Preparing for a Power BI interview requires a solid understanding of data modeling, DAX, visualization, and report optimization. Our guide to Power BI interview questions and answers is designed to help you crack any interview with confidence. From basic concepts to advanced problem-solving, you’ll find practical explanations that demonstrate both knowledge and hands-on skills. Whether you are a beginner or an experienced professional, mastering these topics will give you a competitive edge. To strengthen your expertise further, enrolling in a structured Power BI course can provide real-world insights and prepare you for career growth.
Power BI Basics & Fundamentals
1. What is Power BI, and how does it differ from Excel?
How to answer: Provide a clear definition, the context of use in Power BI, and best practices.
Example: For instance, when asked ‘What is Power BI and how does it differ from Excel?’, you might explain it using a business scenario, e.g., ‘In a sales dashboard, I used this feature tox…’.
2. Difference between Power BI Desktop and Power BI Service?
How to answer: Provide a clear definition, the context of use in Power BI, and best practices.
Example: For instance, when asked ‘Difference between Power BI Desktop and Power BI Service?’, you might explain it using a business scenario, e.g., ‘In a sales dashboard, I used this feature to…’.
3. What are Power BI Dataflows?
How to answer: Provide a clear definition, the context of use in Power BI, and best practices.
Example: For instance, when asked ‘What are Power BI Dataflows?’, you might explain it using a business scenario, e.g., ‘In a sales dashboard, I used this feature to…’.
4. What is a Dataset in Power BI?
How to answer: Provide a clear definition, the context of use in Power BI, and best practices.
Example: For instance, when asked ‘What is a Dataset in Power BI?’, you might explain it using a business scenario, e.g., ‘In a sales dashboard, I used this feature to…’.
5. Explain the difference between Report and Dashboard in Power BI.
How to answer: Provide a clear definition, the context of use in Power BI, and best practices.
Example: For instance, when asked ‘Explain the difference between Report and Dashboard in Power BI.’, you might explain it using a business scenario, e.g., ‘In a sales dashboard, I used this feature to…’.
6. What are the different types of filters in Power BI?
How to answer: Provide a clear definition, the context of use in Power BI, and best practices.
Example: For instance, when asked ‘What are the different types of filters in Power BI?’, you might explain it using a business scenario, e.g., ‘In a sales dashboard, I used this feature to…’.
7. What are calculated columns vs. measures?
How to answer: Provide a clear definition, the context of use in Power BI, and best practices.
Example: For instance, when asked ‘What are calculated columns vs. measures?’, you might explain it using a business scenario, e.g., ‘In a sales dashboard, I used this feature to…’.
8. What licensing options does Power BI offer?
How to answer: Provide a clear definition, the context of use in Power BI, and best practices.
Example: For instance, when asked ‘What licensing options does Power BI offer?’, you might explain it using a business scenario, e.g., ‘In a sales dashboard, I used this feature to…’.
Data Sources & Power Query
9. How do you connect Power BI to SQL Server?
How to answer: Provide a clear definition, the context of use in Power BI, and best practices.
Example: For instance, when asked ‘How do you connect Power BI to SQL Server?’, you might explain it using a business scenario, e.g., ‘In a sales dashboard, I used this feature to…’.
10. Difference between DirectQuery and Import mode?
How to answer: Provide a clear definition, the context of use in Power BI, and best practices.
Example: For instance, when asked ‘Difference between DirectQuery and Import mode?’, you might explain it using a business scenario, e.g., ‘In a sales dashboard, I used this feature to…’.
11. What is Composite Mode in Power BI?
How to answer: Provide a clear definition, the context of use in Power BI, and best practices.
Example: For instance, when asked ‘What is Composite Mode in Power BI?’, you might explain it using a business scenario, e.g., ‘In a sales dashboard, I used this feature to…’.
12. How do you handle null values in Power Query?
How to answer: Provide a clear definition, the context of use in Power BI, and best practices.
Example: For instance, when asked ‘How do you handle null values in Power Query?’, you might explain it using a business scenario, e.g., ‘In a sales dashboard, I used this feature to…’.
13. What are query parameters in Power BI?
How to answer: Provide a clear definition, the context of use in Power BI, and best practices.
Example: For instance, when asked ‘What are query parameters in Power BI?’, you might explain it using a business scenario, e.g., ‘In a sales dashboard, I used this feature to…’.
14. Explain the difference between Merge Queries and Append Queries.
How to answer: Provide a clear definition, the context of use in Power BI, and best practices.
Example: For instance, when asked ‘Explain the difference between Merge Queries and Append Queries.’, you might explain it using a business scenario, e.g., ‘In a sales dashboard, I used this feature to…’.
