I want to delete a table in my schema. I created the database when I first started the project and want the table removed. What is the best way of doing this?
I tried rails g migration drop table :installs but that just creates a empty migration?
Schema:
create_table "installs", force: :cascade do |t|
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 "installs", ["email"], name: "index_installs_on_email", unique: true
add_index "installs", ["reset_password_token"], name: "index_installs_on_reset_password_token", unique: true
If you create an empty migration by running:
rails g migration DropInstalls
or:
rails generate migration DropInstalls
You can then add this into that empty migration:
class DropInstalls < ActiveRecord::Migration
def change
drop_table :installs
end
end
Then run rake db:migrate in the command line which should remove the Installs table
Note: db/schema.rb is an autogenerated file. To alter the db structure, you should use the migrations instead of attempting to edit the schema file.
Related
I have started my project with a Users table and have since migrated to using an Accounts table. In the process I have an old reference to the Users table still in my schema.rb file and I need to remove it and create a new reference, or update the reference.
I am trying to work out a migration that will allow me to do this, however it keeps throwing an error as there's no Users table and when it did exist, it never had an account_id , which you can see referenced in my schema.rb file.
I really just need my schema.rb file to update
"add_foreign_key "likes", "users", column: "account_id"
to
add_foreign_key "likes", "accounts", column: "account_id"
But am finding this impossible to do with a migration without generating an error.
Any suggestions?
ActiveRecord::Schema.define(version: 2022_01_18_013836) do
create_table "accounts", force: :cascade do |t|
t.string "email", default: "", null: false
t.string "encrypted_password", default: "", null: false
t.string "reset_password_token"
t.datetime "reset_password_sent_at", precision: 6
t.datetime "remember_created_at", precision: 6
t.datetime "created_at", precision: 6, null: false
t.datetime "updated_at", precision: 6, null: false
t.string "username"
t.string "first_name"
t.string "last_name"
t.index ["email"], name: "index_accounts_on_email", unique: true
t.index ["reset_password_token"], name: "index_accounts_on_reset_password_token", unique: true
end
create_table "likes", force: :cascade do |t|
t.integer "account_id", null: false
t.integer "product_id", null: false
t.datetime "created_at", precision: 6, null: false
t.datetime "updated_at", precision: 6, null: false
t.index ["account_id"], name: "index_likes_on_account_id"
t.index ["product_id"], name: "index_likes_on_product_id"
end
create_table "products", force: :cascade do |t|
t.string "product_name"
t.string "product_category"
t.string "product_type"
t.string "product_image"
t.datetime "created_at", precision: 6, null: false
t.datetime "updated_at", precision: 6, null: false
t.text "product_description"
t.string "product_country"
end
add_foreign_key "likes", "products"
add_foreign_key "likes", "users", column: "account_id"
end
Best way to resolve this is to create a migration that adds users back with only account_id then remove the foreign key, and drop the user table again.
Should be doable in 1 migration, however I went about it as follows.
I ended up creating a new Users table with just an account_id:integer
Created a migration to remove_foreign_key
Then created a migration to then drop that Users table again.
Schema file is looking correct now and I have all the migrations to trace my changes.
I am using ruby 2.7 and Rails version 6.0.2.1
When I try to test my model I get this message
Error:
OfferTest#test_valid_offer:
DRb::DRbRemoteError: PG::UndefinedTable: ERROR: relation "views" does not exist
LINE 8: WHERE a.attrelid = '"views"'::regclass
^
(ActiveRecord::StatementInvalid)
rails test test/models/offer_test.rb:4
This is my schema file:
ActiveRecord::Schema.define(version: 2020_01_20_105655) do
# These are extensions that must be enabled in order to support this database
enable_extension "plpgsql"
create_table "offers", force: :cascade do |t|
t.string "city"
t.string "area"
t.string "address"
t.string "contact_person"
t.string "contact_person_phone"
t.string "denomination"
t.string "category"
t.string "typology"
t.integer "guests"
t.integer "rooms"
t.boolean "lift"
t.decimal "expense"
t.datetime "created_at", precision: 6, null: false
t.datetime "updated_at", precision: 6, null: false
end
create_table "requests", force: :cascade do |t|
t.string "name"
t.string "last_name"
t.string "address"
t.decimal "budget"
t.date "date_of_request"
t.string "document_id"
t.string "phone"
t.string "residential_address"
t.date "date_of_birth"
t.string "notes"
t.datetime "created_at", precision: 6, null: false
t.datetime "updated_at", precision: 6, null: false
end
create_table "users", force: :cascade do |t|
t.string "name", null: false
t.string "last_name", null: false
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.datetime "created_at", precision: 6, null: false
t.datetime "updated_at", precision: 6, null: false
t.index ["email"], name: "index_users_on_email", unique: true
t.index ["reset_password_token"], name: "index_users_on_reset_password_token", unique: true
end
end
Ad of now I have 3 tables. I am testing the Offer model but I get this strange behaviour.
