Power BI refresh failure

[anubhutani]

Hi, 

Yesterday the Power BI refresh failed for my DataSet giving the following Error:

Query execution has exceeded the allowed limits (80DA0003): Query result set has exceeded the internal data size limit 67108864 (E_QUERY_RESULT_SET_TOO_LARGE; see https://aka.ms/kustoquerylimits). [0]Kusto.Data.Exceptions.KustoServicePartialQueryFailureLimitsExceededException: Query execution has exceeded the allowed limits (80DA0003): Query result set has exceeded the internal data size limit 67108864 (E_QUERY_RESULT_SET_TOO_LARGE; see https://aka.ms/kustoquerylimits). Timestamp=2021-05-26T00:39:11.3829208Z ClientRequestId=KPBI;b5a70e3b-7a10-4047-bea3-5a64e5b2ab07;8004d86f-ad63-4945-b936-850b62ddf203;660567fa-5a76-4f42-aa4c-ddc220637713 ActivityId=ea1b2bf5-d299-4314-ae0f-771d079f692c ActivityType=PO.OWIN.CallContext ServiceAlias=DAMPERTEST MachineName=KEngine000000 ProcessName=Kusto.WinSvc.Svc ProcessId=12132 ThreadId=13696 AppDomainName=Kusto.WinSvc.Svc.exe ActivityStack=(Activity stack: CRID=KPBI;b5a70e3b-7a10-4047-bea3-5a64e5b2ab07;8004d86f-ad63-4945-b936-850b62ddf203;660567fa-5a76-4f42-aa4c-ddc220637713 ARID=ea1b2bf5-d299-4314-ae0f-771d079f692c > PO.OWIN.CallContext/ea1b2bf5-d299-4314-ae0f-771d079f692c) MonitoredActivityContext=(ActivityType=PO.OWIN.CallContext, Timestamp=2021-05-26T00:38:55.1595120Z, ParentActivityId=ea1b2bf5-d299-4314-ae0f-771d079f692c, TimeSinceStarted=16223.4088 [ms])ErrorCode= ErrorReason= ErrorMessage= DataSource= DatabaseName= ClientRequestId= ActivityId=00000000-0000-0000-0000-000000000000 UnderlyingErrorCode=80DA0003 UnderlyingErrorMessage=Query result set has exceeded the internal data size limit 67108864 (E_QUERY_RESULT_SET_TOO_LARGE; see https://aka.ms/kustoquerylimits)

The Data source for my Power BI Data Set is Kusto and I think the default limit in Kusto is ~64MB and the size of one my Kusto tables was 94 MB that's why the refresh failed.

These is how I was connecting to my Kusto Data Source:

Source = Kusto.Contents(clusterUri, "YYY"&Environment, null, [MaxRows=10000000, MaxSize=null, NoTruncate=null, AdditionalSetStatements=null]),
XXXX1 = Source{[Name="XXXX"]}[Data],

When I changed the MaxSize to 1GB the refresh worked fine:

Source = Kusto.Contents(clusterUri, "YYY"&Environment, null, [MaxRows=10000000, MaxSize=1000000000, NoTruncate=null, AdditionalSetStatements=null]),
XXXX1 = Source{[Name="XXXX"]}[Data],

My query is, the size of my table was 94 MB for a long time. Why did I see this error just yesterday?

Issue somehow got resolved by changing the MaxSize field but I am not sure I understood the problem correctly. 
 

[v-henryk-mstf]

Hi @anubhutani ,

Generally speaking, when the limit set by default is exceeded, some of the exceeded queries will fail and display "Partial query failed".

Your understanding is correct, you can change the size of the default limit by setting truncationmaxsize and truncationmaxrecords to solve the problem of error reporting.

Here is the reference document link: Query limits - Azure Data Explorer | Microsoft Docs

Best Regards,
Henry

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

[GilbertQ]

Hi @anubhutani 

It would appear that the issue was that the initial query was too large when initially running. When you changed your MaxSize, it then make the result set smaller.