mysql - Hr#internal_employee_page 中的 ActiveRecord::StatementInvalid

Question

我是 ruby​​ on Rails 的学习者，我想加入两个模型(表)。User.rb(用户表)

class User < ActiveRecord::Base has_many :offer_letters end

OfferLetter.rb(offer_letter表)

class OfferLetter < ActiveRecord::Base belongs_to :user end

HrController(hr_controller.rb)

class HrController < ApplicationController
    def internal_employee_page
        @employees = OfferLetter.joins(:user).where(:id => :candidate_id)       
end

结束

运行我的代码时出现错误“Mysql2::Error: Unknown columns 'offer_letters.user_id' in 'on Clause': SELECT offer_letters.* FROM offer_letters INNER JOIN users ON users.id = offer_letters.user_id WHERE offer_letters .id = NULL”

<div id="job_details">
    <% @employees.each do |emp| %>
       <%= render partial: "hr/employee_details", locals: {emp: emp} %>
    <% end %>               
</div>

此行错误:<% @employees.each do |emp| %>所以请告诉我哪里错了

Answer 1

当我们使用连接时，我们必须指定表名(应该是复数)及其属性。因此，在您的 where 子句中，请指定 id 及其各自的表，例如:

@employees = OfferLetter.joins(:user).where('users.id = ?', candidate_id)

或者

@employees = OfferLetter.joins(:user).where('offer_letters.id = ?', candidate_id)