1 files changed, 5 insertions, 0 deletions
diff --git a/activerecord/lib/active_record/connection_adapters/mysql_adapter.rb b/activerecord/lib/active_record/connection_adapters/mysql_adapter.rb
index 20028ffcfd..9c55c51f46 100755
--- a/activerecord/lib/active_record/connection_adapters/mysql_adapter.rb
+++ b/activerecord/lib/active_record/connection_adapters/mysql_adapter.rb
@@ -49,6 +49,11 @@ module ActiveRecord
         rescue LoadError => cannot_require_mysql
           # Use the bundled Ruby/MySQL driver if no driver is already in place
           begin
+            ActiveRecord::Base.logger.info(
+              "WARNING: You're using the Ruby-based MySQL library that ships with Rails. This library is not suited for production. " +
+              "Please install the C-based MySQL library instead (gem install mysql)."
+            ) if ActiveRecord::Base.logger
+
             require 'active_record/vendor/mysql'
           rescue LoadError
             raise cannot_require_mysql