Blockchain Technology is a leading one of the most secure technology which is used to facilitate transactions and track assets in business networks. An asset can be in the form of tangible (car, house) or intangible (intellectual property, patents). These things can be virtually tracked and traded through blockchain Technology, eventually reducing the risk of any obstacles. Thus, making it the most secure network through which one can track his transaction.
The data is stored in the blockchain as signed blocks that are linked together forming a chain of blocks. Any transaction first needs to be validated by the majority of nodes in the network and once it is validated the transaction will be added to the block and the block will be broadcasted to all the nodes in the network.
What is Blockchain Database?
Blockchains are like databases that are functionally and structurally different. While databases store data using ‘table’ data on the other hand blockchains store data in blocks. Blockchain databases are decentralized while the traditional relational database is centralized.
- A blockchain is distributed decentralized ledger that stores information in blocks.
- Every blockchain may be considered a database but every database cannot be considered a blockchain.
- Blockchain databases are considerably slow in performance in comparison to traditional databases.
Blockchain vs Database
Below are some of the differences between blockchain and database:
| Parameters |
Blockchain |
Database |
|---|---|---|
| Control over data | Blockchain has decentralized control over the data. | The traditional database has centralized control over data. |
| Administrator | Blockchain does not require an administrator as the exact same copy of data is maintained at each node in the network. | In the database, the data is maintained by an administrator. |
| History | In Blockchain, there is real-time information but it allows one to track the history of transactions. | Traditional databases record present information only. Thus, it is not possible to trace the history of transactions. |
| Performance | Blockchains have slow performance when considered for digital transaction technology. | Relational databases outperform blockchains in terms of performance. |
| Data Integrity | Blockchains make it impossible for an attacker to tamper with data in the network without breaking the chain. | If necessary measures are not taken then it may be possible for an attacker to alter the data in databases. |
| Operations on transactions | In the blockchain, it is only possible to read or add data to the blockchain database | The database allows read, write, update, and delete operations on the data. |
| Permission | Blockchains are permissionless as anyone can access them. | Databases are permissioned as they can be accessed only by the individuals who have the right to access them. |
| Confidentiality | Blockchain is secure and confidential. | Databases are not fully confidential. |
| Recursive | Blockchains are not recursive as one cannot go back to repeat a task on any record. | Databases are recursive as one can go back to repeat a task on a particular record. |
Different Ways to Create Blockchain Database
There are 2 factors to consider before creating a blockchain database:
- Database deployment in enterprise or consortium: It is important to determine whether the database will be used in the enterprise or consortium. In some cases, it may be possible that an enterprise is using blockchain internally for data storage and acts as a central authority governing the data. In this case, the blockchain database is centralized. But in the majority of the cases, blockchains operate in a consortium where there is no single source that owns and control data. Cryptocurrencies are one such example.
- Data usage: Second most important factor to consider is how data will be used. Operational data is the data used directly by the clients connecting to the database. For example, cryptocurrencies are where there is no intermediary. Non-operational data is the one that can be accessed via an intermediary.
Considering the above 2 factors there are 4 possible ways to create a blockchain database:
- Centralized With Operational Data/ Operational Blockchain Data Store With Enterprise.
- Centralized With Non-operational Data/ Non-operational Blockchain Data Store With Enterprise.
- Decentralized With Operational Data/ Operational Blockchain Data Store With Consortium.
- Decentralized With Non-operational Data/ Non-operation Data Store With Consortium.
Let’s discuss each of these in detail.
1. Centralized With Operational Data/ Operational Blockchain Data Store With Enterprise: When a blockchain is deployed inside an enterprise it does not need to be decentralized. Centralization simplifies the deployment and at the same time, it offers the advantages of the blockchain also compared to other databases.
- This data store is useful in decision-making and operational reporting.
- The database needs to be controlled by two or more administrators, each of whom will be operating from different locations.
- This database provides the immutability to the documents and at the same time possibility to create and transfer assets.
- This deployment provides a third-party auditor with a solid track for asset transfer.
- The administrators would be responsible for reviewing the transactions whenever necessary.
- In this data store, clients directly access the data without any intermediary as part of the data is stored on the blockchain.
- It does prevent outside clients to access the data.
2. Centralized With Non-operational Data/ Non-operational Blockchain Data Store With Enterprise: In this case, also the blockchain database deployment is centralized and is maintained by a limited number of administrators. This approach is different in the sense that here intermediaries are set up who can access the data store and send it to clients.
