BuntDB vs NCache vs Redis: What are the differences?

## Introduction
BuntDB, NCache, and Redis are popular in-memory databases used for various applications. Each has its unique features and functionalities.

1. **Scalability**: BuntDB is limited in scalability as it does not support clustering or sharding, while NCache and Redis offer robust scalability through clustering and sharding capabilities. NCache and Redis can scale horizontally by distributing data across multiple nodes, providing better performance and availability for larger datasets.

2. **Persistence**: NCache and Redis both provide persistence options, allowing data to be stored on disk in addition to being held in memory. BuntDB, on the other hand, is an in-memory database and does not offer persistent storage capabilities, making it more suitable for temporary data storage or caching purposes.

3. **Data Structure Support**: Redis supports a wide range of data structures, including strings, lists, sets, hashes, and more, making it versatile for various use cases. NCache also supports multiple data structures but is primarily designed for caching. BuntDB, on the other hand, offers a simpler key-value store with limited data structure support compared to Redis and NCache.

4. **Querying Capabilities**: Redis and NCache provide advanced querying capabilities through features like Redis commands and SQL-like queries in NCache, allowing for efficient data retrieval and manipulation. BuntDB, being a key-value store, has limited querying capabilities and is more suited for simple read and write operations.

5. **Consistency and Durability**: NCache and Redis ensure consistency and durability through features like replication, failover mechanisms, and data persistence options, making them suitable for mission-critical applications. BuntDB, while efficient for in-memory operations, may lack the durability and consistency guarantees provided by NCache and Redis.

6. **Community Support**: Redis has a large and active community supporting its development, with extensive documentation, libraries, and resources available for users. NCache also has a dedicated user base and support services, while BuntDB may have limited community support and resources due to its niche use cases and simplicity.

## Summary
In summary, BuntDB is a simple in-memory database suitable for lightweight applications, while NCache and Redis offer more advanced features such as scalability, persistence, querying capabilities, consistency, and community support, making them ideal choices for high-performance and mission-critical applications.