Question

I created two rails apps sample and test. There are two databases. users table in sample app with the field report_id refers to reports table in test app.

I want to display the test app data in sample app by fetching the unique_id field. I want to display reports data for a particular user by connecting these two databases.

How can I achieve this in the simplest way?

Answer 1

对于rails6，您可以提供两个连接并为每个连接指定数据库，例如

  adapter: postgresql
  encoding: unicode
  username: username
  password: password
  pool: 5
  host: localhost

development:
  primary:
    <<: *default
    database: database1
    adapter: postgresql
  secondary:
    <<: *default
    database: database2
    adapter: postgresql

在生产环境中，您可以使用数据库url之类的

  primary:
    url: <%= ENV['DATABASE_URL'] %>

  secondary:
    url: <%= ENV['SECONDARY_DATABASE_URL'] %>

Answer 2

You can connect to two databases from each rails project:

#config/sabple_database.yml
default: &default  
  encoding: utf8
  adapter: mysql2
  port: 5500

development:  
  <<: *default
  database: sample_db
  host:
  username:
  password:


#config/initializers/sample_database.rb
SAMPLE_DB = YAML.load_file(File.join(Rails.root, "config", "sample_database.yml"))[Rails.env.to_s]

#models
class SampleDbBase < ActiveRecord::Base  
  self.abstract_class = true
  establish_connection SAMPLE_DB
end

#models/my_model.rb
class MyModel < SampleDbBase 
end

Read more about that. So, then you can create the same models without migration(allows using Reports.find(report_id)).

Also, you can write a query to some database using ActiveRecord::Base.establish_connection and execute.

Answer 3

感谢rails 6. rails 6将默认提供多数据库连接。请使用GitHub版本的rails。并配置数据库。yml：

development:
  primary:
  <<: *default
  database: multiple_databases_development
  animals:
  <<: *default
  database: multiple_databases_development_animals
  migrations_paths: "db/animals_migrate"

有关更多详细信息，请查看https://github.com/eileencodes/multiple_databases_demo

How to connect two rails projects

3 个答案: