Top 30 Most Common Power Bi Questions You Should Prepare For
Written by
James Miller, Career Coach
Embarking on a career that involves data analysis and business intelligence often leads to interviews where proficiency in tools like Power BI is paramount. Microsoft Power BI has become an industry standard for transforming raw data into actionable insights, making skilled professionals highly sought after. Preparing for your Power BI interview requires a solid understanding of the tool's core functionalities, from data connection and transformation to modeling, DAX calculations, and visualization. Interviewers want to see that you not only know the features but can apply them to solve real-world business problems. They assess your ability to handle data, design effective reports, and communicate insights clearly. These power bi questions cover a wide spectrum, ensuring candidates possess the necessary technical depth and practical experience. Acing your Power BI interview can significantly boost your career prospects in data-driven roles. This guide is designed to walk you through the most frequently asked power bi questions, providing concise and effective ways to structure your answers, giving you a distinct advantage in your job search.
What Are power bi questions?
Power BI interview questions are designed to evaluate a candidate's knowledge and experience with Microsoft's business intelligence platform. These questions cover various aspects of Power BI, including its architecture, components like Power BI Desktop, Service, and Mobile, and its underlying technologies such as Power Query and Power Pivot. Interviewers will ask about data connectivity, transformation processes (ETL), data modeling principles (star vs. snowflake schema), and the use of Data Analysis Expressions (DAX) for creating calculated measures and columns. Visualization techniques, dashboard creation, data sharing methods, and security concepts are also common topics. The aim is to assess a candidate's ability to connect to diverse data sources, clean and shape data, build efficient data models, write complex calculations, design compelling reports and dashboards, and effectively deploy and manage Power BI solutions. Mastering these power bi questions is crucial for anyone seeking a role involving data analysis or business intelligence using Power BI.
Why Do Interviewers Ask power bi questions?
Interviewers ask power bi questions to gauge a candidate's technical skills, problem-solving abilities, and practical experience with the platform. They want to ensure the candidate has a deep understanding of Power BI's capabilities and limitations. Questions about data transformation and modeling assess the candidate's ability to prepare data for analysis and build efficient, scalable data models. DAX questions evaluate their analytical prowess and ability to create complex calculations to derive meaningful insights. Questions on visualization and reporting test their skill in presenting data clearly and effectively to business users. Furthermore, questions about data sources, connectivity, and sharing reveal their familiarity with the broader data ecosystem and collaboration features. By asking these specific power bi questions, interviewers can determine if a candidate possesses the required expertise to connect to data, transform it, model it, analyze it, and visualize it, ultimately solving business intelligence challenges and contributing value to the organization. Preparing for these power bi questions is vital for demonstrating your readiness for a Power BI role.
Preview List
What is Power BI?
What are the key components of Power BI?
What are the data sources supported by Power BI?
What is Power BI Desktop?
What is Power BI Service?
What is DAX in Power BI?
What is Power Pivot?
What is Power Query?
What is the purpose of the Query Editor in Power BI?
What is the role of visuals in a Power BI report?
What is a filter in Power BI, and why is it useful?
What is a slicer in Power BI?
How does a slicer differ from a filter?
Which is faster among slicer and filter?
How do you import data into Power BI?
What are the basic steps for data cleaning and transformation in Power Query?
What is the purpose of a dashboard in Power BI?
What are custom visuals in Power BI?
What is VLOOKUP equivalent in Power BI?
What is an anti-join in Power BI?
What is a data alert in Power BI?
Compare star and snowflake schema.
What are the differences between measures and columns?
How do you share reports in Power BI?
What is the role of Power BI Report Server?
What are the unique features of Power BI over other BI tools?
How does Power BI differ from Tableau?
Can you export data from a Power BI report to other formats like SSRS?
What are the types of joins used in Power BI?
How do you maintain slicer and filter states across multiple pages in Power BI?
1. What is Power BI?
Why you might get asked this:
This common power bi questions assesses your fundamental understanding of the tool's definition and purpose. It's a basic screening question.
How to answer:
Define Power BI as a business analytics service and mention its primary use cases like data visualization and reporting.
