ruby-on-rails - Rails 教程:SQLite3::ConstraintException:唯一约束失败:users.email

Question

我正在关注 Rails 教程。我在 ch。 6，我在使用 SQLite3 时遇到一个奇怪的错误(为了记录，我使用的是 sqlite 版本 1.3.10，而教程使用的是 1.3.9)

我在运行 rake db:migrate 时没有收到错误消息，但是当我为测试环境运行迁移时，我得到了以下信息:

$ bundle exec rake test:models

rake aborted!
ActiveRecord::PendingMigrationError:

Migrations are pending. To resolve this issue, run:

    bin/rake db:migrate RAILS_ENV=test

sample_app/test/test_helper.rb:3:in `<top (required)>'
sample_app/test/models/user_test.rb:1:in `require'
sample_app/test/models/user_test.rb:1:in `<top (required)>'
Tasks: TOP => test:models
(See full trace by running task with --trace)


$ bundle exec rake db:migrate RAILS_ENV=test

== 20150628011937 AddIndexToUsersEmail: migrating ===========================
==
    -- add_index(:users, :email, {:unique=>true})
rake aborted!
StandardError: An error has occurred, this and all later migrations canceled:


SQLite3::ConstraintException: UNIQUE constraint failed: users.email: CREATE UNIQUE INDEX "index_users_on_email" ON "users" ("email")sample_app/db/migrate/20150628011937_add_index_to_users_email.rb:3:in `change'
C:in `migrate'
ActiveRecord::RecordNotUnique: SQLite3::ConstraintException: UNIQUE constrain
t failed: users.email: CREATE UNIQUE INDEX "index_users_on_email" ON "users"
("email")
sample_app/db/migrate/20150628011937_add_index_to_users_email.rb:3:in `change'
C:in `migrate'
SQLite3::ConstraintException: UNIQUE constraint failed: users.email
sample_app/db/migrate/20150628011937_add_index_to_users_email.rb:3:in `change'
C:in `migrate'
Tasks: TOP => db:migrate
(See full trace by running task with --trace)

这是我的 user.rb 模型:

class User < ActiveRecord::Base
  before_save { self.email = email.downcase }
  validates :name, presence: true, length: { maximum: 50 }
  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 }
end

这是我最近的迁移

  class AddIndexToUsersEmail < ActiveRecord::Migration
    def change
      add_index :users, :email, unique: true
    end
  end

如果相关，我可以发布任何其他文件。在此先感谢您的帮助!

Answer 1

问题是在迁移之前，我在数据库中有用户使用相同的电子邮件。
db:reset解决了一切