AsyncRecord¶ ↑

One of the greatest things about running on an event-based server is that you can get accelerated performance in database access.

Usually there is a lot of time spent blocking for a database query to return. In AsyncRecord, your queries don’t block the request. You will receive a callback once the query has completed. This has major performance implications.

NOTE: Even though your connections are non-blocking to the database server, the database server is still blocking when accessing IO (disk/memory).

To use AsyncRecord, do the following:

Install the Gem:

sudo gem install async_record

Setup async_record:

require 'async_record'
conn = AsyncRecord::Connection::MySQL.new(:host => "127.0.0.1", :port => 3306, :user => "root", :database => "database")
conn.connect

Define a model:

class User < AsyncRecord::Base
  set_table_name "users"
end

These examples are for the Fastr web framework.

In your controller, try the following (remember to put the following in a deferred response):

User.all(:limit => 256) do |users|
  users.each do |user|
    response.send_data("#{user.username}\n")
  end
  response.succeed
end

User.find(1) do |user|
  if user.nil?
    response.send_data("User not found")
  else
    response.send_data("User: #{user.username}\n")
  end
  response.succeed
end

User.count do |count|
  response.send_data("Count: #{count}")
  response.succeed
end

User.query("select username from users") do |results|
  response.send_data("Results: #{results.inspect}")
  response.succeed
end

WARNING: AsyncRecord is under heavy development, but its pretty cool :).