Berkeley DB (libdb) is a programmatic toolkit that provides embedded database support for both traditional and client/server applications. It includes b+tree, queue, extended linear hashing, fixed, and variable-length record access methods, transactions, locking, logging, shared memory caching, database recovery, and replication for highly available systems. DB supports C, C++, C#, Java, PHP, and Perl APIs. It supports key-value pair (NoSQL), SQL, and Java Object formatted data. It is available for a wide variety of Unix platforms as well as QNX, Android, Mac OS X, and several varieties of Windows.
hamsterdb Embedded Storage is an embedded database engine for C/C++, including wrappers for Java, .NET, and Erlang. It supports in-memory databases, very fast database cursors, "record number" databases, ACID transactions, and duplicate keys. hamsterdb is very fast and highly configurable. It compiles and runs on Unix platforms, Linux, Microsoft Windows, and embedded platforms.
MUSCLE (Multi User Server Client Linking Environment) is an N-way messaging server and networking API. It includes client-side networking APIs for various languages, including C, C++, C#, Delphi, Java, and Python. MUSCLE lets programs communicate over a network via streams of serialized Message objects. The included server program ("muscled") lets its clients message each other and store information in its server-side hierarchical database. The database supports flexible queries via hierarchical wildcarding, and "live" updates via a subscription mechanism.
SQLite is a small, fast, embeddable SQL database engine that supports most of SQL92, including transactions with atomic commit and rollback, subqueries, compound queries, triggers, and views. A complete database is stored in a single cross-platform disk file. The native C/C++ API is simple and easy to use. Bindings for other languages are also available.
ELOG Electronic Web Logbook is an electronic logbook with a Web interface. It can be used to maintain personal or shared logbooks, with the ability to add attachments to logbook pages. Logbook entries can be categorized with user-defined classes, and queried using filters on these classes. Automatic email notifications can be generated on new entries based on the classes. The ELOG server is a small stand-alone C program, which runs under Linux and Windows. No other packages are required. The logbooks are saved in plain ASCII files for easy and fast access.
OpenLink Virtuoso is a scalable, high-performance SQL-200n compliant object-relational database engine. It provide sophisticated database management for SQL, XML, and RDF. All interaction with Virtuoso occurs via its support of industry standard query languages, protocols, APIs, and data formats such as: ODBC, JDBC, OLE-DB, ADO.NET, XMLA, SQL, SPARQL, XQuery, SOAP, HTTP, WebDAV, SyncML, Atom (Publishing and Syndication), RSS, RDF, and more.
Redland is a set of C libraries providing a high-level API for the Resource Description Framework (RDF), allowing it to be stored, parsed, serialized, queried, and manipulated. It has an object-based, modular design and comes with detailed reference documentation and examples. Redland supports all RDF vocabularies such as FOAF, RSS 1.0, Dublin Core, DOAP, and OWL, the query languages SPARQL and RDQL, and all RDF syntaxes including Turtle, RDF/XML, RDF/JSON, RSS, Atom, RDFa, and GRDDL.
The unixODBC project provides Unix applications with the same ODBC 3.51 API and facilities available under Windows. It provides a Driver Manager that supports the full ODBC API and performs the ODBC 3 to ODBC 2 translations with UNICODE to ANSI conversion. It also includes a set of graphical utilities that allow users to specify connections to DBMSes to be used by applications, a collection of ODBC drivers including a simple text based driver, an NNTP driver, a Postgres driver and others, and a selection of templates and libraries that to aid in the construction of ODBC drivers. It works with MySQL, Postgres, StarOffice/OpenOffice, Applixware, iHTML, PHP, Perl DBD::ODBC, and many other applications and drivers. Connection pooling is also provided to increase performance with applications such as PHP.
CLIP is a Clipper/XBase compatible compiler with initial support other xBase dialects. It features support for international languages and character sets. It also features OOP, a multiplatform GUI based on GTK/GTKextra, all SIX/Comix features (including hypertext indexing), SQL and ODBC drivers, a C-API for third-party developers, a few wrappers for popular libraries (such as BZIP, GZIP, GD, Crypto, and Fcgi), a multitasking client and application server based on TCP/IP sockets, object data base utilities, and a functions library.
PostGIS adds support for geographic objects to the PostgreSQL object-relational database. In effect, PostGIS "spatially enables" the PostgreSQL server, allowing it to be used as a backend spatial database for geographic information systems (GIS), much like ESRI's SDE or Oracle's Spatial extension.