Forum Discussion
Inconsistent Data After Refresh - Merge Query Issue (?)
ImkeF , I did some brief testing by adding Table.Buffer on the fact table and remove the Table.Buffer in the dimension tables.
In Power BI Desktop, it seems to work fine, i.e. data does not get out of whack after refresh there.
However, the issue still persists when I publish to PBI Service and refresh there.
Basically, what I am trying to do is following this approach of modelling.
https://radacad.com/build-your-first-star-schema-model-in-action-power-bi-modeling-basics
Since the issue seems to be caused by PowerBI/PowerQuery incorrectly retrieves the Index field values after Merged Queries transformation in the fact table, I removed all the relationships which use these key/index fields.
Instead, I now use the concatenation of multiple fields to form the keys on each tables and join them in the Relationship.
By doing this, no issue with data getting out of whack - PBI Desktop and PBI Service data refresh seem fine.
Really disappointing something basics like this cause lots of issues and wasted lots of time, especially because I know some PBI experts like Reza (as above) and others promote this approach of data modelling..
Hi Anonymous ,
I can understand your frustration.
I'm pretty sure this is a bug, would have appreciated if you would have reported it.
Don't understand why you removed the buffer from the Dim-Tables. I would strongly recommed to keep them in, so having a buffer on both tables: Fact and Dim.
Posted it as an issue as suggested in here.
Hi bidax, any news from Microsoft about that bug? Did you find some alternative solution to avoid inconsistencies in surrogate keys?
I'm experimenting the same issue here, just to have some fresh reference on this issue.
Thank you.
