Rails的「創建或更新」模式

Question

我有以下代碼：

FluidsurveysSurvey.all do |survey| 
    ResponseSummary.where(:survey_id => survey.id).first_or_create do |response_summary| 
    response_summary.count = count 
    end 
end 

我認爲，這要麼找到ResponseSummary與給定survey.id，或創建並添加count。問題是無論如何我都想更新count。因此，如果找到具有該survey_id的ResponseSummary，請更新count。否則，請創建ResponseSummary並更新count。我正在使用Rails 4.0。

Answer 1

如果你想在新創建的帳戶述略ID：

FluidsurveysSurvey.all do |survey| 
    response = ResponseSummary.find_or_create_by_servey_id(survey.id) 
response.update_column(:count, count) 
end 

如果你不希望在新創建的帳戶servey_id：

FluidsurveysSurvey.all do |survey| 
    response = ResponseSummary.find_by_servey_id(survey.id)||ResponseSummary.create 
response.update_column(:count, count) 
end