Power BIStudy Notes

Building a Sales Dashboard

A step-by-step walkthrough of designing, modeling, and publishing a real-world Power BI sales dashboard.

Calculated Columns vs Measures

Learn the fundamental DAX distinction between calculated columns, which compute row-by-row and are stored, and measures, which compute dynamically based on fil…

Choosing the Right Visual

How to match Power BI visual types to the shape of your data and the question you're actually answering, and the common chart-selection mistakes to avoid.

Connecting to Data Sources

How Power BI connects to files, databases, and web sources, including authentication methods and the tradeoffs between Import, DirectQuery, and Live Connection.

Custom Visuals

How to source, vet, and build custom Power BI visuals beyond the built-in gallery, from AppSource certification to the pbiviz SDK.

Dashboards vs Reports

The structural and behavioral differences between Power BI reports and dashboards — interactivity, refresh timing, alerts, and mobile layout.

Data Refresh

Understand how Power BI keeps report data current through scheduled, incremental, and real-time refresh strategies, and the role of the on-premises data gatewa…

DAX Aggregation Functions

Aggregation functions like SUM, AVERAGE, COUNT, and their X-suffixed iterator counterparts are the workhorses for summarizing data in DAX measures.

DAX Variables and Iterators

VAR and RETURN make complex DAX measures more readable and performant by caching intermediate results, especially when combined with iterator functions.

Drill-Down and Drill-Through

The difference between drilling within a visual's hierarchy and drilling through to a dedicated detail page, and how to configure both correctly.

Filter Context and CALCULATE

Filter context determines which rows a DAX measure sees, and CALCULATE is the only function that can directly reshape that context.

Introduction to DAX

DAX (Data Analysis Expressions) is the formula language powering calculations in Power BI, Excel Power Pivot, and Analysis Services.

Power BI Best Practices

A practical checklist of proven techniques for building fast, maintainable, and trustworthy Power BI reports.

Power BI Desktop Setup

How to install Power BI Desktop, navigate its Report, Data, and Model views, and configure key options before building your first report.

Power BI Interview Questions

Common Power BI interview questions across fundamentals, DAX, modeling, and scenario-based problem solving, with strong answers.

Power BI Quick Reference

A fast-lookup cheat sheet of core DAX functions, UI shortcuts, common error messages, and licensing tiers.

Power BI vs Tableau

A grounded comparison of Power BI and Tableau across modeling, calculation languages, licensing, and ecosystem fit.

Power Query Basics

Learn how Power Query lets you connect, shape, and clean data before it ever reaches your Power BI model, using a repeatable, no-code ETL workflow.

Publishing to Power BI Service

How a .pbix file moves from Power BI Desktop into the Service, what artifacts it creates, and what you must configure before scheduled refresh will actually wo…

Relationships and Star Schema

Understand how Power BI relationships work and why a star schema of fact and dimension tables is the recommended foundation for accurate, performant models.

Report Formatting and Themes

How to use theme JSON, conditional formatting, bookmarks, and custom number formats to keep a Power BI report visually consistent and on-brand.

Row-Level Security

How Power BI restricts which data rows a user can see through DAX-defined roles, the static-vs-dynamic distinction, and what RLS does not protect.

Scheduled Refresh and Gateways

How Power BI keeps Import-mode datasets current on a schedule, why on-premises sources need a gateway, and how to diagnose refresh failures.

Slicers and Filters

How Power BI's three filtering layers-slicers, visual filters, and page/report filters-combine, sync, and interact with DAX filter-context functions.