What Is a Blockchain Database? Learn the Basics

Blockchain is famous as the technology that facilitates peer-to-peer transactions of cryptocurrencies like Bitcoin. But at its core, this technology is really just a ledger that stores transaction information in a decentralized manner. Based on this, blockchains can be considered a type of database with several other use cases from simply storing operational data to solutions made using custom blockchain development capabilities.

All the benefits and features of blockchain technology result from how this database is structured. In this post, we will examine the concept of a blockchain database to help you learn how it works, its benefits, and potential limitations. 

• A blockchain database is a decentralized digital ledger where data is stored in blocks across multiple nodes. 
• The structure of the blockchain’s distributed database ensures security, data integrity, transparency, and efficiency. 
• Key components of a blockchain database include blocks (containing transaction data), chains (cryptographic links between blocks), nodes (participating computers), and consensus mechanisms for data validation.
• Despite the benefits of blockchain databases, this technology is difficult to scale, has high implementation costs, and is affected by regulatory uncertainties.

What Is a Blockchain Database?

A blockchain database is a type of database system built on blockchain technology. In a blockchain database, data storage is on a decentralized digital ledger managed by a network of computers instead of a centralized repository. Several participating computers (nodes) on the blockchain network store a consistent and tamper-proof record of the same data. This ensures secure and immutable data storage.

How Blockchain Databases Work?

A blockchain database is a distributed digital ledger where events or transaction data are structured into cryptographically linked blocks. Data in a blockchain database is stored as signed blocks. Each block contains a list of transaction data or events being recorded. 

Depending on what the database is being used for, the block of data could be a cryptocurrency transaction, smart contract executions, supply chain records, digital files, IoT data, and so on. The timestamp for when the block was created and a unique signature (cryptographic hash) of the previous blocks are also included in each block. 

Once a block is full, it is linked to the previous blocks in a sequence. The sequence of blocks is stored in a decentralized manner. Unlike traditional databases where all the data are stored in a single location, a blockchain ledger is distributed across a network of computers. A consensus mechanism is used to ensure that all the nodes store an identical copy of the ledger and they all agree on the state of the blockchain at any given time.  

Note that a blockchain implementation does not always have to save data directly. In some cases, the data itself is stored off-chain in relational databases, while the blockchain database layers are used to store a reference or hash of the data. This is particularly useful for storing larger datasets while maintaining the security and transparency benefits of blockchain.

Types of Blockchain Databases

The data structures and administration of a blockchain network can give rise to different types of blockchain databases. These blockchains differ in how they’re managed, and the nature of participating nodes. This also has an impact on their potential use cases. Here’s an overview of the different blockchain types and how they work.

Public Blockchain 

A public blockchain-bassed database is built on an open and permission-less blockchain network. This means anyone can join the network, access the data stored in the ledger, and participate in the consensus process. Examples include databases built on open-source blockchain platforms like Bitcoin and Ethereum.

Private Blockchain

Private blockchains are open only to a specific group of participants. Only these authorized entities can add data to the database, access the network, and participate in blockchain governance. Hyperledger Fabric and R3 Corda are good examples of blockchains on which a private database can be built. 

Hybrid Blockchain  

A hybrid blockchain is one that combines elements of both public and private blockchain networks. This type of database structure is useful for organizations that want to share some information with the public while also keeping sensitive data private. Examples of public blockchain networks include Dragonchain and Cardano.

Consortium 

Consortium blockchains offer more centralized control compared to other types of blockchains. However, instead of a single central authority, this blockchain is controlled by a group of organizations. Quorum and Hyperledger Sawtooth are great examples of a consortium blockchain. 

Key Components of Blockchain Databases

The basic structure of a blockchain-based database solution consists of a chain of blocks stored on a distributed ledger across multiple nodes or computers. Before new blocks are created and added to the chain, all the nodes must agree to the validity of the data. This is known as the consensus mechanism. Here’s an overview of the main components of a blockchain database:

• Blocks: They are the fundamental building blocks of a blockchain database. It is a collection of transactions that have been bundled together and added to the blockchain. In addition to a list of all the transactions and event data, a blockchain also includes a time stamp and a hash value. 
• Chain: When a new blockchain block has been created, it is added to previously created blocks by a chain. This forms a continuous sequence of blocks linked in chronological order. The link between blocks is secured with a cryptographic hash function. This is an algorithm that converts data into a fixed string of characters known as the hash value. Since each block stores the hash value of the block before it, the blockchain data is practically immutable. 
• Consensus Mechanism: Before new data is added to the blockchain, participating nodes on the network must agree to its validity. This is achieved through a consensus mechanism, which is a protocol that determines how the nodes achieve agreement. Blockchains use various algorithms, including Proof-of-Work and Proof-of-Stake protocols to ensure that all participating nodes have a consistent view of the ledger. 
• Nodes: The term “node” refers to the individual computers that participate in a blockchain network. Each node stores a full copy of the entire blockchain ledger. They also participate in validating, accepting, and rejecting the formation of new blocks on the blockchain. Since blockchain data is stored on nodes, there’s no need for a central authority to validate and control transactions. 

