MemSQL vs VoltDB: What are the differences?

1. Scalability: MemSQL boasts of horizontal as well as vertical scalability, making it suitable for varying workloads and data volumes. On the other hand, VoltDB primarily focuses on horizontal scalability, thereby excelling in scenarios requiring high transaction throughput with low-latency requirements.

2. Consistency Model: MemSQL follows a typical distributed database model with its use of synchronous replication, allowing for strong consistency guarantees. In contrast, VoltDB utilizes a partition-based architecture along with its single-threaded execution model to provide serializable isolation levels, ensuring strong consistency in distributed environments.

3. Query Optimization: MemSQL incorporates a cost-based query optimizer that enhances query performance by generating optimal execution plans. Meanwhile, VoltDB leverages stored procedures to mitigate network overhead and latency, offering improved performance for transactional workloads.

4. Data Storage: MemSQL can support a hybrid architecture with a combination of in-memory and disk-based storage for efficient data processing. On the contrary, VoltDB is an in-memory database system, ensuring high-speed data access and processing capabilities without the need for disk storage, ideal for real-time data processing requirements.

5. Architecture: MemSQL follows a traditional shared-nothing architecture, enabling efficient distribution of data and processing across nodes in a cluster. In contrast, VoltDB employs an in-memory, lock-free, distributed architecture that ensures linear scalability and fault tolerance without sacrificing performance, making it suitable for high-demand transactional applications.

6. Use Cases: MemSQL is well-suited for analytical workloads, complex queries, and real-time dashboarding due to its hybrid storage capabilities and robust query optimization features. Conversely, VoltDB is ideal for use cases that require high-speed, high-throughput transaction processing, such as financial services, gaming, telecommunications, and real-time analytics applications.

In Summary, MemSQL and VoltDB differ in scalability options, consistency models, query optimization techniques, data storage approaches, architectural designs, and targeted use cases, catering to distinct data processing needs and workload requirements.