Power BI
Explain the building blocks of Microsoft Power BI?
Datasets: The data sources imported into Power BI.
Reports: Collections of visuals based on datasets.
Dashboards: Single-page summaries created from multiple reports.
Workspaces: Collaborative environments for managing content and sharing insights among users.
What do you mean by the content pack?
A content pack in Power BI is a pre-packaged collection of related dashboards, reports, datasets, and Excel files that can be shared with users. Content packs can be created by organizations or sourced from third-party providers to facilitate easy access to common analytics resources.
difference between a calculated column and a measure.
A calculated column is computed during data load and stored within the model as part of the table; it evaluates row-by-row. A measure calculates results dynamically based on filters applied during report interactions, providing aggregated results across rows
Power BI keys : workspace, power bi service, slicer , filter , gateways
difference between SUM and SUMX in DAX.
SUM() calculates total values directly from a specified column across all rows without any additional context. In contrast, SUMX() evaluates an expression over a table row-by-row before summing up results; it's useful when calculations involve multiple columns or require context-specific evaluations
Semantic Model?
A Semantic Model defines how data elements relate within databases or datasets while providing business logic through measures, hierarchies, metadata definitions etc., facilitating easier understanding and analysis by end-users without needing deep technical knowledge about underlying structures.
A semantic model is an abstraction layer that sits between raw data and business users or applications
Example : dataset is semantic model : sits between reports and database
How do you handle many-to-many relationships in Power BI?
Many-to-many relationships can be handled by creating bridge tables that connect two tables indirectly. This involves creating an intermediary table that contains unique values from both related tables, allowing for effective filtering and aggregation
difference between VALUES and DISTINCT in DAX?
Both VALUES and DISTINCT return unique values from a column; however, VALUES also returns blank values if they exist within the column while DISTINCT does not. VALUES is often used when needing context-aware results based on filter context
the purpose of the CROSSFILTER function in DAX?
The CROSSFILTER function changes how filters propagate between two related tables during calculations. It allows users to specify whether filtering should be unidirectional or bidirectional when evaluating measures involving relationships
Difference between the SUM and SUMX functions in DAX?
— Answer: The SUM function in DAX is an aggregation function that calculates the sum of a numeric expression for a specified column or table
Total Sales = SUM(‘Sales’[SalesAmount])
The SUMX function, on the other hand, is an iterator function that applies a calculation expression to each row of a table and then sums up the results.
Total Sales = SUMX(‘Sales’, ‘Sales’[Quantity] * ‘Sales’[Price])
Summarize Table = SUMMARIZE(Orders, Orders[CustomerID], Orders[ProductID], “TotalSales”, SUM(Orders[Sales]))
Add column Table = ADDCOLUMNS(Orders, “Profit”, Orders[Sales] — Orders[Cost])
Category Sales = CALCULATE(SUM(‘Orders’[Sales]), FILTER(‘Orders’, ‘Orders’[Category] = “Bike”))
