join two tables to get data rails 4 - ruby-on-rails

Question

class Guardian < ActiveRecord::Base
has_many :patients
has_one :user, as: :profile
accepts_nested_attributes_for :user
end
class User < ActiveRecord::Base
belongs_to :profile, :polymorphic => true
devise :database_authenticatable, :registerable,
:recoverable, :rememberable, :trackable, :validatable
end
User migration
class DeviseCreateUsers < ActiveRecord::Migration
def change
create_table(:users) do |t|
## Database authenticatable
t.string :email, :null => false, :default => ""
t.string :encrypted_password, :null => false, :default => ""
t.string :username, :null => false
t.string :address
t.integer :age
t.string :gender
t.string :name
t.integer :profile_id
t.string :profile_type
## Recoverable
t.string :reset_password_token
t.datetime :reset_password_sent_at
## Rememberable
t.datetime :remember_created_at
## Trackable
t.integer :sign_in_count, :default => 0, :null => false
t.datetime :current_sign_in_at
t.datetime :last_sign_in_at
t.string :current_sign_in_ip
t.string :last_sign_in_ip
t.timestamps
end
add_index :users, :email, :unique => true
add_index :users, :reset_password_token, :unique => true
end
end
class DeviseCreateUsers < ActiveRecord::Migration
def change
create_table(:users) do |t|
## Database authenticatable
t.string :email, :null => false, :default => ""
t.string :encrypted_password, :null => false, :default => ""
t.string :username, :null => false
t.string :address
t.integer :age
t.string :gender
t.string :name
t.integer :profile_id
t.string :profile_type
## Recoverable
t.string :reset_password_token
t.datetime :reset_password_sent_at
## Rememberable
t.datetime :remember_created_at
## Trackable
t.integer :sign_in_count, :default => 0, :null => false
t.datetime :current_sign_in_at
t.datetime :last_sign_in_at
t.string :current_sign_in_ip
t.string :last_sign_in_ip
t.timestamps
end
add_index :users, :email, :unique => true
add_index :users, :reset_password_token, :unique => true
end
end
Guardian migration
class CreateGuardians < ActiveRecord::Migration
def change
create_table :guardians do |t|
t.string :family_name
t.timestamps
end
end
end
I want to get data from user table and guardian table in a single variable
guardian has one user and user belongs_to guardian as profile(polymorphic). i want to get data from user table and from guardian table where guardian_id=users.profile_id

Answer 1

Try
Guardian.select("*").joins(:user)
Edit:
if you have columns with the same name from the join you can do
Guardian.select("guardians.family_name, guardians.id as g_id, users.id as u_id,
users.name, users.email, users.username, users.address, users.age,
users.gender").joins(:user).where(:users => {:u_id => #user_session.id})

Answer 2

For some reason above answer didn't work for me, so I tried direct sql query
sqlQuery = "select tableA.column1, tableB.column2 from tableA inner join tableB on tableA.some_id = tableB.id"
ActiveRecord::Base.connection.execute(sqlQuery)