Example answer:
Power BI is a cloud-based business analytics service from Microsoft. It's used to visualize data and share insights. It connects to various data sources to create interactive reports and dashboards, making data analysis accessible.
2. What are the key components of Power BI?
Why you might get asked this:
Tests your knowledge of the different parts of the Power BI ecosystem and how they interact. Essential for understanding the workflow.
How to answer:
List and briefly describe the main components: Desktop, Service, Mobile, and Report Server.
Example answer:
The key components are Power BI Desktop for report authoring, Power BI Service (cloud) for sharing and collaboration, Power BI Mobile for viewing on devices, and Power BI Report Server for on-premises deployment.
3. What are the data sources supported by Power BI?
Why you might get asked this:
Evaluates your practical experience in connecting Power BI to various data platforms, a crucial first step in any project.
How to answer:
Provide examples of common data sources Power BI can connect to, covering different categories (files, databases, cloud services).
Example answer:
Power BI supports a vast range of sources including Excel, CSV, SQL Server, Azure SQL Database, SharePoint, Oracle, web data, Google Analytics, and many SaaS services through connectors.
4. What is Power BI Desktop?
Why you might get asked this:
Focuses on the primary authoring tool. This power bi questions checks if you know where reports and models are built.
How to answer:
Describe it as the free Windows application used for connecting, transforming, modeling data, and creating reports.
Example answer:
Power BI Desktop is a free application you install on your Windows computer. It's where you perform most development tasks: connecting to data, transforming it using Power Query, building data models, and designing reports.
5. What is Power BI Service?
Why you might get asked this:
Tests your understanding of the cloud platform for distribution and collaboration, essential for sharing insights.
How to answer:
Explain its role as the online platform for publishing, sharing, collaborating, and viewing reports and dashboards.
Example answer:
The Power BI Service is the cloud-based part of Power BI. After building reports in Desktop, you publish them here to share with colleagues, create dashboards, set up data refreshes, and manage access.
6. What is DAX in Power BI?
Why you might get asked this:
A fundamental power bi questions for anyone involved in data modeling and analysis. Tests your understanding of the calculation language.
How to answer:
Define DAX as a formula language used for creating custom calculations like measures and calculated columns in Power BI and SSAS.
Example answer:
DAX stands for Data Analysis Expressions. It's a formula language used in Power BI, Power Pivot, and SSAS Tabular models to create custom calculations, such as measures (aggregations) and calculated columns, based on your data model.
7. What is Power Pivot?
Why you might get asked this:
Assesses your knowledge of the data modeling engine within Power BI Desktop.
How to answer:
Describe Power Pivot as the component responsible for creating the data model, managing relationships, and writing DAX formulas.
Example answer:
Power Pivot is the data modeling technology integrated into Power BI Desktop. It allows users to create sophisticated data models, establish relationships between tables, and define custom calculations using DAX formulas for analysis.
8. What is Power Query?
Why you might get asked this:
This common power bi questions evaluates your understanding of the data extraction, transformation, and loading (ETL) process.
How to answer:
Explain Power Query as the tool used for connecting to data sources, cleaning, shaping, and transforming data before loading it into the model.
Example answer:
Power Query is an ETL tool within Power BI (and Excel). It's used to connect to various data sources, preview the data, and apply transformation steps (like cleaning, filtering, merging, pivoting) before the data is loaded into the data model.
9. What is the purpose of the Query Editor in Power BI?
Why you might get asked this:
Focuses on the specific interface for Power Query, testing your practical skills in data preparation.
How to answer:
Explain that the Query Editor is the graphical interface within Power BI Desktop where you define and apply Power Query transformation steps.
Example answer:
The Query Editor (part of Power Query) is where you perform data transformations visually. You connect to sources, see previews of the data, and apply steps like removing columns, changing data types, filtering rows, or merging queries.
10. What is the role of visuals in a Power BI report?
Why you might get asked this:
Tests your understanding of how data is presented and communicated to users in Power BI.
How to answer:
Describe visuals as the graphical representations of data used to tell a story, highlight trends, and provide insights interactively.
