I am newbie to Rails. Now I have these files and a 'jobs.csv' file.
company.rb
class Company < ApplicationRecord
has_many :jobs, dependent: :destroy
end
job.rb
class Job < ApplicationRecord
belongs_to :company
def self.jobs_import
jobs = []
columns = [:title, :level, :salary, :description, :short_des, :requirement, :category, :company_id]
CSV.foreach(Rails.root.join("lib", "jobs.csv"), headers: true) do |row|
jobs << {title: row["name"], level: row["level"], salary: row["salary"], description: row["description"], short_des: row["benefit"], requirement: row["requirement"], category: row["type"]}
end
Job.import columns, jobs
end
end
Company migration files
create_table :companies do |t|
t.string :name
t.string :email, unique: true
t.text :description
t.string :address
t.string :company_code
t.timestamps
end
Job migration file
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
Now I want to import data to Job table that references to Job table. Please help me! Thanks!
UPDATE
Edit job.rb
jobs << {title: row["name"], level: row["level"], salary: row["salary"], description: row["description"], short_des: row["benefit"], requirement: row["requirement"], category: row["type"], company_id: Company.find_by(company_code: row["company id"])&.id}
Related
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!
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
I've just linked my Rails app to a mysql database which has the table names and columns in Spanish. Now I solved the Spanish table names problem by setting self.table_name = "table_name" inside the model.rb. Now the next problem occurs when I want to call a data through joining tables. In this case I'm trying to call all the ads that belong the first category. When I try this as you see in the screenshot below, I get this error. It sees the ad table now anuncio which is the Spanish name. I'm a bit confused, because I thought that by doing self.table_name = "table_name" in every model Rails knows which table I mean. Does someone know what's going on here and how to solve it? See below all my code regarding the models and tables.
Ad model:
class Ad < ApplicationRecord
self.table_name = "anuncios"
has_many :ad_copies
has_many :ad_addresses
has_many :relationships
has_many :magazines
has_many :categories, through: :relationships
belongs_to :user
end
Relationship model:
class Relationship < ApplicationRecord
self.table_name = "rel_anuncio"
self.primary_key = "id_anuncio"
belongs_to :ad, class_name: "anuncio", foreign_key: "id_anuncio", optional: true
belongs_to :category, class_name: "categoria", foreign_key: "id_categoria", optional: true
belongs_to :subcategory, class_name: "subcategoria", foreign_key: "id_subcategoria", optional: true
end
Category model:
class Category < ApplicationRecord
self.table_name = "categorias"
has_many :subcategories
has_many :relationships
has_many :ads, through: :relationships
belongs_to :user
end
Subcategory model:
class Subcategory < ApplicationRecord
self.table_name = "subcategorias"
has_many :relationships
has_many :ads, through: :relationships
belongs_to :category
end
You can see in the models above that I've been trying to get the relationship model to connect to the ad model with respectively the category and subcategory model, because these models have n:n relationship with each other. Before, when I was using an English database as practice, the #categories.first.ads.count worked, but changing to a Spanish database it suddenly stopped working. In the relationship table I'm also explicitly setting the foreign-key for each of the models.
