Successful businesses forecast, make decisions and develop strategies based on data. Tableau is a data-driven tool used for data interpretation.
Importance of Tableau as a BI and visualization tool
One of the most well-liked business intelligence (BI) and visualization solutions available today is Tableau. It gives users the option to visualize data in several ways and can be used to discover patterns and trends.
It can be applied to gather data, analyze it, and reach conclusions. It is adaptable and applicable to many different sectors for more complex analytics.
It enables users to produce and distribute interactive maps and dashboards to understand their data better. Developers and administrators can utilize Tableau to create in-depth reports and visual data representations.
Tableau is a flexible tool that both small and large enterprises can utilize. Due to its widespread use has a lot of potential for use in various industries, including marketing, finance, and human resources.
Most often asked Tableau interview questions and their responses.
What is data visualization?
Answer: Data visualization is the presentation of data in a graphical or pictorial format. It is often used to explore and understand data, find patterns and relationships, and communicate findings. Users can use data visualization to represent many data types, including numerical, categorical, and temporal data.
What is Tableau?
Answer: Tableau is a powerful visualization tool. It can visualize data in any format, including reports, graphs, maps, and data visualizations. Tableau can be used to understand trends and make informed decisions. It is utilized globally by business experts and data analysts to make data-driven judgments.
What Are the Data Types Supported in Tableau?
Answer: Several data types can be used in Tableau, making data analysis and visualization much more effortless. These data types include text, numbers, dates, times, boolean values, clusters, and maps.
What are the advantages of using Tableau?
Answer: Tableau offers a wide range of advantages, such as
Answer: In Tableau, parameters are used to control the behavior of worksheets and reports. Tableau parameters can be specified in various ways, including using Tableau’s embeddable parameter boxes, text fields, and calculation fields. Tableau also supports external references to parameters from other sources.
Tell me different ways to use parameters in Tableau
Answer: Tableau parameters are a robust tool that may be applied in numerous ways to produce the desired results. Using these, you may determine how the data will be displayed, filter and sort the data, and personalize the data visualizations.
In other words, There are four typical uses for parameters. Filters, bins, reference lines, and computed fields are among them.
What are continuous and discrete field types?
Answer: In Tableau, fields can be either continuous or discrete. Continuous fields are quantitative values that can be added, subtracted, and averaged. Examples of continuous data include Sales, Profit, and Quantity.
Discrete fields are quantitative values that can be counted but not added, subtracted, or averaged.
What is Tableau Server?
Answer: You can use the Tableau server to host and administer workbooks, reports, dashboards, and data sources created with Tableau Desktop.
Tableau Server can be installed on a Windows or Linux server. Users can access Tableau Server via a browser to build new workspaces, publish reports and dashboards, and share them with other users.
What are data extract files in Tableau?
Answer: Data extracts are saved subsets of data you can utilize to enhance performance or benefit from Tableau features that aren’t supported or available in your original data.
You can use filters and other limitations to lower the overall amount of data when creating an extract of your data.
What is a Tableau Dashboard?
Answer: Tableau Dashboards are a fantastic method to present complex data sets in a simple way to understand. Tableau Dashboards can offer insights that might otherwise be challenging to gain from raw data by combining charts, graphs, and tables.
Users can quickly create and share dynamic data representations using a Tableau Dashboard for data visualization.
State the components of Tableau Architecture
Answer: Primarily, there are five components in Tableau Architecture
1. Data Server: The main component of Tableau Architecture
2. Data Connector: Acts as an interface between Data Sources and Data Servers
3. Components: Application Server, VizQL Server, Data Server
4. Gateway: Handles processes like URL Rewriting, Load Balancer, etc
5. Clients: Tableau Desktop, mobile applications, web browser
What is the difference between published data and embedded data sources in Tableau?
Answer: Tableau supports both public and embedded data sources. While embedded data sources are saved in a workbook, published data sources are saved on Tableau Server or Tableau Online.
Published data sources can connect to various users, whereas embedded data sources can only be used by the person who produced them. The embedded data sources require a separate refresh schedule, while published data sources require a single refresh schedule.
What is Tableau Reader?