Example answer:
Visuals are fundamental components of a Power BI report used to display data in a graphical format like charts, tables, and maps. They make complex data understandable, highlight key trends, and allow users to interact with the data.
11. What is a filter in Power BI, and why is it useful?
Why you might get asked this:
Assesses your ability to narrow down data for specific analysis, a core reporting function.
How to answer:
Define filters as mechanisms to restrict the data displayed based on conditions and explain their utility in focusing analysis.
Example answer:
A filter in Power BI is used to show only a subset of the data based on specified criteria. It's useful for focusing analysis on particular segments, time periods, or categories, making reports more specific and relevant to the user's needs.
12. What is a slicer in Power BI?
Why you might get asked this:
This power bi questions evaluates your knowledge of interactive filtering elements used in reports.
How to answer:
Describe a slicer as a specific type of visual that provides buttons or lists for users to interactively filter data on the report canvas.
Example answer:
A slicer is a report visual that acts as an on-canvas filter. Users interact with it directly (clicking buttons, checkboxes, or selecting range values) to dynamically filter other visuals on the report page, offering an intuitive filtering experience.
13. How does a slicer differ from a filter?
Why you might get asked this:
Tests your understanding of the user interface and interactivity aspects of filtering options.
How to answer:
Explain that slicers are interactive visuals on the report canvas, while filters can be applied in the Filters pane and are not always visible to the user.
Example answer:
The key difference is visibility and interaction. Slicers are visuals placed directly on the report page for user interaction. Filters are typically managed in the 'Filters' pane, can be applied programmatically, and might not be immediately obvious to the end-user viewing the report.
14. Which is faster among slicer and filter?
Why you might get asked this:
Probes your understanding of performance considerations in report design.
How to answer:
State that filters applied in the Filters pane are generally faster as they impact the query directly without rendering a visual interface.
Example answer:
Filters applied via the Filters pane are generally considered faster. They modify the data query before results are displayed, whereas slicers require rendering a visual element on the canvas while also applying the filter logic.
15. How do you import data into Power BI?
Why you might get asked this:
Tests your practical steps for getting data into the tool, a foundational skill.
How to answer:
Describe the process using "Get Data" in Power BI Desktop, selecting the source, and using Power Query (Query Editor) for transformations.
Example answer:
You import data using the "Get Data" option in Power BI Desktop. You select your data source type, connect, and then use the Power Query Editor to preview, clean, and transform the data before loading it into the Power BI data model for reporting.
16. What are the basic steps for data cleaning and transformation in Power Query?
Why you might get asked this:
Assesses your understanding of preparing raw data for analysis using Power Query.
How to answer:
List common transformation steps like removing columns/rows, changing data types, handling errors, merging/appending queries.
Example answer:
Basic steps include connecting to the source, removing unnecessary columns/rows, correcting data types, handling missing values (nulls), renaming columns, splitting or merging columns, and sometimes merging or appending different queries.
17. What is the purpose of a dashboard in Power BI?
Why you might get asked this:
Tests your understanding of the top-level aggregation and monitoring feature in the Power BI Service.
How to answer:
Explain dashboards as single-page canvases in the Service summarizing key metrics (KPIs) from various reports.
Example answer:
A dashboard in the Power BI Service provides a consolidated, high-level view of key metrics from one or more reports. It's a single canvas used to monitor KPIs and get a quick overview, often used by management for at-a-glance insights.
18. What are custom visuals in Power BI?
Why you might get asked this:
Evaluates your awareness of extending Power BI's built-in visualization capabilities.
How to answer:
Describe them as visuals not included by default but available from AppSource or developed using the Power BI Visuals SDK.
Example answer:
Custom visuals are visualizations available beyond the standard ones included in Power BI Desktop. They can be downloaded from Microsoft AppSource or built using the Power BI Visuals SDK for specific needs not met by default visuals.
19. What is VLOOKUP equivalent in Power BI?
Why you might get asked this:
Translates a common Excel task to Power BI, checking your knowledge of DAX or modeling alternatives.
