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Power BI - Questions & Answers | Business Analytics & Intelligence | Processes & Tools | Part 7

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Question: What techniques can be used to reduce the file size of a Power BI report? Suggested Answer: Reducing the file size of a Power BI report (.pbix) improves performance, reduces load times, and makes sharing easier.  Key techniques to reduce file size 1. Optimize Data Sources Import Mode vs. DirectQuery/Dual Mode: Use DirectQuery or Live Connection for large datasets instead of importing. If importing, filter unnecessary data at the source. Use Query Folding : Ensure Power Query transformations are pushed to the source (SQL, etc.). Limit Rows : Load only necessary historical data (e.g., last 3 years instead of 10). 2. Clean & Transform Data Efficiently Remove Unused Columns : Delete unnecessary columns in Power Query. Use Appropriate Data Types : Smaller types (e.g., integer instead of text for IDs) reduce size. Replace High-Cardinality Text with IDs : Use numeric keys instead of long text labels. Avoid Complex Columns : JSON / XML columns bloat size—parse them in Po...

Power BI - Questions & Answers | Business Analytics & Intelligence | Processes & Tools | Part 6

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What is the difference between a heat map and a filled map in Power BI? Suggested Answer: Difference Between a Heat Map and a Filled Map in Power BI Both visualizations represent geographic data but serve distinct purposes. 1. Heat Map Purpose: Visualizes density/intensity of data points using color gradients. How It Works : Represents individual data points (e.g., cities, stores) as colored circles. Color intensity (e.g., light to dark) or size indicates magnitude (e.g., sales, population). No geographic boundaries—just points on a map. Use Cases : Show clusters of high/low activity (e.g., sales hotspots, crime incidents). Compare relative values across locations. Example : A map with red (high sales) to blue (low sales) circles for each store. Power BI Setup : Use the "Map" visual (not "Filled Map"). Drag: Location (e.g., city, latitude/longitude) to the "Location" field. Metric (e.g., sales) to the "Size" or "Color saturation" field....

Power BI - Questions & Answers | Business Analytics & Intelligence | Processes & Tools | Part 5

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  Question: State all the commonly used DAX Functions in Power BI. Suggested Answer: Data Analysis Expressions (DAX) is the native formula and query language for Microsoft PowerPivot , Power BI Desktop and SQL Server Analysis Services (SSAS) Tabular models. DAX includes some of the functions that are used in Excel formulas with additional functions that are designed to work with relational data and perform dynamic aggregation. DAX data types Integer Real Currency Date (datetime) TRUE/FALSE (Boolean) String Variant Note: The BLOB (binary large object) data type is managed by the Tabular model but cannot be directly manipulated by DAX expressions. Most Common  DAX Function Types with examples 1. Aggregation Functions Calculate sums, averages, counts, etc. SUM() : Total Sales = SUM (Sales[Amount])  // Sum of sales amounts AVERAGE() : Avg Price = AVERAGE (Products[Price])  // Average product price COUNTROWS() : Order Count = COUNTROWS (Orders)  // Number of orde...

Power BI - Questions & Answers | Business Analytics & Intelligence | Processes & Tools | Part 4

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Question: How do you create a gauge chart in Power BI? Suggested Answer: A gauge chart (also called a speedometer or radial gauge) visualizes a single metric’s progress toward a goal.  Here’s a step-by-step guide: Step 1: Enable the Gauge Visual Open your Power BI report in Power BI Desktop. In the Visualizations pane, click the Gauge icon (resembles a speedometer). If you don’t see it, click ... (More options) → Get more visuals → Search for "Gauge" and import it. Step 2: Add Data to the Gauge Value : Drag your KPI (e.g., Sales Amount ) to the "Value" field. Target (Optional) : Add a goal (e.g., Sales Target ) to the "Target" field. Minimum/Maximum (Optional) : Manually set the gauge’s scale range by typing values in the " Minimum " and " Maximum " fields under Format → Gauge axis . Or, drag columns to " Minimum Value " and " Maximum Value " (e.g., 0 to 100%).

Power BI - Questions & Answers | Business Analytics & Intelligence | Processes & Tools | Part 3

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  What is the role of the M language in Power BI? Suggested Answer: The M language (also called Power Query Formula Language) is a critical component of Power BI, primarily used for data extraction, transformation, and loading (ETL). Here’s a detailed breakdown of its role: 1. Primary Role: Data Transformation M is the backbone of Power Query Editor, where it: Cleanses (e.g., removes duplicates, fixes errors). Reshapes (e.g., pivots/unpivots, splits columns). Enriches (e.g., merges tables, adds custom columns). Filters (e.g., removes irrelevant rows/columns). Example: m = Table.SelectRows(Source, each [Sales] > 1000) // Filters rows where sales exceed 1000 2. Key Features of M a) Declarative & Functional M scripts describe what to do (not step-by-step how), making it intuitive. Uses functions (e.g., Table.ReplaceValues, Text.Trim) and nested expressions. b) Query Folding Pushes transformations back to the source system (e.g., SQL Server) to improve performance. Example: A WH...

Power BI - Questions & Answers | Business Analytics & Intelligence | Processes & Tools | Part 2

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Question: Describe the different layers involved in Power BI architecture. Suggested Answer: The Power BI architecture consists of multiple layers that work together to transform raw data into actionable insights. A breakdown of the key layers is given below: 1. Data Sources Layer Purpose: Contains raw data from various sources. Examples: Databases (SQL Server, Oracle, MySQL) Files (Excel, CSV, JSON) Web APIs & SaaS apps (Salesforce, Google Analytics) Big Data (Azure Synapse, Hadoop) Streaming data (IoT, Kafka) 2. Data Transformation Layer (Power Query) Purpose: Cleans, transforms, and prepares data for analysis. Key Tasks: Data extraction (connectors) Filtering, merging, pivoting Handling missing values Query folding (pushing transformations back to the source) Tools: Power Query Editor in Power BI Desktop 3. Data Modeling Layer Purpose: Structures data for efficient analysis. Key Components: Star Schema : Fact tables (metrics) linked to dimension tables (categories) Relations...

Power BI - Questions & Answers | Business Analytics & Intelligence | Processes & Tools | Part 1

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Power BI - Simplified for You! Imagine you have a giant pile of numbers, sales reports, customer surveys, or even social media stats—and you need to make sense of it all. That’s where Power BI comes in! Power BI is a free (with paid upgrades) tool from Microsoft that turns boring data into interactive, visual stories. Think of it like a supercharged mix of Excel + PowerPoint + magic dashboards. Definition:  Power BI is a business analytics service developed by Microsoft that enables organizations to visualize, analyze, and share data across departments or with external stakeholders. It provides an integrated suite of tools for data ingestion, transformation, modeling, and interactive reporting, supporting self-service analytics and enterprise-grade business intelligence (BI).