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Unable to Fold Query using MariaDB Direct Query Adapter for Power BI

I installed the mariadb-connector-ODBC-3.1.20-win64 ODBC connector and used the MariaDB connector in Power BI.

Then I used the Direct Query mode to connect to the database. I was able to pull some of the data from column (containing text) in the database's table but while trying to get the count of another column (containing numbers) I ran into 'ole db or odbc error: [Expression.Error] We couldn't fold the expression to the data source. Please try a simpler expression..'. Now, getting count should be a simple expression and the number of rows is also shy of a few hundred thousand. I even tried extraction of that particular column only in Power Query but the same error. (I was using credentials with appropriate access)

Now, I tried the same with Import mode and it worked flawlessly. But I need to implement Direct Query mode to leverage near real time reporting.

Additionally, with DirectQuery some relationships would show a cardinality of Many to Many while they were in fact they were observed to be Many to One using Import mode.

Also, the 'View Native Query' option is greyed out from the very first 'Source' step in both DirectQuery and Import mode.

Any guidance on how to troubleshoot this would be appreciated.

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