drop it.
   
2. Drag the Season field above the line as well.
   

The field list above the line should now include Airdate, Episode, Network, Season, Theme, and Measure Names.

Create a Viz

Let's start by defining our analytical question. In case you're not familiar with the Great British Baking Show, it's been running since 2010 and has lived on three networks: BBC One, BBC Two, and Channel 4. When the network switched to Channel 4, longtime judge Mary Berry and hosts Mel and Sue left the show. We want to know if this impacted viewership.

To find out, we want to create a viz of the viewership numbers by airdate and network. Note: Ratings and viewership numbers use fake data but follow real-world trends.

1. Drag the My Viewership field from the Data pane to the Rows shelf. You can also double-click the My Viewership field.
   
   This sums up the values in that field across the entire data set and displays a single mark. We can see from the axis that the total about 4.2K.
   
2. Click the Text icon in the toolbar to see the exact value: 4,235. (In this data set, Viewers is in millions. It's always important to know the units in your data!) But that's overall. What about by Network? Segment this viewership number to total viewers per network.
   
3. Drag Network to the Columns shelf.
   
   Your single mark is now three, in a bar chart. BBC Two has the lowest viewership, then BBC One, then Channel 4. But that's not really a fair comparison, is it? Each network hosted multiple seasons of the show, and you need to see the trends over time.
   
   
4. Drag Network from the Columns shelf to the Color shelf on the Marks card. This converts the viz from a bar chart with three bars to a stacked bar chart where Network is encoded with color. Pretty nifty, huh? Now add a date field to the viz.
   
   
5. Drag Airdate to the Columns shelf. Now those text labels are a bit busy. We can turn them off.
   
6. Click the Text icon in the toolbar to turn off the mark labels. With date in the mix, you can see that as the show grew more popular, viewership increased year over year to a peak in 2016, the last year it was hosted on BBC One. Viewership dropped off on Channel 4 and held more or less steady for a few seasons, but has seen a recent upswing.
   

Publish Your Viz

But what's an analysis worth if no one sees it? Time to publish to Tableau Public!

1. From the area above the toolbar, select Publish As. You can also select Publish As from the File menu.
   
2. On the Publish Workbook dialog, enter a name for your viz. Make it something fun, like, My First Viz on Tableau Public!
   
3. Select Publish.
   

Congratulations! You’ve just created and published a viz!

Resources

• Trailhead: The Tableau Desktop Workspace
  
• Tableau Help: Dimensions and Measures, Blue and Green