Unable to load the table data in data preview after clicking on transform data in power bi desktop.

Hi Anonymous ,

 If the dataset is large, we have to keep everything simple. For example,When you do joins/appends in Power Query it has to load the entire table into virtual memory. This causes a lot of paging and is very slow.

https://docs.microsoft.com/en-us/power-bi/guidance/power-bi-optimization 

https://docs.microsoft.com/en-us/power-bi/guidance/directquery-model-guidance#optimize-report-designs 

https://www.sqlbi.com/topics/optimization/ 

Best Regards,
Liang
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