diff --git a/lib/mastodon/cli_helper.rb b/lib/mastodon/cli_helper.rb
index ed22f44b2..aaee1fa91 100644
--- a/lib/mastodon/cli_helper.rb
+++ b/lib/mastodon/cli_helper.rb
@@ -25,7 +25,9 @@ module Mastodon
         exit(1)
       end
 
-      ActiveRecord::Base.configurations[Rails.env]['pool'] = options[:concurrency] + 1
+      db_config = ActiveRecord::Base.configurations[Rails.env].dup
+      db_config['pool'] = options[:concurrency] + 1
+      ActiveRecord::Base.establish_connection(db_config)
 
       progress  = create_progress_bar(scope.count)
       pool      = Concurrent::FixedThreadPool.new(options[:concurrency])