alefever39 / phase-3-practice-code-challenge-aliens-among-us

Practice Code Challenge - Aliens Among Us

Learning Goals

• Write Active Record Migrations
• Connect between tables using Active Record Associations
• Write class and instance methods using Active Record
• Use Active Record to query the database

Introduction

Aliens are among us! And they're here in order to visit their human friends on the planet Earth. Build out the rest of this super secret app for the MIB so they can track different visitations by aliens and their human friends.

Getting started

run bundle install

Migrations

Create your migrations.

• Aliens should have a name, a earth_disguise_name, a home_planet, and a light_years_to_home_planet

• Earthlingsshould have a first_name, a last_name and a job

• Visitations should have a date, an alien_id and an earthling_id

aliens Table

Column	Type
name	string
earth_disguise_name	string
home_planet	string
light_years_to_home_planet	integer

earthlings Table

Column	Type
first_name	string
last_name	string
job	string

visitations Table

Column	Type
date	string OR datetime
alien_id	integer
earthling_id	integer

Relationship

• What associations will this need?
• (i.e. has_many, has_many through, and belongs_to)

Earthling

• Earthling#visitations returns all the visitations for an earthling
• Earthling#aliens returns every alien that has visited that earthling
• Earthling#full_name returns the combination of the human's first name and last name
• Earthling.filter_by_job(job) takes in a job as a string and returns all earthlings with the specified job

Alien

• Alien#visitations returns all the visitations that alien has been involved in
• Alien#earthlings returns every earthling the alien has visited
• Alien#visit(earthling) takes in an instance of an earthling and creates a visitation linking that earthling and alien for today's date
• Alien#total_light_years_traveled returns the light years from the alien's home planet multiplied by the number of visitations for that alien ... times two (because they have to travel both ways right?)
• Alien.most_frequent_visitor returns the alien with the most visitations
• Alien.average_light_years_to_home_planet returns the average distance for all aliens to their home planets

Visitation

• Visitation#alien returns the alien involved in the visitation
• Visitation#earthling returns the earthling involved in the visitation