15. How do you remove duplicates in Power Query?
How to answer: Provide a clear definition, the context of use in Power BI, and best practices.
Example: For instance, when asked ‘How do you remove duplicates in Power Query?’, you might explain it using a business scenario, e.g., ‘In a sales dashboard, I used this feature to…’.
16. What is the role of M language in Power Query?
How to answer: Provide a clear definition, the context of use in Power BI, and best practices.
Example: For instance, when asked ‘What is the role of M language in Power Query?’, you might explain it using a business scenario, e.g., ‘In a sales dashboard, I used this feature to…’.
17. How do you schedule data refresh in Power BI Service?
How to answer: Provide a clear definition, the context of use in Power BI, and best practices.
Example: For instance, when asked ‘How do you schedule data refresh in Power BI Service?’, you might explain it using a business scenario, e.g., ‘In a sales dashboard, I used this feature to…’.
18. What are Gateway types in Power BI?
How to answer: Provide a clear definition, the context of use in Power BI, and best practices.
Example: For instance, when asked ‘What are Gateway types in Power BI?’, you might explain it using a business scenario, e.g., ‘In a sales dashboard, I used this feature to…’.
Data Modeling & Relationships
19. What is Star Schema vs. Snowflake Schema in Power BI?
How to answer: Provide a clear definition, the context of use in Power BI, and best practices.
Example: For instance, when asked ‘What is Star Schema vs. Snowflake Schema in Power BI?’, you might explain it using a business scenario, e.g., ‘In a sales dashboard, I used this feature to…’.
20. What is a relationship in Power BI and how do you define it?
How to answer: Provide a clear definition, the context of use in Power BI, and best practices.
Example: For instance, when asked ‘What is a relationship in Power BI and how do you define it?’, you might explain it using a business scenario, e.g., ‘In a sales dashboard, I used this feature to…’.
21. What are Cardinality and Cross Filter Direction in Power BI relationships?
How to answer: Provide a clear definition, the context of use in Power BI, and best practices.
Example: For instance, when asked ‘What are Cardinality and Cross Filter Direction in Power BI relationships?’, you might explain it using a business scenario, e.g., ‘In a sales dashboard, I used this feature to…’.
22. What is the difference between a fact table and a dimension table?
How to answer: Provide a clear definition, the context of use in Power BI, and best practices.
Example: For instance, when asked ‘What is the difference between a fact table and a dimension table?’, you might explain it using a business scenario, e.g., ‘In a sales dashboard, I used this feature to…’.
23. What is a surrogate key in data modeling?
How to answer: Provide a clear definition, the context of use in Power BI, and best practices.
Example: For instance, when asked ‘What is a surrogate key in data modeling?’, you might explain it using a business scenario, e.g., ‘In a sales dashboard, I used this feature to…’.
24. How do you handle many-to-many relationships in Power BI?
How to answer: Provide a clear definition, the context of use in Power BI, and best practices.
Example: For instance, when asked ‘How do you handle many-to-many relationships in Power BI?’, you might explain it using a business scenario, e.g., ‘In a sales dashboard, I used this feature to…’.
25. What are hierarchies in Power BI?
How to answer: Provide a clear definition, the context of use in Power BI, and best practices.
Example: For instance, when asked ‘What are hierarchies in Power BI?’, you might explain it using a business scenario, e.g., ‘In a sales dashboard, I used this feature to…’.
26. What is row-level security (RLS) in Power BI?
How to answer: Provide a clear definition, the context of use in Power BI, and best practices.
Example: For instance, when asked ‘What is row-level security (RLS) in Power BI?’, you might explain it using a business scenario, e.g., ‘In a sales dashboard, I used this feature to…’.
27. What is object-level security (OLS)?
How to answer: Provide a clear definition, the context of use in Power BI, and best practices.
Example: For instance, when asked ‘What is object-level security (OLS)?’, you might explain it using a business scenario, e.g., ‘In a sales dashboard, I used this feature to…’.
28. How do you optimize a data model for performance in Power BI?
How to answer: Provide a clear definition, the context of use in Power BI, and best practices.
Example: For instance, when asked ‘How do you optimize a data model for performance in Power BI?’, you might explain it using a business scenario, e.g., ‘In a sales dashboard, I used this feature to…’.
DAX & Calculations
29. What is DAX and why is it important in Power BI?
How to answer: Define DAX as a formula language for Power BI, used for calculations and data analysis.
Example: I used DAX to create a Year-to-Date sales measure that updated dynamically with user selections.
30. Difference between SUM and SUMX in DAX?
How to answer: SUM adds column values; SUMX iterates over a table and applies an expression.
Example: I used SUMX to calculate total revenue by multiplying price and quantity for each row before summing.
31. What is the difference between CALCULATE and CALCULATETABLE?
How to answer: CALCULATE returns a single value with modified filters, CALCULATETABLE returns a table.
Example: I used CALCULATETABLE to create a table of top-selling products filtered by region.
32. Explain the concept of filter context and row context.
How to answer: Filter context comes from slicers/filters; row context exists inside calculated columns or iterators.
Example: In a sales measure, the filter context changed results when selecting specific regions.
33. What is RELATED and RELATEDTABLE in DAX?
How to Answer: RELATED brings values from a related table in a one-to-one or many-to-one relationship; RELATEDTABLE returns a table of related rows.
Example: I used RELATED to bring product category names into a sales table.
34. When would you use EARLIER in DAX?
How to Answer: EARLIER is used to access a value from an earlier row context, often in calculated columns.
Example: I calculated rank within each category by referencing EARLIER category values.
35. What are time intelligence functions in DAX?
How to Answer: Functions like TOTALYTD, SAMEPERIODLASTYEAR, and DATESBETWEEN help analyze time-based data.
Example: I compared current sales with last year using SAMEPERIODLASTYEAR.
36. How do you handle dynamic titles in Power BI using DAX?
How to Answer: Use a measure returning a text value that updates with filters.
Example: My “Sales Report for [Selected Year]” title changed based on slicer selection.
37. What is the difference between ALL and ALLEXCEPT?
How to Answer: ALL removes all filters from a table; ALLEXCEPT removes filters except those specified.
Example: I used ALLEXCEPT to keep region filters while ignoring product filters.
38. What is the difference between variables and constants in DAX?
How to Answer: Variables are reusable temporary values; constants are fixed values.
Example: I stored intermediate calculations in variables to improve measure performance.
39. How do you optimize DAX performance?
How to Answer: Use variables, reduce row context transitions, and minimize nested iterators.
Example: I replaced complex nested FILTERs with variables, cutting refresh time in half.
40. What is the difference between DISTINCT and VALUES?
How to Answer: DISTINCT returns unique values; VALUES returns unique values plus a blank if applicable.
Example: VALUES was needed to include blank categories in a slicer.
41. How do you create running totals in DAX?
How to Answer: Use CALCULATE with FILTER and ALLSELECTED to accumulate over time.
Example: My running sales total updated as users applied date filters.
42. What are KPI indicators in DAX?
How to Answer: KPIs combine actual, target, and trend indicators for performance tracking.
Example: I built a KPI to show sales against monthly targets with green/yellow/red status.
Visualizations & Reports
43. What are custom visuals in Power BI?
How to Answer: Custom visuals are third-party or community-developed visuals that extend Power BI’s default set.
Example: I imported a bullet chart visual from AppSource to show progress against targets.
44. How do you use bookmarks in Power BI?
How to Answer: Bookmarks capture report states (filters, visuals, selection) for easy navigation or storytelling.
Example: I created bookmarks for “Executive Summary” and “Detailed View” to let users toggle perspectives.
45. Difference between slicers and filters?
How to Answer: Slicers are visual filter elements on the canvas; filters are set in the filter pane or behind the scenes.
Example: I used slicers for user-friendly region selection while keeping filters for security-based restrictions.
46. What are drillthrough pages?
How to Answer: Drillthrough pages allow users to right-click data points to see detailed context.
Example: Clicking a customer name opened a detailed purchase history drillthrough page.
47. What is report tooltip and how to customize it?
How to Answer: A tooltip appears when hovering over visuals; it can be customized with fields or separate pages.
Example: I designed a tooltip page showing quarterly trends when hovering over a bar chart.
48. What is conditional formatting in Power BI visuals?
How to Answer: It changes color, icons, or data bars based on field values.
Example: Sales above target showed as green, below target as red.
49. How do you create hierarchical visuals?
How to Answer: Use hierarchy fields or drill-down capabilities in visuals.
Example: I built a geography hierarchy with Country → State → City drill-down.
50. What is a decomposition tree in Power BI?
How to Answer: It breaks down metrics into contributing factors dynamically.
Example: I analyzed sales decline by drilling into region, product, and salesperson levels.
51. What is a Q&A visual?
How to Answer: It lets users type natural language questions to generate visuals automatically.
Example: Typing “total sales by category” generated a column chart instantly.
52. How do you implement dynamic axis in visuals?
How to Answer: Use disconnected tables and measures to switch axis values.
Example: I let users toggle between “Sales by Product” and “Sales by Region” on the same chart.
53. What is small multiples in Power BI?
How to Answer: A visual repeated across categories for easy comparison.
Example: Monthly sales trends were displayed side-by-side for each region.
Example: Monthly sales trends were displayed side-by-side for each region.
54. How do you optimize visuals for performance?
How to Answer: Limit visuals per page, reduce high-cardinality data, and avoid unnecessary complex measures.
Example: Reducing from 20 visuals to 8 sped up load time by 40%.
55. How do you use themes in Power BI reports?
How to Answer: Themes control colors, fonts, and visual styles consistently.
Example: I applied corporate brand colors to all visuals for a consistent look.
Performance Optimization
56. What are best practices for Power BI performance optimization?
How to Answer: Optimize data model size, reduce DAX complexity, and use aggregations.
Example: I improved report refresh speed by summarizing transaction data into monthly aggregates.
57. How do you reduce dataset size?
How to Answer: Remove unused columns, filter unnecessary rows, and use proper data types.
Example: Removing redundant columns reduced dataset size from 1GB to 400MB.
58. What is aggregations table in Power BI?
How to Answer: Pre-calculated summary tables that speed up queries.
Example: I created an aggregation table of daily totals to improve visual response time.
59. How do you monitor performance using Performance Analyzer?
How to Answer: Performance Analyzer logs render times for visuals and queries.
Example: I identified a slow measure and optimized its DAX logic.
60. What are the best practices for DirectQuery performance?
How to Answer: Minimize visuals, use filters, optimize source queries, and aggregate in the source.
Example: I added SQL indexes to speed up DirectQuery dashboards.
61. How do you optimize visuals to reduce rendering time?
How to Answer: Limit complex visuals, pre-aggregate data, and reduce high-cardinality categories.
Example: Grouping customers into segments sped up visuals significantly.
62. What is incremental refresh and when to use it?
How to Answer: Refreshes only new or changed data, not the entire dataset.
Example: Monthly incremental refresh cut refresh time from 2 hours to 15 minutes.
63. How do you handle large datasets in Power BI?
How to Answer: Use aggregations, incremental refresh, and hybrid models.
Example: I split data into recent detailed data and older aggregated data for performance.
Power BI Service & Sharing
64. What is Power BI Service?
How to Answer: A cloud platform for hosting, sharing, and collaborating on Power BI reports.
Example: I published reports to the service so stakeholders could access them via browser.
65. How do you publish reports to Power BI Service?
How to Answer: From Power BI Desktop, use the Publish option to send to a workspace.
Example: I published a monthly performance report for the sales team.
66. What are workspaces in Power BI?
How to Answer: Collaborative areas in the service to manage reports, datasets, and dashboards.
Example: We used a marketing workspace for all campaign analytics.
67. Difference between My Workspace and App Workspaces?
How to Answer: My Workspace is personal; App Workspaces are shared.
Example: I built reports in an App Workspace for team-wide access.
68. What are Power BI Apps?
How to Answer: Packaged collections of dashboards and reports published from a workspace.
Example: We released a Finance App for executives with curated reports.
69. How do you schedule data refresh in Power BI Service?
How to Answer: Configure refresh settings in the dataset’s schedule tab.
Example: I set a daily 6 AM refresh for up-to-date metrics.
70. What are data gateways in Power BI?
How to Answer: Gateways enable secure connection to on-premises data sources.
Example: I installed a gateway to refresh reports using our local SQL Server.
71. How do you share reports securely?
How to Answer: Share with specific users/groups, enable RLS, and manage permissions.
Example: Only managers could view department-level sales data.
72. What is export and subscription in Power BI Service?
How to Answer: Export downloads reports; subscriptions send snapshots via email.
Example: Executives received a weekly PDF snapshot via subscription.
Security & Governance
73. What is Row-Level Security (RLS) in Power BI?
How to Answer: Restricts data access for users based on filters applied to roles.
Example: Regional managers only see sales for their own region.
74. How do you implement RLS?
How to Answer: Define roles and DAX filters in Power BI Desktop, then publish and assign users.
Example: Created an RLS role filtering data where [Region] = USERPRINCIPALNAME().
75. Difference between static RLS and dynamic RLS?
How to Answer: Static uses fixed filters; dynamic adjusts filters based on the logged-in user.
Example: Dynamic RLS pulled region info from a user mapping table.
76. What is Object-Level Security (OLS)?
How to Answer: Restricts visibility of specific tables or columns.
Example: Hiding salary columns from non-HR roles.
