Online database storage

A simple solution required to provide the following features

1) a hosted server (contabo/aws etc) with capacity to hold up to 50m consumer records
2) upload functionality with field mapping (the data uploaded will be in a csv format), but not always containing the same fields as data already in the db. So, an uploaded field must be mapped to a current field in the db, or create a new field (or ignore entirely)
3) simply query function to count records, export and update a field to identify the number of time each record has been exported.
4) user/pass/keyfile access

No auto bids from developers pasting pages of 'previous work' thats not relevant. I'm not looking for a 'beautiful' system as this will be used internally only, quick, cheap and made quickly matter most to me. If you've read this far, please start your bid/proposal with the word 'database', so I know you're a genuine freelancer.

Thanks