database - find attribute in a rails model with another has_many relationship -

i don't know how bring question, going explain it.

i have next models: movie, genre , theater. movies , theaters have many-to-many relationship. movies , genres have same relationship.

in rails:

• theaters has_many movies
• movies belongs_to theaters
• movies has_many genres
• genres belongs_to movies

my problem:

with theater = theater.all.first (for example) can first theater , theater.movies , movies theater has. how can movies specific genre? must nice way it, din't find any.

first of describe "in rails", not many-to-many relation, one-to-many. has_and_belongs_to_many or has_many :through relations. see activerecord associations

what want, should easy. if have genre available, a_genre.movies work. otherwise you'll need start movie , construct query:

movie.joins(:genres).where({genres: { name: ['comedy', 'drama']}}) movie.joins(:genres, :theaters).where({genres: { name: ['comedy', 'drama']}}).   where({theaters: { city: 'ny' }})