Megan Rolfes

A scenario where a join could be used is if you like a specific author and are looking to read a new book by them. You would have book in one table with a primary key of Book_ID and info like the genre, length, etc. Author would be in another table with a primary key of Author_ID and containing info like first name and last name. You can join…[Read more]

Personally, I find the most difficult aspect of ERDs to be cardinality. After narrowing down which nouns in the problem statement are relevant, assigning attributes to these entities and determining the relationships is fairly simple. Cardinality is especially tricky though because you have to understand the maximum and minimum number of times…[Read more]