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Babinsky's avatar
Babinsky
Helper I
9 years ago
Solved

Create Relationship

Hi everyone, I have a question - I'm getting the following error message.

 

You can't create a relationship between these two columns because one of the columns must have unique values.  

 

These two columns are date fields.  One is week format is other dat format, so I understand the confilct.  

 

Does anyone have any suggestions?  Thanks!

 

Babinsky

 

 

 

  • In the tabular database model, you can only create a relationship between two tables when at least one of the columns being used to create the relationship has unique values. It seems like both of your date fields have duplicates values.

     

    You need to deteremine which of these two date columns in your two tables should have a unique values. Then use the Power BI Desktop query tool to de-duplify these duplicate date values so that the query outputs a table with unique column values. After that, you should be able to create the relationship.

5 Replies

  • TedPattison's avatar
    TedPattison
    Microsoft Employee

    In the tabular database model, you can only create a relationship between two tables when at least one of the columns being used to create the relationship has unique values. It seems like both of your date fields have duplicates values.

     

    You need to deteremine which of these two date columns in your two tables should have a unique values. Then use the Power BI Desktop query tool to de-duplify these duplicate date values so that the query outputs a table with unique column values. After that, you should be able to create the relationship.

    • Babinsky's avatar
      Babinsky
      Helper I

      Thanks for the suggestion Ted.  Question - how do you de-duplify these duplicate date values?

      • TedPattison's avatar
        TedPattison
        Microsoft Employee

        First, make sure that the column in question is based on Date and not DateTime when you examine it in the query edito window. Next, you use the Group By step so that every row withthe same date is collapsed into the single row.

         

        Is this table you are working with a specialized Calendar table?