jPersist is an extremely powerful object-relational database persistence API that manages to avoid the need for configuration and annotation; mapping is automatic (A-O/RM). It uses JDBC, and can work with any relational database and any type of connection resource. It uses information obtained from the database to handle mapping between the database and Java objects, so mapping configuration is not needed, and annotation is not needed. In fact, there is no configuration needed at all.
The Skeleton Engine is a starting point for creating a MySQL Storage Engine. It comes with everything you need to write a pluggable engine. Autoconf, an initial framework, and scripting tools are all provided. The Skeleton Engine has been the starting point for the PBXT, Nitro, Memcache, AWS, HTTP, and many other engines.
libmysqltemplate is a very high speed C state machine template library that uses MySQL data for the source of the templates and optionally for name/value pairs. It is required for the mysqlApache2/mysqlMail2/iDNS family of openisp.net/unixservice.com Web based consoles for clusters and other complex Internet service infrastructure management.
Tokyo Cabinet is a library of routines for managing a database. It is the successor of QDBM. Tokyo Cabinet runs very fast. For example, the time required to store 1 million records is 1.5 seconds for a hash database and 2.2 seconds for a B+ tree database. Moreover, the database size is very small. For example, the overhead for a record is 16 bytes for a hash database, and 5 bytes for a B+ tree database. Furthermore, the scalability of Tokyo Cabinet is great. The database size can be up to 8EB.
Cybercluster is a multi-master replication solution. Cybercluster has no single point of failure, an integrated load balancer, an integrated replication server, a monitoring server (to track replication), a consistency checker, an optional 2 Phase Commit for cluster-wide writing, support for all PostgreSQL features. Cybercluster is easy to setup. In contrast to many other solutions, Cybercluster is built on top of the PostgreSQL core and has full access to PostgreSQL internals. Cybercluster is heavily based on the concepts of PGCluster.