Answer: Tableau Reader is a data visualization and analysis software that helps users explore, understand, and act on data. It is designed to be easy to use, regardless of experience level.
Tableau Reader provides various data exploration, analysis, and presentation tools, making it a powerful tool for data scientists, business analysts, and information professionals.
What are Filters? How many types of Filters are there in Tableau?
Answer: The act of filtering involves deleting a specific value or range of values from a result set. The Tableau filtering function supports simple field value scenarios and complex calculations or context-based filters.
Types of Filters: Extract filters, data source filters, context filters, dimension filters, and measure filters.
What are the different types of joins in Tableau?
Answer: Tableau supports four types of joins: Inner Join, Left Join, Right Join, and Full Outer Join. It can link up to 32 tables in a single data source.
What is the Difference between Joining and Blending?
Answer: Joining and blending data in a Tableau represent different ways of connecting the data in your analysis.
Joining data means adding the data together while blending means taking the data from one table and combining it with data from another table.
Joining is the default action when you connect data in Tableau, but blending can be more efficient if you want to change the data before you analyze it.
What is the difference between a Heatmap and a TreeMap?
Answer: Heatmaps and TreeMaps are both visualizations in Tableau that are used to compare data. Heatmaps use color to show how data points are related, while TreeMaps use size and color to show how data points are associated.
Heatmaps are best used when you have many data points and want to find patterns. TreeMaps are best used when you have a smaller number of data points and want to show the data hierarchy.
What is the difference between shared axis charts, combined axis charts, and dual axis charts?
Answer: When creating visualizations in Tableau, there are three main chart types to choose from: the shared axis chart, the combined axis chart, and the dual axis chart. They differ regarding how data is displayed, and axes are linked.
A shared axis chart, also known as a simplex chart, is a type of chart that is used to show relationships between two dimensions. It is simple to create and easy to understand
A combined axis chart combines the features of a bar and line chart. It displays data on two axes and the relationship between items on the axes.
Dual axis charts show the relationship between two sets of data.
What is the difference between twb and twbx file extensions?
Answer: The metadata for a Tableau workbook is stored in an XML file known as a Tableau workbook (.twb). It includes the worksheets, the data source connection information, and the workbook’s layout and format.
A packed file called a Tableau packaged workbook (.twbx) contains the workbook XML and any external files required to support its data sources.
What are the different types of functions generally used in Tableau?
Answer: Tableau offers a wide variety of functions for usage in Tableau calculations.
What is the story in Tableau?
Answer: A story is a series of visuals that function as one to convey information. Stories can support ideas by clarifying how facts relate to one another and how decisions impact outcomes.
Explain different connection types in Tableau.
Answer: Tableau can connect to all the popular data sources which are widely used, such as:
Cloud: Microsoft Azure, Google BigQuery, Salesforce
Other Sources using ODBC
Connection to websites through a web data connector
The following are more data connection types that Tableau supports.
What is a Page shelf?
Answer: In Tableau, a page shelf is a tool for data organization. They’re like folders in a file system, and you can group them by topic or date. They are ideal for arranging complex data.
It can also be defined as – To properly understand how a particular field affects the other data in a view, a Page shelf enables you to divide a view into several pages.
What is the RANK Function in Tableau?
Answer: Tableau’s RANK function is a helpful feature that lets you order the numbers in a data set. This function is used to rank values in a data collection to one another or to determine the top or bottom values in a data set.
In other words, the Rank function, as the name suggests, is used to give the rank to any measure (number related) included in the data set. For instance, the highest value is ranked highest, and the lowest is ranked lowest.
What is the difference between INDEX and RANK in Tableau?
Answer: Tableau provides two methods for sorting your data: INDEX and RANK.
INDEX sorts data by a numerical value, while RANK sorts data by rank.
The INDEX primarily deals with the record’s physical location, and incremental numbers are assigned based on the records’ physical order.
RANK primarily concerns the record’s value, which means records with higher values are ranked higher, and records with lower values are ranked lower.
What are some limitations of Tableau?
Answer: The following are the limitations of Tableau:
Tableau can only work with cleaned data and focuses primarily on visualization.
Lacks data modeling and data dictionary capabilities for data analysts.
When developing data logic and dashboards, there is a lack of version control and collaboration.
Tableau does not offer the option of using scheduling to refresh reports automatically.
Developers must produce fresh visuals rather than import them.
Supports only a 16-column table with limited formatting
The parameters cannot be updated automatically; manual action is necessary.
Dashboards are not responsive, so the developer needs to design a separate dashboard for mobile and desktop.
Scaling this product across a big company is highly expensive. Compared to BI tools that are more affordable and complete.
How is Tableau different from other BI tools?
Answer: The primary difference between the two is that Tableau has a far more user-friendly and intuitive interface than other business intelligence systems. Unlike other programs that may require a certain amount of technical knowledge and understanding, anyone with a basic grasp of computers can learn and use Tableau.
It also has a more incredible tool selection that lets users create more complex visualizations. It is also noticeably more flexible and adaptable than its competitors, allowing users to make incredibly unique and customized representations.
Its emphasis is primarily on visual analysis than on data manipulation. Hence developers can quickly access and understand massive amounts of data.
How Can You Optimize the Performance of a Dashboard?
Answer: Tableau dashboards are designed to present data in a form that is simple to understand. Developers can enhance a dashboard’s performance to ensure the data is displayed accurately and promptly.
There are a few ways to optimize the performance of a dashboard.
Using appropriate data management methods, such as optimizing extracts and minimizing the number of fields and records.
Instead of viewing everything in one view, group related views together and connect them with action filters.
Avoid using too many filters because this will make your query more complex and take longer to produce results.
Use the query optimization in Tableau.
To reduce overhead in Tableau, lessen the number of nested computations and perform calculations wherever possible in the database.
Cut back on extra worksheets, get rid of unused worksheets, etc.
Reduce the number of blends and minimize joined tables.
What is Quick Sorting in Tableau?
Answer: Quick Sorting in Tableau is a method that helps you rearrange the order of data in your worksheet. Quick Sorting is a built-in feature of Tableau that you can use to sort your data in ascending or descending order.
To use Quick Sorting, select the data you want to sort and click on the sort button in the toolbar. You can also use the keyboard shortcut Alt + Shift + S to sort your data.
What is a Tableau worksheet?
Answer: A Tableau worksheet is an interactive data visualization that allows you to explore, work with, and understand your data. A worksheet can contain one or more visualization objects, such as charts, tables, maps, and images.
You can use worksheets to answer questions, analyze, and tell stories with your data. Worksheets are the foundation of a Tableau workbook.
What is the difference between the quick and normal filters in Tableau?
Answer: Quick filters in Tableau are more efficient than normal filters. The difference is that normal filters restrict the view data to just what is in the cells, whereas quick filters can extract data from a column that is not in the cells.
The quick filter is more efficient because it doesn’t need to go through the whole table to find the data it needs.
Mention some challenges when working with large volumes of data and how many maximum tables you can join in Tableau.
Answer: Some challenges while working with large volumes of data include: Data Storage and processing, maintaining quality and cleansing, Data Accessibility and Data Transfer, a huge requirement of Computational power, safeguarding data, etc.
Tableau’s maximum table connection depends on factors like data source, machine memory, and join complexity. There is no hard limit, but practical considerations come into the picture while performing the task.
Discuss the differences between Power BI and Tableau
Answer: Power BI possesses a user-friendly interface similar to other Microsoft applications, whereas Tableau provides an interactive interface specifically for visual analytics and data exploration.
Power BI facilitates customization through Power Query and Power Pivot, while Tableau offers the capabilities for visual modification and extension.
Regarding collaboration, Power BI interfaces with Microsoft Teams, while Tableau has its own capabilities for sharing.
Tableau is closely linked to Salesforce, while Power BI integrates well with Microsoft.
Discuss the differences between Tableau and QlikView
Answer: Tableau boasts a modern and user-friendly interface that offers convenient drag-and-drop capabilities. In contrast, QlikView features a more traditional interface.
Tableau visually presents and analyses data interactively, while QlikView provides intuitive navigation and detailed examination through associative data modeling.