- In this type of blockchain database, the data is not accessed directly by the clients.
- Here, clients connect to the database instances that in return connect and offload the parts of the data on the blockchain.
- This approach offers better performance as less number of nodes are required to accept a transaction.
- Since data is only accessible to a limited number of clients so this method adds more privacy to the blockchain database.
3. Decentralized With Operational Data/ Operational Blockchain Data Store With Consortium: In this deployment scenario, a consortium is created to remove the need for a single entity to control the database. The consortium can be made up of multiple databases.
- This approach ensures that the database is decentralized.
- All companies act as individual nodes and thus are responsible for maintaining the database.
- Decentralization increases the immutability of the data.
- For example, Supply chain management, etc.
4. Decentralized With Non-operational Data/ Non-operation Data Store With Consortium: In this deployment scenario, multiple administrators from different consortium members control the blockchain.
- Intermediaries are here to help clients to access data in the database.
- This approach provides increased speed and privacy as there is a limited number of clients accessing the blockchain.
- For example, companies that hold personal information and sales details that might be required by the outsider parties and affiliate organizations who are not allowed to access the database directly.
Blockchain Database Design
There are two main issues that are faced if one thinks of using Blockchain as a Database:
- The blockchain contains transactional data but has very limited querying capabilities.
- To validate a block in the blockchain, a majority of the nodes need to approve it. The more there are nodes in the network the more time it takes to validate a block.
Instead of using blockchain as a database, it is advisable to take an existing database and then add blockchain features on top of it. Here, two database layers are used:
- The first layer uses a lightweight consensus protocol that can provide data integrity with good performance for querying.
- The second layer uses the PoW consensus mechanism to store evidence of database operations for the first layer. The two layers are connected through the blockchain anchoring mechanism where the anchoring mechanism links the first layer with the blocks of the second layer. Thus, creating a chain of evidence validating the data from the first layer.
Challenges in Building Blockchain Database
- Querying capabilities: The blockchain as a database can store transactions and data but it lacks querying capabilities which is the key disadvantage.
- Scalability: Public blockchain lacks scalability as adding decentralized nodes in the blockchain network results in more network traffic and thus reduces the blockchain transaction throughput.
- Low throughput: Decentralized node in the blockchain network results in more network traffic but since more nodes are required to approve a transaction so it results in reduced blockchain transaction throughput.
- High latency: Popular blockchain networks like bitcoin and Ethereum has high latency.
Top 5 Blockchain-based Database
Below are the top 5 blockchain-based databases:
1. BigchainDB: Ithet is a blockchain-bassed database provided by MongoDB that enables one to add decentralized and blockchain qualities to the application. It also permits the deposition of large-scale applications in numerous use cases.
- The records stored in BigChainDB are immutable and tamper-proof.
- The database is decentralized which means there is no single point of failure.
- Various types of assets can be stored in BigChainDB.
- The use of the Tendermint consensus protocol makes it possible for BigChainDB to attain high performance.
2. Cassandra: It is an open-source NoSQL distributed database that delivers linear scalability. Cassandra is trusted by thousands of companies for high availability without compromising performance. It is a unique blockchain-based database for project purposes due to the presence of notable features.
- Cassandra is a distributed database.
- It is also fault-tolerant due to its distributed nature as there is no single point of failure.
- Cassandra uses Cassandra Query Language (CQL) for querying data from the database.
3. ChainifyDB: It is a blockchain solution for databases. It provides a layer in which databases can be plugged into the ChainifyDB network. Chainify DB also synchronizes the databases.
- The communication in ChainifyDb is encrypted between the plugged databases.
- This database can be seamlessly plugged into any data store or database without affecting the applications running on the databases.
4. Modex BCDB: It is a middleware software product that provides a plug-and-play approach for organizations. Modex BCDB is drawn to the plan of offering a real-time experience of data protection.
- It is a combination of traditional database and blockchain Technology.
- Modex BCDB supports multiple databases.
- It provides security while simultaneously managing the data.
5. Postchain: It is a blockchain platform developed by Chromeby in Sweden. It has a network of nodes that maintain a set of data through a proof-of-authority consensus algorithm.
- It is a modular-based framework database used for implementing custom blockchains.
- It stores data in an SQL database.
- In Postchain database the transactions are not written to the database via SQL code.