Snowflake DirectQuery incredibly slow on Power BI Desktop, yet works fine in Power BI Service

[tahga]

It is near impossible at the moment to develop direct query reports on Snowflake with Power BI Desktop. I'm running the latest version of Power BI Desktop (9/2019) and Snowflake ODBC driver (2.19.14.00). Visuals take ages to load, refresh is stuck on "Evaluating..." and "Waiting for other queries..." for tens of minutes. I searched for similar issues in the past and tried all the suggested resolutions, e.g.

• Clearing PBI Desktop cache & rebooting
• Playing with the data load settings:
• Updating the Snowflake ODBC driver and reducing logging settings from regedit.

None of these seem to work. We also tested with a colleague's computer with the same results. The query logs from Snowflake show that Power BI does run queries into Snowflake and those are completed in seconds.

The strange thing is that, once you wait it out and manage to develop and publish a direct query report into Power BI Service, it works fine with the gateway and the same ODBC driver. So this seems to be a Power BI Desktop specific issue.

[v-diye-msft]

Hi @tahga 

Make sure you enable parallel loading tables.

And verify your Power Query to see if there's any Query Fold issue.

Not Folding; the Black Hole of Power Query Performance

If there's no issue on the query, please fetch the Fiddler Trace and create a support ticket for deep analysis. 

[tahga · Accepted solution]

Thanks for your response @v-diye-msft. I actually had it enabled at first and just tried disabling all the options.

Turns out the slowness was caused by these automatically added parameters in Power Query:

[CreateNavigationProperties=null, ConnectionTimeout=null, CommandTimeout=null]

After removing these, the performance is back to normal.

[PAPutzback2]

I went into the advanced editor and I don't see those paramters. I don't see them under parameters either. I also have the Parallel loading of tables enabled.