Season 1

Namaste Power BI

Episode 6

Advanced Power Query

⏱ 50:00

Episode Summary

Beyond basics — Merge (JOIN), Append (UNION), Unpivot, Pivot, Conditional Columns, and custom M functions. The transformation patterns that separate beginners from professionals.

This is Episode 6 of the free Namaste Power BI course on DevWithData — covering advanced power query. Watch the video above, then pass the MCQ checkpoint to unlock the next episode and update your Data Readiness Index score.

Key Takeaways

→Merge Queries = SQL JOIN (horizontal combination)
→Append Queries = SQL UNION ALL (vertical stacking)
→Unpivot transforms wide data into tall normalized format
→Custom M functions enable reusable transformation logic

⚠ Common Interview Pitfalls

•Using Merge when Append is needed (or vice versa)
•Unpivoting before removing unnecessary columns
•Writing complex M by hand when the GUI can generate it

Official Reference

Deepen your understanding with official Microsoft documentation.

PL-300 Official Training Course

Microsoft's official instructor-led training for the Power BI Data Analyst certification.

https://learn.microsoft.com/en-us/training/courses/pl-300t00

Power BI Documentation

Complete reference for Power BI Desktop, Power BI Service, and Power BI Embedded.

https://learn.microsoft.com/en-us/power-bi/

Content on DevWithData is original and inspired by official Microsoft resources. The links above point directly to Microsoft Learn — always the authoritative source.

← Ep 5: Power Query Basics

Ep 7: Modeling Principles →

Episode Checkpoint

Sign in to attempt the quiz and unlock the next episode.