Ads table (anuncios) schema:
create_table "anuncios", id: :integer, force: :cascade, options: "ENGINE=MyISAM DEFAULT CHARSET=utf8" do |t|
t.string "empresa", null: false
t.string "tel", null: false
t.string "fax_principal", null: false
t.string "movil_principal", null: false
t.string "email_principal", null: false
t.string "web", null: false
t.string "facebook", null: false
t.string "horario_v_principal", null: false
t.string "horario_i_principal", null: false
t.string "direccion_principal", null: false
t.string "poblacion_principal", null: false
t.string "activo", limit: 2, null: false
t.string "tam_anuncio", null: false
t.string "twitter", null: false
t.string "link", limit: 2, null: false
t.string "general", limit: 2, null: false
t.string "isla", limit: 10, null: false
t.string "subtitulo", null: false
t.string "comentario", null: false
t.datetime "modificacion", null: false
t.integer "promo1", default: 0, null: false
t.integer "promo2", default: 0, null: false
t.string "instagram", null: false
t.string "tel2", null: false
t.string "tel3", null: false
t.string "tel4", null: false
t.string "movil2", null: false
t.string "movil3", null: false
t.string "movil4", null: false
end
Relationship table (rel_anuncios) schema:
create_table "rel_anuncio", primary_key: ["id_anuncio", "id_categoria", "id_subcategoria"], force: :cascade, options: "ENGINE=MyISAM DEFAULT CHARSET=utf8" do |t|
t.integer "id_anuncio", null: false
t.integer "id_categoria", null: false
t.integer "id_subcategoria", null: false
t.integer "orden", null: false
end
Categories table (categorias) schema:
create_table "categorias", id: :integer, force: :cascade, options: "ENGINE=MyISAM DEFAULT CHARSET=utf8" do |t|
t.string "nombre", null: false
t.string "color", null: false
t.string "activo", limit: 2, null: false
t.string "bdd", limit: 7, null: false
t.integer "orden", null: false
t.integer "promoI", limit: 1, default: 0, null: false
t.integer "promoF", limit: 1, default: 0, null: false
t.integer "islas", limit: 1, default: 3, null: false
end
Subcategories table (subcategorias) schema:
create_table "subcategorias", id: :integer, force: :cascade, options: "ENGINE=MyISAM DEFAULT CHARSET=utf8" do |t|
t.integer "id_categoria", null: false
t.string "nombre", null: false
t.string "color", null: false
t.string "activo", limit: 2, default: "si", null: false
t.integer "orden", null: false
t.integer "promoI", limit: 1, default: 0, null: false
t.integer "promoF", limit: 1, default: 0, null: false
t.integer "islas", limit: 1, default: 3, null: false
end
UPDATE:
In response to #Jagdeep Singh comment I've changed my relationship.rb to look like this:
class Relationship < ApplicationRecord
self.table_name = "rel_anuncio"
self.primary_key = "id_anuncio"
belongs_to :ad, foreign_key: "id_anuncio", optional: true
belongs_to :category, foreign_key: "id_categoria", optional: true
belongs_to :subcategory, foreign_key: "id_subcategoria", optional: true
end
*I've taken away the class names.
After this change I get the following error:
Mysql2::Error: Unknown column 'rel_anuncio.category_id' in 'where clause': SELECT COUNT(*) FROM `anuncios` INNER JOIN `rel_anuncio` ON `anuncios`.`id` = `rel_anuncio`.`id_anuncio` WHERE `rel_anuncio`.`category_id` = 1
Here I can see that ActiveRecord is using in its sql statement category_id which should be id_categoria (see schema relationship table above). I have no idea how to make ActiveRecord use the right name for the foreign_key.
You class names should be the actual model names (and not their table names) when defining associations. And as your association names follow the rails conventions e.g. model for belongs_to :ad is Ad, and so on, you can omit specifying class_name:
class Relationship < ApplicationRecord
belongs_to :ad, foreign_key: "id_anuncio", optional: true
belongs_to :category, foreign_key: "id_categoria", optional: true
belongs_to :subcategory, foreign_key: "id_subcategoria", optional: true
end
Update
More changes in association definitions after the recent error posted in comments:
class Category < ApplicationRecord
has_many :subcategories, foreign_key: 'id_categoria'
has_many :relationships, foreign_key: 'id_categoria'
has_many :ads, through: :relationships
belongs_to :user
end
class Subcategory < ApplicationRecord
has_many :relationships, foreign_key: 'id_subcategoria'
has_many :ads, through: :relationships
belongs_to :category, foreign_key: 'id_categoria'
end
Ok guys, this might be a little bit confusing so stick with me. Let me start by introducing my tables. Basically I created four tables upon migration.
