Question

我有以下应用。电影有很多评论，电影观众有很多评论。当我尝试将评论与电影相关联时，我收到以下错误

Review Load (0.1ms)  SELECT "reviews".* FROM "reviews" WHERE "reviews"."movie_id" = 5
SQLite3::SQLException: no such column: reviews.movie_id: SELECT "reviews".* FROM     "reviews"  WHERE "reviews"."movie_id" = 5
ActiveRecord::StatementInvalid: SQLite3::SQLException: no such column: reviews.movie_id:     SELECT "reviews".* FROM "reviews"  WHERE "reviews"."movie_id" = 5

使用sql gui编辑器后，我发现正确的查询应该是

SELECT "reviews".* FROM "reviews" WHERE "movie_id" = 5

review.rb

class Review < ActiveRecord::Base
  belongs_to :movie
  belongs_to :moviegoer
  attr_protected :moviegoer_id
end

movie.rb和moviegoer.rb有

has_many：评论

在他们中间。 schema.rb

ActiveRecord::Schema.define(:version => 20130222225620) do

create_table "moviegoers", :force => true do |t|
t.string   "name"
t.string   "provider"
t.string   "uid"
t.datetime "created_at", :null => false
t.datetime "updated_at", :null => false
end

create_table "movies", :force => true do |t|
t.string   "title"
t.string   "rating"
t.text     "description"
t.datetime "release_date"
t.datetime "created_at",   :null => false
t.datetime "updated_at",   :null => false
end

create_table "reviews", :force => true do |t|
t.integer "potatoes"
t.text    "comments"
t.integer "moviegoers_id"
t.integer "movies_id"
end

end

我做错了什么？为什么rails会查询“评论”。“movie_id”而不仅仅是“movie_id”？

Answer 1

迁移中的列名错误。 rails常规是外键是单数的。如果它们不是那么你需要通过关联的选项哈希告诉rails外键是什么。

要么回滚迁移，修复列名称（moviegoers_id也是错误的），然后再次迁移，或者告诉rails外键。

Class Review < ActiveRecord::Base
  belongs_to :movie, :foreign_key => 'movies_id'
  belongs_to :moviegoer, :foreign_key => 'moviegoers_id'
end

同样必须发生在两个模型的许多方面。

rails没有这样的列错误

1 个答案: