Long delay while refreshing the tables in Power BI Desktop

[SushmaReddy]

Hi,

I am facing an issue while changing the source files in Power BI desktop with same data.when i tried to change the source file it is taking long refresh time but when the data is copied from new file to old file then it is working fine.Here the source is Excel files

Please explain the reason behind it...Thanks in advance...

[lbendlin · Accepted solution]

Power Query has thrown away all meta data information and is recreating it from scratch, resulting in the dreaded "Evaluating..."  time sink.

Try not to change your data sources too much.