This is my test model code
require 'test_helper'
class OfferTest < ActiveSupport::TestCase
test "valid offer" do
offer = Offer.new(city: "Rome", area: "Zona Sud", address: "Via Roma")
end
end
I've already run rails db:test:prepare but I cannot fix this issue.
My initial thought is that some gem is injecting behaviour into your models.
Something is expecting a table "views". The name views hints at either a gem using database views to virtualize tables, or some gem that works in the domain with views: for example a gem for statistics (An order has been viewed 21 times: has 21 views).
I'd suggest removing all gems from your gemfile and re-including them one by one. This will tell you what gem is injecting this behaviour: knowing what your dependencies do is an important part of building an app, IMO.
If it is a gem, that gem most probably has some migrations that you need to install and run:
bundle exec rake railties:install:migrations
bundle exec rake db:migrate
I have seen this question posted several times and the solution is always to drop the database and recreate it. I have data in my database and hence do not want to do that.
Schema:
create_table "users", force: :cascade do |t|
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.datetime "created_at", null: false
t.datetime "updated_at", null: false
t.string "product_id"
end
My second to last migration file:
class AddProductIdToUsers < ActiveRecord::Migration[5.2]
def change
add_column :users, :product_id, :string
end
end
I have no other migration file that creates a product_id column on my current branch.
I have multiple branches with different database schema. I am wondering if that caused the issue. The branch that might have created the product_id is only there for reference now. It will not be merged to master.
How do I fix this issue? I have tried:
rake db:rollback step=3
rake db:migrate
but that did not work.
Your create_table is already creating product_id inside the database.
create_table "users", force: :cascade do |t|
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.datetime "created_at", null: false
t.datetime "updated_at", null: false
t.string "product_id" // <- note this line
end
And you are trying to add another column of same name in your table, which raises an error.
I am building a small rails app. When, I run heroku run rake db:migrate, I get this error
rake aborted!
StandardError: An error has occurred, this and all later migrations canceled:
PG::UndefinedTable: ERROR: relation "categories" does not exist
: CREATE TABLE "habits" ("id" serial primary key, "name" character varying, "description" character varying, "category_id" integer, "user_id" integer, "created_at
" timestamp NOT NULL, "updated_at" timestamp NOT NULL, CONSTRAINT "fk_rails_23642321ab"
FOREIGN KEY ("category_id")
REFERENCES "categories" ("id")
, CONSTRAINT "fk_rails_541267aaf9"
FOREIGN KEY ("user_id")
REFERENCES "users" ("id")
)
In attempt to solve it, I also added this to inflections.rb
ActiveSupport::Inflector.inflections do |inflect|
inflect.irregular 'category', 'categories'
inflect.plural 'category', 'categories'
end
Which didn't help.
I also looked at few answers on stackoverflow including this, but it didn't help because I am getting this error when I run migration command.
Here is my migration files for categories and habits.
class CreateCategories < ActiveRecord::Migration[5.0]
def change
create_table :categories do |t|
t.string :name
t.timestamps
end
end
end
class CreateHabits < ActiveRecord::Migration[5.0]
