I've deployed an ethereum blockchain workbench with a custom blockchain contract. I'm able to create transactions via the workbench ui and I've also written a custom mvc app that is integated to present a custom ui that I am using to create new transactions. All of this is working perfectly,. My question is with regards to the blockchain sql database. I am able to use ss object explorer to view and update the data in the database including the deletion of contract instances. Isn't the purpose of having a blockchain to prevent the external manipulation of the data or is the data editable only because the smart contract is deployed to the workbench?