BigchainDB

vs

TerminusDB

PouchDB is a free and open-source JavaScript database inspired by Apache CouchDB. The database is designed from the ground-up to run well within modern web browsers. With PouchDB you can create web applications that works as well offline as they do online. PouchDB achives this by storing data locally, then synchronize it with CouchDB and compatible servers when the user get internet access once again. This is especially useful for applications facing countries and regions with lower quality internet connections or unstable infrastructure.

OrbitDB is free and open-source serverless, distributed, peer-to-peer database for IPFS (Internet Planetary File System). The database is most commonly used for decentralized apps (dApps) and blockchain applications. With OrbitDB, IPFS is used for data storage, while IPFS Pubsub is used to automatically sync databases with peers across the network. Which makes OrbitDB an "eventually consistent database" that uses CRDTs for conflict-free database merges, suited for decentralization of data.

RxDB is short for Reactive Database and is a NoSQL-database for JavaScript Applications like Websites, hybrid Apps, Electron-Apps, Progressive Web Apps and NodeJs. Reactive means that you can not only query the current state, but subscribe to all state changes like the result of a query or even a single field of a document. This is great for UI-based realtime applications in way that makes it easy to develop and also has great performance benefits. To replicate data between your clients and server, RxDB provides modules for realtime replication with any CouchDB compliant endpoint and also with custom GraphQL endpoints.

RedisGraph is the first free and open source queryable Property Graph database to use sparse matrices to represent the adjacency matrix in graphs and linear algebra to query the graph.

Neo4j is a commercially provided graph database management system developed by Neo4j, Inc. The graph database is fundamentally different to the relational model found in relational database management systems (RDBMS). With Neo4j, each data record, or node, stores direct pointers to all the nodes it's connected to. The database is also designed to perform complex queries with complex connections orders of magnitude faster. Neo4j is ACID-compliant and suited for projects that requires complicated relationship structures.

JanusGraph is a free and open-source distributed, scalable graph database optimized for storing and querying graphs containing hundreds of billions of vertices and edges distributed across a multi-machine cluster. The project is managed by The Linux Foundation and is released under the Apache Software License 2.0. Large corporations like Expero, Google, GRAKN.AI, Hortonworks, IBM and Amazon also supports the project.