Agenda for Week 1/31 & 2/2. Learn about database design Vocabulary Modeling tool: Entity relationship diagram (ERD) Practical modeling concepts Do database design Practice creating ERD’s Primarily from “draftsman” perspective. Database Design.
Example of a logical ERD symbol
Example of a Physical ERD symbol
Possible Solution #1: Put the quantity ordered ( symbolqty_ordered) in the item entity, and create a concatenated primary key
Possible solution#1: Results in redundant data for item name, cost and sell price
Possible solution #2: Uses an intersection entity ( name, cost and sell priceOrderline) to avoid redundant data.