speed up the CSV import
I have a frequent need to refresh my data which is only achievable by CSV import. It currently takes around 80 minutes to import almost 16,000 records (4 fields each). I suspect that most of that time is spent deleting the old records, presumably one by one. An alternative approach would be to provide a quick 'delete all records' function or to import only changed records, though I suspect that the latter would take even longer!