Top 20 Tableau Interview Questions

Top 20 Tableau Interview Questions
Top 20 Tableau Interview Questions & Answers

Q1. What is a tableau?
Ans: Tableau is an innovative Tableau Software data visualization software. It can readily connect to almost any information source, such as corporate information storage, Microsoft Excel, or Web-based information. Tableau enables instantaneous understanding by transforming information into interactive dashboards called visually attractive visualizations. It takes only seconds or minutes rather than months or years, and it can be achieved with a drag and drop interface that is simple to use. Tableau is a business intelligence software that enables someone in just a couple of clicks to connect to data and then visualize and create shareable interactive dashboards with some other information. Every Excel user can learn it easily, but it is powerful enough to solve even the most complicated analytical problems. It only requires seconds to securely share your results with others.

Q2. What are data visualization and tableau?
Ans: Data visualization is the process of visually representing your textual data. Tableau is one of the leading software in this virtualization field. It has been the leader in the Gartner magic quadrant. It is so popular for its performance, dynamic & user-friendly with drag and drops and minimal coding.

Q3. How does tableau work?
Ans: Although Tableau can analyze databases, you don’t need to know anything about databases to use Tableau. You don’t need Tableau. Indeed, Tableau is intended to enable entrepreneurs with no technical training to effectively analyze their information. 

Tableau has three easy concepts: 

  • Connect the Tableau- Connect it to any database you want to evaluate. Note that the data is not imported by Tableau. Rather, it straight queries the database. 
  • Analyze- Analyzing information is viewed, filtered, sorted, calculated, reorganized, summarized and so forth. It implies analyzing information. By placing areas of the information source on the Tableau worksheets you can do all these things using Tableau. Tableau displays information in conventional controllers and query languages (such as SQL and MDX) and displays a visual assessment of the information when you drop a field on a worksheet. 
  • Share- By exchanging workbooks with other Tableaux users, adding outcomes into apps, such as Microsoft Office, printing in PDF or using Tableau Server to publish or integrate your opinions across your organisation you can share your outcomes with others.

Q4. How many types of charts are in the tableau?
Ans: There are 13 types of charts in Tableau:

Bar chart: A bar chart shows information with the bar length proportionate to the variable’s value in rectangular bars. When you pull a dimension into the Row shelf and evaluate it to the Column shelf, Tableau automatically generates a bar chart.

Line chart: A line chart brings together different information points in view. It offers easy ways to visualize a series of values and it is helpful for seeing trends in time or predicting future values. Tableau adds sales as SUM and shows a straightforward line chart.

Pie chart: A pie chart view that shows how different product categories contribute to total sales.

Map: Maps are one of Tableau’s most successful kinds of charts and are also among the easiest to produce charts.

Scatter plot: Scatter plots provide an excellent way to perform ad hoc analysis. In Tableau, by putting a measure in a row shelf and another measure in a row shelf, you build a scatter plot. We can ask Tableau to compare two numerical values by doing this. As a default view for this, Tableau selects a scatter plot by default.

Gantt chart: A Gantt graph shows the advancement over a time period in the value of a job or resource. It is widely used during a period of time in project management and other variation studies. Thus, time is an important area in the Gantt chart.

Bubble chart: To display data in a cluster of circles use packed bubble charts. Dimensions define the different bubbles and measurements set the size and color of each circle.

Histogram chart: A histogram represents accurately how numerical data are distributed. It estimates a continuous variable’s likelihood distribution.

Bullet Chart: A bullet chart is a bar chart that replaces dashboards and meters. The graph is a variation. The results of the main measure are compared with one or more other measures using a bullet chart.

Heat maps: A heat map is a graphical depiction of the information with colors for each value in a matrix. “Heat map” is a new word, but there are long-term shading matrices.

Highlight table: You generate a highlight table in Tableau by putting one or more sizes in the stand of the columns and one or more on the shelf of the rows. Then you choose Square as the sort of mark and position a measure of concern on the Color shelf.

Treemaps: To show information in nested rectangles, use treemaps. The structure of the map and the measurements are used to identify the size or color of each rectangle.

Box-and-whisker plots: The box plots are also known as box-and-whisker plots. They display the value distribution in an axis. Boxes are the mean 50% for the information, the upper two quartiles for the distribution of the information.

Q5. What are aggregation and disaggregation in Tableau?
Ans: Aggregation is the simple concept of averaging values in a given data set column. If a specific report contains the historical change in prices of a product, the aggregation will help in finding its average value. In most cases, Tableau automatically aggregates a given set of data.

Disaggregation is the opposite of averaging, which can be helpful if a user wants individual data points. Both aggregated and disaggregated data can also be utilized in a single worksheet.

Q6. What is an embedded data source? How is it different from a published data source?

Ans: An embedded data source contains information that is connected to a workbook. A published data source works independently.

Q7. What is a dual-axis?

Ans: It is a function in Tableau that showcases two scales of two measures in a single graph. This is very similar to the function found on Microsoft Office products where a single graph has line and bar elements. In most cases, it has either two X or two Y axes.

A dual-axis is typically used to show trend lines and historical data. An example would be total revenue vs profit across 12 months.

Q8. What is data blending in Tableau?

