11

データベースの複数のフィールドに一意のインデックスがあります。したがって、重複するレコードに対してsaveを呼び出そうとすると、ActiveRecord :: StatementInvalidが発生し、mysqlエラーが表示されます。一意の制約を作成するか、これが発生したときに関連するエラーメッセージを返すようにすることで、レール内でこれを処理する方法はありますか？

ここにトレースがあります：

ActiveRecord::StatementInvalid: Mysql::Error: Duplicate entry '2010-12-09-2-0-1-1' for key 2: INSERT INTO `entries` (`rejected_at`, `created_at`, `comments`, `overtime`, `submitted_at`, `updated_at`, `time`, `approved`, `day`, `user_id`, `approved_at`, `job_id`, `submitted`, `rejected`) VALUES(NULL, '2010-12-09 21:50:46', NULL, 0, NULL, '2010-12-09 21:50:46', 2.0, NULL, '2010-12-09', 1, NULL, 1, NULL, NULL)
 from /home/cmatthews/src/cannon/vendor/rails/activerecord/lib/active_record/connection_adapters/abstract_adapter.rb:219:in `log'
 from /home/cmatthews/src/cannon/vendor/rails/activerecord/lib/active_record/connection_adapters/mysql_adapter.rb:319:in `execute'
 from /home/cmatthews/src/cannon/vendor/rails/activerecord/lib/active_record/connection_adapters/abstract/database_statements.rb:259:in `insert_sql'
 from /home/cmatthews/src/cannon/vendor/rails/activerecord/lib/active_record/connection_adapters/mysql_adapter.rb:329:in `insert_sql'
 from /home/cmatthews/src/cannon/vendor/rails/activerecord/lib/active_record/connection_adapters/abstract/database_statements.rb:44:in `insert_without_query_dirty'
 from /home/cmatthews/src/cannon/vendor/rails/activerecord/lib/active_record/connection_adapters/abstract/query_cache.rb:18:in `insert'
 from /home/cmatthews/src/cannon/vendor/rails/activerecord/lib/active_record/base.rb:2901:in `create_without_timestamps'
 from /home/cmatthews/src/cannon/vendor/rails/activerecord/lib/active_record/timestamp.rb:53:in `create_without_callbacks'
 from /home/cmatthews/src/cannon/vendor/rails/activerecord/lib/active_record/callbacks.rb:266:in `create'
 from /home/cmatthews/src/cannon/vendor/rails/activerecord/lib/active_record/base.rb:2867:in `create_or_update_without_callbacks'
 from /home/cmatthews/src/cannon/vendor/rails/activerecord/lib/active_record/callbacks.rb:250:in `create_or_update'
 from /home/cmatthews/src/cannon/vendor/rails/activerecord/lib/active_record/base.rb:2538:in `save_without_validation'
 from /home/cmatthews/src/cannon/vendor/rails/activerecord/lib/active_record/validations.rb:1078:in `save_without_dirty'
 from /home/cmatthews/src/cannon/vendor/rails/activerecord/lib/active_record/dirty.rb:79:in `save_without_transactions'
 from /home/cmatthews/src/cannon/vendor/rails/activerecord/lib/active_record/transactions.rb:229:in `send'
 from /home/cmatthews/src/cannon/vendor/rails/activerecord/lib/active_record/transactions.rb:229:in `with_transaction_returning_status'
 from /home/cmatthews/src/cannon/vendor/rails/activerecord/lib/active_record/connection_adapters/abstract/database_statements.rb:136:in `transaction'
 from /home/cmatthews/src/cannon/vendor/rails/activerecord/lib/active_record/transactions.rb:182:in `transaction'
 from /home/cmatthews/src/cannon/vendor/rails/activerecord/lib/active_record/transactions.rb:228:in `with_transaction_returning_status'
 from /home/cmatthews/src/cannon/vendor/rails/activerecord/lib/active_record/transactions.rb:196:in `save'
 from /home/cmatthews/src/cannon/vendor/rails/activerecord/lib/active_record/transactions.rb:208:in `rollback_active_record_state!'
 from /home/cmatthews/src/cannon/vendor/rails/activerecord/lib/active_record/transactions.rb:196:in `save'
4

3 に答える 3

17 
begin
  Event.create!(:name => 'Ironman Lanzarote 2011')
rescue ActiveRecord::RecordNotUnique => e
  # handle duplicate entry 
end

これは、Rails3で機能します。

于 2011-04-20T08:22:01.477 に答える
4

モデルに一意性制約を追加して、レコードがエラーとともに返され、無効になるようにすることができます。

例（レール2）：

class User < ActiveRecord::Base
  validates_uniqueness_of :email, :scope => [:name, :age]
end

または（Rails 3）

class User < ActiveRecord::Base
  validates :email, :uniqueness => {:scope => [:name, :age]}
end

これにより、次のようになります。

user1 = User.create :email => "one@example.com", :name => "one", :age => 20
user2 = User.create :email => "one@example.com", :name => "one", :age => 20
user2.valid? # false
于 2010-12-09T22:31:36.103 に答える
1

クエリを次のように変更できますか

INSERT IGNORE INTO `entries` ...

または、を検討することもできますINSERT... ON DUPLICATE KEY UPDATE...。

INSERTドキュメントはこちらです 。

于 2010-12-09T22:15:38.927 に答える