如何在Rails中访问数据库的内容？

Question

Okay so I have model, and I populated my sqlite database in my seeds.rb here is the code

~/PeriodicTable/db/seeds.rb

# The data can then be loaded with the rake db:seed (or created alongside the db with db:setup).
#
# Examples:
#
#   cities = City.create([{ name: 'Chicago' }, { name: 'Copenhagen' }])
#   Mayor.create(name: 'Emanuel', city: cities.first)
File.open("pt-data3.csv", 'r').each_line do |line|
    temp = line.split(',')
    Element.create(proton: temp[0].strip, symbol: temp[1].strip, name: temp[2].strip, mass: temp[3].strip)
end

Then I tried to access it in my rspec and I keep getting nil, this is my rspec

~/PeriodicTable/spec/models/element_spec.rb

require 'rails_helper'

RSpec.describe Element, :type => :model do
    it "should contain the right elements" do
        expect(Element.find_by(proton: 1)).to include("Hydrogen")
    end
end

However Element.find_by keep returning nil no matter what I put in. My database is populated for sure because I checked. When I do Element.find_by in my rails console it works just fine. I can get all the elements correctly in my rails console however when I put it anywhere in my rails app Element.find_by always returns nil

here is also my model class if its any relevance

~/PeriodicTable/app/models/element.rb

class Element < ActiveRecord::Base
end

Answer 1

Rails maintains different db's for production, development, and test. This means that the data you think should be there exists in your development db. If you want to access data in tests, you need to save it in your testing environment. Consider using FactoryGirl to create objects in your test database.