Power BI Interview Questions and Answers-Credo systemz.pdf
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- 2. Page 2 1. What is Power BI? Power BI is a suite of business analytics tools to analyze data and share insights. To create meaningful reports and dashboards, Power BI provides a variety of: Data connectors, Data transformation tools, Visualization options. 2. How do you connect to data sources in Power BI? Power BI provides a variety of connectors for connecting to different data sources, including Excel files, SQL Server databases, Azure services, and many others. To connect to a data source, select the appropriate connector and select the tables or data to import. 3. What are the different components of Power BI? Power BI consists of several components which have specific functions related to data transformation, modeling, and visualization. The Components of Power BI, Power Query, Power Pivot, Power View, Power Map, Power BI Desktop. 4. What is DAX and how is it used in Power BI? Data Analysis Expressions is a formula language to create custom calculations in Power BI. It is used in measures, calculated columns, and calculated tables. DAX allows to create Complex calculations, Hierarchical structures. 5. What are the best practices for creating effective Power BI reports? The few best practices for creating effective Power BI reports are: Start with a clear objective and audience, Select the right visuals for the data being presented, Using appropriate color schemes and font sizes, Ensure the report is easy to navigate and interact with.
- 3. Page 3 6. How do you create a report in Power BI? To create a Power BI report, first import the data to analyze then create visualizations. Use the drag-and-drop interface in Power BI Desktop. After creating visualizations, Add them to a report page and customize the layout, formatting, and interactivity as needed. 7. How do you share a Power BI report with others? Power BI reports can be shared with others in a variety of ways: Publishing to the Power BI service, Embedding in other applications: Access to the report can be controlled through permissions and security settings in Power BI. 8. How would you use Power Query to transform data from multiple tables into a single fact table? To transform data from multiple tables into a single fact table, use Power Query to perform the following steps: Import the tables into Power BI and create relationships between them. Use the Power Query Merge Queries option to combine the related tables into a single table. Use the Group By option to aggregate the data. Use the Pivot option to reshape the data into a flat format. 9. What are the steps required to optimize the Power BI report performance? To optimize the Power BI report performance with large data, use the following techniques: Import data into Power BI using DirectQuery Use the Query Reduction feature in Power Query Use the Import or DirectQuery mode to reduce the number of calculations Use the incremental refresh option to limit the amount of data 10. How would you use Power BI to create a drill-through report?
- 4. Page 4 To create a drill-through report in Power BI, these steps are required, Create a summary report with high-level data. Create a detailed report along with underlying data. Create a button or visual in the summary report to access the detailed report. Set up a filter in the detailed report Use the Drillthrough feature in Power BI 11. How would you use DAX to create a dynamic calculation that adjusts based on user selections? To create a dynamic calculation in DAX, Use the following steps: Create a measure to use a SWITCH function to evaluate user selections. Use a slicer or a filter to select the variables used in the SWITCH function. Use a disconnected table to create a list of options to select from. Use a SELECTEDVALUE function to retrieve the user selection 12. How to use Power BI for creating a dynamic visual? Power BI is used to create a dynamic visual using the below steps: Use a DAX formula to create the measure and calculate the value to be displayed in the visual. Use a slicer or a filter to select the variables used in the DAX formula. Use the Visual Level Filters feature in Power BI to apply the slicer or filter. Use the Sync Slicers feature in Power BI to synchronize the slicer or filter across multiple visuals. 13. State the uses of Power BI? The important uses of Power BI are: Power BI is used to analyze sales and marketing data. It helps to identify trends and opportunities for growth. To track key performance indicators, power BI allows to create financial reports and dashboards. Power BI assures monitoring operational data in real-time to identify potential issues. Sharing data and insights with team members using interactive reports,dashboards by Power BI. Power BI can combine data from multiple sources. 14. What is self service BI? Self-service BI refers to a process in which business users are empowered to create their own reports and analysis. This approach is
- 5. Page 5 useful to: Access and analyze data in real-time, Better decisions, Gain insights to better business outcomes. Self-service BI tools like Power BI, Tableau, and QlikView provide an intuitive user interface. It helps to connect to data sources, manipulate data, create reports, visualizations, and share with others. 15. Mention the Power BI versions? The various versions of Power BI are: Power BI Desktop - free, downloadable application for Windows. Power BI Pro - Paid version of Power BI with additional features like data collaboration and sharing capabilities. Power BI Premium - Advanced version of Power BI with additional features such as increased data capacity and higher refresh rates. Power BI Mobile - Mobile app for iOS and Android devices. Power BI Report Server - On-premises solution for creating, publishing and managing Power BI reports. 16. What are the advantages of Power BI? The Advantages of Power BI are: Data visualization: Power BI allows you to create dynamic and interactive data visualizations. Integration with various data sources: Power BI can connect to a wide range of data sources. Self-service BI: Power BI allows users to create their own reports and analysis. Collaboration: Power BI helps share reports and dashboards with others. Security: Power BI offers robust security features to secure the sensitive data. Cost-effective: Power BI offers a range of pricing options. 17. What is Power pivot? Power Pivot is a data modeling tool used to Create complex data models Perform powerful data analysis Create relationships between data from different sources Perform data analysis and aggregation Import large data sets from multiple sources. 18. State the key features of Power BI
- 6. Page 6 Key features of Power BI: Data connectivity: Power BI Desktop allows to connect to a wide range of data sources and cloud-based sources. Use the Query Editor to perform Data transformation. Data modeling: Power BI is used to create relationships between tables and create calculated columns and measures. Power BI Desktop offers a range of visualization types, including charts, tables, maps, and custom visualizations. Users can create interactive reports with drill-down functionality and filters to allow for exploration of data. Reports can be shared with others through the Power BI service. 19. What is Power BI Query Editor? Power BI Query Editor is a powerful tool within Power BI Desktop. It is used to clean, shape, and transform the data. It is a valuable tool to create powerful visualizations and reports for Business analysts, Data analysts, To work with data. 20. Mention the different visualizations available in Power BI? Power BI offers a wide range of visualizations to represent data in an interactive and meaningful way. Column chart, Bar chart Line chart, Area chart Pie chart, Donut chart Scatter chart, Bubble chart Map chart, Gauge chart 21. State about the language used in Power Query M is a functional programming language used to define data transformations in Power Query. It allows the creation of custom functions and expressions to manipulate and transform data. M is a powerful language to perform complex data transformations. 22. What is Power BI Designer? Power BI Designer is a desktop-based application to create and publish Power BI reports. It is a standalone application to be downloaded and installed on a Windows-based machine. It is designed to provide a simplified experience for creating and editing Power BI reports.
- 7. Page 7 23. What are the important features of Power BI? The important features of Power BI are: Data modeling and transformation Data visualization Data exploration Collaboration Mobile accessibility Integration with other tools 24. Mention some applications of Power BI? Applications of Power BI are: To track sales performance, marketing campaigns, customer segmentation, and other key metrics. Analyze financial data, including revenue, expenses, profit margins, cash flow, and other financial metrics. Tracking inventory levels, shipping times, delivery performance, and other key metrics in the supply chain. To perform HR Analytics to improve employee engagement, retention, and productivity. Analyze patient data, clinical outcomes, and healthcare costs to improve healthcare quality. Track student performance, enrollment trends, and other key metrics in education. 25. What is Power BI Services? Power BI Services is a cloud-based business analytics service to easily create and share dashboards and reports. It offers several features to collaborate on reports and visualizations like: Data Sharing Collaboration Data Refresh Security Mobile Access Custom Visualizations