Blockchain Database Design

For blockchain database deployment, you need to consider the key components of the blockchain network such as the data structure, cryptographic hashing, and the validation rules for the consensus mechanism. 

The first step in blockchain-based database design is to define how the data in the blocks will be structured. A typical block will store a list of transactions with their timestamps, the previous hash, and a nonce (for a Proof-of-Work blockchain). Next, you need to implement cryptographic hashing, which is the algorithm that computes the hash value of each block before it is added to the chain. 

Then you need to implement validation rules that will confirm the validity of every transaction before they’re added to the ledger. The validation rule will also verify the hash value of a new block before it is added to the chain. 

Finally, you should choose a consensus mechanism for the blockchain. The consensus mechanism will determine how the network participants validate blocks or blockchain transactions. 

How Is Blockchain Different from Traditional Database Models?

Like a conventional database, blockchain can be used to store all kinds of information or data types including binary files, transactional data, text files, and media files. However, blockchains differ from traditional database systems in the way they store and manage data. Some of these blockchain characteristics and key differences are highlighted below.

Structure

The basic difference between blockchain and traditional databases is in how they store or organize data. In a conventional database, the data has a simple structure with the data points grouped into rows and columns. Blockchain stores a list of transactions or event data in blocks containing hashes and other unique identifying information. The blocks are then cryptographically linked to form a chain. Note that not all forms of distributed ledger systems store information on a chain. Some DLTs like hashgraph use an interconnected web of data. Read our article on hashgraph vs blockchain to learn more.  

Decentralization 

A traditional database has a centralized structure. This means the data is stored in one central location under the control of a single entity that determines how new data is added to the database, modified, or removed. The defining quality of a blockchain-based database is decentralized control. For this type of data, multiple participating nodes across the network store an identical copy of the data. All nodes can access the data and participate in validating new data before they’re added to the blockchain database. 

Administration

As mentioned above, a central authority is in charge of managing a traditional blockchain system. They can add new data to the database directly, modify, edit and even determine who has access and the scope of this access. A blockchain system does not have a central administrator. Instead, it has multiple administrators in the form of decentralized nodes.

Although any of the decentralized nodes can add data to the blockchain, the new data has to be validated by the participating nodes. When a node wants to create a new record, details of the record are first broadcast to all the other nodes. These nodes then vet the new record based on the consensus mechanism of the blockchain ecosystem. The new data is only added after it has been successfully verified this way. 

Immutability

Another key difference between these database systems is that blockchain data is immutable, meaning data are extremely difficult to change. Every new block that is created has a digital signature known as the hash which points to the exact record stored in the block. A new block will also store the hash value of the block before it. To alter the data in a block, one would have to recalculate the block’s hash and update the hash for all subsequent blocks connected to it on the chain. Since this is practically impossible, blockchain data can only be read or added to the blockchain, but not modified, ensuring data integrity.

Performance

Regular databases outweigh blockchain databases in terms of their performance. That’s because blockchain systems have an extra layer of verification that makes it difficult to update or retrieve data from the database. Any new transaction must be validated by all the decentralized nodes before the blockchain is updated. This is a potentially lengthy process depending on the blockchain structure, network traffic, and consensus mechanism.  

How To Create a Blockchain Database?

The process of creating a blockchain database involves selecting the right type of blockchain and setting up the necessary infrastructure. Here’s a summary of the key steps involved in creating a blockchain powered by blockchain protocols. 

• Define the purpose of the database: The first step is to determine the specific use case for your database. The use case will determine the kind of data that will be stored, the level of security, and how users will interact with the database. 
• Pick a blockchain platform: There are several blockchain ecosystems that can serve as the foundation for your blockchain database. Examples include Ethereum, Corda, Hyperledger, and so on. Each of these blockchain projects has its own unique data structure and features that make them useful for specific use cases. 
• Develop the smart contract: The smart contract is a self-executing program that determines how the blockchain solution will run and the process for querying data or performing other database operations. Once you have selected a protocol, the next step is to define the rules and logic for the database using programming languages like Solidity or Java. 
• Deploy the database: The final step is to deploy the database and smart contract you have designed to the platform you have selected. You also need to test the database and carry out regular maintenance to ensure optimal performance and security.

