I need to make an ERD diagram that follows these rules. Would just 3 tables work? It doesn't seem like it to me because there are many to many relationships involved. Link to diagram at bottom of page.
For states we need to store data on state name, state code (for example CA for California) and capitol name.
For counties we need to store data on county name, county area (in sq miles), and which state the county is in.
For cities we need to store data on city name, population, and location (county and state).
Some notes:
-State codes are unique.
-Names of counties are only unique within a state.
-Names of cities are only unique within a county.
-A city is always located in a single county.
-A county is always located in a single state.
-A state will have one and only one capitol (which is a city).