Tableau and QlikView offer users a variety of data connectivity options. Specifically, Tableau provides direct connections to multiple data sources, whereas QlikView may require coding for certain types of data sources.
QlikView employs a scripting language to handle data transformations and modeling, while Tableau’s primary emphasis lies in visual data manipulation and data preparation facilitated by its data source connectors.
QlikView and Tableau are both scalable. However, when it comes to large-scale applications, Tableau may require additional settings.
Tableau’s collaboration tools offer robust functionality, empowering users to effortlessly share and collaborate on dashboards as well as reports. In comparison, QlikView provides some collaboration features, although they are not as extensive as Tableau’s offerings.
How to link Mongodb to Tableau?
Answer: The simplest way to establish a connection between Tableau and MongoDB involves utilizing the Atlas SQL Interface alongside the Atlas Tableau Connector and JDBC driver.
How to integrate R with Tableau?
Answer: Tableau Desktop is capable of establishing connections with R through the use of calculated fields. On the other hand, Tableau Server can establish a connection with a Rserve instance by utilizing the tab admin function.
What is data blending?
Answer: Tableau utilizes data blending to merge information from multiple sources and create a unified view or representation. This functionality empowers users to seamlessly combine data from various tables, databases, or file types without prior source integration.
What is data modeling?
Answer: Data modeling is the process of structuring and organizing data within Tableau. Its purpose is to enable successful analysis and visualization. This involves transforming raw data into a suitable format for analysis and reporting purposes.
Mention components of a dashboard.
Answer: The following are the main components of a dashboard in Tableau:
Worksheets: Charts or tables that visualize data using available data sources.
Images: Enhance dashboard visuals by adding images or shapes for branding and better presentation.
Filters: To let users control dashboard data display.
Containers: To organize and align visualizations in the dashboard.
Parameters: Allow users to modify dashboard behavior.
Web Pages: Enables embedding web pages in dashboards for referencing external content.
How to make a dashboard in Tableau?
Answer: To create a new dashboard, click the Dashboard button in the upper right corner of your Tableau screen. It will open a drop-down menu from which you can select New Dashboard to create a dashboard.
How to hide dashboards?
Answer: Primarily, two common ways to hide dashboards in Tableau are:
To hide specific dashboards, group them inside a container, then hide the entire container by right-clicking on it and selecting Hide Container.
To hide dashboards, place them in a layout container on the main dashboard and select Hide Container from the right-click menu.
How to sort data in Tableau?
Answer: Tableau offers various sorting options, including alphabetical, field values, and calculated fields.
Click on the field in Columns or Rows, and use the toolbar or right-click menu to sort dimensions in the desired order.
Sort multiple fields by holding Ctrl, clicking on the fields, and using the Sort option to set the order.
To sort data within a specific visualization, Right-click on a data point or field in the visualization, then select Sort from the context menu to sort the data as desired.
How to make a group in Tableau?
Go to the desired worksheet.
Find the dimension field you want to group.
Drag it from “Data” to Columns” or Rows.
Hold Ctrl and select multiple items within the field.
Right-click the selected items and choose Group.
A group will be created.
How to make sets in Tableau?
Answer: Two types of sets exist: dynamic and fixed sets. To create a dynamic set, right-click a dimension in the Data pane, then select Create > Set. For a fixed set, select one or more marks (or headers) in the visualization and right-click them, then choose Create Set.
How to embed a webpage in a dashboard?
Answer: Go to the desired dashboard, find the Web Page object in the left pane, and drag it onto the canvas. In the Web Page dialog box, enter the webpage URL to embed and adjust the size if needed. Confirm by clicking OK. The embedded webpage will be placed on your dashboard.
What are the different types of maps available in Tableau?
Answer: Maps are powerful visual tools in Tableau for presenting data. Below are the available map types in Tableau:
Proportional symbol maps
Choropleth maps (filled maps)
Point distribution maps
Density maps (heatmaps)
Flow maps (path maps)
Spider maps (origin-destination maps)
How to handle null in Tableau?
Answer: An empty field represents a null value, indicating missing or unknown information.
