2015-12-17から1日間の記事一覧
http://stackoverflow.com/questions/4870961/rails-validate-uniqueness-of-multiple-columns validates :attr, uniqueness: {scope: [:attr1, ... , :attrn]}
http://stackoverflow.com/questions/4870961/rails-validate-uniqueness-of-multiple-columns validates :attr, uniqueness: {scope: [:attr1, ... , :attrn]}