diff --git a/actioncable/test/subscription_adapter/postgresql_test.rb b/actioncable/test/subscription_adapter/postgresql_test.rb
index d262536d613..4348eb1b1ef 100644
--- a/actioncable/test/subscription_adapter/postgresql_test.rb
+++ b/actioncable/test/subscription_adapter/postgresql_test.rb
@@ -2,6 +2,7 @@
 
 require "test_helper"
 require_relative "common"
+require_relative "channel_prefix"
 
 require "active_record"