Theory of DBMS LINKS: http://www.databasedev.co.uk/primary_foreign_keys.html *** http://www.jkinfoline.com/extended-er-features.html *** Theory of OS Not really much use now since I came across this after the exam. Made a mistake in my paper too... 10 marks down the drain. Anyway: ^ The examples above really clarifies any doubts there is. |