Which is the heaviest, one large file (600k rows) or many small ones?

[Anonymous]

Hello, 

I've just gotten a job at an organisation that is relatively new to Power BI and I am picking up where my advisor left off. 

He was new to the platform and to make things easier for him, he had made one huge excel document with all the data from many many different ones. It is now a 600k rows x 5 columns. Everything just have a value, a label (such as "quantity") and who did what.

While I'm buliding this model, the program runs very slowly (5-6 seconds to change tab and 1-2 seconds to select something). My question is this: is it so slow because of the huge document or is it because my hardware (which is provided by the company) is lacking? 

[amitchandak · Accepted solution]

@Anonymous , 600K is not a big number with 5 columns. But have you created a start schema with Date and any other dimension you have.

Also, check how much memory power bi is taking. Sometimes other process takes too much of the memory

https://www.sqlbi.com/articles/the-importance-of-star-schemas-in-power-bi/