How is blockchain different from traditional technologies? | How is Blockchain different from Database?

To understand the difference between a blockchain and a traditional database, it is worth considering how each of these is designed and maintained.

Traditional Databases

Traditional databases use client-server network architecture. Here, a user (known as a client) can modify data, which is stored on a centralized server. Control of the database remains with a designated authority, which authenticates a client’s credentials before providing access to the database. Since this authority is responsible for the administration of the database, if the security of the authority is compromised, the data can be altered, or even deleted.

Blockchain Databases

Blockchain databases consist of several decentralized nodes. Each node participates in administration: all nodes verify new additions to the blockchain and are capable of entering new data into the database. For an addition to be made to the blockchain, the majority of nodes must reach consensus. This consensus mechanism guarantees the security of the network, making it difficult to tamper with.

Integrity and Transparency

A key property of blockchain technology, which distinguishes it from traditional database technology, is public verifiability, which is enabled by integrity and transparency.

    Integrity: every user can be sure that the data they are retrieving is uncorrupted and unaltered since the moment it was recorded
    Transparency: every user can verify how the blockchain has been appended over time

CRUD vs Read & Write Operations

In a traditional database, a client can perform four functions on data: Create, Read, Update, and Delete (collectively known as the CRUD commands).

The blockchain is designed to be an append-only structure. A user can only add more data, in the form of additional blocks. All previous data is permanently stored and cannot be altered. Therefore, the only operations associated with blockchains are:

    Read Operations: this query and retrieve data from the blockchain
    Write Operations: these add more data onto the blockchain

Validating and Writing

The blockchain allows for two functions: validation of a transaction, and writing of a new transaction. A transaction is an operation that changes the state of data that lives on the blockchain. While past entries on the blockchain must always remain the same, a new entry can change the state of the data in the past entries. For example, if the blockchain has recorded that my Bitcoin wallet has 1 million BTC, that figure is permanently stored in the blockchain. When I spend 200,000 BTC, that transaction is recorded onto the blockchain, bringing my balance to 800,000 BTC. However, since the blockchain can only be appended, my pre-transaction balance of 1 million BTC also remains on the blockchain permanently, for those who care to look. This is why the blockchain is often referred to as an immutable and distributed ledger.

In short, the difference is Decentralized Control

Decentralized control eliminates the risks of centralized control. Anybody with sufficient access to a centralized database can destroy or corrupt the data within it. Users are therefore reliant on the security infrastructure of the database administrator.

Blockchain technology uses decentralized data storage to sidestep this issue, thereby building security into its very structure.

Blockchain technology has the potential to disrupt and improve many industries and traditionally centralized systems. However, before it can become a real, viable alternative to its centralized counterparts, blockchains must be able to scale and process transactions at speeds way above its current capabilities. The number one limitation of blockchains is scalability. Put simply, it is hard for blockchains to grow and support increasing numbers of transactions. To visualize this, Visa and Mastercard can process thousands of transactions per second while Bitcoin can only process approximately 7 transactions per second. Solutions must be introduced to further enhance the capabilities of blockchains.

One way to address scalability is sharding, a process that breaks the data into manageable chunks distributed across different nodes. Blockchain sharding is already being used for private blockchain networks.

Database sharding allows application developers to be able to build more scalable and faster architectures. Sharding is an important solution, especially in the blockchain world, where data processing is still slow and only a small amount of data can be stored on-chain at the same time. Several blockchain & distributed ledger technology firms such as Shardus
are actively pursuing implementing sharding into distributed ledger technology and existing blockchain networks are also in the process of developing sharding as a scaling solution.