In addition to Coda’s really secure and very reliable infrastructure, it’s not unreasonable or imprudent to consider maintaining an off-Coda copy of your data. Using the Coda API you can map a scripting process from say - G-Suite - to capture the latest state of every table in every document.
I was working on a unified full-tech search index for a client and I realised it was a pretty short leap to harvest all tables/fields/rows into a JSON document that stored securely in Google drive folders that are not shared with anyone once a day.