Can't create a table relationships

Hi, melste1 

Sometimes, null or blank values in the column you're trying to associate can cause unexpected behavior. Make sure that the column you're trying to create a relationship in doesn't contain null or null values. If so, consider filtering it out or replacing it with a placeholder value. More details on working with null or blank values. You can check the document:

Tips and tricks for creating reports in Power BI - Power BI | Microsoft Learn

Make sure that at least one column in the relationship has a unique value. Power BI requires that one end of the relationship has a unique value to establish a one-to-many or one-to-one relationship. If both columns contain duplicate values, consider creating a dimension table that contains the unique values of the relationship.

You can refer to the following link:

Solved: Can´t create a relationship between two columns be... - Microsoft Fabric Community

Solved: You can't create a relationship between these two ... - Microsoft Fabric Community

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Best Regards

Yongkang Hua

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