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Relationships and duplicate
Hi,
I have 3 tables from sql server and I tried to connect them via their keys in PowerBI Desktop. (T1->T2 and T1->T3). T1 and T2 is ok but when I try T1 and T3 I get this message "one of the tables must contains unique values" (Im afraid deleting these duplicate will affect my results). And when I tried to delete them, I have this error : this step generates a query that is not supported in the Direct Query mode" with the option "dump all tables on Import mode" thing that I dont want because the tables are really huge. Any ideas?
1 Reply
To create a one-to-many relationship, the one side must have unique values and no nulls in the column you are creating the relationship on. If this doesn't work for your situation, you may need a many-to-many relationship.
I can't tell if you do or not from the information you've given but if you do need many-to-many, I'd recommend reading this first:
https://www.sqlbi.com/articles/many-to-many-relationships-in-power-bi-and-excel-2016/
