What is referential integrity?

< 1 min read

Referential integrity ensures every foreign key in a fact table matches a valid primary key in a dimension table.
In my project, each Sales record had to map to an existing Customer ID in the Customer table.
When some IDs were missing, visuals showed blank category rows.
It also caused incorrect totals because unmatched records were grouped as “Unknown”.
Power BI relationship warnings appeared during data refresh.
We fixed it by cleaning source data and adding default “Unknown Customer” records.
This improved join accuracy and prevented data loss in reports.
Maintaining referential integrity keeps filters reliable across dimensions.
It ensures business users trust the numbers in dashboards.

Power BI Essentials