Rails create data in has_many :through relation - mysql

Question

I have these file and a CSV file. Now I want to
job.rb
class Job < ApplicationRecord
has_many :city_jobs
has_many :cities, through: :city_jobs
end
city.rb
class City < ApplicationRecord
has_many :city_jobs
has_many :jobs, through: :city_jobs
end
city_jobs.rb
class CityJob < ApplicationRecord
belongs_to :city
belongs_to :job
end
migration files
create_table :jobs do |t|
t.string :title
t.string :level
t.string :salary
t.string :other_salary
t.text :description
t.text :short_des
t.text :requirement
t.integer :category
t.datetime :post_date
t.datetime :expiration_date
t.references :company, foreign_key: true
t.timestamps
end
create_table :cities do |t|
t.string :name, unique: true
t.string :region
t.timestamps
end
create_table :city_jobs do |t|
t.references :city, foreign_key: true
t.references :job, foreign_key: true
t.timestamps
end
Import.rb
require "csv"
class JobsImport
def import_job
jobs = []
cities = []
job_columns = [:title, :level, :salary, :description, :short_des,
:requirement, :category, :company_id]
city_columns = [:name, :region]
CSV.foreach(Rails.root.join("lib", "jobss.csv"), headers: true) do |row|
cities << {name: row["company province"], region: "Việt Nam"}
jobs << JobCsv.new(row).csv_attributes
end
City.import city_columns, cities, on_duplicate_key_ignore: true
Job.import job_columns, jobs
puts "Data imported"
end
end
I have imported City and Job from CSV to database. Now how can I create data to City_jobs table that keep cities_id and jobs_id? Please help me! Thank you!

Answer 1

You can iterate through the CSV file again to connect the two tables.
CSV.foreach(Rails.root.join("lib", "jobss.csv"), headers: true) do |row|
city = City.find_by(name: row["company province"])
job = Job.find_by(JobsCsv.new(row).csv_attributes)
city.jobs << job
end