8

私はこのスキーマを持っています：Postbelongs_toCategoryとCategoryhas_manyPost。投稿とカテゴリはgemglobalize3でグローバル化されます

class Post < ActiveRecord::Base
  belongs_to :category
  translates :title, :excerpt, :desc # globalize3
end

class Category < ActiveRecord::Base
  has_many :posts
  translates :name # globalize3
end

PostsControllerで、次のコード行を含むすべての投稿を取得します。

def index
  @posts = Post.includes([:translations, {:category => :translations}])
end

問題は、カテゴリ変換テーブルでn+1クエリの問題があることです。

Post Load (0.3ms)  SELECT "posts".* FROM "posts"

Post::Translation Load (0.3ms)  SELECT "post_translations".* FROM "post_translations" WHERE ("post_translations".post_id IN (2,3,4))

# START n+1 query block
Category Load (1.9ms)  SELECT "categories".* FROM "categories" WHERE ("categories"."id" IN (9,12,11))
Category::Translation Load (0.4ms)  SELECT "category_translations".* FROM "category_translations" WHERE ("category_translations".category_id = 9) AND ("category_translations"."locale" IN ('it'))
CACHE (0.0ms)  SELECT "category_translations".* FROM "category_translations" WHERE ("category_translations".category_id = 9) AND ("category_translations"."locale" IN ('it'))
Category::Translation Load (0.2ms)  SELECT "category_translations".* FROM "category_translations" WHERE ("category_translations".category_id = 12) AND ("category_translations"."locale" IN ('it'))
CACHE (0.0ms)  SELECT "category_translations".* FROM "category_translations" WHERE ("category_translations".category_id = 12) AND ("category_translations"."locale" IN ('it'))
Category::Translation Load (0.2ms)  SELECT "category_translations".* FROM "category_translations" WHERE ("category_translations".category_id = 11) AND ("category_translations"."locale" IN ('it'))
CACHE (0.0ms)  SELECT "category_translations".* FROM "category_translations" WHERE ("category_translations".category_id = 11) AND ("category_translations"."locale" IN ('it'))
# END n+1 query block

Category::Translation Load (0.5ms)  SELECT "category_translations".* FROM "category_translations" WHERE ("category_translations".category_id IN (9,12,11))

このn+1クエリの問題を解決するにはどうすればよいですか？

4

2 に答える 2

12

モデルで翻訳の一括読み込みを有効にする必要があります。これを行うための推奨される方法は次のとおりです。

class Category < ActiveRecord::Base
  has_many :posts
  translates :name # globalize3

  default_scope includes(:translations)
end
于 2013-10-02T09:19:09.900 に答える