Need help: Merging multiple reports data into one central database in PowerBI service

HI Tutu_in_YYC ,

1.Dataflow uses Power BI internal storage to store data by default, and does not enforce Azure Data Lake Storage Gen2 access.Gen 1 you only need to have Pro access or PPU access, but you encounter (store large amounts of data or cross-service integration), only to use to Azure Gen 2, for most of the For most scenarios, the built-in storage is sufficient.

Configure and consume a dataflow - Power BI | Microsoft Learn

2. Regarding the DAX computation of Dataflow data after it enters the semantic model, your understanding is absolutely correct! Dataflow is responsible for providing the cleaned and processed data to the semantic model. In the semantic model, you can centrally create and manage DAX metrics, and these metrics can be reused by multiple reports. If you update DAX calculations in the semantic model, all reports that rely on the model automatically apply the updates, simplifying the management process.
3. Dataflow is well suited to handle data from SQL Server and Excel files. Its ability to unify the processing of this data makes it suitable for building centralized data models. If you don't need to use Azure Data Lake Gen2, Dataflow doesn't come at an additional cost and you can use the storage built into Power BI.

Hope it helps!

Best regards,
Community Support Team_ Tom Shen

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