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Margaret Q. Ombere
Margaret Q. Ombere

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Understanding the relationshipi power Bi and its importance

Power BI Relationships: What They Are & Why They Matter

In Power BI, relationships connect tables using a shared column (like ProductID) so your data model can work properly. Without them, your visuals may be wrong or incomplete.

📘 What’s a Relationship?

A relationship tells Power BI how two tables are linked. For example:

  • Sales.ProductID connects to Products.ProductID
  • This lets Power BI know which product each sale refers to

🔢 Types of Relationships

  • One-to-Many (1:*) – Most common (e.g., Products → Sales)
  • Many-to-Many (:) – Needs careful handling or a bridge table
  • One-to-One (1:1) – Rare but useful in master-detail scenarios

✅ Why It Matters

  • Accurate visuals: Relationships ensure correct totals and filtering
  • Better models: Cleaner structure with separate tables
  • Faster reports: Power BI performs better with proper relationships
  • DAX support: Functions like RELATED() depend on them

NB:

  • Makes sure one table has unique values
  • Avoid bi-directional filters unless needed
  • Use a star schema (fact table at center, dimension tables around)

📌 Strong relationships equals(=) strong reports. Takes a few minutes to review them before you build!


powerbi #lux #datamodeling

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