Fabric - rows per table limitation

"Is it correct that direct lake rows per table limitation means that I can exceed the limit but that it then will use DirectQuery? Is it the same for lakehouse and warehouse?"

"Are there any limitations on semantic model size?"

Yes, see the answer from AndyDDC

"what is the suggested method to list numer of rows and size per table in lakehouse/warehouse?"

"What is Direct Lake mode size?"

Many tools can count the rows in the table. The most common approach is probably to use notebook or SQL endpoint to do this.

Regarding how to calculate model size, check out the "Memory footprint" section of this blog post:

https://data-mozart.com/50-shades-of-direct-lake-everything-you-need-to-know-about-the-new-power-bi-storage-mode/

Also check out this blog post, I think you can calculate the direct lake semantic model size in a Notebook: 

https://fabric.guru/calculating-and-reducing-power-bi-dataset-size-using-semantic-link

I think the size of a direct lake semantic model depends on how many columns are cached into Power BI Memory. So I think the size of a direct lake semantic model will depend on which columns are being used ("warm", i.e. loaded into the Power BI service's (Fabric's) vertipaq engine's memory).

There are no row limits anywhere. Fabric is all consumption based - the more you use the more you pay.

Hi joakimfenno the direct lake document has the row limits and model sizes per Fabric SKU (about half way down the document in a table)

https://learn.microsoft.com/en-us/fabric/get-started/direct-lake-overview#fabric-capacity-guardrails-and-limitations

eg F64 allows for 1.5billion rows in a table and respects direct lake, exceeding this row limit will cause a fallback to direct query 

table limits will be the same for lakehouse sql endpoint and warehouse 

You can use mssparkutils or powershell modules, for example

Getting the size of OneLake data items or folders | Microsoft Fabric Blog | Microsoft Fabric

Hi joakimfenno ,

Did the above suggestions help with your scenario? if that is the case, you can consider Kudo or Accept the helpful suggestions to help others who faced similar requirements.

Regards,

Xiaoxin Sheng

we made some tests and compared a table of 300M rows with one of +300M rows
direct lake mode could not be used for the second one
some of the descriptions below are in swedish but you should be able to understand what teh tables show

300M (for F8 capacity in our case) is not a hard limit for storing but for consumption it is significant limitation