Tableau Interview Questions and Answers
Tableau is a powerful and growing Data Visualization tool. This is mostly used in the Business Intelligence sector. Its main purpose is to simplify raw data into a very readable and easy to understand format using interactive charts.
We have prepared a list of Tableau interview questions which might be helpful for candidates interested in getting acquainted with this data analytics tool.
Data analysis is its main use and users can create engaging visuals based on the data stored in workbooks in the dashboard. The main advantage of using Tableau is that it can be used easily by a person not having a technical background. The best features Tableau which makes it a very popular choice is:
- Data Blending
- Real-time analysis
- Collaboration of data
Most Frequently Asked Tableau Interview Questions
This is actually a trick question. There is no limit to the number of rows in a table. Large amounts of data (in petabytes) can be accessed on Tableau but it restricts the number of rows that are needed at a specific time.
Now, maybe you want to see some different data on the Y-Axis. To do that, you shall need the LOD Expression
- Go to Analytics > Create Calculated Field
- In the Calculation editor, start making changes as per your need and enter this expression
{ INCLUDE [Customer Name] : SUM([Sales]) } - When you have finished this, click OK. The newly made LOD Expression is added to Data Pane under Measures.
Note: The above Tableau interview questions and answers are a guide to a basic understanding. These are questions you must know the answer to before going on an interview.
An ATTR() expression in Tableau indicates that there are multiple values to a parameter when only one value was expected.
For example, when blending multiple data sources, the data from secondary sources are wrapped in ATTR() aggregation as Tableau was expecting only one (primary) data source.
| DISCRETE | CONTINUOUS |
|---|---|
| Data roles are counted as distinct and separate. | Data roles used to measure continuous data. |
| It can take only one value within a defined range. | Value can be anything from a finite to infinite interval |
| Represented as blue pills on shelves and blue icons in the Data window | Represented as Green Pills |
| Data Joining | Data Blending |
|---|---|
| Combining data from multiple tables but from a single source. | Combining data from multiple data sources. |
| Can be performed by making use of common columns & common data types in a data set | Can be performed either Automatically or Custom/Manual by choosing the measures to blended from multiple data sets |
This is a feature in the Marks section in Tableau. It is also known as the Detail Shelf. Detail Button is used to measure the level of detail(LOD) on a marks card.
The Rank() function in Tableau is used to assign ranks to measures(numeric values) in a data set. It is a part of the table functions on the dashboard.
Creating an Age range in Tableau can be done by following these steps:
- Create a bin and edit its field name to Age
- Right-click on the Age field after the above step
- Click on Age > Create Bins
- Change the size of the bins as per requirement
- Now, drag this pill to your visualization
Two measures in Tableau can be combined and represented in a graphical format. This shall use Dual Axis which combine two or more measures at the same time for easy understanding of data.
Parallel Aggregation is a new feature under Data Vectorization in Tableau. Its aim is to reduce the time it takes to run multiple queries by allowing them to run “parallel” during the same time.