Must Blockchain be a slow and expensive Database? Cardano is going to rewrite History.
For a long time, it has been said that blockchain is a slow, expensive, and ineffective database and that it cannot be used for anything other than cryptocurrency. In the article, we will explain why a database cannot be a blockchain and that blockchain cannot be necessarily slow or expensive unless it is intended to be. PoS network consensus can change it and Cardano builds one.
The database is not a blockchain
Let’s start by refuting one myth. The database will never be blockchain. To keep it simple, a database is a space for storing things. Your employer probably has a database and stores digital information about you. Every e-shop has a database keeping information about all goods, orders, customers, etc. Blockchain is a ledger. You can imagine the ledger as a balance sheet or an account book. It is a collection of things of the same kind and there is information about ownership. A Digital ledger is able to keep a track of history and it is possible to get the latest valid state. As a user of a cryptocurrency wallet, the ledger can provide information on how many coins Alice or Bob owns.
It is possible to create, read, update, and delete (CRUD operations) data from a database and all operations are fast and highly scalable. This is possible since there is only one node or server with the database and no network consensus is required. Thus every operation happens immediately. Blockchain is immutable so it is only possible to append new data without the possibility to rewrite history. Thus the history is always fully auditable. Blockchain is able to keep all transactions. Thus it is possible to go through all historical transactions stored in the very first block of the blockchain up to the end of the blockchain. Once the lastly added block is read you can see the current state of the ledger.
Read more about the differences between database and blockchain: