Microsoft Fabric Apps Tutorial | Build Actual vs Budget Writeback for Power BI

Power BI is read-only — so budgets and targets always end up in spreadsheets emailed around and re-imported by hand. In this video I fix that: a Microsoft Fabric Data App that writes straight to a database, and a composite Power BI model that shows Actual vs Budget LIVE — no refresh, no gateway, no spreadsheets.

You'll see the full build: scaffold a Fabric Data App with Rayfin, capture budgets to a Fabric SQL database, land actuals in a Lakehouse, wire up a composite model with DirectQuery, and publish it — all cloud-native.

⏱️ CHAPTERS 00:00 The payoff (writeback in action) 02:56 The architecture 07:08 About me 07:44 Part 1: Actuals into a Lakehouse 08:44 Part 2: The Fabric writeback app (Rayfin) 13:18 Create Fabric App using Claude + VS Code 16:20 Scaffolding 17:00 Run npm 17:45 Update files for Fabric App 21:36 Create UI 24:40 Error Handling 28:00 Rayfin up (deploy) 28:40 First glimpse of Fabric App 29:18 HTTP Error 404 31:26 Second glimpse of Fabric App 31:50 SQL database check 33:00 Part 3: The composite model (DirectQuery + measures) 41:10 Part 4: Publish + cloud connections (no gateway) 42:28 The payoff — Actual vs Budget, live 46:54 Tips & gotchas that'll save you hours 50:54 What's next

🛠️ WHAT'S COVERED • Fabric Data Apps with the Rayfin framework (scaffold → entity → deploy) • Reading dropdown values LIVE from a semantic model with DAX • Writeback to a Fabric SQL database • Composite model: Import (actuals) + DirectQuery (budget) • Generating a clean date table & building Budget/Variance/Achievement measures • Cloud connections with OAuth — zero gateways