我有一个Rails 7应用程序，我试图有条件地连接到不同的数据库。
下面是database.yml

development:
  primary:
    adapter: postgresql
    database: development
    host: localhost
    user: postgres
    password: root
  main_red:
    adapter: postgresql
    username: etl
    database: "<%= ENV['API_MAIN_DATABASE_NAME'] %>"
    password: "<%= ENV['API_DATABASE_PASSWORD'] %>"
    host: "<%= ENV['API_DATABASE_HOST'] %>"
    database_tasks: false
  main_blue:
    adapter: postgresql
    username: etl
    database: "<%= ENV['API_MAIN_DATABASE_NAME'] %>"
    password: "<%= ENV['API_DATABASE_PASSWORD'] %>"
    host: "<%= ENV['API_DATABASE_HOST'] %>"
    database_tasks: false
  main_green:
    adapter: postgresql
    username: etl
    database: "<%= ENV['API_MAIN_DATABASE_NAME'] %>"
    password: "<%= ENV['API_DATABASE_PASSWORD'] %>"
    host: "<%= ENV['API_DATABASE_HOST'] %>"
    database_tasks: false

下面是模型定义

class ExternalRecord < ApplicationRecord
  self.abstract_class = true
  #establish_connection :main
  connects_to database: {main_red: :main_red, main_green: :main_green, main_blue: :main_blue}
end

我想从main_red, main_green or main_blue中执行读取，并在primary数据库中执行插入。
下面是我的代码

ActiveRecord::Base.connected_to(role: :main_red) do
            result = Api::V2::BulkExport.where(Tier: @tier, Version: 'v2').order(order).ransack(@params[:q]).result.limit(@limit)
          end
track_usage(user_id: @user.id, end_point: request.path, rows_returned: result.count)

从数据库的阅读按预期工作，但看起来我无法连接回主数据库。我看到以下错误

ActiveRecord::ConnectionNotEstablished (No connection pool for 'ExternalRecord' found.):

任何帮助这将是伟大的，谢谢。