I'm trying to figure out the different modeling constructs for ER models. I understand Chen Notation fine, I just need help figuring out crow's foot and IDEF1X.
On crow's foot, I understand that the 'trident' or the circle mean many. What do the vertical lines mean? When is it approriate to have the dot, or the line. On a sheet that my prof gave me, both are there for '1 to many' relationships.
With IDEF1X, there is a black dot denoting many. What would a 'P' mean by the dot? What does the small white diamond mean?
On crow's foot, I understand that the 'trident' or the circle mean many. What do the vertical lines mean? When is it approriate to have the dot, or the line. On a sheet that my prof gave me, both are there for '1 to many' relationships.
With IDEF1X, there is a black dot denoting many. What would a 'P' mean by the dot? What does the small white diamond mean?
