> We're in a stage where I need to implement a mechanism to prevent the
> data modification.
>
> I'm thinking on 'Digital Signatures' (maybe RSA) in each row. If
> there's a modification, the signature doesn't verify.
Like all such solutions, the key (lame pun intended) is how to do you
manage the keys? Obviously, when the digitally signed data is inserted,
the private key must be accessible. If you then do an update and also
have access to the keys, then new digitally signed data would be there.
Is there no way for your application to ensure that once data is
inserted, it cannot be changed?
You can also grant database access with just SELECT,INSERT permissions
so that an UPDATE and DELETE are not allowed.
We store lots of digitally signed data as BLOBs in PG, but control this
at the application level since it's the one that has access to the
private key, and our application has no UPDATE/DELETE calls.
Good luck,
David