Students
Teachers
Subjects
Admin User
Here are my migration files:
Students:
def up
create_table :students, :id => false do |t|
t.integer "student_id",:primary_key => true
t.string "first_name", :limit => 25
t.string "last_name", :limit => 50
t.string "email", :default => ' ', :null => false
t.string "birthday"
t.string "subjects"
t.string "teachers"
t.string "username", :limit => 25
t.string "password_digest"
t.timestamps
end
Teachers:
def up
create_table :teachers, :id => false do |t|
t.integer "teacher_id", :primary_key => true
t.string "first_name"
t.string "last_name"
t.string "email", :default => ' ', :null => false
t.string "birthday"
t.string "subjects"
t.string "username", :limit => 25
t.string "password_digest"
t.timestamps
end
Subjects:
def up
create_table :subjects, :id => false do |t|
t.integer "subject_id", :primary_key => true
t.string "subject_name"
t.timestamps
end
end
Admin Users:
def up
create_table :admin_users, :id => false do |t|
t.integer "admin_user_id", :primary_key => true
t.string "username", :limit => 25
t.string "password_digest"
t.timestamps
end
end
So now let me get through the explanation. Basically:
one student can have many teachers
one teacher can have many students
one student can have many subjects
one teacher can teach many subjects
the admin can access all of this (create, edit, delete)
I created this fields and set them up on my models like this:
class Student < ApplicationRecord
has_and_belongs_to_many :subjects
has_and_belongs_to_many :teachers
has_many :admin_users
has_secure_password
self.primary_key = :student_id
end
class Teacher < ApplicationRecord
has_and_belongs_to_many :subjects
has_and_belongs_to_many :students
has_many :admin_users
has_secure_password
end
class Subject < ApplicationRecord
has_and_belongs_to_many :students
has_and_belongs_to_many :teachers
has_many :admin_users
# scope :search, lambda { |query| where(["name LIKE ?", "%#{query}%"])}
end
class AdminUser < ApplicationRecord
has_secure_password
scope :newest_first, lambda { order("created_at ASC") }
scope :oldest_first, lambda { order("created_at DESC") }
# scope :search, lambda { |query| where(["name LIKE ?", "%#{query}%"])}
end
Now I manually inserted data on mysql data record and then tried to pull up the records for student's subjects and teachers form fields.
How can I manage my database effectively esp teachers, students, and subjects??? Is there anything I need to do first to correlate the tables I have? Please help. Sorry for the long post. I am a newbie here. Appreciate your explanation (layman's term) and answers.
Check my models. Do I need to create a separate table to correlate teachers, students, and subjects?
Side Note: When I pull up my students and teachers field it gives me an error ActiveRecord_Associations_CollectionProxy:0x007f9c504361d0 ERROR.
I think this relation should work in your case:
Students:
def up
create_table :students, :id => false do |t|
t.integer "student_id",:primary_key => true
t.string "first_name", :limit => 25
t.string "last_name", :limit => 50
t.string "email", :default => ' ', :null => false
t.string "birthday"
t.string "subjects"
t.string "username", :limit => 25
t.string "password_digest"
t.timestamps
end
end
Ref: Generating auto increment with sequence 1001
Teachers:
def up
create_table :teachers, :id => false do |t|
t.integer "teacher_id", :primary_key => true
t.string "first_name"
t.string "last_name"
t.string "email", :default => ' ', :null => false
t.string "birthday"
t.string "subjects"
t.string "username", :limit => 25
t.string "password_digest"
t.timestamps
end
end
Subjects:
def up
create_table :subjects, :id => false do |t|
t.integer "subject_id", :primary_key => true
t.string "subject_name"
t.timestamps
end
end
Enrolled Subjects:
def up
create_table :enrolled_subjects, :id => false do |t|
t.integer "subject_id"
t.integer "teacher_id"
t.integer "student_id"
end
end
Model:
class Student < ApplicationRecord
has_many :enrolled_subjects
has_many :subjects, through: :enrolled_subjects
has_many :teachers, through: :enrolled_subjects
def teacher_names
self.teachers.map(&:first_name).join(", ")
end
end
class Teacher < ApplicationRecord
has_many :enrolled_subjects
has_many :subjects, through: :enrolled_subjects
has_many :students, through: :enrolled_subjects
end
class Subject < ApplicationRecord
has_many :enrolled_subjects
has_many :students, through: :enrolled_subjects
has_many :teachers, through: :enrolled_subjects
end
class EnrolledSubject < ActiveRecord::Base
belongs_to :student, foreign_key: :student_id
belongs_to :subject, foreign_key: :subject_id
belongs_to :teacher, foreign_key: :teacher_id
end
Example Repository
In development rake db:migrate works fine, generating a .sqlite3 file. In production where rake db:migrate adds tables to an actualy MySQL db I get the error.
-- create_table(:category_item_values)
rake aborted!
StandardError: An error has occurred, all later migrations canceled:
Index name 'index_category_item_values_on_category_item_key_id' on table 'category_item_values'
already exists/site/db/migrate/20151218040123_create_category_i
tem_values.rb:3:in `change'
Tasks: TOP => db:migrate
So clearly the index name index_category_item_values_on_category_item_key_id already exists but I dont know what to change to fix the problem or how the naming convention works in this case.
here is 20151218040123_create_category_item_values.rb
class CreateCategoryItemValues < ActiveRecord::Migration
def change
create_table :category_item_values do |t|
t.string :key
t.integer :key_type
t.integer :guide_id
t.integer :category_id
t.text :value
t.belongs_to :category_item_key, index: true
t.belongs_to :category_item, index: true
t.timestamps null: false
end
add_foreign_key :category_item_values, :category_items
add_index :category_item_values, :guide_id
add_index :category_item_values, :category_id
add_index :category_item_values, :key_type
add_index :category_item_values, :key
end
end
and
20160430043022_add_foreign_key_cat_keys_to_category_item_values.rb
class AddForeignKeyCatKeysToCategoryItemValues < ActiveRecord::Migration
def change
add_foreign_key :category_item_values, :category_item_keys
end
end
plus 20160111231051_create_category_item_keys.rb just incase the duplicate is in there
class CreateCategoryItemKeys < ActiveRecord::Migration
def change
create_table :category_item_keys do |t|
t.string :name
t.integer :key_type
t.integer :submitted_by
t.integer :approved_by
t.integer :guide_id
t.belongs_to :category, index: true
t.timestamps null: false
end
add_foreign_key :category_item_keys, :categories
add_index :category_item_keys, :name, unique: true
add_index :category_item_keys, :key_type
end
end
here is category_item_values table in the schema file
create_table "category_item_values", force: :cascade do |t|
t.string "key"
t.integer "key_type"
t.integer "guide_id"
t.integer "category_id"
t.text "value"
t.integer "category_item_key_id"
t.integer "category_item_id"
t.datetime "created_at", null: false
t.datetime "updated_at", null: false
t.string "slug"
end
add_index "category_item_values", ["category_id"], name: "index_category_item_values_on_category_id"
add_index "category_item_values", ["category_item_id"], name: "index_category_item_values_on_category_item_id"
add_index "category_item_values", ["category_item_key_id"], name: "index_category_item_values_on_category_item_key_id"
add_index "category_item_values", ["guide_id"], name: "index_category_item_values_on_guide_id"
add_index "category_item_values", ["key"], name: "index_category_item_values_on_key"
add_index "category_item_values", ["key_type"], name: "index_category_item_values_on_key_type"
add_index "category_item_values", ["slug"], name: "index_category_item_values_on_slug"
Whats clashing to cause this error?
I'm trying to make an application to store played FIFA games.
I'm having some trouble setting up the right associations.
I have 2 models at this time, User and Game.
