Rails Many to Many Associations

1. has_many through

   • requires a join model
   • name your join table anything
     • ex: memberships

   Pros:

   • more flexible, can add additional attributes(solumns) to join table
     Cons:
   • additional join model required

2. has_and_belongs_to_many

   • no join model necesary
   • assumes join table based on convention
     • ex: groups_users

   Pors:

   • easier, no join model

   Cons:

   • not as flexible, can’t add additional attributes(solumns) to join table