We couldn't fold the expresion to the data source (NO DAX)

[NicolasLJ]

Hi,

I created a direct query data set by connecting to a Postgresql database with an SQL statement :

There is no transformations :

I tried a simple visual with a table, all fields are working except one (Hours field) :

Any help ? 🙂

[hi_world]

Hello, 
Did you find a solution ?

I find the same error.
except that for my part, if I open my dataset with a PowerBI version of 2023 it works well.

[NicolasLJ]

I already found your article, but in my case there is absolutly no Dax, no transformation and the source is a simple query. All columns from the result of my query works when I add them into a simple table visual except one, I really don't understand...

I just tested creating a view on the database side and not adding any queries or dax or any transformations, just a direct query on a simple view... same error. 

[v-rongtiep-msft]

Hi @NicolasLJ ,

You can do some pretty complex things in the Power Query Editor and in DAX and the error message above is the error you get when Power BI admits defeat and says it can’t translate a DAX query generated by a visual on a report into a query against your data source. 

More details: Chris Webb's BI Blog: Understanding The “We Couldn’t Fold The Expression To The Data Source” Error I...

PowerBI direct query connection to PostgreSQL error. OLE or ODBC error: [Expression.Error] We couldn...

OLE DB or ODBC error: [Expression.Error] We couldn... - Page 3 - Microsoft Fabric Community

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