Big picture references
- UML at Wikipeida – look at all the pictures
- Yes, it was in CSCI 202
- UML Profile for Database Design
- Is the Entity-relationship (ER) model dated?
- some UML tools
Terminology
For the most part, I’m just following the Tom Jewett’s Database design with UML and SQL. Consider this to be a list of buzz words.
- classes entities
- names
- attributes
- associations relations
- keys – identify a row
- primary key
- foreign key
- multiplicities candinalities – α.β or just α
- 1.1 – one to one
- 1.* – one to many
- The multiplicities next to one end of a link represent the “fanout” of the class at the other end
- multiplicities influence the number of tables needed in the database
- For one-to-one, foreign keys can be used for the reference
- For many-to-many, junction tables may be necessary
- association class may be tied to a relation
- subclasses
- complete or incomplete
- disjoint or overlapping
- aggregation
- with an clear diamond, denotes a 0.1 relation
- with an filled diamond, denotes a 1.1 relation also called composition
- recursion – relations can point to their own class