Benefits of Blockchain Database

Building modern databases on a blockchain protocol allows you to leverage the benefits offered by the technology over traditional alternatives. Some of the benefits of adopting a blockchain database include: 

• Enhanced security: In blockchain, data blocks are linked cryptographically. Hashing algorithms convert the blockchain data into unique strings that are stored on subsequent blocks. This makes it harder for hackers to steal or tamper with the data. The fact that the blockchain ledger is stored on multiple nodes also means there’s no single point of failure like there is in traditional databases. 
• Transparency: Blockchain systems (especially public blockchains) are transparent by design. This means users that are connected to the network can access data if they want. Consequently, this type of database is useful for systems where participants need to track data to prevent fraud such as supply chain management.
• Decentralization: Unlike traditional databases, a blockchain platform developed to store data is not controlled by a single entity or organization. This makes it more resilient to corruption, tampering, and censorship.

Challenges and Limitations

Despite the numerous benefits of adopting a blockchain architecture for database development, there are a few limitations to consider in any deployment scenario. Some of these challenges are highlighted below: 

• Scalability issues: Blockchain transactions need to be validated by the blockchain’s consensus mechanism before they’re added to the database. This verification process can be slow and energy-consuming. This creates efficiency and performance issues especially when the database has large data volumes. 
• Regulatory concerns: Blockchain is still grossly misunderstood. As a result, there are still significant legal uncertainties about the deployment scenario of this technology across various jurisdictions. Existing laws and regulations may not be favorable to database systems built on blockchain. 
• Technological costs: Implementing blockchain solutions can be quite costly due to the software and hardware infrastructure costs. Traditional databases have been able to resolve the high cost of database management through the “as-a-service”. This model which can help cut costs significantly isn’t quite popular in the blockchain world yet. 

Blockchain Database Examples and Use Cases

• Finance: Blockchain in banking has been one of the most promising use cases of the technology. A blockchain-based database can be used to store customer information securely in financial organizations. More than just storing data, this technology can also be used for operational reporting and may also facilitate cross-border payments with great efficiency. 
• Supply chain: A blockchain-based database can be used to track the movement of goods in a supply chain. Using this technology instead of a traditional database will ensure transparency and authenticity.
• Healthcare: Blockchain can be used to streamline patient data management in healthcare. The adoption of blockchain-based electronic health records (EHRs) will simplify the process of sharing data with healthcare providers, health insurance companies, and other stakeholders while still ensuring data security. 
• Digital identity management: A blockchain database can be used to manage the digital identities of users. Blockchain offers a higher level of security and trustability, which is perfect for sensitive use cases like this.
• Real estate: In the real estate industry, blockchain can be used to store information relating to property titles and other information that validates the ownership of an asset. These tokenized assets can be transferred seamlessly, with the blockchain preserving the trail or ownership and simplifying authentication. 

Top Blockchain-based Databases

The numerous potential applications of a blockchain-based database have given rise to a good number of database projects built on this technology. Some top examples of blockchain-based databases include: 

• BigchainDB: BigchainDB is a blockchain-based database that allows the deployment of large-scale applications on the blockchain. It offers benefits like immutability, decentralization, and native asset creation. BigChainDB was originally created as a traditional database before blockchain features were added. 
• Cassandra: Also called Apache Cassandra, this distributed database is an open-source system based on the NoSQL database. It is used by thousands of enterprises to store blockchain transactional data, smart contract data, and block information. The Cassandra query language is highly scalable and can handle large amounts of data. 
• ChainifyDB: ChainifyDB is a blockchain database that can be used to transform enterprise database infrastructures into blockchain systems. While ChainfyDB does not have its own database, it plugs a blockchain layer into any existing database provided to it. Plugged databases of this nature offer the best of both worlds since you now have two database layers.

Create Blockchain Database with CrustLab

Blockchain technology provides a secure way to store data for various use cases. It also has the potential to improve your blockchain analytics and data processing, so you can make better decisions. If you’re looking to leverage blockchain technology and all its benefits for various database instances, then you should contact CrustLab. As your reliable custom blockchain software development company, we help you make the most of blockchain databases to give your business a competitive edge. Contact us now to learn more and get started.