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.
Cego implements a relational and transactional database system with support for the SQL query language. The current release contains the most common database features for basic table manipulation and data retrieval. Indexes, foreign keys, views, and stored procedures are also implemented. Future releases (2.0 and above) will support a multi-node database concept with log file shipping for an automatic database application failover.
hamsterdb Embedded Storage is an embedded database engine written in ANSI-C. It includes B+Trees with variable length keys and records. It supports in-memory databases and endian-independent files, database cursors, multiple databases in one file, "record number" databases, and duplicate keys. hamsterdb is very fast and highly configurable. It compiles and runs on Unix platforms, Linux, Microsoft Windows, and Windows CE.
BaseX is a light-weight, high-performance, and scalable XML database system and XPath/XQuery processor, including full support for the W3C Update and Full Text extensions. An interactive and user-friendly GUI frontend gives you great insight into large XML data instances. It is platform independent and works out of the box.
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.
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.
nexB OpenAssets is a tool for inventorying, managing, and monitoring applications, software, hardware, networks, and generally any IT asset. It is designed so that system administrators, IT, and finance can determine what they have, how it is configured, what it is used for, and how much it is being used, so that informed decisions can be made. It complements existing network management software, integrates with a growing number of protocols and tools, and features no-agent discovery and inventory, configuration management including dependencies and correlation, monitoring, and reporting. It makes extensive and innovative use of XML, Xpath, and Xquery.
miniDB is a small and fast isam/btree library/program for record based access, used as standalone or as client/server. It features a small footprint, multi-field indexes, autoincrement fields, and database logging. All data is kept in a pure ASCII file, so you can also use grep and awk on it.