Relationship building crashes Power BI when validation is skipped, "both" cross filter detection

[rlooney]

We have duplicated this issue with multiple ODBC drivers and the native SQL Server driver.  It appears to be unrealted to the data source and instead a generic problem with relationship building when cross filter detection is set to "both" in Power BI Desktop (Nov 2018 release tested, but previous releases have the same issue as well).

Steps to duplicate:

1) Connect to data source

2) Load a couple tables (ideally tables that don't already have relationships)

3) Create a relationship between 2 tables.  2 keys about this...

  ++ You must select "Cross Filter direction = both". 

  ++ You must click "OK" while the dialog still says "Validating...".   (use a data source on a slow network if possible, or otherwise slow down your data source at this point)

4) Power BI will present the above Validating Relationship dialog.  Hit "Skip" while this is still present.   SQLDUMPER is called, and Power BI crashes.

 ++ Note this only happens if you've selected "both" for cross filter detection.  "single" works just fine.

With tracing turned on, you can see this exception in the logs when it happens...

ExceptionType: System.IO.EndOfStreamException

...

Message: Unable to read beyond the end of the stream.

StackTrace:

 at System.IO.__Error.EndOfFile()

   at System.IO.BinaryReader.FillBuffer(Int32 numBytes)

   at System.IO.BinaryReader.ReadInt32()

   at Microsoft.Mashup.Evaluator.MessageSerializer.Deserialize(BinaryReader reader)

   at Microsoft.Mashup.Evaluator.StreamMessenger.Read()

Since the app fully crashes, I can't send a frown/traces but would be happy to provide more details to get this issue cleaned up for our customers.

[v-qiuyu-msft]

Hi @rlooney,

Do you import data from SQL database or connect with DirectQuery mode? If it's import mode, please share your pbix file with us if possible. You can upload it to your Onedrive and send the share link to me via private message. 

Also you can try to update your Power BI desktop to the latest version 2.64.5285.701 then test again to see if the same issue occurs. 

Best Regards,
Qiuyun Yu 

[rlooney]

Hi @v-qiuyu-msft -

I downloaded 2.64.5285.701 and was still able to reproduce the issue consistently.

Both tests I did (ODBC and SQL Native connector) were using DirectQuery mode.  I don't expect import mode will have this issue as there should be no lag during the relationship build since the data is already local.  I tried to test, but I can't ever see the "Validating. Relationship" when in import mode because of the lack of lag to really test it.

Thanks,

Bob

[v-qiuyu-msft]

Hi @rlooney,

There is a new desktop version 2.64.5285.741, if the issue persists with this version. I would suggest you create a support ticket to let engineers look into your environemnt. 

Best Regards,
Qiuyun Yu 

[rlooney]

It seems different now.

Before, it would crash as soon as I hit "Skip" in the Validating Relationships dialog.

Now, it doesn't crash right then, but as soon as you do something else it crashes (building a second relationship or going into edit the query).

I can still find this error in the logs:

"Message: Unable to read beyond the end of the stream."

However, I also see this error now in the logs now which might relate to the change in behaviour:

"Message: A Task's exception(s) were not observed either by Waiting on the Task or accessing its Exception property. As a result, the unobserved exception was rethrown by the finalizer thread."

I will submit a support ticket to see if that helps resolve this.