PowerBI Interview questions 2023
Advantages of Power BI
- helps build interactive visualizations. - Allows users to transform data into visualizations. - Provides quick and accurate solutions. - Allows non-technical employees to quickly gain insights
Name the different connectivity modes available in Power BI?
1)SQL Server Import: Full capabilities of the Power BI Desktop. 2) Direct Query : Only stores the metadata of the underlying data and not the actual data. 3) Live Connection: Does not store data in the Power BI model. Directly queries the existing Analysis service model.
What do you mean by the content pack?
A content pack is defined as a ready-made collection of visualizations and Power BI reports using your chosen service.
Mention some applications of Power BI
Business Analysis Data Analysis Database Administration IT Professional Data Science
Which professionals use Power BI the most?
Business Analysts Business Owners Business Developers
What are Filters in Power BI?
Conditions applied to data to select only a specific subset of data to be displayed.
Name some commonly used tasks in the Query Editor.
Connect to data Shape and combine data Group rows Pivot columns Create custom columns Query formulas
How can you depict a story in Power BI?
Every individual chart or visualization report generated is collected and represented on a single screen.
Describe the components of Microsoft's self-service BI solution.
Excel BI Toolkit and Power BI
What is XVelocity Engine?
In-memory analytics engine that can handle huge amounts of data, storing data in columnar databases.
Explain Power BI Designer.
It is a combined solution offered to upload the reports and dashboards to the PowerBI.com website for reference. It consists of Power Pivot, Power Query, and Power Table.
Why should we use Power BI?
It is an easy to for anyone, including non-technical people to connect, change and visualize raw business data
What are the critical components of the Power BI toolkit?
Power Query Power Pivot Power View Power Map Power Q&A
What are the three fundamental concepts of DAX?
Syntax: How the formula is written. Functions: use arguments in a particular order to perform a calculation. Context: Row context is applying a filter to a identify a single row. Filter context is applying one or more filters in a calculation to determine a result.
What are KPIs in Power BI?
The organizations set up KPIs for all the employees. These KPIs act as their targets. These KPIs are compared to previous performance and analyze the progress.
How do you reshape data in Power BI?
Using Data editor to manipulate and transform rows and columns.
What is GetData in Power BI?
an icon used to import data from the source
What is the caluclate function in DAX?
evalutes the sume of the Sales table sales amount column in a modified filter context.
What are some limitations of PowerBI
- No files larger than 1 GB - doesn't mix imported data accessed from real-time connections. - Very few data sources that allow real-time connections to power bi reports.
List the most common techniques for data shaping.
1) Adding indexes 2) Applying a sort order 3) Removing columns and rows
What are the various versions of Power BI?
1) Power BI Desktop 2) Power BI service 3) Mobile Power BI apps for iOS and Android devices
Difference between Power BI and Tableau
1) Tableau is capable of handling large volumes of data while PowerBi can only handle a limited amount of data. 2) Tableau is better suited to support the cloud with ease while PowerBi struggles in this aspect due to its capacity of handling large volumes of data 3) Tableau uses MDX for measures and dimensions and PowerBi uses Dax for calculating measures.
What is a slicer?
A sort of filter that can display a visual representation of all values that can be selected by users.
. What are the categories of data types?
All File Database Power BI Azure Online Services Other
. Define bi-directional cross filtering.
Allows data modelers to decide how they want their Power BI Desktop filters to flow for data, using the relationships between tables
What are the different stages in the working of Power BI?
Data Integration Data Processing Data Presentation
Can you have more than one functional relationship between two tables in a Power Pivot data model?
No there can be multiple inactive relationships but only one active relationship.
What is query folding in Power BI?
Query folding is used when steps defined in the Query Editor are translated into SQL and executed by the source database instead of your device.
How is the Schedule Refresh feature designed to work?
Users can set up for an automatic refresh over data based on daily or weekly requirements.
Can you have a table in the model which does not have any relationship with other tables?
Yes. 1) It can be used to present the user with parameter values to be exposed and selected in slicers. 2) used as a placeholder for metrics
. What is Power BI?
business intelligence tool used to consume data and create analytics reports.
What are Custom Visuals in Power BI?
like any other visualization, however it develops the custom visuals using a custom SDK.
When is a content pack used?
when you want to get up and running quickly instead of creating a report from scratch.
What are the various types of refresh options provided in Power BI?
4 types: 1) Package refresh - Synchronizes the PowerBI service and OneDrive, or SharePoint Online. 2) Model or data Refresh - refreshes the dataset within the PowerBi service with data from the original data source. 3) Tile Refresh - This updates the cache for tile visuals every 15 minutes on the dashboard once data changes. 4) Visual Container Refresh - refreshes the visible container and updates the cached report visuals within a report once the data changes.
What is the advanced editor?
Advanced editor is used to view queries that Power BI is running against the data sources importing data.
What is DAX?
Data Analysis Expressions: A collection of functions, operators and constants used in formulas to calculate and return values. Helps you create new information from data you already have.
What are some familiar sources for data in the Get Data menu in Power BI?
Excel, Power BI datasets, web, text, SQL server, and analysis services.
Name the data sources can Power BI can connect to?
Files, Content packs, Connectors.
What is "M language."
M is a programming language used in Power Query as a functional, case-sensitive language similar to other programming languages and easy to use.
What are the types of filters?
Manual auto Include/Exclude Drill-down Cross drill Filters Drillthrough filters URL Filters - transient Pass-through filters
How are relationships defined in PowerBI Desktop?
Manually - using foreign keys and primary keys. Automatically - PowerBI detects relationships between tables and creates them.
Where is data stored in Power BI?
Most of the time it is assisted by the cloud to store data, Microsoft Azure. It can also use a desktop service Azure SQL Database Azure Blob Storage
Mention important components of SSAS
OLP Engine - Used to extensively run the AdHoc queries Data Drilling - process of exploring details of the data with multiple levels of granualarity. Slicers - Process of storing the data in rows and cloumns. Pivot Tables - Helps in switching between the different categories of data stored between rows and columns.
What gateways does Power BI have and why should you use them?
Personal Gateway: Used by one person so that data can be imported. On-Premises: Supports direct query and usable by multiple users to refresh data.
What do you mean by grouping?
Power BI Desktop helps you to group the data in your visuals into chunks. You can, however, define your groups and bins.
What information is needed to create a map in Power Map?
Power Map can display geographical visualizations. Therefore, some location data is needed—for example, city, state, country, or latitude and longitude.
Which in-memory analytics engine does Power Pivot use?
Power Pivot uses the xVelocity engine. xVelocity can handle huge amounts of data, storing data in columnar databases.
Difference between Power Query and Power Pivot
Power Query is analyzing data and Power Pivot is about obtaining and transforming data. Power query is an ETL service tool while Power Pivot is an in-memory data modeling component
What are some differences in data modeling between Power BI Desktop and Power Pivot for Excel?
Power pivot supports only single directional relationships (One to many) and one import mode. Power BI Desktop supports bi-directional cross-filtering connections and multiple import options.
What are the different views available in Power BI Desktop?
Report View - add visualizations and publish it on the portal. Data view - data shaping performed using Query editor tools. Model View - Manage relationships between complex datasets.
What is row-level security?
Row-level security limits the data a user can view and has access to, and it relies on filters.
What are the major differences between visual-level, page-level, and report-level filters in Power BI?
Visual Level - single visualization Page Level - filters the entire page Report Level: Filters the entire report
Explain the building blocks of Microsoft Power BI.
Visualizations: Generating Reports from raw data. Datasets: Collection of data used to create the visualization. Reports: Group of visualizations. Dashboards: Single visualization Tiles: One of your charts in your final report or an individual visualization on final dashboard.
Why and how would you use a custom visual file?
You will use a custom visual file if the prepackaged files don't fit the needs of your business.
Explain responsive slicers in Power BI.
a developer can resize a responsive slicer to various sizes and shapes, and the data collected in the container will be rearranged to find a match.
What is Power Query?
a tool designed to import data from various data sources and enables you to clean, transform and reshape your data per your requirements.
What is Power Pivot?
add-on provided by Microsoft for excel in order to extend its analytical capabilities.
What is Power BI Desktop
an open-source application designed and developed to allow users to connect, transform and visualize data.
What is self-service BI, anyway?
refers to the ability of any person, technical or non-technical, to be able to generate reports and draw predictions by connecting to, transforming and analyzing their raw business data
. Why should you apply general formatting to Power BI data?
to make it easier for Power BI to categorize and identify data, making it considerably easier to work with.