SCHEMA:
ActiveRecord::Schema.define(version: 20160402112419) do
create_table "games", force: :cascade do |t|
t.integer "home_team_user_id"
t.integer "away_team_user_id"
t.string "home_score"
t.string "away_score"
t.integer "winner_id"
t.integer "loser_id"
t.datetime "created_at", null: false
t.datetime "updated_at", null: false
end
create_table "games_users", id: false, force: :cascade do |t|
t.integer "user_id"
t.integer "game_id"
end
add_index "games_users", ["user_id", "game_id"], name: "index_games_users_on_user_id_and_game_id"
create_table "users", force: :cascade do |t|
t.string "username"
t.string "email", default: "", null: false
t.string "encrypted_password", default: "", null: false
t.string "reset_password_token"
t.datetime "reset_password_sent_at"
t.datetime "remember_created_at"
t.integer "sign_in_count", default: 0, null: false
t.datetime "current_sign_in_at"
t.datetime "last_sign_in_at"
t.string "current_sign_in_ip"
t.string "last_sign_in_ip"
t.datetime "created_at", null: false
t.datetime "updated_at", null: false
end
add_index "users", ["email"], name: "index_users_on_email", unique: true
add_index "users", ["reset_password_token"], name: "index_users_on_reset_password_token", unique: true
end
MODELS:
class Game < ActiveRecord::Base
has_and_belongs_to_many :users
end
class User < ActiveRecord::Base
has_and_belongs_to_many :games
# Include default devise modules. Others available are:
# :confirmable, :lockable, :timeoutable and :omniauthable
devise :database_authenticatable, :registerable,
:recoverable, :rememberable, :trackable, :validatable
end
As you can see the "Games" table has 2 corresponding ID's:
home_team_user_id
away_team_user_id
These will store the user_id from the Users table, this is needed to calculate who's the winner corresponding with the score.
Console results:
irb(main):001:0> Game.last
Game Load (0.0ms) SELECT "games".* FROM "games" ORDER BY "games"."id" DESC LIMIT 1
=> #<Game id: 1, home_team_user_id: 1, away_team_user_id: 1, home_score: "1", away_score: "2", winner_id: 1, loser_id: 1, created_at: "2016-04-02 12:27:26", updated_at: "2016-04-02 12:27:26">
irb(main):002:0> game = Game.find(1)
Game Load (0.5ms) SELECT "games".* FROM "games" WHERE "games"."id" = ? LIMIT 1 [["id", 1]]
=> #<Game id: 1, home_team_user_id: 1, away_team_user_id: 1, home_score: "1", away_score: "2", winner_id: 1, loser_id: 1, created_at: "2016-04-02 12:27:26", updated_at: "2016-04-02 12:27:26">
irb(main):003:0> game.users
User Load (0.5ms) SELECT "users".* FROM "users" INNER JOIN "games_users" ON "users"."id" = "games_users"."user_id" WHERE "games_users"."game_id" = ? [["game_id", 1]]
=> #<ActiveRecord::Associations::CollectionProxy []>
I'm thinking now that the User.id needs to be linked to each individual corresponding id from the Games table.
How can I set this up? Do I need to use the has_many :through association?
UPDATE:
Could it be as simple as:
class User < ActiveRecord::Base
has_many :games, :foreign_key => "home_team_user_id"
has_many :games, :foreign_key => "away_team_user_id"
# Include default devise modules. Others available are:
# :confirmable, :lockable, :timeoutable and :omniauthable
devise :database_authenticatable, :registerable,
:recoverable, :rememberable, :trackable, :validatable
end
class Game < ActiveRecord::Base
belongs_to :user, :foreign_key => "home_team_user_id"
belongs_to :user, :foreign_key => "away_team_user_id"
end
Because actually a User has many games but in that game he only has one team, the home or away team. In this logic I assigned the user_id to one of the custom foreign fields.
You can achieve this like :
class User < ActiveRecord::Base
has_many :home_games, class_name: 'Game', foreign_key: 'home_team_user_id'
has_many :away_games, class_name: 'Task', foreign_key: 'away_team_user_id'
end
class Game < ActiveRecord::Base
belongs_to :home_user, class_name: "User", foreign_key: "home_team_user_id"
belongs_to :away_user, class_name: "User", foreign_key: "away_team_user_id"
# Rails anticipate foreign keys itself so, addig `foreign_keys` is not
# necessary in this class as we've already mentioned `belongs_to :home_user`
end