Connecting to Your Data

When you first launch Tableau Desktop, the start page has a blue column on the left side labeled Connect. It has several choices for connecting to data.

  1. To open a new Tableau workbook (file) with data, click an option in the list and follow the prompts.
  2. Eventually, you’ll be taken to a new Tableau workbook.
  3. In Tableau, only the data shown in the workbook’s data source tab is available to work with, so it’s good to always review the data as the first step to starting a new project. Steps for this exist in the accordions below.
  4. When you’re happy with your data source, you can move on to creating a visualization.

Reminder: Tableau Desktop is not like MS Excel – you do not create spreadsheets in Tableau; you connect to existing spreadsheets (or other data sources) to create visualizations.

When you first open Tableau, you'll choose a way to connect your data

The blue sidebar lists all data connection options. When you see the option that most closely matches where your data is, click on the name of the option and follow the prompts.

For example, if you'd like to connect to an Excel spreadsheet, you'd click the words "Microsoft Excel" at the top of the "To a File" section.

The list of data connections is split into three sections:

  • To a File:
    • This section is to connect to data that is stored in a file on your computer, such as a Microsoft Excel spreadsheet.
    • There’s a short list of common file types. If you don’t see the type of file you’d like to connect to, you can click More… at the bottom of the section to open a pop-up that lets you choose any file on your computer.
    • To a file includes options like PDF and Excel
  • To a Server:
    • This section is to connect to data that is stored on a server, such as Tableau Server or Microsoft SQL Server.
    • There’s a short list of common server types. If you don’t see the type of server you’d like to connect to, you can click More… at the bottom of the section to expand the list of options.
      Server examples are Oracle and MS SQL Server
  • Saved Data Sources:
    • If you don’t have a data source but would like to experiment with Tableau, don’t worry! Tableau has two sample spreadsheets built in. You can click either "Sample – Superstore" or "World Indicators" to open a new Tableau workbook and work with that data.
    • Tip: If this is your first time using Tableau, we’d recommend using the "Sample – Superstore" data source, which is what we’re using for all screenshots in this guide.
      Two saved data sources are built in to Tableau

After you’ve connected to your data source, Tableau Desktop will open a new workbook and place you on an empty Worksheet tab. Before you start working, you should review your data for accuracy.

  1. Click the Data Source tab in the bottom left of the workbook.
    Data source is the very bottom left tab
  2. You’ll see a screen that looks similar to this:
    there are four main sections to the data source page
    1. In the left sidebar, Connections is where you can click Add to add a new connection.
      For example, perhaps you have an Excel file with orders from 2019 and a second Excel file with orders from 2020. You would click Add to bring the second Excel file into Tableau.
    2. Below Connections is the Sheets section, which lists all sheets in that data source. For example, this Sample - Superstore Excel file has three tabs: Orders, People, and Returns.
    3. In the top right area is the exact table(s) that Tableau is using for data. Here, the Sample - Superstore data source has 3 sheets (Orders, People, and Returns), but  Tableau is only accessing data in the Orders sheet.
    4. The bottom right will be occupied by a spreadsheet displaying all data from those table(s) that Tableau has available for you to work with. This is a visual representation of C. Here, this spreadsheet is the contents of the Orders table.
  3. Pro Tip: You can rename a column by double-clicking the heading.
    Rename is simply doubleclick

In Tableau, you can work with an unlimited number of data sources. The only requirement is that there is a  field to connect the sheets to each other.

For example, let's look at the Sample - Superstore data source. One table, Orders, contains all orders placed at the store with columns like Customer Name, Sale Price, Product Category. There is a second table, People, with columns like People (which holds the customer's name), Address. We can match up the Customer Name field in the Orders table to the People field in the People table to combine the two tables into one bigger table (the corresponding fields don't need to have the same column name - just as long as they contain the same information!).

To join two tables together:

  1. If your sheets are in different data sources, connect the second data source using the Add button above the existing connection.
    Add is in top right of connections panel
  2. Check that all tables you’d like to use are listed in the Sheets column on the left. If they aren't, re-join your connection above.
    sheets is below connections on left
  3. Drag and drop your second table from the left into the larger section at the right.
    Drag the sheet name to the big white space on right
  4. The new table will automatically be connected to the first via a SQL Inner Join, which keeps only overlapping fields (see this excellent article on SQLBolt to learn more about joins).
    The new table appears to the right of existing table
    • The large spreadsheet preview will update accordingly, so you can also refer to that to see what the new data looks like.
  5. You can click the Venn Diagram icon to bring up choices for the SQL Join, including adjusting which fields to join on.
    You have a choice between right join, left join, inner join, and outer join
  6. Repeat for any other data sources or tables you'd like to connect to. When the spreadsheet displayed in Tableau has all fields and data you'd like to work with, you're ready to move on to creating a visualization.