Question

这是一个Rails 3.0.9应用程序。

以下是place模型及其与city和address的belongs_to关联，两者都有has_many :places关联。 place模型使用虚拟属性，视图实现jQuery auto_completion。它在Railscasts第102集中实现。在演员表中，它显示单个category模型。但在我的实施中，place模型有2个模型city和address

我已经使用虚拟属性来完成自动完成，如果记录不存在，则必须创建它。

class Place < ActiveRecord::Base
  belongs_to :city
  belongs_to :address

  def city_name
    city.name if city
  end

  def city_name=(name)
    self.city = City.find_or_create_by_name(name) unless name.blank?
  end

  def address_name
    address.name if address
  end

  def address_name=(name)
    self.address = Address.find_or_create_by_name(name) unless name.blank?
  end
end

这是city模型。 address模型与类名Address也相同。

class City < ActiveRecord::Base
  has_many :events
  has_many :places
  validates :name, :presence => true,
            :length => {:maximum => 30, :message => "Address can't be longer than 30 chars."}, 
            :uniqueness => {:message => "has already been taken", :case_sensitive => false}

end

当我尝试使用city_name和address_name创建一个已存储在数据库中的值时，它可以正常工作。
当我尝试使用不存在的/新city_name和address_name添加时，它可以正常工作。
当任何或两个现有记录和我试图放入不同的情况时，例如地址Thamel已存在，但我提出thamel（已降低案例），它会出现以下错误报告：

这是日志中的回溯：

Processing by PlacesController#create as HTML
  Parameters: {"utf8"=>"✓", "authenticity_token"=>"5igpohqctBnRUWjPYu6GnXo6btx8SDe/PJRgF2eTG2A=", "place"=>{"name"=>"aaaa", "image_cache"=>"", "category_id"=>"1", "sub_category_id"=>"2", "hot"=>"0", "featured_till_date"=>"", "opens"=>"11 am", "street"=>"", "address_name"=>"thamel", "city_name"=>"pokhara", "description"=>"sdfdsf"}, "commit"=>"Post my Place"}
  Address Load (0.3ms)  SELECT "addresses".* FROM "addresses" WHERE "addresses"."name" = 'thamel' LIMIT 1
  SQL (0.3ms)  SELECT 1 FROM "addresses" WHERE (LOWER("addresses"."name") = LOWER('thamel')) LIMIT 1
  City Load (0.2ms)  SELECT "cities".* FROM "cities" WHERE "cities"."name" = 'pokhara' LIMIT 1
  SQL (0.3ms)  SELECT 1 FROM "cities" WHERE (LOWER("cities"."name") = LOWER('pokhara')) LIMIT 1
  User Load (0.9ms)  SELECT "users".* FROM "users" WHERE "users"."id" = 11 ORDER BY created_at DESC LIMIT 1
  CACHE (0.0ms)  SELECT "addresses".* FROM "addresses" WHERE "addresses"."name" = 'thamel' LIMIT 1
  CACHE (0.0ms)  SELECT 1 FROM "addresses" WHERE (LOWER("addresses"."name") = LOWER('thamel')) LIMIT 1
  CACHE (0.0ms)  SELECT "cities".* FROM "cities" WHERE "cities"."name" = 'pokhara' LIMIT 1
  CACHE (0.0ms)  SELECT 1 FROM "cities" WHERE (LOWER("cities"."name") = LOWER('pokhara')) LIMIT 1
  SQL (0.3ms)  SELECT 1 FROM "places" WHERE (LOWER("places"."name") = LOWER('aaaa')) LIMIT 1
  CACHE (0.0ms)  SELECT 1 FROM "cities" WHERE (LOWER("cities"."name") = LOWER('pokhara')) LIMIT 1
  CACHE (0.0ms)  SELECT 1 FROM "addresses" WHERE (LOWER("addresses"."name") = LOWER('thamel')) LIMIT 1
  AREL (0.5ms)  INSERT INTO "places" ("user_id", "name", "image", "category_id", "sub_category_id", "opens", "street", "city_id", "address_id", "description", "created_at", "updated_at") VALUES (11, 'Aaaa', NULL, 1, 2, '11 am', '', NULL, NULL, 'sdfdsf', '2011-07-31 15:00:25.182849', '2011-07-31 15:00:25.182849')
SQLite3::ConstraintException: places.city_id may not be NULL: INSERT INTO "places" ("user_id", "name", "image", "category_id", "sub_category_id", "opens", "street", "city_id", "address_id", "description", "created_at", "updated_at") VALUES (11, 'Aaaa', NULL, 1, 2, '11 am', '', NULL, NULL, 'sdfdsf', '2011-07-31 15:00:25.182849', '2011-07-31 15:00:25.182849')
Completed 500 Internal Server Error in 28625ms

ActiveRecord::StatementInvalid (SQLite3::ConstraintException: places.city_id may not be NULL: INSERT INTO "places" ("user_id", "name", "image", "category_id", "sub_category_id", "opens", "street", "city_id", "address_id", "description", "created_at", "updated_at") VALUES (11, 'Aaaa', NULL, 1, 2, '11 am', '', NULL, NULL, 'sdfdsf', '2011-07-31 15:00:25.182849', '2011-07-31 15:00:25.182849')):
  app/controllers/places_controller.rb:39:in `create'

太奇怪了。当我尝试创建一个city_name和address_name不存在的地方时，不知道为什么它的行为不符合预期？

Answer 1

试试这样：

class Place < ActiveRecord::Base
  belongs_to :city
  belongs_to :address

  def city_name
    city.name if city
  end

  def city_name=(name)
    self.city_id = City.find_or_create_by_name(name).id unless name.blank?
  end

  def address_name
    address.name if address
  end

  def address_name=(name)
    self.address_id = Address.find_or_create_by_name(name).id unless name.blank?
  end
end

Answer 2

实际上问题出在sqlite3 db上。我将db和适配器更改为mysql2，现在相同的代码可以正常工作。

如果给出不同的套接字输入，则自动完成关联的Rails会打击

2 个答案: