100+ Power BI Developer Interview Questions and Answers

There are four types of joins in Power BI and SQL: inner join, left join, right join, and full outer join.

• Inner join returns only the matching records from both tables.

• Left join returns all records from the left table and the matching records from the right table.

• Right join returns all records from the right table and the matching records from the left table.

• Full outer join returns all records when there is a match in either the left or right table.

Sum calculates the sum of a column, while Sumx calculates the sum of an expression. Summarize creates a new table with summarized data, while Summarized column adds a calculated column to an existing table.

• Sum is used to calculate the sum of a column in a table.

• Sumx is used to calculate the sum of an expression over a table or a group of rows.

• Summarize creates a new table by grouping and summarizing data from an existing table.

• Summarized column adds a calculated column to an ...read more

Page level filters only filter data on a given page, while report level filters affect all data in the report.

• Report level filters are universal filters

• Page level filters only affect data on a specific page

• Report level filters affect all data in the report

• Page level filters only filter data on a given page

Calculated columns are computed during data loading, while measures are computed on the fly during data visualization.

• Calculated columns are created in the data model and stored in the underlying table.

• Measures are created using DAX expressions and are calculated dynamically based on the context of the visualization.

• Calculated columns consume memory and can impact performance, while measures are more efficient.

• Calculated columns are useful for static calculations, while measu...read more

Row level security in Power BI allows you to restrict data access based on user roles or filters.

• Row level security can be implemented by defining roles and filters in Power BI Desktop.

• Roles can be created and assigned to users or groups.

• Filters can be applied to tables or columns to limit data visibility.

• Row level security can be based on user attributes, such as department or region.

• Dynamic row level security can be achieved by using DAX expressions.

• Testing and validating r...read more

There are two types of subscriptions in Power BI Report Server.

• The two types of subscriptions are Power BI Report Server Standard and Power BI Report Server Enterprise.

• The Standard subscription allows for a single server deployment, while the Enterprise subscription allows for a distributed deployment.

• The Enterprise subscription also includes additional features such as high availability and disaster recovery.

• Both subscriptions require a license for each user accessing the re...read more

The number of refreshes allowed in a Power BI Premium account depends on the capacity size.

• The number of refreshes allowed varies based on the capacity size of the Power BI Premium account.

• For P1 capacity, up to 48 refreshes per day are allowed.

• For P2 capacity, up to 96 refreshes per day are allowed.

• For P3 capacity, up to 384 refreshes per day are allowed.

• Additional refreshes can be purchased if needed.

To enhance the performance of the dashboard, optimize data model, minimize visuals, and use calculated columns sparingly.

• Optimize the data model by reducing unnecessary columns and tables

• Minimize the number of visuals on the dashboard to reduce rendering time

• Use calculated columns sparingly as they can impact performance

• Avoid using unnecessary filters and slicers

• Consider using DirectQuery or Live Connection instead of importing all data

• Use query folding to push data transform...read more

Bookmarks in Power BI are a feature that allows users to save and organize specific views of a report or dashboard.

• Bookmarks help users to easily navigate and switch between different report views.

• They can be used to save filters, slicer selections, visualizations, and other report settings.

• Bookmarks can be created manually or through Power BI's recording feature.

• They can be accessed and managed through the Bookmarks pane in Power BI Desktop or the Bookmarks menu in Power BI ...read more

SUM calculates the sum of a column or expression, while SUMX calculates the sum of an expression over a table.

• SUM is used to calculate the sum of a column or expression in Power BI.

• SUMX is used to calculate the sum of an expression over a table in Power BI.

• SUM is typically used with a column reference, while SUMX is used with an expression.

• SUMX can be used to perform calculations on filtered or modified data.

• Example: SUM([Sales]) calculates the sum of the Sales column, while ...read more

Row Level Security is a feature in Power BI that allows you to restrict data access at the row level based on user roles and filters.

• Row Level Security (RLS) is used to control data access in Power BI based on user roles and filters.

• It allows you to define rules that determine which rows of data a user can see.

• RLS can be applied to tables or views in the data model.

• It is commonly used to restrict access to sensitive or confidential data.

• For example, you can use RLS to ensure ...read more

Common techniques for data shaping include removing columns/rows, grouping rows, pivoting columns, and creating custom columns.

• Removing unnecessary columns and rows can simplify the data and make it easier to analyze.

• Grouping rows can help aggregate data and provide a higher-level view of the information.

• Pivoting columns can transform the data to make it more readable and easier to analyze.

• Creating custom columns can add additional information to the data and help with analys...read more

Scheduled refresh allows for automatic updates of data in Power BI datasets.

• Scheduled refresh can be set up in the dataset settings under the 'Scheduled refresh' section.

• Some data sources may require a gateway to be set up for scheduled refresh to work.

• Scheduled refresh can be set to occur at specific intervals, such as daily or weekly.

• Scheduled refresh can also be set to occur at specific times, such as during off-peak hours.

• Scheduled refresh can be monitored and managed thr...read more

Various types of reports can be developed in Power BI.

• Power BI allows the development of interactive dashboards.

• Tabular reports can be created to display data in a structured format.

• Matrix reports are useful for summarizing data in a grid-like format.

• Charts and graphs can be used to visualize data trends and patterns.

• KPI reports can be developed to track key performance indicators.

• Paginated reports are suitable for printing or generating PDFs.

• Drill-through reports allow users...read more

Gauge charts are used to visually represent a single value within a given range.

• Gauge charts are commonly used in business dashboards to display key performance indicators (KPIs).

• They provide a quick and intuitive way to assess the current status or progress towards a goal.

• Gauge charts can be used to show metrics such as sales targets, customer satisfaction scores, or production efficiency.

• They are effective in highlighting deviations from the desired value or target.

• Gauge ch...read more

Role based security can be created in SSAS by defining roles and assigning permissions to them.

• Create roles in SSAS and define permissions for each role

• Assign users or groups to each role

• Use Windows authentication or custom authentication to manage access to roles

• Test the security model thoroughly to ensure it is working as expected

Power BI has various types of filters such as visual, page, report, drill-through, and slicer filters.

• Visual filters apply to a single visual or chart.

• Page filters apply to all visuals on a single page.

• Report filters apply to all visuals in a report.

• Drill-through filters allow users to navigate to more detailed data.

• Slicer filters allow users to filter data across multiple visuals.

DAX is a formula language used in Power BI. It has different types of functions including table DAX functions.

• DAX stands for Data Analysis Expressions

• DAX functions can be categorized into different types such as aggregation, time intelligence, filter, etc.

• Table DAX functions are used to manipulate tables in Power BI

• Examples of table DAX functions include FILTER, SUMMARIZE, ADDCOLUMNS, etc.

Power BI provides various types of security to protect data and control access.

• Row-level security allows restricting data access based on user roles or filters.

• Data encryption ensures that data is securely stored and transmitted.

• Azure Active Directory integration enables centralized user authentication and access control.

• Power BI service provides access and sharing controls to manage permissions.

• Data loss prevention policies help prevent accidental sharing of sensitive inform...read more

Power BI is a powerful business intelligence tool that allows users to visualize and analyze data from various sources.

• Power BI is a business intelligence tool developed by Microsoft.

• It allows users to connect to multiple data sources and create interactive visualizations and reports.

• Power BI provides a wide range of data transformation and modeling capabilities.

• It supports various data visualization techniques such as charts, graphs, and maps.

• Power BI also offers advanced an...read more

Yes

• Dealing with complex data transformations

• Handling large datasets and optimizing performance

• Creating dynamic and interactive visualizations

• Integrating Power BI with other data sources

• Implementing security and access controls

Power BI has three connection modes: Import, DirectQuery, and Live Connection.

• Import mode imports data into Power BI and creates a dataset.

• DirectQuery mode connects to the data source and queries data in real-time.

• Live Connection mode connects to a published dataset in Power BI Service.

• Import mode is best for small to medium-sized datasets, while DirectQuery and Live Connection are better for large datasets.

• DirectQuery and Live Connection require a live connection to the data...read more

Power BI reports can be embedded into SharePoint using the Power BI web part.

• Add the Power BI web part to the SharePoint page

• Enter the URL of the Power BI report in the web part properties

• Configure the web part settings to customize the report display

• Ensure that the SharePoint site and Power BI report are in the same organization

• Use the Power BI service to manage report permissions

Calculate column is a static column while measure is a dynamic calculation.

• Calculate column is computed during data load and cannot be changed afterwards.

• Measure is computed on the fly based on user interaction with the report.

• Calculate column is used for static calculations like concatenation or simple arithmetic.

• Measure is used for dynamic calculations like aggregation or percentage.

• Calculate column can consume more memory and slow down performance.

• Measure is more efficient...read more

Sql server agent is used for scheduling and automating tasks in SQL Server.

• Automates routine tasks like backups, index maintenance, etc.

• Allows scheduling of jobs to run at specific times or intervals.

• Provides alerts and notifications for job failures.

• Can be used to execute PowerShell scripts or SSIS packages.

• Helps improve database performance and reliability.

Slicers and filters are both used to control data visibility in Power BI, but slicers are visual elements while filters can be applied programmatically.

• Slicers are visual controls that allow users to select values from a predefined list, which filters the data accordingly.

• Filters can be applied programmatically using DAX formulas or Power Query M language.

• Slicers are typically used for interactive data exploration and analysis, while filters are more commonly used for data ma...read more

Performance of reports can be improved by optimizing queries, reducing data volume, using efficient visuals, and caching data.

• Optimize queries by removing unnecessary columns and filters

• Reduce data volume by aggregating data at the source or using incremental refresh

• Use efficient visuals like matrix instead of tables for large datasets

• Cache data to reduce query times for frequently accessed data

Automate data handling using Power BI features like data refresh and data modeling.

• Utilize Power BI data refresh feature to automatically update employee data from a data source.

• Implement data modeling in Power BI to organize and analyze the 500 employee data efficiently.

• Leverage Power BI automation tools like Power Query and DAX to streamline data processing tasks.

• Create interactive reports and dashboards in Power BI to visualize and analyze the employee data effectively.

Data modeling is the process of creating a visual representation of data to analyze and make informed decisions. DAX is a formula language in Power BI used for calculations.

• Data modeling involves organizing and structuring data to create relationships between different data sets.

• DAX (Data Analysis Expressions) is a formula language used in Power BI to perform calculations and create custom measures.

• Calculating revenue using DAX involves summing up the product of price and qua...read more

I have worked on various types of data sets including sales data, customer data, financial data, and social media data.

• Sales data

• Customer data

• Financial data

• Social media data

Schedule report export and email to client using Power BI

• Create a Power BI report with the data to be exported

• Set up a data refresh schedule for the report

• Use Power BI subscription feature to email the report to the client

Power BI Pro is a user-based license that allows individuals to publish and share reports, while Power BI Premium is a capacity-based license that provides dedicated resources for larger organizations.

• Power BI Pro is a user-based license, while Power BI Premium is a capacity-based license.

• Power BI Pro allows individuals to publish and share reports, while Power BI Premium provides dedicated resources for larger organizations.

• Power BI Pro is suitable for small to medium-sized ...read more

Tableau and Power BI are both data visualization tools, but Power BI is more user-friendly and affordable while Tableau is more powerful and flexible.

• Power BI is easier to use and has a lower learning curve

• Tableau has more advanced features and customization options

• Power BI is more affordable for small to medium-sized businesses

• Tableau is better for large enterprises with complex data needs

• Power BI integrates well with other Microsoft products

• Tableau has a larger community an...read more

Measures are dynamic calculations based on the data model, while calculated columns are static calculations added to a table.

• Measures are used in visualizations and change based on filters and slicers

• Calculated columns are added to a table and are not affected by filters or slicers

• Creating a custom table involves defining the columns and their data types, and then populating it with data

• Custom tables can be created using Power Query or DAX formulas

Import model is a Power BI feature that allows you to import data from various sources and create a data model.

• Import model is used to create a data model in Power BI.