Ans: Data blending is an advanced joining of two different data sources. For example, one data source contains annual sales of a product in different countries and the second data source contains countries and their monthly profit and loss values. A simple join won’t work in this case because of different levels of segregation. The first step will be to aggregate the values in the second data source based on the year and then perform a join. All these steps can be completed with great ease in tableau. Because tableau can identify the common field of country and year between two data sources and perform a post aggregate join by itself.

Q9. What is LOD in tableau?

Ans: Full form of LOD is Level of Details. LOD is used to define the level of granularity to compute values at data source and visualization levels. It is applied using calculated fields. The first keyword defines the type of LOD expression that is to includes or excludes a specific field while performing the aggregation on the required field.

Q10. What is kpi in tableau?

Ans: Tableau makes it easier to analyze the effectiveness of a company based on some key indicators by the use of Key Performance Indicators in shape cards. The first step is to create a calculated field and then mark the values as success and failure based on the required parameter. Then plot a chart using a dimension and the created calculated field and change automatically to shapes in the marks card. Then assign success and failure to Kpi in a shape card for simplified and better understanding.

Q11. How to create a donut chart in a tableau?

Ans: There is no direct way to create a donut chart in tableau but there are two tricks to create it. If you want to show a donut chart in a sheet, first of all, plot a pie chart and then add another measure to the rows shelf. Now you can see two pie charts on the sheet change the color of the second pie chart to match the background color and reduce its size, now right-click on the second instance in the rows shelf and select dual axis then remove all the details which are not required. The second way to create a donut chart will work only in a dashboard. First, create a pie chart in a sheet and import it to the dashboard then place a circular image with the same color as of the background and move it to the center.

Q12. What do you know about the .twb and .twbx extension?

Ans: The .twb extension indicates an XML document containing all selections and layout made in a Tableau workbook. The document does not contain any data. On the other hand, the .twbx extension indicates a zipped archive that contains.twb and external files such as background images and extracts.

Q13. What data types are supported in Tableau?

Ans: The common data types supported on Tableau include,

  • Boolean
  • Date
  • Date and Time
  • Text or String
  • Whole Number
  • Decimal Numbers
  • Geographical Value

Q14. What are the notable features of Tableau?

Ans: The significant features of Tableau are a mandatory addition in almost any outline of the most common Tableau interview questions. The noteworthy features of Tableau as a business intelligence tool are as follows,

  • Data blending and real-time analysis capabilities
  • DAX analysis function
  • Data collaboration and data notifications
  • Mobile-ready and shareable dashboards
  • Support for a list of native data connectors
  • Creation of no-code data queries
  • Support for importing all sizes and ranges of data
  • Data highlighting and filtering

Q15. What is a Tableau Worksheet?

Ans: The Tableau worksheet is one of the basic components of working with Tableau. It is a single view sheet containing various visualizations. It contains different elements such as filters, Data and Analytics pane, shelves, Show Me menu, cards, and legends. In addition, users can also find a blank area on the Tableau worksheet for creating visualizations. You can use one or multiple Tableau worksheets for the creation of workbooks, stories, and dashboards.

Q16. What is the hierarchy in Tableau?

Ans: In use cases involving work with large volumes of data, the possibilities of faults in the organization of data increase prominently. Tableau provides the facility of creating hierarchies to ensure the proper organization of data. The interesting factor is that hierarchies are in-built into user data on Tableau, enabling easier management, organization, and tracking of data.

Q17. What is meant by Tableau Data Server?

Ans: The tableau server acts as a centre man between Tableau clients and the information. Tableau Data Server permits you to transfer and share information separately, safeguard data set associations, just as reuse computations and field metadata. This implies any progressions you make to the informational collection, determined fields, boundaries, nom de plumes, or definitions, can be saved and imparted to other people, taking into consideration a protected, halfway oversaw, and normalized dataset. Moreover, you can use your worker’s assets to run questions on extricates without having to initially move them to your neighborhood machine.

Q18. Explain about bins in Tableau?

Ans: Tableau bins are practically equivalent to holders that are of equivalent size and that store information esteems compared to the bin size. The bins bunch a set of information into gatherings of equivalent size. This gives an orderly appropriation of information. 

In Tableau, we can take information from any discrete field and make bins. Even though Tableau clients for the most part use measure fields to make numeric bins. Bins are valuable in information examination as they give an efficient information range that encourages us to put together data better and find designs without any problem. Bins are made by utilizing determining fields in Tableau.

Q19. List out a few points that help to increase the performance of Tableau?

Ans: Following are some of the significant points that help the tableau to increase the performance:

  • Utilize an Extract to make worksheets run quicker 
  • Diminish the extent of information to diminish the volume of information 
  • Decrease the number of imprints on the view to dodge data over-burden 
  • Attempt to utilize whole numbers or Booleans in counts as they are a lot quicker than strings 
  • Shroud unused fields 
  • Use Context channels 
  • Lessen channel utilization and utilize some elective method to accomplish the same outcome 
  • Use ordering in tables and utilize the same fields for separating 
  • Eliminate superfluous sheets and calculations.

Q.20 How to add custom color to Tableau?

Ans: To add custom color in Tableau, you need to follow 3 steps

  • Create custom colour code and build it in “Preferences.tps”
  • Drive to Documents→ My Table Repository→ Preferences. tps
  • Add a word for custom colour code

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