I wish to build something like proof of authenticity on blockchain.
I thought of using this approach: storing the hash of data in ethereum blockchain and the data itself in some storage elsewhere.
Let's say it's an article we are talking about. If one needs proof that this article existed at some point of time, he can use the hash algorithm to generate hash from the article stored in whatever database/datastorage and compare it with the hash stored in blockchain.
can someone tell me if this would work. Also, is there a way to change the data data without changing its hash