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Dear Community;
I'm quite familiar with Tabular Data Models and I heve been working with Power BI since few years already, I clearly understand the principle of the Relational Data Model, this time I'm trying to create a One to Many relation between 2 tables and I got a message in Power BI Desktop warning that is a cardinality Many-Many.
I've have checked by all the meaninings the uniqness of the values in my Column key and they're unique in one of the table, herein some screenshots to support my issue:
Data Model:
Message when I try to set Relationship:
Table Verification for Distinct Values on Table N-1 Reports:
Can you please help me to solve this issue? Probably I'm missing something I can't see to set this relationship.
Thanks in Advance for you Useful Help;
WGAP75
@Anonymous
BLANK values can cause this. (and checking the number of unique values and rows is not necessarily a confirmation:
one table can have ABC, another BCD - both have 3 rows, both have the same number of unique values and yet the values are different...)
To solve this you can create a bridget table between the two conflicting tables including all unique values from both the tables you are trying to create. You can create a new table with:
New bridge table =
VAR ValuesT1 = VALUES(Table1[Column])
VAR ValuesT2 = VALUES (Table2[Column])
RETURN
DISTINCT(
UNION(ValuesT1, ValuesT2)
)
Then create a One-to-Many relationship between this bridge table and the other two tables.
Proud to be a Super User!
Paul on Linkedin.
Hi @Anonymous ,
Just a thought, what if delete the relationship between 'people lookup' and 'N-1 reports'.
Best Regards,
Jay
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