Issue with Power BI Relationship Automatically Changing from One-to-Many to Many-to-One

Question

Dear all,I have tried to create a one-to-many relationship in Power BI, but it keeps changing it to many-to-one.I have made sure to mark the date table as a date table, ensured that both date columns are set to the date data type, and verified that there are no duplicates in the date column of the date table. Additionally, I have disabled automatic relationship creation. However, it still keeps swapping the relationship automatically.&nbsp;Is this a bug in Power BI? I need the relationship to be one-to-many, and I also need to maintain a relationship between these tables for further visualization.

danextian · Answer

Hi Anonymous&nbsp;
&nbsp;
It's always been that way. I was also confused when I first encountered it. Regardless of whether it's many-to-one or one-to-many, the relationship always flows from the "one" side to the "many" side in a single-direction relationship. The arrow in the diagram indicates the direction of the relationship flow.

https://learn.microsoft.com/en-us/power-bi/transform-model/desktop-relationships-understand
&nbsp;

deku · Answer

Do you duplicate date in the forecast table?&nbsp;If so this relationship looks fine

anonymous · Answer

i do have duplicates in the forecast table. My point is that i want to set a relationship where first table is date (date column) and forecast (date) as second with relationship ONE TO MANY direction single and it does not allow me and swap it to many to one relationship where table FORECAST takes first and date as second but for graphs i need this relationship to be ONE TO MANY

anonymous · Answer

Hi&nbsp;Anonymous&nbsp;Thank you for reaching out microsoft fabric community forum.
May I ask if you have resolved this issue? If so, please mark the helpful reply and accept it as the solution. This will be helpful for other community members who have similar problems to solve it faster.
Thank you.

anonymous · Answer

Hi&nbsp;Anonymous&nbsp;I wanted to check if you had the opportunity to review the information provided by Deku&nbsp; and danextian&nbsp;. Please feel free to contact us if you have any further questions. If their response has addressed your query, please accept it as a solution and give a 'Kudos' so other members can easily find it.Thank you.

Forum Discussion

Issue with Power BI Relationship Automatically Changing from One-to-Many to Many-to-One

6 Replies

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