Rasqal is a C library for querying RDF graphs, supporting the SPARQL, RDQL, and LAQRS languages. It provides APIs for creating a query and parsing query syntax. It features pluggable triple-stores and matching interfaces, query engines for executing the queries, an API for manipulating results as bindings, and multiple ways to format the results to XML, CSV, TSV, and JSON. It uses the Raptor RDF parser to return triples from RDF content, and can alternatively work with the Redland RDF library's persistent triple stores. It is portable across many POSIX systems.
Sequoia provides high availability and performance scalability for databases. It is is the continuation of the C-JDBC project. It provides transparent database clustering (partitioning, replication, etc.). It works with any Java application without code modification and with any database engine. It has been successfully tested with Tomcat, JBoss, JOnAS, WebSphere, MySQL, PostgreSQL, Apache Derby, HSQLDB, SAP DB, Oracle, DB2, Sybase, MS SQL Server, Firebird, and more.
hk_classes is a set of C++ libraries for rapid development of database applications with all features a modern database application should have, like forms and reports. hk_classes is database and GUI independent. It also includes command line tools to use hk_classes in scripts. hk_classes includes drivers for DBase, Firebird, MS Access, MySQL, Paradox, PostgreSQL, ODBC, and SQLite.
Itzam is an embedded database engine that creates and manipulates files containing keyed-access records. Information is referenced by a user-defined key value, and one or more indexes (hash, B-tree, or matrix) may be combined with or separated from data. Itzam is deliberately portable and designed as a foundation for other languages (C++, Python, and Java).
QOF (Query Object Framework), provides a set of C Language utilities for performing generic structured complex queries on a set of data held by a set of C/C++ objects. This framework is unique in that it does not require SQL or any database at all to perform the query. Thus, it allows programmers to add query support to their applications without having to hook into an SQL database.
ROOT is an OO framework for large-scale scientific data analysis and data mining. It contains an efficient hierarchical OO database, a C++ interpreter, advanced statistical analysis, visualization, introspection, documentation, networking, and GUI classes. The command/scripting language is C++, and large scripts can be compiled and dynamically linked in. Using the PROOF (Parallel ROOT Facility) extension, large databases can be analyzed in parallel. The system runs on all known POSIX platforms, Windows, and MacOS X.
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.
JPOX provides transparent persistence of Java objects. It fully complies with the JDO1.0/JDO2.0/JDO2.1/JPA1 specifications. It supports persistence to all of the major RDBMSs on the market today, as well as DB4O. It allows querying using JDOQL, SQL, or JPQL. It comes with its own byte-code enhancer. Its 1.1 release is Sun's "Reference Implementation" (RI) for JDO2.0, and its 1.2 release is the RI for JDO2.1. It is highly extensible, using OSGi technology and providing a wide range of value-adding plugins.