PostgreSQL is a robust relational database system with over 25 years of active development that runs on all major operating systems. It is fully ACID compliant, and has full support for foreign keys, joins, views, triggers, and stored procedures (in multiple languages). It includes most SQL92 and SQL99 data types, including INTEGER, NUMERIC, BOOLEAN, CHAR, VARCHAR, DATE, INTERVAL, and TIMESTAMP. It also supports storage of binary large objects, including pictures, sounds, or video. It has native programming interfaces for C/C++, Java, .Net, Perl, Python, Ruby, Tcl, and ODBC, among others, and exceptional documentation.
SymmetricDS provides file and database synchronization with support for multi-master replication, filtered synchronization, and transformation across the network in a heterogeneous environment. It supports multiple subscribers with one-direction or bi-directional, asynchronous data replication. It uses Web and database technologies to replicate data as a scheduled or near-realtime operation. The software has been designed to scale for a large number of nodes, work across low-bandwidth connections, and withstand periods of network outage. It works with most operating systems, file systems, and databases, including Oracle, MySQL, MariaDB, PostgreSQL, MS SQL Server (including Azure), IBM DB2, H2, HSQLDB, Derby, Firebird, Interbase, Informix, Greenplum, SQLite (including Android), Sybase ASE, and Sybase ASA (SQL Anywhere) databases.
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.
CloverETL is Java-based tool/framework for data integration and creation of data transformations. It is component based and follows the concept of transformation graphs which consist of individual nodes/components performing simple (or complex) operations on data. Any transformation can be defined as a set of interconnected nodes through which data flows. CloverETL can be used as a standalone application or be embedded into a larger project.
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.
H2 is an SQL database engine written in Java that implements the JDBC API. Embedded, server, and clustering modes are available. A browser based console application is included. The database has strong security features. Disk based and in-memory databases and tables are supported.
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.
phpPgAdmin is a fully functional PHP-based administration package for PostgreSQL. It has all the basic functionality you need to completely administer a PosgreSQL server and/or database, including the ability to administer views, sequences, stored procedures, and triggers. Features include the ability to create and drop databases; create, copy, drop, and alter tables/views/sequences/functions/triggers; edit and add fields (to the extent Postgres allows); execute any SQL-statement, even batch-queries; manage keys on fields; create and read dumps of database and tables; and administer one single database, multiple servers, and Postgres users/groups.