CouchDB is a document-centered database system that provides fast and flexible access to structured schema-less data. Built in the Erlang Language, CouchDB is intended to not only be easy to use, but also have the capability to accommodate many different usage profiles with great ease. These guides will help you install and configure CouchDB on your VPS.
MariaDB is a community-developed, open-source, drop-in replacement for MySQL.
MongoDB is an open source database management system written in C++. Like other systems such as CouchDB, MongoDB seeks to resolve issues that relational database management systems have through document-based management.
MySQL is a popular open source database system, powering thousands of web and server applications. Available in all major Linux distributions, this package provides a high performance storage engine for a wide variety of databases.
Oracle 10g Express Edition provides a great database platform for development purposes, relational database study, or small to mid-size production environments. Based on Oracle's immensely popular enterprise-grade database, this product is free for use and redistribution. These guides will help you get up and running with Oracle 10g XE on your Linux VPS.
PostgreSQL is an open source relational database management system. Known for high performance and standards compliance, this database system serves as the foundation for many popular open source software applications. These guides will help you install and configure PostgreSQL on your VPS.
Redis is an open source data store solution designed for deployments in high performance environments and for applications where performance and flexibility are more critical than data persistence and absolute data integrity. Designed as a key-value store or a "data structures storage system", Redis may be considered a participant in the "NoSQL" movement like MongoDB and CouchDB. These documents provide both instructions for deploying the Redis server and overviews of best practices for maintaining Redis instances.