How to answer:
Explain that relationships between tables (using Power Pivot) and the RELATED or LOOKUPVALUE DAX functions are used, not a direct VLOOKUP function.
Example answer:
Power BI doesn't have a direct VLOOKUP function like Excel. The equivalent is achieved primarily through creating relationships between tables in the data model. You can then use DAX functions like RELATED (within a calculated column) or LOOKUPVALUE to retrieve values from related tables.
20. What is an anti-join in Power BI?
Why you might get asked this:
Tests your advanced data transformation knowledge using Power Query merges.
How to answer:
Describe it as a type of merge in Power Query used to find rows in one table that do not have a match in another table based on a common column.
Example answer:
An anti-join (specifically, a Left Anti or Right Anti join in Power Query's Merge Queries) returns only those rows from one table that do not have a matching row in the other table. It's useful for finding discrepancies or unmatched records.
21. What is a data alert in Power BI?
Why you might get asked this:
Assesses your knowledge of monitoring features in the Power BI Service.
How to answer:
Explain data alerts as notifications triggered when data points on a dashboard tile cross a predefined threshold.
Example answer:
Data alerts are set up in the Power BI Service on dashboard tiles (specifically for KPIs, gauges, or cards). They send notifications (email or mobile) when the data displayed on the tile reaches a specific value or threshold you define, helping monitor critical metrics.
22. Compare star and snowflake schema.
Why you might get asked this:
This common power bi questions evaluates your understanding of data modeling best practices for analytical databases.
How to answer:
Define both schemas: Star (fact table centered, dimensions denormalized) and Snowflake (dimensions normalized). Mention their trade-offs (simplicity vs. storage/complexity).
Example answer:
A Star schema has a central fact table surrounded by denormalized dimension tables. It's simpler and often faster for querying. A Snowflake schema normalizes dimension tables further into sub-dimensions. It saves storage but increases query complexity due to more joins.
23. What are the differences between measures and columns?
Why you might get asked this:
A core DAX and modeling concept. This power bi questions tests your understanding of calculated values vs. physical data points.
How to answer:
Define Measures as calculations performed on the fly based on the filter context and Columns as calculations stored physically in the model or existing data.
Example answer:
Columns (calculated columns or imported columns) are static values for each row, computed during data refresh. Measures are dynamic calculations (aggregations like SUM, AVERAGE, COUNT) performed at query time based on the current filter context in the report visuals.
24. How do you share reports in Power BI?
Why you might get asked this:
Evaluates your knowledge of collaboration and distribution features in the Power BI Service.
How to answer:
List methods like publishing to the Service, using Workspaces, Apps, sharing links, embedding, or using Power BI Report Server.
Example answer:
Reports are typically shared via the Power BI Service. Methods include publishing from Desktop to a workspace, granting users access to the workspace, creating Power BI Apps, using the direct "Share" feature, embedding reports, or using Power BI Report Server for on-premises sharing.
25. What is the role of Power BI Report Server?
Why you might get asked this:
Tests your awareness of the on-premises deployment option for Power BI.
How to answer:
Explain it as the on-premises platform for hosting and managing Power BI reports, often used for organizations with strict data residency requirements.
Example answer:
Power BI Report Server is an on-premises server solution for publishing and managing Power BI reports and paginated reports. It's used by organizations that need to keep their data and reports within their own network infrastructure rather than in the cloud.
26. What are the unique features of Power BI over other BI tools?
Why you might get asked this:
Probes your knowledge of Power BI's competitive advantages.
How to answer:
Highlight its tight integration with Microsoft ecosystem, competitive pricing, user-friendly interface, and robust DAX engine.
Example answer:
Unique features include its seamless integration with other Microsoft products like Excel, Azure, and SQL Server, its attractive price point, a user-friendly interface that lowers the entry barrier, and the powerful, flexible DAX formula language for complex calculations.
27. How does Power BI differ from Tableau?
Why you might get asked this:
A common comparison power bi questions to understand your perspective on the BI landscape.
