chapter one

1 Interactive DAX and semantic model concepts

 

This chapter covers

  • Understanding interactivity and evaluation context in Power BI
  • Modeling relationships, table expansion, and data lineage
  • Exploring user-driven filters and real-time report interactivity
  • Navigating expanded tables and disconnected entities
  • Laying the foundation for model-aware, filter-driven DAX logic

When writing DAX measures, it’s tempting to think you see and control all the logic. In reality, much of the DAX running in your report is generated automatically behind the scenes in response to slicer selections, report-level filters, and visuals on the canvas.

This chapter reveals that hidden layer of logic and shows how:

  • The semantic model powers interactivity
  • Filters flow silently across relationships and tables
  • DAX interprets user actions and reshapes queries on the fly

Grasping these concepts is essential for writing DAX that behaves predictably, intentionally, and efficiently. By the end, we’ll shift from thinking in terms of static formulas to designing model-aware filter logic that responds naturally with how users interact with your reports.

1.1 Interactive DAX mode

A central theme of this book is Interactive DAX—the idea that formulas are inherently dynamic and responsive to user-driven changes in the report.

DAX runs in two distinct modes:

1.2 Context in DAX

1.3 How users influence DAX

1.4 How interaction works

1.4.1 Scenario – a simple measure meets a live report

1.4.2 Behind the scenes

1.4.3 Asking the right questions

1.4.4 The art of interactive DAX

1.5 Power BI semantic model — relationships, expansion, and lineage

1.5.1 What is a semantic model?

1.5.2 From tables to unified models

1.5.3 Relationships in Power BI

1.5.4 Expanded tables — how DAX sees the model

1.5.5 Data lineage — tracking a column’s origins

1.5.6 What can break lineage?

1.6 Semantic models as a unified interactive system

1.6.1 Complex semantic models—beyond the basics

1.6.2 Disconnected entities in a unified semantic model

1.6.3 Why disconnected tables work

1.7 Connected vs. disconnected recordsets in interactive mode

1.7.1 When lineage is lost