Error using Power BI Direct Query Connection to Dremio

Hi all,

While using direct query option I am getting the below error. I am accessing a dataset (which has no null values) stored in the home folder in Dremio.


In Power BI, When I go to edit queries and click on the source it shows the following message

Is there a way to avoid this? Since I will the description column is the issue.

Is there a way to connect to only the dataset via Direct Query?


This is the first error i was referring to ->

Hi Suraj,

This is a known issue we have encountered with the latest version of Power BI. We are investigating the source of the problem and will update you when it is fixed. In the mean time, are you able to work on an older version of Power BI? If so please, let us know if that continues to give you issues.


Thanks for the clarification. I used the December edition of Power BI Desktop. It is working fine.


Hi Suraj,

The ODBC driver has been updated to fix this issue with the latest versions of Power BI. If you would like to use a newer build of Power BI, please head over to Dremio’s download page to get the latest ODBC driver.

Let us know if you run into any further issues. Thanks.


Just a note. If you are doing a fresh install of PowerBI (as opposed to an upgrade from a previous Power BI version), you may encounter an issue where Power BI cannot find the Dremio Connector. This is a known issue we are tracking with the March build of Power BI. A workaround for this issue for now is to copy the Dremio.mez file from “C:\Users[USER]\Documents\Microsoft Power BI Desktop\Custom Connectors” to “C:\Users[USER]\Documents\Power BI Desktop\Custom Connectors”.

I’ve just tried the upgrade from the December 2017 release of PowerBI (which works well with Dremio), I still have the “We cannot convert the value null to type Table” error.

My setup:
OS = Windows10
PBI version : 2.56.5023.1021 64-bit (March 2018)
ODBC connector = dremio-connector-odbc-
This is just for your information, I can live with the older PowerBI which is doing what I need.


Hi Romain. Please run the BISetup.exe installer that came as part of the new ODBC package. It should repackage a new mez file in your custom connector directory. Please let us know if this does not work as there may be a permission issue regarding your PBI custom connector directory. We can investigate further if running BISetup.exe doesn’t work. (You can find this executable easily by just searching for it in the Windows search bar)

I can’t find any Biinstall.exe file (I rather have a BISetup.exe in C:\Program Files\Dremio Connector). However looking at it’s modification date (06NOV17), I wonder if it is really the latest version.
I have a Dremio.mez file in C:\Program Files\Dremio Connector\Microsoft Power BI whose mod date is 24MAR17

Is the new ODBC connector supposed to be installed in another folder ?

Hi Romain,

Sorry, I meant BISetup.exe. These file timestamps don’t seem correct. Are you sure these files are from the driver you downloaded at ?

Could you ensure that when you install the ODBC driver, you check the box for Power BI. Subsequently, you can confirm the timestamp of the mez custom connector file being used by looking in [My Documents]\Microsoft Power BI Desktop\Custom Connectors (in PBI versions prior to the March 2018 build).

No I’m not sure the files come from the latest download as I did not run uninstaller.exe in C:\Program Files\Dremio Connector before running dremio-connector-odbc- I got no error message, but have the files been properly replaced ?

I thought I got part of the answer looking at the details of the ODBC connector install : I should have mentionned that my regular windows account (the one I use to launch PowerBI) doesn’t have admin rights. Hence I have another account (not connected to the network) which I use for the install. As a consequence, the mez file is created in C:\Users[My_admin_account]\Documents\Microsoft Power BI Desktop\Custom Connectors.
I thought I could solve the issue by replacing C:\Users[My_regular_account]\Documents\Microsoft Power BI Desktop\Custom Connectors\Dremio.mez by C:\Users[My_admin_account]\Documents\Microsoft Power BI Desktop\Custom Connectors\Dremio.mez, but it doesn’t work. I also tried giving my regular account admin right for the install, reinstalling just the ODBC connector and the BISetup, but it doesn’t work either.
I’ll try a complete reinstall from scratch when I have time(restarting the PC after the uninstall of both PBI and Dremio Connector, ) I’ll keep you posted

With a fresh install, everything works as expected now.
Thanks for your help !

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