Creating connection to the model

Hi Anonymous ,

If you encounter this issue when transform data, it is likely to cause query performance issues due to merge and append.Please refer to this thread:

https://community.powerbi.com/t5/Desktop/Transformations-in-Power-Query-Very-Slow-Performance/m-p/584292 

If the report is refreshed, too large models may cause slow loading.For queries for which the source data is not updated often or at all, it makes sense to not have the queries included in the refresh of the report.

https://docs.microsoft.com/en-us/power-bi/connect-data/refresh-include-in-report-refresh 

Best Regards,
Liang
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