Essential Tableau Interview Questions & Answers: Beginner to Advanced

Tableau is a really useful application for analyzing and displaying data, which is what most businesses use to make choices these days.

To get the most out of it, you’ll need the appropriate people on board, particularly trained Tableau specialists who can transform massive amounts of data into elegantly displayed insights and information.

As everyone knows, those professionals are extremely valuable, but they are also difficult to locate. If you miss the mark, you may end up with data tales and insights that aren’t particularly impressive.

Here is a selection of the most insightful Tableau interview questions to ask candidates as part of a skills test you may use to assess their Tableau proficiency. Therefore, let’s explore Tableau interview questions and answers.

Essential Tableau interview questions

In the below section, we’ll review frequent Tableau interview questions, categorizing them as beginner, intermediate, or advanced. Finally, we’ll discuss scenario-based interview questions, which are an excellent method of determining a candidate’s experience level.

Beginner-Level Tableau Interview Questions

For entry-level employment that requires the usage of Tableau, you may be asked basic questions regarding the tool. The purpose is to determine if you have a reasonable understanding of basic ideas. The questions can range from comparing the software to other BI tools to outlining the various JOIN kinds.

Let’s look at some interview questions for beginners.

Why Tableau?

This question may appear to be very subjective, but it gets right to the heart of the matter: Tableau is a tool for more than just “making pretty charts”; it’s also a tool for extracting insights from unprocessed data. After all, the purpose of a business intelligence tool is to deliver business intelligence!

How does Tableau Compare to Other BI Tools?

Even if you don’t know much about other business intelligence tools, you might be able to discuss the distinctions between Tableau and Excel charts.

Tableau has several advantages over other business intelligence solutions, including:

• A user-friendly interface: the drag-and-drop capability enables even untrained users to quickly ramp up and begin creating charts.
• There are numerous ways to link your data using Tableau, including relational databases, flat files, and web sources, among other data sources that the application supports.
• Design flexibility: Tableau’s versatility enables users to create bespoke visuals.
• A helpful user community: Tableau’s huge and active user base makes it simple to get your questions answered.

One disadvantage of Tableau is its pricing approach. At $70 per user per month, that equates to an annual licensing cost of $840 (before any sales discounts are applied). The cost is high!

What Data Sources can You Connect to?

Numerous data sources are accessible with Tableau, including:

• Relational databases include PostgreSQL, Oracle, MySQL, and Microsoft SQL Server.
• NoSQL databases, including Cloudera, Cassandra, and MongoDB Impala cloud-based warehouses, including Snowflake, Azure, and BigQuery.
• Flat files include text files, CSV files, and Excel spreadsheets.
• Web information, including HTML tables, web APIs, and Google Analytics
• Hadoop Tableau natively supports Hadoop and can connect to Hadoop Distributed File System (HDFS), Apache Hive, and Apache Spark.
• Additional data sources include Informatica, Teradata, IBM DB2, SAP, and others.

Apart from these data sources, Tableau also provides an SDK for data connections, which enables outside developers to design unique connectors for additional data sources.

How do You Connect to Them?

The Start page’s Connect pane will display a list of data connectors. If you need to connect a new data source to a worksheet that you have already opened, you may either click on the Tableau logo in the upper left corner or click on Data Source at the bottom right of the page to return to the Connect pane and choose Add next to Connections.

What are the Join Types in Tableau?

Tableau generally supports the following types of joins:

• Inner join: Only rows with matching values in both tables are returned by an inner join.
• Left join: A left join yields the matching rows from the right table as well as every row from the left table. It returns NULL values if the correct table contains no matches.
• Right join: All of the rows from the right table and the corresponding rows from the left table are returned by a right join. It returns NULL values if the left table contains no matches.
• Full outer join: A full outer join retrieves all rows from both tables. It contains the non-matching rows with NULL values for the missing columns as well as the matched rows from both tables.

How to Join Data in Tableau?

Tableau allows you to perform joins by dragging and dropping tables from various data sources in the Data Source tab > “Drag tables here” box. After dropping the first table, right-click on it and select Open. It will display the join dialog box. Drag your second data source into the box and select the join type that you require. To close the dialog window, click the x icon in the upper left corner.

What is the Difference Between Joining and Blending?

Tableau offers two methods for combining data from several sources: joining and blending. However, the methods used to integrate the data are different.

Joining is the process of connecting data from various tables in the same data source by using a shared field. Joining combines the data from the connected tables to form a new, flattened table.

Contrarily, blending links data from various sources together on a common field, but it does not compile the data into a single, flattened table. Rather, blending preserves the distinct data sources and does independent queries on them. Blending is important when dealing with big data sets or when individual data sources must be kept as granular as possible.

What is the Difference Between a Live and an Extract?

There are two methods to connect to data in Tableau: extract connection and live connection. The primary distinction between these two connection types is how Tableau communicates with the data source.

Tableau is immediately linked to the data source when it has a live connection, which allows it to query the data source in real-time while you work with the display. However, when dealing with big data sets or intricate queries, live connections may be less effective and slower than extract connections.

In contrast, when an extract connection is made, Tableau makes a static duplicate of the data source and saves it in a format unique to Tableau, known as a “data extract.” This extract comprises only the data required for your study, hence improving performance and reducing the burden on the data source. When necessary, extracts can be manually updated or refreshed on a schedule.

What is a Dimension vs. a Measure?

In Tableau, a dimension is a categorical variable that characterizes data, whereas a measure is a numerical value that may be aggregated or computed. Dimensions are generally used to slice and group data, whereas measures are utilized to compute and examine data.

What is a Discrete vs. a Continuous Value?

A continuous value is a numeric value that can have any value within a range (150.38 lbs, 6 ½ hours, etc.). In contrast, a discrete value in Tableau is a separate value that can be counted (number of dogs in the park, number of rainbow hues, etc.). Generally, continuous values (in green) are used for numerical data, and discrete values (in blue) are used for categorical data.

Intermediate- Level Tableau Interview Questions

For mid-level to senior positions, you should anticipate being questioned on advanced Tableau issues. If the work needs a thorough understanding of the technology, you will be expected to hit the ground running by advising on dashboard design best practices and implementing rather sophisticated concepts. Let’s review a few such questions that you might be asked.

Best Practices for Designing Dashboards

Dashboard design is a fairly regular question that comes up during Tableau interviews. Talk about important topics, such as audience-focused design, clutter removal, smart use of colors and forms, and the type of chart that best represents the information you want to provide.

Another essential feature is the ability to control user flow inside a dashboard. It should never feel “stuck” to the user while engaging with the dashboard. Rather, the dashboard should be made so that the user can easily dig down into a tile, click on it, expand the data into a new view, and then go back to the home page.

What is the Order of Operations?

The order of operations, also known as the query pipeline, is the sequence in which actions or operations are performed in Tableau. When you add filters to your dashboard, they will run in the order specified by the order of operations. You’ll observe that certain processes may cause unexpected outcomes when they conflict with one another.

What are Parameters, Sets, and Groups?

Features like groups, sets, and parameters let users “slice and dice” the data in various ways.

Parameters: Parameters are user-defined values that enable users to personalize their visualizations by modifying values such as filters, calculations, and reference lines. Parameters add flexibility and engagement to visualizations by allowing users to dynamically alter the data displayed in them. Users can additionally add parameter actions to increase the interactivity of their visualizations.

Sets: Custom fields known as sets are used to aggregate related data elements together according to a shared criterion. Sets are useful for filtering and generating unique computations based on the set’s members. When creating a set, a logical expression that specifies the requirements for inclusion is used. What is a calculated field?

A calculated field in Tableau is a field that is created by performing calculations on existing fields in a data source. Calculated fields can be used in the same way as any other field in a Tableau visualization, including being used as dimensions or measures, or for filtering or grouping data. After they are generated, sets can be utilized in visualizations, filters, and computations.

Groups: Users can group data points together depending on a given field. Groups are formed by choosing individual values from a field and putting them under a single label. Groups are important for establishing data hierarchies and simplifying complex visuals. Groups can also be used to filter and create custom calculations.

While all three elements enable users to personalize their visuals, their purposes and applications differ. Sets provide the grouping of related data points; groups give a means of assembling data points according to a certain field; and parameters offer flexibility and interactivity.

What is a Dual Axis?

In Tableau, a dual axis is a technique for combining two independent plots onto a single axis. It enables users to compare two measures or sets of data using various scales or units of measurement.

Begin by adding two distinct measurements to the same row, either from the Rows or Columns menu. Right-click on the second measurement and select Dual Axis. The metrics will now be plotted on the same chart but with two distinct axes.

Advanced-Level Tableau Interview Questions

For professions that need advanced knowledge of Tableau, such as Tableau Developer responsibilities, you must be able to demonstrate competency in using advanced capabilities such as Level of Detail (LOD) expressions, improving workbook performance, and satisfying the company’s security requirements. Let’s have a look at some sample questions that might be asked in the interview.

What are LOD Expressions?

LOD expressions are used to accomplish more granular aggregations than the view’s original level of aggregation allows. LOD expressions are classified as FIXED, INCLUDE, or EXCLUDE.

• A FIXED LOD computes a value for a certain set of dimensions, regardless of the view’s other dimensions.
• An INCLUDE LOD includes additional dimensions in the view while computing a value for a given level of dimensions.
• In the end, an EXCLUDE LOD removes certain dimensions from the display while computing a value for a given level of dimensions.

What are Actions?

In Tableau, actions are a collection of interactive behaviors that enable users to browse and interact with data representations. In Tableau, there are various kinds of activities, such as:

• Filter: Applies the same filter to several views;
• Highlight: Highlights crucial information while turning off others;
• Go to URL: Links the user to an outside source, which may be a file, a webpage, or another Tableau workbook;
• Go to Sheet: Facilitates moving between a Tableau workbook’s sheets, dashboards, and stories;
• Change Parameter: This lets users alter the parameters to update the visualization dynamically; and
• Change Set Values: Users can dynamically change the visualization by selecting a subset of elements to include in the analysis.

How do You Restrict Access to the Data?

There are multiple ways to limit user access to data in Tableau, including row-level security, column-level security, and user-level security. Here’s a quick rundown of each strategy:

• User-level security: This technique limits access to Tableau content according to a user’s login information. You may specify which users in Tableau have access to particular workbooks, views, and data sources by implementing user-level security.
• Row-level security: Using the user’s login information, row-level security limits access to particular rows of data in a dataset.
• Column-level security: This technique limits access to particular data columns in a dataset by using the user’s login information.

You can make sure that only authorized users access particular data in your Tableau environment by utilizing user-level, row-level, and column-level security. This can help you keep data private, discreet, and secure.

How Do You Increase the Performance of a Slow Workbook?

There are a number of techniques you may employ to boost performance if your Tableau workbook is operating slowly.

• Optimize data sources: Inadequate data source optimization is a major contributing factor to Tableau’s inefficient workbook performance. You should make sure your data source is appropriately optimized by eliminating pointless joins, eliminating useless fields, and appropriately aggregating data in order to increase performance.
• Optimize your workbook: Another option to boost efficiency is to simplify the layout, remove unneeded data and sheets, and limit the usage of sophisticated calculations and visualizations. To increase performance, you could also think about minimizing the amount of dashboard components and filters.
• Utilize data extracts: To improve workbook efficiency, utilize pre-aggregated subsets of data known as data extracts. Tableau’s performance may be enhanced by employing data extracts to cut down on the volume of data it must process.
• Use filters: Filters can help Tableau function better by reducing the quantity of data it needs to process. Filters can be used to eliminate extraneous data from the view or to limit the amount of data that appears in your visualization.

What is the Difference Between .twbx And .twb?

You must provide a thorough response to one of the most common Tableau interview questions.

.twbx

Together with the data source, the.twbx file contains all the information needed to construct the visualization. This compresses the entire package of files, which is known as a packed workbook.

.twb

Instructions on how to communicate with the data source are contained in the.twb file. When creating a visualization, Tableau will first examine the data source before using an extract to create the visualization. Since it merely includes instructions and the data source must be attached separately, it cannot be shared on its own.

Explain the Difference Between Tableau Worksheet, Dashboard, Story, and Workbook.

Similar to Microsoft Excel, Tableau employs a workbook and sheet file structure.

• Workbooks are made up of sheets, which might include dashboards, stories, or worksheets.
• A worksheet includes the data pane, shelves, and legends in addition to a single view.
• A dashboard consists of a number of different worksheet views.
• A story is a series of dashboards or worksheets that collectively provide information.

Scenario-based Tableau Interview Questions

You might occasionally be given a visualization evaluation, which could be time-based or a take-home task. Let’s look at a few scenario-based interview question samples.

How Do You Handle Null and Other Special Values?

Tableau is unable to plot fields that have null values or those have zeros or negative values on a logarithmic axis. You can select among the following options by clicking on the indicator that Tableau provides in the view’s lower right corner:

• Filter Data: Uses a filter to exclude null values from the visualization. In that scenario, the null values are likewise not included in any of the view’s computations.
• Display Data at Default Position: This option displays the data on the axis at a predetermined place.

How Can You Optimize the Performance of a Dashboard?

There are several strategies to improve the dashboard’s performance, including:

• Make as many fields and records as possible. You can use extract filters or remove fields that aren’t needed from your display.
• Utilize action and parameter filters instead of quick filters to reduce the amount of filters you utilize. The query loads are decreased by these filters.
• Because average functions take longer to process than min/max functions, use min/max instead of average.
• Make more use of boolean or numerical computations than string ones. Integers and booleans are processed by computers far more quickly than texts.

Boolean > int > float > date/time > string

Which Visualization Will Be Used in the given Scenarios?

1. To present aggregated sales totals across a range of product categories and subcategories.
2. To display the duration of an event or activity.
3. To demonstrate quarterly profit growth.

For the cases provided, we would make use of the following visualizations:

• Treemap
• Gantt chart
• Waterfall chart

How Do You Make the Webpage Dynamic?

Start by displaying the Map by Sales. It displays the name and sales of the state.

• Navigate to the dashboard.
• Double-click the ‘Webpage’ option from the ‘Objects’ menu.
• Click “Ok” without entering a URL in the dialog box that displays.
• Choose “Action” after clicking on the Dashboard in the menu.
• After clicking “Add Action,” choose “Go to URL.”
• Enter ‘https://en.m.wikipedia.org/wiki/’ into the URL field. Choose “State” by clicking on the arrow next to it.
• After selecting “Select option,” click “Ok.”
• The Wikipedia page for California is now displayed when you click on any state, such as California.

Design a View to Show Region Wise Profit and Sales.

To display region-specific profit and sales, simply follow these steps:

• Move the sales and profit fields to the rows shelf.
• To the Columns shelf, drag the Region field.

However, the interviewer can be searching for your Tableau mapping skills in response to such inquiries. To better display region-specific profit and sales, you must adhere to the following steps:

• To view the State field, double-click on it.
• To switch the mark type from Automatic to Map, go to the Marks card.
• Bring the Marks card’s Region field to color.
• Drag the State, Sales, and Profit fields to the Marks card’s Label.

Additional Interview Questions on Tableau

What does it mean to have data visualization?

The process of visually representing data or information is known as data visualization. Graphs, charts, bars, and many other easily observable objects can be used. Tools for data visualization make it simple to view and comprehend the data.

Explain why data servers are essential in Tableau.

A data server in Tableau has two tasks to complete. One benefit is that it enables you to maintain your data, including definitions, aliases, datasets, and previous computations, in sync with the server for remote access. This enables more honest completion of any assignment. Thus, it provides you with speedy access and security.

Second, you can download some of the data you require to run a report or visualization to your local computer if you have a data server. It is simple to obtain from the internet via the server.

What’s a heatmap? Describe a case.

A heatmap is a kind of data visualization where a data collection is displayed using several color tones. An extreme value (high intensity or density) can be seen in the deepest shade of a given color. It is typically applied when comparing two or more metrics.

Learning about the anatomy of the human body and determining its temperature based on the temperature of its many organs are two easy ways to use a heatmap. The red sections will indicate the areas with the highest temperature if red and yellow are combined.

In Tableau, what is a context filter?

When more than one filter is used, context filters can enhance the dashboard’s appearance. No matter what other filters are applied, a Tableau filter affects each and every row in the dataset. We can reduce the amount of the dataset by using a context filter. To cut down on time, the remaining filters will subsequently be applied to the reduced dataset.

What is a tableau server?

Tableau dashboards created on the Tableau desktop can be arranged, edited, shared, and collaborated on using Tableau Server. Because the administrator can determine how much authority each user has and only employees will see the data, it is safer for organizations. A user may, for instance, be limited to viewing the data, editing it, or both.

Final Words

Before you begin your job search, it is the greatest time to get ready for that crucial Tableau interview. Engaging in user groups, publishing your work, and doing the other tasks recommended in this Tableau Interview Questions article will help you prepare for a better job interview and provide concrete evidence of your work.

Throughout the interview, don’t forget to use examples or talk about your pertinent Tableau experience to support your responses. These questions and answers will help you prepare for a Tableau interview for a Data Analyst/Scientist position. Best of luck!

Frequently Asked Questions

What type of skill is Tableau?

Tableau is a data visualization and analytics skill used to create interactive dashboards and insights from data.

How do I prepare for a Tableau interview?

To prepare for a Tableau interview, focus on mastering key skills like data visualization, creating dashboards, and using calculated fields. Review Tableau’s core features, practice with sample datasets, and build projects showcasing your skills. Study basic SQL, as it’s often required, and be ready to explain your analytical approach and problem-solving strategies. Familiarize yourself with Tableau functions, filters, and parameters, and be prepared to answer scenario-based questions about optimizing performance or solving visualization challenges.