Power BI Semantic Model Creation in Fabric

Hi, amenbouallagui 

The Assume Referential Integrity option applies only to relationships between tables that are in DirectQuery mode and come from the same data source. If your table is in import mode or from a different source, this option should not be available, and its activation may cause an error. You can check the following links:

Solved: Referential integrity in composite model - Microsoft Fabric Community

Model relationships in Power BI Desktop - Power BI | Microsoft Learn

If the integrity of the model is compromised, it can cause errors when trying to modify relationships. Ensure that all tables and relationships are properly defined, and that there are no missing or renamed tables.
Sometimes, software bugs can cause unexpected behavior. Make sure you're using the latest version of Power BI and check for any known issues or updates that might address this issue.
As a workaround, you can try manually editing the model's metadata or using a different approach to define the relationship. For example, if a direct method is causing the problem, you can use a SQL endpoint to create a semantic model. You can refer to the following post:

Solved: Referential Integrity Issue in Model (probably con... - Microsoft Fabric Community

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Best Regards

Yongkang Hua

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