Is it possible to protect data in databases from the developer, ITS?

Question

Database

Good afternoon!
There are two programs based on the 1C platform, one has a file base, the other has a PostgreSql DBMS. There is no own administrator and developer, everything is outsourced. Legally, the necessary documents have been signed to protect personal and other sensitive data, but in fact, the Contractor has full access to the data.
Is it possible to secure data in this regard? For example, in order for the Contractor not to see the content, he could not copy either the database or backup copies.

Answer 1

give the developers a backup with the cleaned data. With admins it's more difficult - get your own, 100% loyal.

Answer 2

You can't protect yourself from the administrator :) This fact is not understood by many managers - Quis custodiet ipsos custodes? (Who guards the watchmen - lat.) No means have been invented to protect against someone who, in fact of his work, should have access everywhere. You have to be a class above him to see the bookmark he made, but then why do you need an admin at all?
It's just enough for developers to give out old, outdated data.