KeyDB

vs

Apache HBase

MongoDB is an open-source document-oriented distributed database built for modern applications. MongoDB uses JSON-like documents with optional schemas and is classified as a NoSQL database. The database is freely distributed under the Server Side Public License, but MongoDB provides commercial version of the database for enterprise-scale applications.

Redis is a free and open-source, in in-memory data structure store that can be used as a database, cache or message broker. The project is community developed and released under the BSD license. Redis supports common data structures including strings, hashes, lists, sets, sorted sets with range queries, bitmaps, hyperloglogs, geospatial indexes with radius queries and streams.

CouchDB is a free and open-source document-oriented NoSQL database developed by the Apache Foundation. The database is written and implemented in the language Erlang and provides the use of multiple formats and protocols to store, transfer, and process data. With CouchDB you query data with JavaScript using MapReduce, and HTTP for an API. Which can be done across multiple distributed CouchDB instances as the database has the ability to synchronize multiple copies of the same database, across servers.

SQLite is a free and open-source relational database management system that implements a small, fast, self-contained, high-reliability, full-featured, SQL database engine. Rather than being a typical client–server database engine, SQLite is self-contained and can be embedded into applications. Making it perfect for development frameworks that want to provide a default database without setup, or applications that needs an embedded database. SQLite is built into all mobile operating systems and most computers and comes bundled with a countless applications. SQLite is also ACID-compliant and implements most of the SQL standard, generally following PostgreSQL syntax.

PostgreSQL, or Postgres for short is a widely popular, free and open-source relational database management system. PostgreSQL is available for all major operating systems including macOS, Linux, Windows, BSD and Solaris. The project has been in active development for over 30 years now, and powers many of the applications you use on a daily basis.

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.