Query Folding in Dataflow ignored by pbix

[timhopson]

Hi, 

I have a dataflow that appears to support query folding, however, when I use the dataflow in a pbix, query folding doesn't happen and the whole table is imported, which is very large.

In the dataflow, I can view the DataSource Query (see the dataflow applied steps below). Which makes me think it's set up for Query Folding. There is also the green icon with the lightning flash.

This is what I see when I use the dataflow as a data source in my pbix.

I've tried adding a custom function View.NativeQuery and setting [EnableFolding=true] but it didn't appear to help.

I'd be grateful for any help on this.

regards, Tim.

[KNP · Accepted solution]

Hi Tim,

I'm a little confused about what you're expecting to happen when you connect to the Dataflow in the PBIX file.

Also, I have questions.

1. Is the Dataflow in a Premium or PPU capacity?
2. Is the 'Enhanced compute engine' turned on for the Dataflow?
3. Are you using the PowerPlatform.Dataflow connector in the Dataset?
4. Is the table you are pulling into the PBI dataset from the Dataflow a computed table?

If any of these criteria (there may be others) are not met, chances are, the query folding won't happen.

If you've set the Dataflow table as import mode in the dataset, query folding will be largely irrelevant without filters or incremental refresh setup on the Dataset. 

Just because the 'View Native Query' is greyed out, it doesn't mean folding isn't happening. 

Hopefully some of this is helpful. Let me know if you have questions.

[timhopson]

Hi KNP, 

Thanks for the reply. I was about to answer YES to all your questions when I realised that Enhanced Compute Engine wasn't turned on. Once I turned this on and refreshed the dataflows, the View Native Query became available. I have previously had this setting turned on and forgotten about it when I deleted the dataflow and re-created it.

Thanks again for your help.

regards, Tim.