Introduction

Power BI has emerged as an industry-leading tool for business intelligence that allows organizations to analyse data, design interactive dashboards and take decisions based on data. As companies continue to use Power BI by 2025 there will be a demand for highly experts in Power BI is increasing.

To assist you in preparing in advance for that future Power BI interview We have put together an index of the most popular 10 Power BI interview questions and their answers. No matter if you’re an beginner or a professional These questions will assist you in understanding key Power BI concepts and demonstrate your knowledge efficiently.

1. What is Power BI, and why is it used?

Answer:

Power BI is an Business Intelligence (BI) as well as a data visualisation tool designed by Microsoft. It lets users connect to a variety of data sources and transform raw data and build interactive dashboards and reports.

Key Features of Power BI:

• Connects to various databases (SQL, Excel, Azure and more.)
• It provides drag-and-drop function for quick report creating
• Provides Artificial Intelligence-powered insight as well as advanced analytics
• Supports real-time data monitoring

2. What are the different components of Power BI?

Answer:

Power BI is comprised of three components:

1. The Power BI Desktop : A desktop program that allows you to create dashboards and reports.
2. Power BI Service : A cloud-based service that allows sharing as well as publishing data.
3. PowerBI Mobile : Mobile app for accessing dashboards while on the on the go.

Additional Components:

• Power BI Gateway : Connects cloud services to existing data sources.
• Power BI Embedded : Allows embedding reports into custom applications.
• Power Query : A tool to perform clean and transform data.

3. What is the difference between Power BI and Tableau?

Feature	power BI	Tableau
Usability	User-friendly, drag-and-drop	Further advanced, it requires a degree.
Pricing	Cost-effective (Microsoft Suite)	More expensive
Integration	The best for Microsoft products	Works with a variety of platforms.
Data Handling	Small to medium-sized data sets are handled effectively	Manages large data sets efficiently
Visualization	It’s strong, but Tableau provides more flexibility	Best-in-class visualization

Key Insights :  If your business employs Microsoft tools such as Excel, Azure, or SQL Server, Power BI is an excellent choice.

4. Explain DAX in Power BI. Why is it important?

Answer:

DAX ( Data Analysis Expressions) is formula language used by Power BI to perform calculations and manipulate data. It’s like Excel formulas but more efficient in dealing with complex data relations.

Why is DAX Important?

• It assists in creating measured measurements and columns.
• Allows for complex aggregations and calculations based on time
• Enhances data modeling capabilities

An Example DAX Formula

To determine the Total Sales to calculate Total Sales, you can use:

TotalSales = SUM(Sales[Revenue])

This formula adds what is in the Sales column of the Sales table.

5. What are Measures and Calculated Columns in Power BI?

Answer:

Feature	Measures	Calculated Columns
Definition	Performs dynamic calculations on the fly	Creates a new column that has pre-calculated values
Storage	Not stored, but calculated in real-time	Data model is stored in the data model.
Example	Total Sales = SUM(Sales[Revenue])	Discount Price = Sales[Price] * 0.9
Performance	More efficient	Consumes more memory

6. What are Power BI Filters, and how do they work?

Answer:

Power BI provides various types of filters to control and refine transparency of reports.

Types of Filters available in Power BI

• Visual-Level Filters : Apply to a specific visual.
• Page-Level Filters : Can affect all images on a particular page.
• Report-Level Filters :  Affect every page of the report.
• Drillthrough Filters : Concentrate on specific aspects for a thorough analysis.

7. What is Power Query, and how is it used?

Answer:

Power Query is a data transformation tool within Power BI which assists in:

• Extracting information from a variety of sources
• Transformation and cleansing the raw data
• Loading transformed data to Power BI

8. How do relationships work in Power BI?

Answer:

Power BI allows creating connections between tables with Foreign and Primary Keys.

Different types of relationships

• One-to-One (1:1) – Each record in Table A corresponds to one record from Table B.
• One-to-Many (1:M) – A record in Table A is matched to multiple records from Table B.
• Many-to-Many (M:M) – Both tables have values that overlap.

Example:
Customers Table (CustomerID) and Orders Table Customer Table (CustomerID) as well as an The Orders Table (CustomerID) are the same relationship that is a One-to-Many relationship.

9. What is Row-Level Security (RLS) in Power BI?

Answer:

Row-Level Security (RLS) in Power BI blocks access to data according to the user’s role. It assists in:
– The control of who has access to specific information
– Improved the security of data and ensuring compliance
– Reduce the need for numerous reports

10. How to optimize Power BI reports for better performance?

Answer:

To increase the performance of Power BI be sure to follow these top methods:

• Reduce data load : Eliminate unnecessary rows and columns.
• Enhance the DAX measures :  Utilize FILTER, SUMX and CALCULATE to the best of their abilities.
• Enable query folding : Transform data at the level of the database.
• Utilize Aggregations : Calculate values in advance instead of doing it in-the-moment.
• Limit the number of visuals displayed on Dashboard : The use of too many images slow down reports.

Conclusion

Power BI is an powerful tool for business intelligence that allows data-driven decision-making. The preparation for an Power BI interview in 2025 will require an in-depth knowledge of the DAX model, data modeling, visualization, and optimization for performance. Power bi training online helps professionals build the skills needed to analyze data and create insightful visualizations.

If you can master this the top 10 Power BI interview questions and answers you’ll be able to impress employers and get the ideal career within data analysis. Enhance your skills with Data Science & BI Certification Courses.