We have a client with about 20gs of data in SharePoint. They have a legacy folder sitting on an old Naz box with 500gb of data. This is old documents and will be accessed only occasionally by a single member of staff. They want to put it into SP. I can create a new site collection for this but my question is .... can this much data go into a single library? They will be using a simple folder structure. I have seen the figure of 30 million docs in a library but how does that equate to data.
@Victoria Symons 20GB of data should not be a problem to store in a single document library, provided that the SharePoint site has that much storage allocated to it in the Admin Center.
There is a 5,000 item threshold for list views, meaning that if you have a list that shows more than 5,000 items, performance can become sluggish. There are ways to remedy this or work around it, as explained here.