Question

当我尝试通过ruby脚本运行SQL时遇到了错误。有人可以帮我找出可能的原因吗？我已经找了一些类似的帖子，但还没找到合适的解决方案。

    /Users/User/.rbenv/versions/2.4.3/lib/ruby/2.4.0/rubygems/core_ext/kernel_require.rb:68:in `require': Could not load 'active_record/connection_adapters/redshift_adapter'. Make sure that the adapter in config/database.yml is valid. If you use an adapter other than 'mysql', 'mysql2', 'postgresql' or 'sqlite3' add the necessary adapter gem to the Gemfile. (LoadError)
  from /Users/User/.rbenv/versions/2.4.3/lib/ruby/2.4.0/rubygems/core_ext/kernel_require.rb:68:in `require'
  from /Users/User/.rvm/gems/ruby-2.4.3/gems/activesupport-4.2.10/lib/active_support/dependencies.rb:274:in `block in require'
  from /Users/User/.rvm/gems/ruby-2.4.3/gems/activesupport-4.2.10/lib/active_support/dependencies.rb:240:in `load_dependency'
  from /Users/User/.rvm/gems/ruby-2.4.3/gems/activesupport-4.2.10/lib/active_support/dependencies.rb:274:in `require'
  from /Users/User/.rvm/gems/ruby-2.4.3/gems/pg-0.17.1/lib/pg.rb:4:in `<top (required)>'
  from /Users/User/.rbenv/versions/2.4.3/lib/ruby/2.4.0/rubygems/core_ext/kernel_require.rb:68:in `require'
  from /Users/User/.rbenv/versions/2.4.3/lib/ruby/2.4.0/rubygems/core_ext/kernel_require.rb:68:in `require'
  from /Users/User/.rvm/gems/ruby-2.4.3/gems/activesupport-4.2.10/lib/active_support/dependencies.rb:274:in `block in require'
  from /Users/User/.rvm/gems/ruby-2.4.3/gems/activesupport-4.2.10/lib/active_support/dependencies.rb:240:in `load_dependency'
  from /Users/User/.rvm/gems/ruby-2.4.3/gems/activesupport-4.2.10/lib/active_support/dependencies.rb:274:in `require'
  from /Users/User/.rvm/gems/ruby-2.4.3/gems/activerecord4-redshift-adapter-0.2.1/lib/active_record/connection_adapters/redshift_adapter.rb:17:in `<top (required)>'
  from /Users/User/.rbenv/versions/2.4.3/lib/ruby/2.4.0/rubygems/core_ext/kernel_require.rb:133:in `require'
  from /Users/User/.rbenv/versions/2.4.3/lib/ruby/2.4.0/rubygems/core_ext/kernel_require.rb:133:in `rescue in require'
  from /Users/User/.rbenv/versions/2.4.3/lib/ruby/2.4.0/rubygems/core_ext/kernel_require.rb:39:in `require'
  from /Users/User/.rvm/gems/ruby-2.4.3/gems/activesupport-4.2.10/lib/active_support/dependencies.rb:274:in `block in require'
  from /Users/User/.rvm/gems/ruby-2.4.3/gems/activesupport-4.2.10/lib/active_support/dependencies.rb:240:in `load_dependency'
  from /Users/User/.rvm/gems/ruby-2.4.3/gems/activesupport-4.2.10/lib/active_support/dependencies.rb:274:in `require'
  from /Users/User/.rvm/gems/ruby-2.4.3/gems/activerecord-4.2.10/lib/active_record/connection_adapters/connection_specification.rb:175:in `spec'
  from /Users/User/.rvm/gems/ruby-2.4.3/gems/activerecord-4.2.10/lib/active_record/connection_handling.rb:50:in `establish_connection'
  from /Users/User/Desktop/github/tracker/app/workers/appsflyer_importer_worker_aggregate.rb:100:in `fetch_data'
  from /Users/User/Desktop/github/tracker/app/workers/appsflyer_importer_worker_aggregate.rb:120:in `perform'
  from -:30:in `<main>'

以下是我的设置：

的Gemfile

ruby '2.4.3'
gem 'activerecord4-redshift-adapter', '~> 0.2'
gem 'pg'

Ruby版

ruby 2.4.3p205 (2017-12-14 revision 61247) [x86_64-darwin17]

宝石清单

activerecord (4.2.10, 4.2.8)
activerecord4-redshift-adapter (0.2.1)
pg (1.0.0, 0.17.1)

脚本

require 'active_record'

conn = {
    adapter: 'redshift',
    database: '@database',
    host: '@host',
    port: 5439,
    username: '@username',
    password: '@password'
}

ActiveRecord::Base.establish_connection(conn)
sql = 'select count(*) from table'
ActiveRecord::Base.connection.execute(sql)

Answer 1

您使用的是pg gem版1.0.0，但它与您正在使用的active_record和activerecord4-redshift-adapter版本不兼容：

PGconn，PGresult和PGError常量已弃用，自版本1.0起将被删除。

这可以在pg gem的history中看到。

activerecord4-redshift-adapter uses both PGconn和PGError常量：

def connection_active?
  @connection.status == PGconn::CONNECTION_OK
rescue PGError
  false
end

虽然我无法完全复制您看到的错误消息，但通过修改Gemfile以使用较旧版本的pg gem，我能够更进一步：

gem 'pg', '~> 0.21'

我的确切步骤是：

创建Gemfile
创建包含您的Ruby代码的文件test.rb
运行bundle install
运行bundle exec ruby test.rb

这会产生以下错误：

/Users/test/.rvm/gems/ruby-2.4.3/gems/activerecord4-redshift-adapter-0.2.1/lib/active_record/connection_adapters/redshift_adapter.rb:568:in `initialize': could not translate host name "@host" to address: nodename nor servname provided, or not known (PG::ConnectionBad)

对于你遇到的问题，这几乎肯定是正确的方向，应该让你走上实现目标的道路。

无法加载＆＃39; active_record / connection_adapters / redshift_adapter＆＃39;

1 个答案: