Power BI Interview Questions – Set 02

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What is Power BI Desktop?

Power BI Desktop is a free desktop application which can be installed on your computers. Power BI Desktop works with the Power BI service by providing advanced data exploration, shaping, modeling, and creating a report with highly interactive visualizations. You can save the work to a file or publish your data and reports right to the Power BI site to share with others.

What is power Pivot data table?

Power Pivot data table is a model which is made up of tables, data types, columns, and table relations. These data tables are constructed for holding the data for a business entity.

How is data security implemented in Power BI?

Power BI applies the row-level security role to models:

  • A DAX expression is used on a table, filtering its rows at the query time.
  • Dynamic security involves the use of USERNAME functions in security role definitions.
  • A table is created in the model which relates users to specific dimensions and a role.

What are the significant components of Power BI?

  1. Power Pivot: Power pivot is used in data modeling for in-memory analytics and loads on the Power Query.
  2. Power Query: It is used to access, search, and transform public and internal data sources.
  3. Power View: By using the power view, you can analyze, visualize, and display the data as an interactive data visualization.
  4. Power Map: It brings the data to life with interactive geographical visualization.
  5. Power Q&A: You can ask any questions and get an immediate response with the natural language query.

What is Power Query?

Power query is an ETL tool which is used to shape, clean, and transform data using intuitive interfaces without having to use coding. It helps the user to:

  • Import the data from a wide range of sources from files, big data, databases, and social media data, etc.
  • Join and append the data from multiple data sources.
  • Shape the data as per requirement by adding and removing the data.

What is Power BI Publisher for Excel?

You can use Power BI publisher for Excel to pivot tables, pin ranges, and charts to Power BI.

  • The user manages the tiles such as remove them, refresh them, in Excel.
  • Pinned items must be removed from the dashboard in the service (removing in Excel only deletes the connection).
  • The Power BI Publisher for Excel is also used to connect from Excel to datasets which are hosted in the Power BI Service.
  • An Excel pivot table is generated with a connection (ODC file) to the data in Azure.

The Publisher installs all necessary drivers on the local machine to establish connectivity.

What are the features of Power BI?

  • It allows us to transform data into visuals.
  • It allows us to explore and analyze the data from all sources.
  • It allows us to scale across organizations with built-in governance and security.
  • Once an output is generated, users can display the same on multiple devices that are compatible with the Power BI application.
  • With Power BI natural language processing or Power BI Q&A, users can perform queries on reports using simple English words.

What is query folding in Power Query?

Query folding is when steps defined in Power Query or Query Editor are translated into SQL and executed by the source database rather than the client machine. It is important to processing performance and scalability, given limited resources on the client machine.

What are the Power BI dataset, Report, and Dashboard?

Dataset: The source is used to create reports and tiles or visuals.

  • A data model (local to PBIX or XLSX) in an Analysis Services Server
  • Data could be inside of model or a Direct Query connection to a source.

Report: An individual Power BI Desktop file (PBIX) containing one or more report pages.

  • It is built for deep, interactive analysis experience for a given dataset (filters, formatting).
  • Each Report is connected to at least one dataset
  • Each page is containing one or more visuals or tiles.

Dashboard: A collection of visuals from different reports and, optionally, a pinned.

  • It is built to aggregate primary visuals and metrics from multiple datasets.

What are the versions of Power BI?

Power BI brings a lot of flexibility when it comes to data reporting and visualization. That?s why Power BI has been divided into three versions.

  • Power BI Desktop: This is the on-premise for window 10.
  • Power BI Service: This is for publishing to the cloud.
  • Mobile Power BI: This is for mobile users.