Cannot create relationship between two columns.

[Gowtham]

Hi everyone, I am new to power BI. I connected to an Excel data source and found the relationships between the tables are automatically created. But there was not relationship established bwetween "Oeder" and "OrderDetails" table based on "OrderId".

When i tried to establish the relation manually, it was shown an error message as follows "you cant create a relationship between these two columns because one of the coulmns  have unique values". I searched for this topic in the forum but still couldnt find a solution. I also checked the data and made sure that the "OrderId" column in "Orders" table contains only unique values. Kindly guide me solving this issue..

[ankitpatira]

@Gowtham Can you ensure order ids in table OrderDetails are all present in OrderId table ie there are no values in Orderdetails table that is not present in OrderId table.

[Gowtham]

@ankitpatira Thanks again for your reply. It was a data issue as there was a NULL value in the OrderId column. Now that has been corrected and I am ablue to create  a relationship..!!

[gautik92]

If i am taking Date as Field for relationship it doesnot have unique values and it has duplicate values so can i create a relationship with t

[Gowtham]

@ankitpatira Thanks for your immediate response. Yes i have checked and made sure that all the OrderId values in OrderDetails Table are in the Orders Table too. What else could possibly be the reason for this error?

[ankitpatira · Accepted solution]

@Gowtham OrderId has unique values and non null ?