Ruby on Rails 데이터베이스 제거 또는 재생성

Ruby on Rails 데이터베이스 제거 또는 재생성

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데이터로 가득 찬 dev Ruby on Rails 데이터베이스가 있습니다. 모든 것을 삭제하고 데이터베이스를 다시 만들고 싶습니다. 다음과 같은 것을 사용할 생각입니다.

rake db:recreate

이것이 가능한가?

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이 작업을 수행하는 두 가지 방법을 알고 있습니다.

이렇게하면 데이터베이스가 재설정되고 현재 스키마가 모두 다시로드됩니다.

rake db:reset db:migrate

그러면 db가 파괴되고 생성 된 다음 현재 스키마가 마이그레이션됩니다.

rake db:drop db:create db:migrate

두 시나리오 모두에서 모든 데이터가 손실됩니다.

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Rails 4에서 필요한 모든 것은

$ rake db:schema:load

이렇게하면 모든 마이그레이션을 하나씩 적용 할 필요없이 DB의 전체 내용이 삭제되고 schema.rb 파일에서 스키마가 다시 생성됩니다.

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나는 터미널에서 다음과 같은 하나의 라이너를 사용합니다.

$ rake db:drop && rake db:create && rake db:migrate && rake db:schema:dump && rake db:test:prepare

나는 이것을 셸 별칭으로 넣고 이름을 지정했습니다. remigrate

이제 Rails 작업을 쉽게 "체인"할 수 있습니다.

$ rake db:drop db:create db:migrate db:schema:dump db:test:prepare # db:test:prepare no longer available since Rails 4.1.0.rc1+

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업데이트 : Rails 5에서는 다음 명령을 통해이 명령에 액세스 할 수 있습니다.

rails db:purge db:create db:migrate RAILS_ENV=test

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최신 Rails 4.2 릴리스부터 다음을 실행할 수 있습니다.

rake db:purge 

출처 : commit

# desc "Empty the database from DATABASE_URL or config/database.yml for the current RAILS_ENV (use db:drop:all to drop all databases in the config). Without RAILS_ENV it defaults to purging the development and test databases."
  task :purge => [:load_config] do
    ActiveRecord::Tasks::DatabaseTasks.purge_current
  end

위에서 언급 한 것처럼 함께 사용할 수 있습니다.

rake db:purge db:create db:migrate RAILS_ENV=test

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원하는 항목에 따라 다음을 사용할 수 있습니다.

rake db:create

… 처음부터 데이터베이스를 구축하려면 config/database.yml, 또는…

rake db:schema:load

… schema.rb파일 에서 처음부터 데이터베이스를 구축 합니다.

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일련의 단계를 실행하십시오. 데이터베이스를 삭제 한 다음 다시 생성하고 데이터를 마이그레이션하고 시드가있는 경우 데이터베이스를 심습니다.

rake db:drop db:create db:migrate db:seed

의 기본 환경 rake은 development 이므로 사양 테스트에서 예외가 발견 되면 다음과 같이 테스트 환경에 대한 db를 다시 만들어야 합니다.

RAILS_ENV=test rake db:drop db:create db:migrate

대부분의 경우 테스트 데이터베이스는 테스트 절차 중에 파종되므로 db:seed작업 조치를 통과 할 필요가 없습니다. 그렇지 않으면 데이터베이스를 준비해야합니다.

rake db:test:prepare

또는

RAILS_ENV=test rake db:seed

Additionally, to use the recreate task you can add into Rakefile the following code:

namespace :db do
   task :recreate => [ :drop, :create, :migrate ] do
      if ENV[ 'RAILS_ENV' ] !~ /test|cucumber/
         Rake::Task[ 'db:seed' ].invoke
      end
   end
end

Then issue:

rake db:recreate

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From the command line run

rake db:migrate:reset

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Use like

rake db:drop db:create db:migrate db:seed

All in one line. This is faster since the environment doesn't get reloaded again and again.

db:drop - will drop database.

db:create - will create database (host/db/password will be taken from config/database.yml)

db:migrate - will run existing migrations from directory (db/migration/.rb)*.

db:seed - will run seed data possible from directory (db/migration/seed.rb)..

I usually prefer:

rake db:reset

to do all at once.

Cheers!

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You can manually do:

rake db:drop
rake db:create
rake db:migrate

Or just rake db:reset, which will run the above steps but will also run your db/seeds.rb file.

An added nuance is that rake db:reset loads directly from your schema.rb file as opposed to running all the migrations files again.

You data gets blown away in all cases.

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You can use this following command line:

rake db:drop db:create db:migrate db:seed db:test:clone

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To drop a particular database, you can do this on rails console:

$rails console
Loading development environment
1.9.3 > ActiveRecord::Migration.drop_table(:<table_name>)
1.9.3 > exit

And then migrate DB again

$bundle exec rake db:migrate 

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On rails 4.2, to remove all data but preserve the database

$ bin/rake db:purge && bin/rake db:schema:load

https://github.com/rails/rails/blob/4-2-stable/activerecord/CHANGELOG.md

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You can use db:reset - for run db:drop and db:setup or db:migrate:reset - which runs db:drop, db:create and db:migrate.

dependent at you want to use exist schema.rb

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According to Rails guide, this one liner should be used because it would load from the schema.rb instead of reloading the migration files one by one:

rake db:reset

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Because in development , you will always want to recreate the database,you can define a rake task in your lib/tasks folder like that.

  namespace :db do
      task :all => [:environment, :drop, :create, :migrate] do
   end 
end

and in terminal you will run

rake db:all

it will rebuild your database

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I think the best way to run this command:

**rake db:reset** it does db:drop, db:setup
 rake db:setup does db:create, db:schema:load, db:seed

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Simply you can run

rake db:setup

It will drop database, create new database and populate db from seed if you created seed file with some data.

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3 options, same result:

1. All steps:

  $ rake db:drop           # deletes the database for the current env
  $ rake db:create         # creates the database for the current env
  $ rake db:schema:load    # loads the schema already generated from schema.rb / erases data
  $ rake db:seed           # seed with initial data

2. Reset:

  $ rake db:reset          # drop / schema:load / seed

3. Migrate:reset:

  $ rake db:migrate:reset  # drop / create / migrate
  $ rake db:seed

Notes:

• If schema:load is used is faster than doing all migrations, but same result.
• All data will be lost.
• You can run multiple rakes in one line.
• Works with rails 3.

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I've today made quite a few changes to my rails schema. I realised I needed an additional two models in a hierarchy and some others to be deleted. There were many little changes required to the models and controllers.

I added the two new models and created them, using:

rake db:migrate

Then I edited the schema.rb file. I manually removed the old models that were no longer required, changed the foreign key field as required and just reordered it a bit to make it clearer to me. I deleted all the migrations, and then re-ran the build via:

rake db:reset

It worked perfectly. All the data has to be reloaded, of course. Rails realised the migrations had been deleted and reset the high-water mark:

-- assume_migrated_upto_version(20121026094813, ["/Users/sean/rails/f4/db/migrate"])

참고URL : https://stackoverflow.com/questions/4116067/purge-or-recreate-a-ruby-on-rails-database