data mapping

[Anonymous]

I have two tables with identical columns: one table (t1) holds historical data updated monthly through the server, and the other table (t2) contains daily updates from an Excel file. I aim to combine these tables in Power BI without using the append operation, as it leads to a lengthy 2 to 3 hours refresh time. Kindly recommend a method to accurately map these two files in Power BI, addressing the performance concerns associated with the append operation.

[Anonymous]

Hi @Anonymous ,

If you want to reduce the refresh time and increase the reliability of the refresh, check if incremental refreshes are suitable for your scenario.
Incremental refresh for files in a Folder or SharePoint

With incremental refresh, the service dynamically partitions and separates data that needs to be refreshed frequently from data that can be refreshed less frequently. This can significantly speed up data refreshing and reduce the amount of data that has to be transferred between Power BI and the data source.
Incremental refresh for semantic models and real-time data in Power BI - Power BI | Microsoft Learn

Best Regards,
Gao
Community Support Team

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