def change
create_table :habits do |t|
t.string :name
t.string :description
t.integer :user_id
t.integer :category_id
t.timestamps
end
end
end
Here is my schema.rb
# This file is auto-generated from the current state of the database. Instead
# of editing this file, please use the migrations feature of Active Record to
# incrementally modify your database, and then regenerate this schema definition.
#
# Note that this schema.rb definition is the authoritative source for your
# database schema. If you need to create the application database on another
# system, you should be using db:schema:load, not running all the migrations
# from scratch. The latter is a flawed and unsustainable approach (the more migrations
# you'll amass, the slower it'll run and the greater likelihood for issues).
#
# It's strongly recommended that you check this file into your version control system.
ActiveRecord::Schema.define(version: 20170612231416) do
create_table "categories", force: :cascade do |t|
t.string "name"
t.datetime "created_at", null: false
t.datetime "updated_at", null: false
end
create_table "comments", force: :cascade do |t|
t.text "description"
t.integer "habit_id"
t.integer "user_id"
t.datetime "created_at", null: false
t.datetime "updated_at", null: false
end
create_table "goals", force: :cascade do |t|
t.string "name"
t.datetime "created_at", null: false
t.datetime "updated_at", null: false
end
create_table "goals_habits", force: :cascade do |t|
t.integer "habit_id"
t.integer "goal_id"
t.datetime "created_at", null: false
t.datetime "updated_at", null: false
end
create_table "goals_milestones", force: :cascade do |t|
t.integer "goal_id"
t.integer "milestone_id"
t.datetime "created_at", null: false
t.datetime "updated_at", null: false
end
create_table "habits", force: :cascade do |t|
t.string "name"
t.string "description"
t.integer "user_id"
t.integer "category_id"
t.datetime "created_at", null: false
t.datetime "updated_at", null: false
end
create_table "milestones", force: :cascade do |t|
t.string "description"
t.datetime "created_at", null: false
t.datetime "updated_at", null: false
end
create_table "milestones_statuses", force: :cascade do |t|
t.integer "milestone_id"
t.integer "status_id"
t.datetime "created_at", null: false
t.datetime "updated_at", null: false
end
create_table "statuses", force: :cascade do |t|
t.string "description"
t.datetime "created_at", null: false
t.datetime "updated_at", null: false
end
create_table "users", force: :cascade do |t|
t.string "name"
t.string "email"
t.string "password_digest"
t.datetime "created_at", null: false
t.datetime "updated_at", null: false
t.integer "role"
end
end
Not sure what more I am missing!
It seems there is a problem with your migrations. Run this locally to see if they run without a problem: rake db:drop && rake db:create && rake db:migrate
PS: I don't tell you to run rake db:reset because that loads the schema instead of running the migrations.
It kind of seems like your migrations files are the problem. Perhaps try rake db:schema:load instead. I have had similar problems before and it is always because of a column added after the initial migration.
Finally, I just had to destroy my Heroku app and recreate it. That solved this problem. I didn't have much data in my app. So, I could do it. If you have a really good database, I wouldn't suggest it.
To destroy app, heroku apps:destroy
And to create it again, heroku create appname
Very odd problem
I am trying to migrate my database but I keep getting:
PG::UndefinedTable: ERROR: relation "users" does not exist
Here is my migration:
class AddRoleToUser < ActiveRecord::Migration
def up
add_column :users, :role_id, :integer
end
def down
remove_column :users, :role_id
end
end
And my schema:
ActiveRecord::Schema.define(version: 20140205191602) do
# These are extensions that must be enabled in order to support this database
enable_extension "plpgsql"
create_table "horseraces", force: true do |t|
t.integer "horse_id"
t.integer "race_id"
t.datetime "entered"
t.datetime "created_at"
t.datetime "updated_at"
end
create_table "horses", force: true do |t|
t.string "name"
t.string "gender"
t.date "DOB"
t.datetime "created_at"
t.datetime "updated_at"
end
create_table "races", force: true do |t|
t.string "name"
t.integer "race_number"
t.string "description"
t.datetime "created_at"
t.datetime "updated_at"
end
create_table "roles", force: true do |t|
t.string "name"
t.datetime "created_at"
t.datetime "updated_at"
end
create_table "users", force: true do |t|
t.string "first_name"
t.string "last_name"
t.string "user_name"
t.string "address"
t.string "phone_number"
t.string "email", default: ""
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"
t.datetime "updated_at"
t.integer "role_id"
end
add_index "users", ["email"], name: "index_users_on_email", unique: true, using: :btree
add_index "users", ["reset_password_token"], name: "index_users_on_reset_password_token", unique: true, using: :btree
end
I have been trying:
rake db:reset
and
rake db:drop
rake db:create
rake db:migrate
And I get met with the same errors each time.
Interesting that this was working, meaning I had run these commands and got it working. I simply tried to just start fresh and now it's throwing these errors.
Worth noting - I did change a model file from users.rb to user.rb & roles.rb to role.rb I don't know if this would effect anything.
Any help would be much appreciated.
You should load the schema first then migrate:
rake db:schema:load
rale db:migrate
The first command will run your schema.rb file and create the users table. The 2nd will then run your migration and it shouldn't fail because now the users table exists.
This sort of thing often happens when you go back and edit your migrations... might not be exactly what went wrong for you - but it's the first thing that I'd suspect. My strongest suspicion would be that you somehow deleted your "create_users" migration.