Speedy is a SQL-database with some unique features especially important for unit-testing. It is small, fast and simple to use. It contains a rich set of SQL-commands (e.g. sub-selects, joins, distinct).
(commercial) The SQLBase Embedded Database offers scalability from the Desktop to the Web. With its small footprint yet robust functionality, SQLBase provides developers a way to create, deploy and support applications requiring an embedded database, whether being used on the desktop, on a web server, or in a distributed/mobile application.
(commercial) SQLflex is a powerful, full featured SQL that delivers all the capabilities of both Informix-ESQL/C and Informix standard engine, but as low as 10% of the cost. If you are already using Informix, you will be able to replace Informix without modifying your existing code or databases.
Sqsh (pronounced skwish) is short for SQshelL (pronounced s-q-shell), it is intended as a replacement for the venerable 'isql' program supplied by Sybase.
Tdbengine is a "relational database management system" - in short: RDBMS - with an integrated programming language. It represents the enhancement of the famous DOS-TDB and is predestined to handle databases on the web. It connects to the webserver using the standard cgi interface. The tdbengine is very small (about 400 KByte), extremely quick and easy to administrate. Currently versions for Linux (x86), FreeBSD (x86) and Windows NT/2000 are available.
(commercial) TEXIS is a fully integrated SQL RDBMS that intelligently queries and manages databases containing natural language text, standard data types, geographic information, images, video, audio, and other payload data.
ThinkSQL is a powerful, cross-platform relational database management system designed for modern operating systems and hardware. It aims to comply fully with the ISO SQL standard to provide an open and flexible SQL server for your applications. ThinkSQL uses a multi-versioning engine to provide consistent views of data and concurrent access to rows without locking. The server also has stored procedures and functions (using the standard syntax), and has support for large multimedia objects.
TurnKey MySQL appliance
TurnKey MySQL appliance is an easy-to-use, lightweight, installable live CD of the MySQL database. It can run on real hardware in addition to most types of virtual machines. It features a Mac OS X-themed Web management interface and a Python configuration and installation console. It is based on Ubuntu 8.04.1 Hardy LTS, and is designed to provide users with a pre-integrated, automatically updated, turn-key operating system environment that is carefully built from the ground up with the minimum components needed to run the MySQL database with maximum usability, efficiency, and security.
A database management system. It has a data definition language (DDL) which lets the programmer define tables and relations. A special tool converts the DDL specification into a database description file which then tells the database how to build the tables and access the data.