77. How do you audit user activity in Power BI?
How to Answer: Use audit logs and activity reports in the admin portal.
Example: Checked who viewed sensitive reports during a compliance review.
78. What is sensitivity labeling in Power BI?
How to Answer: Labels classify and protect sensitive data.
Example: Labeled HR reports as “Confidential” to restrict export.
79. How do you manage governance in Power BI?
How to Answer: Set policies for data sources, workspace naming, and access control.
Example: Implemented naming conventions and approval workflows for new datasets.
80. How do you handle compliance in Power BI?
How to Answer: Follow GDPR, HIPAA, or other regulations with proper masking and RLS.
Example: Masked customer PII before publishing reports.
Power BI in Enterprise & Integration
81. How do you integrate Power BI with SharePoint?
How to Answer: Embed reports using the “Embed in SharePoint Online” option.
Example: Embedded a project dashboard into the team’s SharePoint site.
82. How do you embed Power BI in a website?
How to Answer: Use publish-to-web (public) or secure embed (authenticated) options.
Example: Embedded a secure KPI report on an internal portal.
83. What is Power BI Embedded?
How to Answer: Azure service to embed Power BI visuals in apps with custom authentication.
Example: Integrated dashboards into a customer-facing SaaS platform.
84. How do you integrate Power BI with Teams?
How to answer: Use the Power BI app in Teams or embed tabs with reports.
Example: Added sales reports as a Teams tab for easy access.
85. How do you connect Power BI with Azure Synapse?
How to answer: Connect via DirectQuery or Import using Synapse SQL endpoints.
Example: Built near real-time analytics dashboards from Synapse data.
86. How do you connect Power BI with Dataverse?
How to answer: Use the Dataverse connector to pull Power Apps data.
Example: Combined CRM data from Dataverse with marketing spend.
87. How do you integrate Power BI with Excel?
How to answer: Export to Excel, use Analyze in Excel, or connect Excel to datasets.
Example: Finance used Analyze in Excel to drill into Power BI datasets.
88. What is the role of Power BI in enterprise analytics?
How to answer: Provides unified, self-service BI across departments.
Example: Consolidated multiple departmental reports into a single enterprise dashboard.
Deployment, CI/CD, and Automation
89. How do you implement deployment pipelines in Power BI?
How to answer: Use pipelines in the Power BI Service to manage dev, test, and prod stages.
Example: Deployed updated visuals to test before production release.
90. What are the stages in a Power BI deployment pipeline?
How to answer: Development → Test → Production.
Example: Validated report filters in the test stage before publishing live.
91. How do you automate dataset refresh using PowerShell?
How to answer: Use Power BI REST API with PowerShell scripts.
Example: Automated refresh triggered after nightly ETL completion.
92. How do you manage version control in Power BI?
How to answer: Use PBIX files in source control or deployment pipelines.
Example: Stored PBIX files in GitHub for change tracking.
93. What is API integration in Power BI?
How to answer: Use Power BI REST API to embed, refresh, or manage content programmatically.
Example: Automatically published monthly reports via API calls.
AI, Advanced Analytics & New Features
94. How do you use AI visuals in Power BI?
How to answer: Use Key Influencers, Decomposition Tree, and Q&A visuals.
Example: Key Influencers showed that discount percentage strongly affected sales.
95. What is Cognitive Services integration in Power BI?
How to answer: Connect Azure Cognitive Services for text analytics or sentiment scoring.
Example: Analyzed customer reviews for sentiment within Power BI.
96. What are smart narratives in Power BI?
How to answer: Automatically generate textual summaries of visuals.
Example: Smart narratives summarized monthly sales trends for executives.
97. What are the latest Power BI 2025 updates you should know?
How to answer: Mention new features like Fabric integration, enhanced DirectLake, or AI Copilot.
Example: Used AI Copilot to generate DAX measures automatically.
Interview Curveballs & Scenario Questions
98. Describe a situation where a DAX calculation gave wrong results. How did you fix it?
How to answer: Explain debugging steps and the fix.
Example: Fixed a running total issue by replacing ALL with ALLSELECTED to respect slicers.
99. How would you troubleshoot a slow Power BI report in production?
How to answer: Check Performance Analyzer, DAX complexity, model size, and source queries.
Example: Reduced visuals and optimized a heavy measure to cut load time by 60%.
100. You need to combine data from on-prem SQL and cloud API in Power BI. How would you approach it?
How to answer: Use data gateway for on-prem SQL and connector for API, then merge in Power Query.
Example: Merged SQL sales data with API-based inventory levels for a single report.
