Question

当我尝试将friendly_id设置为我的rails4项目similarly时，我在“朋友”之后将“朋友”添加到friends表后出错。我该如何解决呢？

    PG::UniqueViolation - ERROR:  duplicate key value violates unique constraint "index_friends_on_slug"
    DETAIL:  Key (slug)=() already exists.

此外，以下是我的文件，问题可能基于：

# app/models/friend.rb:
class Friend < ActiveRecord::Base
    has_many :entries, dependent: :destroy
    belongs_to :user

    extend FriendlyId
    friendly_id :candidates, use: [:slugged, :finders] # not :history here

    def candidates
    [
      :first_name,
      [:first_name, :last_name]
    ]
    end
end


    # db/schema.rb:
    create_table "friends", force: true do |t|
        t.string   "first_name"
        t.string   "last_name"
        t.text     "address"
        t.string   "email"
        t.string   "phone"
        t.string   "slug"
        t.integer  "user_id"
        t.datetime "created_at"
        t.datetime "updated_at"
    end

    add_index "friends", ["slug"], name: "index_friends_on_slug", unique: true, using: :btree
    add_index "friends", ["user_id"], name: "index_friends_on_user_id", using: :btree

更新：迁移文件：

class CreateFriends < ActiveRecord::Migration
  def change
    create_table :friends do |t|
      t.string :first_name
      t.string :last_name
      t.text :address
      t.string :email
      t.string :phone
      t.string :slug
      t.integer :user_id

      t.timestamps
    end

    add_index :friends, :slug, unique: true
    add_index :friends, :user_id
  end
end

Answer 1

现在通过在config/initializers/friendly_id.rb上取消注释这些行来修复：

  # Most applications will use the :slugged module everywhere. If you wish
  # to do so, uncomment the following line.
  #
  config.use :slugged, :finders
  #
  # By default, FriendlyId's :slugged addon expects the slug column to be named
  # 'slug', but you can change it if you wish.
  #
  config.slug_column = 'slug'

感谢@basgys，@ DavidGrayson和我们其他人......

Answer 2

该错误使得它听起来像数据库中的两行共享相同的slug，这只是空字符串，并且这是不允许的，因为您在slug列上添加了唯一索引。

错误何时实际发生？什么击键或点击会导致它？

删除friends表中的行或通过从迁移文件中删除该选项使索引非唯一（您可以稍后通过其他迁移更改它）。

“key（slug）=（）已经存在”在rails4应用程序的friendly_id中

2 个答案: