Panick Mode!!!

Ah, what should I do about database!!!

I know abit more about integrity, man so hard to explain if there is an integrity broken in a SQL Database. Anyone got any examples, of how a certain integrity is broken in a SQL Database? I searched all over the internet, and nothing about it, except on wikipedia (woot woot! Go wiki!).

ER-Diagrams - anyone got an example of an ER-digram which is drawn from a case study? I tried doing it, but failed badly D: Anyone got any tips on how to draw it D: Tell me!!!

Total failure, help!