searching through joined polymorphic association with table_name defined - ruby

Question

i have two models
class Profession < ApplicationRecord
has_many :users
end
class User < ApplicationRecord
self.table_name = 'accounts'
belongs_to :scope, polymorphic: true
end
and a query:
Profession.joins(:users).where(accounts: {scope: some_scope_variable })
when I run that i get
Mysql2::Error: Unknown column 'accounts.scope' in 'where clause'
what i also tried is
Profession.joins(:users).where(users: {scope: some_scope_variable })
but it also doesnt work and gives similar error
Mysql2::Error: Unknown column 'users.scope' in 'where clause'

Answer 1

According to the documentation, polymorphic associations rely on two columns being present on the model. Example
class User < ApplicationRecord
belongs_to :thingable, polymorphic: true
end
These columns should exist on users:
thingable_id
thingable_type
If you want to query them through an association, you may use the columns directly, like:
Profession.joins(:user).where(users: { thingable_id: 42, thingable_type: 'Foo' })
Also, I'd reconsider the name scope, since this is used by Rails already.
EDIT:
After submitting the answer above, I started understanding your question, sorry about this.
I reproduced it and made it work like this:
class Profession < ApplicationRecord
has_many :users, as: :thingable # <-- this is missing in your case
end
class User < ApplicationRecord
self.table_name = 'accounts'
belongs_to :profession
belongs_to :thingable, polymorphic: true
end
Now we can do this:
Profession.joins(:users).where(accounts: { age: (20..30) })
The WHERE-clause on the joined table is translated to SQL without any magic and checks:
WHERE `accounts`.`age` BETWEEN 20 AND 30
Whereas, the WHERE-clause on self-columns are sometimes magically modified:
User.where(thingable: 42)
results in
WHERE `accounts`.`thingable_id` = 42
-- ^^^ added by Rails
So, if we want to filter on any of these polymorphic columns, we do
Profession.joins(:users).where(accounts: { thingable_id: 111 })