DB2 DirectQuery

[robarivas]

I receive the following error message anytime I drag any field onto the canvas from a DirectQuery IBM DB2 dataset. Is there something I'm doing wrong? How can this be resolved?

OLE DB or ODBC error: [Expression.Error] We couldn't fold the expression to the data source. Please try a simpler expression.

[v-frfei-msft]

Hi @robarivas,

I can reproduce this issue in the power BI desktop July release Version: 2.60.5169.4101 64-bit (July 2018). I will report this issue internally and post back once I get updates.

Regards,

Frank

[robarivas]

Thank you @v-frfei-msft. I look forward to any updates.

[robarivas]

Hello @v-frfei-msft. Just an FYI...I installed the newest version (Version: 2.61.5192.541 64-bit (August 2018)) and the problem remains unfortunately. 

[v-frfei-msft]

Hi @robarivas,

This is a known issue. The fix is currently in code review.

Regards,

Frank

[v-frfei-msft]

Hi @robarivas,

Tentative ETA is the November Release.

Regards,

Frank

[robarivas]

Hello @v-frfei-msft

On the latest November 2018 release [ 2.64.5285.741 (18.11) (x64) ] the problem remains.

OLE DB or ODBC error: [Expression.Error] We couldn't fold the expression to the data source. Please try a simpler expression.

If I do something extremely basic (like distinct count of the primary key field) then it works but just about anything more than that gives the error above.

Would love to know a best guesstimate as to when I might be able to use DirectQuery. Thanks!

[Anonymous]

Hi,

Same for me.

We are currently trying to replace existing BI components with this feature and evaluate it.

As for now, this is just not working.

Thanks for ur help!

[v-frfei-msft]

Hi @robarivas @Anonymous @Spartachris,

The issue should be fixed now. As I made a test just now using the latest version of Power BI desktop 2.66.5376.1681. It worked well.

If any question ,feel free to let me know please.

Regards,

Frank

[robarivas]

Hello @v-frfei-msft It does no longer appear to generate an error (although I've done only the tiniest amount of testing). However, the performance is exceptionally slow. I'm using the IBM DB2 connector running off of the .NET driver (not the IBM Driver). Also, the instance of DB2 I'm connecting to is on z/OS mainframe. I'm wondering if your testing was completely equivalent to mine. I know that for Importing data (not DrectQuery) we are having performance problems with the DB2 connector, so much so that we've had to revert to the ODBC connector just to keep our reports from timing out during refreshes on the Power BI online Service. Could whatever problem is going on with the DB2 connector also explain the poor speed when using DirectQuery?

[robarivas]

Hello @v-frfei-msft. Thank you for the follow-up!

[Spartachris]

Hi, I'm experiencing the exact same issue in Power BI September release with an AS/400 system (IBM DB2 7.3) source. Just wanted to check in and see if the fix is still on track for November?