As you know we can only do groupby for two columns. Is there any way to groupby more than two columns (in SharePoint 2010)?
Yes you can. There is a blog that can help you with this but you need to use SharePoint Designer.
The main points are:
- It can't be done "out of the box" in the browser
- SharePoint Designer is needed to make the edits
- You need to convert the view web part to a SharePoint Designer Data Form Web Part
- You need a Sort and Group secret
- You need to fix the footer rows
- You need to manually add your totals, averages, counts etc