Object reference error when using Count-Distinct on BigQuery data

[RBlanquet]

I am getting the following error when trying to use a Count-Distinct on a BigQuery table:

OLE DB or ODBC error: Object reference not set to an instance of an object.

I have no problem running another calculations on the said table, always connected via DirectQuery, but whenever I try to use a DISTINCT on any column with or without null values.

In an older version of Power BI I don't have this problem as it only started happening last week after update. I also noted that a recent update (July 2025 QFE 3 - Version 2.145.1602.0) released a similar fix to my problem, although related to Snowflake.

Any thoughts on a fix?

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Attached error log from Power BI Desktop for reference:

Feedback Type:
Frown (Error)

Timestamp:
2025-08-26T14:14:47.1365621Z

Local Time:
2025-08-26T08:14:47.1365621-06:00

Session ID:
6a403e7d-d470-44fe-974e-a84744c66efe

Release:
August 2025

Product Version:
2.146.1026.0 (25.08)+fb98ab832373de81dccd5c01cd96306a48477556 (x64)

Stack Trace:
Microsoft.Mashup.Host.Document.SerializedException
at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
at Microsoft.Mashup.OleDbProvider.DataHost.NonBufferingMashupEvaluator.MashupEvaluation.OnEvaluationComplete(AsyncResult`1 result)
--- End of stack trace from previous location where exception was thrown ---
at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
at Microsoft.Mashup.OleDbProvider.MashupCommandEvaluation.get_PageReader()
at Microsoft.Mashup.OleDbProvider.TracingRowset.Microsoft.OleDb.IEvaluationResultSource.WaitForResults()

PowerBINonFatalError:
{"AppName":"PBIDesktop","AppVersion":"2.146.1026.0","ModuleName":"","Component":"Microsoft.Mashup.OleDbProvider.DataHost.NonBufferingMashupEvaluator.MashupEvaluation","Error":"Microsoft.Mashup.Host.Document.SerializedException - Microsoft.Mashup.Evaluator.Interface.ErrorException","MethodDef":"OnEvaluationComplete","ErrorOffset":"","ErrorCode":""}

OS Version:
Microsoft Windows NT 10.0.22631.0 (x64 en-US)

CLR Version:
4.8 or later [Release Number = 533320]

Peak Virtual Memory:
70.9 GB

Private Memory:
775 MB

Peak Working Set:
919 MB

IE Version:
11.1.22621.0

User ID:
600d6075-a6c8-4689-bf9c-4b31b7013e66

Workbook Package Info:
1* - en-US, Query Groups: 0, fastCombine: Disabled, runBackgroundAnalysis: False.

Telemetry Enabled:
True

Model Default Mode:
DirectQuery

Model Version:
PowerBI_V3

Enabled Preview Features:
PBI_googleBigQueryAdbcVersionEnabled
PBI_scorecardVisual
PBI_setLabelOnExportPdf
PBI_oneDriveSave
PBI_oneDriveShare
PBI_odspSaveBackgroundUpload
PBI_modernOfficeFilePicker
PBI_useModernPublishDialogs
PBI_gitIntegration
PBI_tmdlInDataset
PBI_directLakeRemoteModeling
PBI_directLakeOnOneLake
PBI_newCard
PBI_buttonSlicerAuthoring
PBI_daxInlineCopilot
PBI_aiNarrativesVisual
PBI_visualCalculationsAuthoring
PBI_tmdlViewToggle
PBI_copilotUnifiedTooling
PBI_UserInstalledVerticaODBCDriver
PBI_sqlDbNativeArtifactsOnDesktop

Disabled Preview Features:
PBI_shapeMapVisualEnabled
PBI_SpanishLinguisticsEnabled
PBI_qnaLiveConnect
PBI_metricsArtifactsOnDesktop
PBI_b2bExternalDatasetSharing
PBI_enhancedTooltips
PBI_onObject
PBI_publishDialogsSupportSubfolders
PBI_enhancedReportFormat
PBI_advancedSlicerTypeList
PBI_textSlicer
PBI_qnaImproveLsdlCopilot
PBI_UserInstalledNetezzaODBCDriver
MashupFlight_EnableOracleBundledOdacProvider
PBI_dataFunctionActions

Disabled DirectQuery Options:
TreatHanaAsRelationalSource

Cloud:
GlobalCloud

DPI Scale:
100%

Supported Services:
Power BI

WebView2 Runtime Version:
139.0.3405.111

WebView2 SDK Version:
1.0.2365.46