How to answer:
Compare them based on aspects like ease of use (subjective), integration (Microsoft ecosystem vs. broad), pricing, and data modeling/calculation approaches (DAX vs. Tableau's calculations).
Example answer:
Both are leading BI tools for data visualization. Power BI is deeply integrated with the Microsoft stack and known for its strong data modeling via Power Pivot and complex calculations with DAX. Tableau is often praised for its intuitive visualization interface and broader data source connectivity out-of-the-box. Pricing models also differ.
28. Can you export data from a Power BI report to other formats like SSRS?
Why you might get asked this:
Tests your understanding of data export limitations and capabilities within Power BI.
How to answer:
Explain that while direct export to SSRS report format isn't standard, data can be exported to common formats like Excel or CSV, which can then be used elsewhere.
Example answer:
You can export data from a Power BI visual or dataset to formats like Excel (.xlsx) or CSV (.csv). While you can't directly export to an SSRS report format, the exported data can certainly be used as a data source for an SSRS report.
29. What are the types of joins used in Power BI?
Why you might get asked this:
Assesses your understanding of combining data from different tables using Power Query.
How to answer:
List the common join types available in the Power Query 'Merge Queries' transformation (e.g., Inner, Left/Right Outer, Full Outer, Anti Joins, Cross Join).
Example answer:
In Power Query (Merge Queries), you can perform various joins: Inner (matching rows), Left Outer (all left rows, matching right), Right Outer (all right rows, matching left), Full Outer (all rows), Left Anti (rows only in Left), Right Anti (rows only in Right). Cross Join is also available in other contexts.
30. How do you maintain slicer and filter states across multiple pages in Power BI?
Why you might get asked this:
This practical power bi questions tests your ability to create a consistent user experience in multi-page reports.
How to answer:
Explain the "Sync slicers" feature and the concept of applying filters at the report level in the Filters pane.
Example answer:
You can use the "Sync slicers" feature to synchronize the state of a slicer across multiple report pages. Additionally, applying filters at the "All pages" or "This page" level in the Filters pane helps maintain consistent filtering contexts as users navigate the report.
Other Tips to Prepare for a power bi questions
Preparing effectively for power bi questions involves more than just memorizing definitions. Practice is key. Get hands-on experience by connecting to different data sources, cleaning messy data, building various data models, and writing complex DAX calculations. Create sample reports and dashboards showcasing diverse visualizations. Be ready to discuss projects you've worked on, explaining the challenges you faced and how you used Power BI to solve them. Quantify your impact whenever possible – did your report save time or uncover significant insights? As data expert Bill Schmarzo says, "Without data, you're just another person with an opinion." Demonstrating your ability to turn data into opinion-backed insights is crucial. Consider using tools like Verve AI Interview Copilot (https://vervecopilot.com) to practice answering power bi questions. This AI tool can simulate interview scenarios, provide feedback on your responses, and help you refine your communication skills, ensuring you're confident and articulate when discussing power bi questions. Leveraging Verve AI Interview Copilot can be a smart strategy to hone your answers and build confidence before the actual interview. Remember, every power bi questions is an opportunity to showcase your problem-solving skills and domain expertise.
Frequently Asked Questions
Q1: How long should I prepare for a Power BI interview?
A1: Preparation time varies, but focus on understanding core concepts and practicing common tasks for at least 1-2 weeks.
Q2: Should I build a portfolio for Power BI interviews?
A2: Yes, a portfolio of sample reports or dashboards is highly recommended to showcase your practical skills.
Q3: How important is DAX for Power BI interviews?
A3: Very important. Expect several power bi questions on DAX calculations, context transition, and common functions.
Q4: Will I be asked to write M code in the interview?
A4: Less common than DAX, but understanding basic Power Query transformation steps and the M language editor is beneficial.
Q5: How can I practice answering power bi questions effectively?
A5: Use online resources, mock interviews with peers, or AI tools like Verve AI Interview Copilot for targeted practice.
Q6: What's the difference between a report and a dashboard tile?
A6: Reports are multi-page interactive canvases, while dashboard tiles are single snapshots (visuals) from reports or Q&A, providing an overview.
