Hi! I've downloaded your latest update to EF Core 2.1 after reading your blog. However, I don't think this actually works as intended. I was able to make the solution appear to work after a minor change in the UploadFiles method of the FilesUploadController due to Path.Combine seeing the second argument as a full path and then ignoring the first argument:
var fileName = Path.GetFileName(ContentDispositionHeaderValue.Parsefile.ContentDisposition).FileName.ToString().Trim('"'))
What I noticed is that the extension method SaveAsAsync only streams the file to the folder provided in the configuration directly using System.IO. It has nothing to do with SQL Server and FileTable. After loading the file to the directory and being able to download it through the MVC UI, there is no entry however in the WebApiUploads table.
I hope we have a chance to discuss this.