After today's class (and online readings and videos) you should:
Lecture Notes: You have lecture notes posted on this topic. They are here for convenience. Please read chapter 12 of the book.
Videos:
ER_Diagram
ternary_ER_Diagram
Full_ER_Diagram
Another_ER_Diagram
Ternary_ER_Diagram_Another_Example
A nice tool to draw ER Diagrams is draw.io which is very good and free.
Assignments: ER Model Assignment
Good luck!