Below are a few ways to handle null in Tableau:
Preprocess data to handle null values before importing it into Tableau.
Other options include filtering them out, replacing them, or creating calculated fields.
Modify visualization settings to handle null values effectively based on your data’s characteristics.
How can I create a hierarchy in Tableau?
Answer: Go to the intended worksheet to make the hierarchy. Select dimensions or fields for the hierarchy. Drag the first-dimension field to the Columns or Rows shelf. Then, drag the second-dimension field next to the first one on the same shelf. Tableau visually displays detected hierarchies automatically.
What is a workbook, and can we export views or workbooks from Tableau Server?
Answer: A workbook comprisessheets, which can take the form of worksheets, dashboards, or stories. Workbooks serve as a means to effectively organize, save, share, and publish your results.
Yes, you can export views or workbooks from the Tableau server.
To export views: Open the desired view in Tableau Server, find the “Download” option in the toolbar, click it, and choose the desired export format (PDF, PNG, Excel, etc.).
To export workbooks: Select the workbook, open it, locate the “Download” option in the toolbar, and choose the export format (e.g., Tableau Workbook, PDF).
How to automate reports in Tableau?
Answer: To automate reports in Tableau, you can use Tableau’s built-in features, third-party tools, and integrations.
Ways to automate reports include using Tableau Server or Tableau Online for scheduling and subscriptions, utilizing TabCmd for command-line automation, developing custom extensions with the Tableau Extensions API to interact with external systems, and automating data fetching and report generation.
Tableau also integrates with third-party tools specializing in report automation and scheduling.
How to schedule a workbook in Tableau after publishing it?
Answer: Use Tableau Server or Tableau Online to schedule a workbook in Tableau: Publish the workbook to Tableau Server or Tableau Online. Then open the workbook on the server. To schedule it, find the “Schedule” button or option in the toolbar or “Server” menu. Configure the schedule by specifying the frequency and time using the scheduling interface.
How to do performance recording in Tableau, and How to perform load testing in Tableau?
Answer: Tableau’s Performance Recording captures key events in workbooks for analysis and troubleshooting performance factors.
To enable performance recording for a site in Tableau, the server administrator can follow these steps:
Go to the desired site.
Click on Settings and navigate to Workbook Performance Metrics.
Select “Record workbook performance metrics” and save the changes.
TabJolt is a load and performance testing tool exclusively developed for Tableau Server by Tableau.
What is a Tableau data engine?
Answer: Tableau’s Hyper data engine accelerates data processing for large datasets. It drives Tableau platforms, including Server, Desktop, Cloud, and Public, allowing for data extraction, refreshing, and querying.
What is Assume referential integrity?
Answer: The Assume Referential Integrity option in Tableau assumes the existence of referential integrity within a data source, thereby optimizing queries and operations, even in the absence of explicit declaration.
It guarantees the consistency of foreign key and primary key values in a relational database, thereby ensuring accurate relationships between tables.
What are bins in Tableau?
Answer: Tableau Bins serve as uniform containers used to store data values that correspond to or fit within a specific Bin Size. The primary objective of these Bins is to effectively divide a dataset into groups based on equal intervals or sizes. This division facilitates the creation of a well-structured distribution of the data, which in turn helps users organize information and identify patterns more efficiently.
What is the level of detail (LOD) expression?
Answer: LOD enables the computation of values at both the data source and visualization level. On the other hand, LOD expressions enable the specification of desired granularity for computation. They can be performed in more detail-oriented (INCLUDE) or less detail-oriented (EXCLUDE) levels plus completely independent levels (FIXED).
What is a backgrounder?
Answer: The ‘Backgrounder’ is a Tableau Server or Tableau Online component that manages numerous background jobs and processes. It is responsible for operations like data extractions, refreshes, subscriptions, and scheduled jobs”.
What is forecasting?
Answer: Forecasting is the process of predicting the future value of a particular measure. This task utilizes using various mathematical models dedicated to forecasting. In Tableau, the exponential smoothing model is utilized. Within this model, greater weight gets attached to recent observations compared with earlier ones within the same measure.
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