For Databases and Information Systems Semester 1, our practical sessions use Erwin (for documenting ERDs) and Oracle (or an alternative database if you wish).
These are available in the lab (bar last week's sign in problems) but you may want to have your own independant set up to use outside of college.
You can download a free copy of Erwin (Erwin Community Edition) at
http://erwin.com/products/detail/ca_erwin_data_modeler_community_edition/
and a free copy of Oracle Express at:
http://www.oracle.com/technetwork/database/express-edition/overview/index.html.
Susan