Lost connection to MySQL server during query: SHOW FIELDS FROM orders

rubyonrails-talk
1

I am getting an intermittent error, the one above. I have not gone into production, i am still in development. I seem to lose connection to the MySQL server. If I do a refresh it comes back and all is fine.

I have not been able to duplicate this. It simply occurs perhaps 1 out of ten times. Is this a characteristic of the development mode? I am using WEBrick. thanks, minka.

Here is the error: ActiveRecord::StatementInvalid in ProductsController#save_order Mysql::Error: Lost connection to MySQL server during query: SHOW FIELDS FROM orders

Here is a partial trace: RAILS_ROOT: script/../config/.. Application Trace | Framework Trace | Full Trace

/usr/local/lib/ruby/gems/1.8/gems/activerecord-1.14.4/lib/active_record/connection_adapters/abstract_adapter.rb:120:in `log' /usr/local/lib/ruby/gems/1.8/gems/activerecord-1.14.4/lib/active_record/connection_adapters/mysql_adapter.rb:184:in `execute' /usr/local/lib/ruby/gems/1.8/gems/activerecord-1.14.4/lib/active_record/connection_adapters/mysql_adapter.rb:292:in `columns' /usr/local/lib/ruby/gems/1.8/gems/activerecord-1.14.4/lib/active_record/base.rb:696:in `columns' /usr/local/lib/ruby/gems/1.8/gems/activerecord-1.14.4/lib/active_record/base.rb:1969:in `attributes_from_column_definition' /usr/local/lib/ruby/gems/1.8/gems/activerecord-1.14.4/lib/active_record/base.rb:1351:in `initialize_without_callbacks' /usr/local/lib/ruby/gems/1.8/gems/activerecord-1.14.4/lib/active_record/callbacks.rb:236:in `initialize' app/controllers/products_controller.rb:87:in `save_order' -e:4

2

It might be related to using the ruby mysql bindings instead of the native C bindings for your platform. Install the 'mysql' gem. It will build a native code extension callable from ruby which eliminates most mysql connection drops.

After installing the gem, make sure it is active by doing the following (swiped this from a post earlier this week!):

cremes$ irb irb(main):001:0> require 'rubygems' => true irb(main):002:0> require 'mysql' => false irb(main):003:0> puts Mysql::VERSION 20700 => nil

cr

3

If all else fails, try pre-loading your models if you are storing whole objects in the session. I was having what appeared to be intermittent db issues but the problem was the serialization of objects to the session.

class ApplicationController < ActionController::Base       model :order, :member, :cart end

Good luck, Chad