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ODBC Type Mismatch - no information given

Hello,  I am working on a project in Power BI where we are replacing our datasets on the backed from Excel-generated dummy data to Oracle.  I'm doing this swap by going into the Advanced Query editor and replacing the old excel query with the new Oracle query.   We are working with 4 tables at the moment.  3 of these tables swapped over without any issues.  However, I am continuing to receive this extremely unhelpful error for the remaining table:

"OLE DB or ODBC error: Type mismatch. (Exception from HRESULT: 0x80020005 (DISP_E_TYPEMISMATCH))."


Can someone help me debug this issue?  Others have posted about this on their forum but I have found the solutions they used did not work for me or were not relevant. 


Is there a log file or something where I can find more details about this error?  I need to know the following:

- what column has the type mismatch

- what row the record was in

- what the type of the record was supposed to be in Oracle vs. what Power BI interpreted the type as


It will otherwise be impossible for me to figure out what the issue is.  This is a very large table that is being imported, so manual inspection is not possible.  As far as I can tell, even if I restrict my SQL query to < 100 rows, there are no erroneous values, and everything appears to be the type I expect it/need it to be.  


If I open a new Power BI report and copy this Oracle query into that report, the data set loads in full without any issues.  So I'm assuming that the error has to do with a custom measure I've created?  How can I determine which one?  I have dozens of measures.  This should be contained in a log file somewhere, no?

Community Support
Community Support

Hi, @mgeorgiadis 

Based on your description, you may check supported Oracle versions, Power BI Desktop versions and connection steps as following link.


For further information, you can refer to following links.


Best Regards



If this post helps, then please consider Accept it as the solution to help the other members find it more quickly.

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