Bringing in More Data with Joins in Tableau

In this tutorial, we explore how to bring in more data using joins in Tableau. You will learn how to connect multiple data sources, create joins, and utilize the merged data for analysis. An example using order details and product CSV files is demonstrated to show each step in detail including data import, edit mode, join creation, and chart building with the unified dataset.

What will you learn

• How to import multiple data sources in Tableau.
• Understanding and creating joins between datasets.
• Differences between data blending and data joining.
• How to utilize merged data fields in charts.
• How to create calculated fields using multiple datasets.
• Best practices for managing redundant fields.

Takeaway notes

• Begin by importing your datasets into Tableau.
• Always use edit mode to create a join, not dragging directly to avoid inadvertently creating data blending.
• Joins are created upfront, while data blending merges data only when used in a chart.
• The type of join (inner, left, right, full) can be adjusted based on analysis needs.
• Use common fields (e.g., Product ID) to establish the join between datasets.
• Manage redundant fields by hiding them to simplify your dataset.
• Calculated fields in Tableau can use variables from multiple joined datasets.

Practice questions

1. How do you import multiple data sources into Tableau?
2. What is the primary difference between joining and data blending in Tableau?
3. How do you access edit mode to create a join?
4. What are the different types of joins available in Tableau?
5. What steps do you take to manage redundant fields in a dataset?
6. How does Tableau automatically identify common fields for joins?
7. How can you change the type of join in Tableau after it has been created?
8. Provide an example of a calculated field that uses variables from two different datasets.
9. What is the significance of hiding redundant fields in a joined dataset?
10. Describe the process of creating a calculated field in Tableau.
11. How can you differentiate fields from different data sources in a joined dataset?
12. What happens to the data in a blend versus a join when it is used in a chart?
13. Why might you prefer joins over data blending for certain analyses?
14. How does a join affect the way dimensions and measures are displayed in Tableau?
15. Create a chart using fields from multiple data sources to demonstrate the use of joins in Tableau.