• It allows you to import data from various sources such as Excel, CSV, SQL Server, etc.

• You can create relationships between tables, add calculated columns, and measures.

• Import model is useful when you have large amounts of data that need to be transformed and modeled.

• It is also useful when you need to combine dat...read more

Filters are used to restrict data at the report level, while slicers are interactive visual filters applied to specific visuals.

• Filters are applied at the report level and affect all visuals, while slicers are applied to specific visuals only.

• Slicers allow users to interactively filter data by selecting values from a list or range.

• Filters can be applied to multiple visuals at once, while slicers are applied individually to each visual.

• Slicers provide a more user-friendly way ...read more

A line graph is typically used to represent historical sales data.

• Line graph is ideal for showing trends over time

• It helps in visualizing the sales performance over different time periods

• Can be used to compare sales data from different years or quarters

There are three types of gateways in Power BI: On-premises data gateway, Personal gateway, and Power BI Gateway (Enterprise). Each serves a different purpose.

• On-premises data gateway is used to connect on-premises data sources to Power BI service.

• Personal gateway is used for individuals to refresh data from on-premises data sources.

• Power BI Gateway (Enterprise) is used for organizations to manage data refresh for cloud and on-premises data sources.

• Gateways are used to securel...read more

Star schema has a single fact table connected to multiple dimension tables, while snowflake schema has normalized dimension tables.

• Star schema denormalizes dimension tables, making it easier to query but potentially less efficient for storage.

• Snowflake schema normalizes dimension tables, reducing redundancy but potentially making queries more complex.

• Star schema is commonly used for data warehouses with denormalized data, while snowflake schema is used for normalized OLAP sys...read more

CALCULATED function is used in Power BI to create custom calculations based on existing data in a report.

• CALCULATED function is used to create custom calculations in DAX (Data Analysis Expressions) language.

• It allows users to define complex calculations based on existing data in the report.

• CALCULATED function can be used with other DAX functions to perform calculations like aggregations, comparisons, and conditional logic.

• Example: CALCULATED column can be used to calculate pr...read more

Star schema is a data warehouse schema where a central fact table is connected to multiple dimension tables. Snowflake schema is a normalized form of star schema.

• Star schema consists of a central fact table connected to multiple dimension tables

• Snowflake schema is a normalized form of star schema where dimension tables are further normalized into sub-dimension tables

• Star schema is denormalized for faster query performance, while snowflake schema is normalized for easier maint...read more

I'm sorry, but I cannot answer that question as it is too specific and lacks context.

• Without more information about the context of the question, it is impossible to provide a meaningful answer.

• It is important to clarify the purpose of the question and the specific industry or region being referred to.

• If you have more information or a specific scenario in mind, I would be happy to provide guidance on how to approach the problem.

Reports are detailed and provide specific information, while dashboards are high-level and provide an overview.

• Reports are typically longer and more detailed than dashboards

• Reports are often used to provide specific information to a targeted audience

• Dashboards are high-level and provide an overview of key metrics

• Dashboards are often used to monitor performance and identify trends

• Reports are usually static, while dashboards are interactive and allow for real-time data explorat...read more

Implement security to data using row-level security (RLS)

• Use user roles and permissions to restrict access to specific data

• Leverage Power BI's built-in security features such as dataset security and data categorization

• Implement dynamic security based on user context or attributes

• Utilize Power BI's security features like Azure Active Directory integration for authentication and authorization

Use a disconnected table to add a slicer with top customers without using filters.

• Create a disconnected table with a list of top customers.

• Add this disconnected table to the report.

• Use the disconnected table as a slicer to filter data based on top customers.

Parameters are used for dynamic values that can be changed, while constants are used for fixed values in M query.

• Use parameters for values that may change frequently, such as dates or file paths

• Use constants for values that are fixed, such as column names or static calculations

Use Power BI bookmarks and buttons to dynamically change chart visuals based on user selection.

• Create multiple chart visuals for different data sets

• Use bookmarks to save different chart configurations

• Link selection buttons to bookmarks to dynamically switch between charts