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.
db4o is an object database for Java and all .NET environments. Its features include ACID transactions, automatic class schema recognition, query-by-example, a S.O.D.A. object querying API, native queries, LINQ support on .NET, callback methods, memory files, cascade-on-delete, multi-threaded access, and Java Webstart and servlet support.
Mimer SQL is an SQL-based, high-performance RDBMS, targeted at mission-critical client/server environments. It offers scalable performance (including multi-processor support), and is available in all major Unix (including Linux), Windows, and OpenVMS platforms. It offers Optimistic Concurrency Control as the transaction handling method, instead of the more commonly used locking-type.
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.
mysqldiff is a Perl script which compares the data structures (i.e. table definitions) of two MySQL databases and returns the differences as a sequence of MySQL commands suitable for piping into mysql which will transform the structure of the first database to be identical to that of the second (c.f. diff and patch). Database structures can be compared whether they are files containing table definitions or existing databases, local or remote.
The Easysoft ODBC-ODBC Bridge allows applications on one machine to access ODBC data sources on another. It supports multiple concurrent connections from multiple clients to multiple target databases. The principle application is to enable access from Linux and Unix platforms to remote ODBC databases. For example, Apache/PHP programs on Linux can read/write data held on MS SQL Server on Windows, and Perl programs can read/write data held in a MS Access database. Supported applications include Applixware, Open Office, Python, Rexx/SQL, mnGoSearch, OpenLDAP, and Oracle sqlplus. Supported platforms include Linux, MacOSX, IBM zSeries, Windows and various Unix flavors.
The OpenLink Universal Data Access Driver Suite is a suite of high-performance drivers for ODBC, JDBC, OLE DB, and ADO.NET that enable development of database-independent applications. It supports OpenLink Virtuoso, Oracle, Microsoft SQL Server, Microsoft ACCESS, IBM DB2, Informix, Sybase, Ingres II, Progress, PostgreSQL, DBASE, Paradox, and other ODBC-compliant databases. It runs on x86, Itanium, Opteron, PPC, and Sparc, etc. platforms.
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.