CouchDB is described as 'Apache CouchDB is a distributed, fault-tolerant and schema-free document-oriented database accessible via a RESTful HTTP / JSON API. It includes incremental map / reduce mechanics for queries and keeps data safe with an append-only datastore' and is a relational database in the development category. There are more than 50 alternatives to CouchDB for a variety of platforms, including Linux, Windows, Mac, Self-Hosted and Web-based apps. The best CouchDB alternative is PostgreSQL, which is both free and Open Source. Other great apps like CouchDB are MySQL Community Edition, MongoDB, MariaDB and Redis.
Filesystem-backed document DBMS in Rust where every record is a Git-versionable JSON file with automatic cryptographic integrity for compliance-critical systems.
CUBRID is a comprehensive GPL/BSD open source relational database management system highly optimized for Web Applications. CUBRID is being developed in C/C++. Includes native HA, online hot backup, and other features. JDBC, PHP, ODBC/.NET, Ruby & Python APIs.
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