Data Grouping Breaks Query

[bradbel]

Not sure if this is the correct place to ask - but I have a query set up to pull data from another workbook and when I try to refresh with grouped columns Excel completely freezes and I have to force quit. In the same table, changing nothing but ungrouping columns, there are no issues with refreshing the query. When refreshing with grouped columns, Excel completely freezes whether the columns are expanded or collapsed.

This seems odd as I can imagine many people have large datasets with multiple columns they may want to have hidden sometimes. 

[bradbel]

Thank you for your quick response - I will look into utilizing PowerPivot. I only recently started using the Excel power query toolset so much of this is new to me. We currrently have about 10k rows of data stored in a table, and we rely on about 20 columns of formulas to concatenate the data into diferent categories to view in various ways for reporting (Basically just viewing different general ledger accounts in different departments). So, we use data grouping to easily collapse these columns as we typically don't need to analyze them. If you have any additional advice for setting up Power Pivot, I'm all ears. Power query has already transformed the way we're able to efficiently report on data so more improvement is certainly welcome.

[ToddChitt]

Ask yourself this: WHY do I want to do a GROUPING of my data? Especially in light of the fact that Excel does a nice job with Pivot Tables that does the grouping for you, and gives you options not available in Power Query.

How many records are we talking about? I have sucessfully queried several million into an Excel PowerPivot model (NOT a sheet), then left it up to the users to do their own grouping in a Pivot Table.