MSDN SQL Server
MSDN SQL Server
http://msdn.microsoft.com/sql/default.aspx
MS SQL Server
Visit this portal for all the latest news and articles to help you evaluate microsoft sql server 2005 for your data management and analysis needs.
http://www.microsoft.com/sql/
MySQL
MySQL
http://www.mysql.org/
Oracle
The world's largest enterprise software company, oracle is the only vendor to offer solutions for every tier of your business -- database, middleware, business intelligence, business applications, and collaboration. with oracle, you get information that helps you measure results, improve business processes, and communicate a single truth to your constituents.
http://www.oracle.com/index.html
SQLite
SQLite
http://www.sqlite.org/
PostgreSQL
PostgreSQL
http://www.postgresql.org/
Sybase
Sybase is the industry leader in business intelligence (bi) software including expert systems for database management, data warehousing and data mining, data integration and application development, as well as mobile solutions. whatever data requirements your business has, sybase can provide you with the applications, servers and tools you need to overcome the challenges that your enterprise has with data management.
http://www.sybase.com/