Forum Discussion
Dataflows Gen2 cannot access Lakehouse Files — missing OneLake internal provider
Hello pbiadminjenhill,
What you’re seeing is expected behavior based on the current design of Dataflows Gen2 in Microsoft Fabric.
Dataflows Gen2 connects to a Lakehouse through the SQL analytics endpoint, which exposes Delta tables only. It does not surface the Lakehouse Files folder structure. As a result:
The Lakehouse connector shows tables, not /Files/...
File paths are treated as external sources and may prompt for a gateway
Combining Parquet files directly from Lakehouse Files isn’t supported
Incremental refresh applies to table sources, not raw file paths
This is a product capability boundary, not a tenant, region, trial, or GoDaddy limitation.
If you need to transform Parquet files stored in Files, first materialize them as Delta tables (via Notebook or Pipeline). Once the data exists as a Lakehouse table, Dataflows Gen2 can access it and support transformations and incremental refresh.
Thank you for the suggestion. I will definitely try this solution. I do have the option of bringing the file in as csv, avro, or parquet. Should I be thinking of bringing it in one of those formats so that incremental refresh could work or are none of those options going to work for incremental refresh? If not incremental refresh how about a full rewrite. The amount of data is not too crazy - overall across all tables maybe 500k rows? Thank you so much for your advice!
Hello pbiadminjenhill
Unfortunately Delta tables (i.e., files stored in Delta format, is what Dataflow Gen2 expects to use for Incremental Refresh - csv/avro or parquet won't work!
This is because Incremental Refresh with Dataflow Gen2 works on Query Folding, and those file types don't allow query folding.