Amazon DynamoDB

vs

Apache Cassandra

Azure Cosmos DB is a non-relational NoSQL database trusted by leading enterprises globally. With Azure Cosmos DB you can run No-ETL analytics over real-time operational data and run near-real time analytics and AI on the operational data within your NoSQL database, to reduce time to insight.

The worlds most popular free open-source relational database, MySQL is used by 150,000 + companies across the globe. The relational database management system is released and distributed under the GPL license and openly developed by the community. MySQL uses SQL as its query language and is fully integrated and ACID compliant.

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.

Cockroach is a distributed key/value datastore that allow you to build, scale and manage modern, data-intensive applications. The database delivers distributed SQL by combining the familiarity of relational data with limitless, elastic cloud scale and bulletproof resilience. Correct data is a must for mission-critical and even the most common applications. CockroachDB provides guaranteed ACID compliant transactions, allowing you to fully trust your data.

ArangoDB is a database system that was designed to support key/value, document, and graph data to be stored together, and queried via a unified language called AQL. The project is developed by ArangoDB GmbH, and released free and open-source under the Apache License 2.0. The universal "native multi-level" design of the database allows for a flexible approach when structuring and building an application, a feature that many have come to love.

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.