5 links
Connection Strings List
connectionstrings.com
Contains connectionstrings for all types of datasources, databases and files, via ODBC, OLEDB, DataShapes.
Database Directory
databasedir.com
Provides short descriptions of the several popular RDBMS. Features various database articles.
Database Journal
databasejournal.com
Daily database news and articles for the database professional.
MS Access, Excel Database Design Tutorials
katsueydesignworks.com
Well written and thorough explanations on creating and maintaining database through MS Access and Excel.
Recognized Standards for Databases
-ccs.cs.umass.edu
Listed standards for database architectures including SQL, OLE, COM,CORBA. Links to DB Special Interest Groups and organizations too.