Forum Discussion
XLSX file 10MB, but Power Query loads 100MB into Power Query
Hi, My file size is only 10MB, but when I load it into Power Query, it seems to be loading 10 times the file size. I do not have any tables or pivot tables in the dataset and am wondering why...
Hi Anonymous ,
I believe this is the problematic step:
#"Filtered Rows2" = Table.SelectRows(#"Changed Type1", let latest = List.Max(#"Changed Type1"[Data Date]) in each [Data Date] = latest),In there, you're referencing the previous whole table for each row in your table.
This is where buffering usually helps.
If your source table is very large, you can buffer the list whose Max you are retrieving in a previous step like so:
BufferedList = List.Buffer(#"Changed Type1"[Data Date]),
#"Filtered Rows2" = Table.SelectRows(#"Changed Type1", let latest = List.Max( BufferedList ) in each [Data Date] = latest),
You can find more performance tips on my blog here: Speed/Performance aspects – The BIccountant
You are an absolute star.
I have been grappling with this problem for a week now and this solved it.
Take the rest of the day off 😊