Validate unique field in Rails app - ruby-on-rails

Question

In my Rails app, I've got two models - User and Account.
A User can have many Accounts.
An Account includes a name field as shown in the schema below.
How can I validate that the name field is unique for an Account but not necessarily unique in the database? For example, User1 could have an Account with the name Cash and User2 could have a different Account but with the same name Cash.
user.rb:
class User < ActiveRecord::Base
has_many :accounts
before_save { self.email = email.downcase }
VALID_EMAIL_REGEX = /\A[\w+\-.]+#[a-z\d\-.]+\.[a-z]+\z/i
validates :email, presence: true,
length: { maximum: 255 },
format: { with: VALID_EMAIL_REGEX },
uniqueness: { case_sensitive: false }
has_secure_password
validates :password, presence: true, length: { minimum: 6 }
# Returns the hash digest of the given string.
def User.digest(string)
cost = ActiveModel::SecurePassword.min_cost ? BCrypt::Engine::MIN_COST :
BCrypt::Engine.cost
BCrypt::Password.create(string, cost: cost)
end
end
account.rb:
class Account < ActiveRecord::Base
belongs_to :user
has_many :balances
before_save { self.active = true }
validates :name, presence: true, length: { maximum: 250 },
uniqueness: { case_sensitive: false }
validates :user, presence: true
end
schema.rb:
....
create_table "accounts", force: :cascade do |t|
t.string "name"
t.boolean "credit"
t.boolean "active", default: true, null: false
t.datetime "created_at", null: false
t.datetime "updated_at", null: false
t.integer "user_id"
end
create_table "balances", force: :cascade do |t|
t.decimal "balance"
t.date "date"
t.integer "account_id"
t.datetime "created_at", null: false
t.datetime "updated_at", null: false
end
create_table "users", force: :cascade do |t|
t.string "email"
t.boolean "admin"
t.datetime "created_at", null: false
t.datetime "updated_at", null: false
t.string "password_digest"
end
add_index "users", ["email"], name: "index_users_on_email", unique: true
....

Answer 1

You can use scope:
in your account.rb
validates :name, uniqueness: { scope: :user_id}
four you actual validates:
validates :name, presence: true, length: { maximum: 250 },
uniqueness: { case_sensitive: false, scope: :use_id }
active record validates