Ruby Module to stream a SQL query to standard out, and yield each row to a block

database_query_streaming.rb

module DatabaseQueryStreaming

  def stream_query_rows(sql_query, options="WITH CSV HEADER")
    conn = ActiveRecord::Base.connection.raw_connection
    conn.copy_data "COPY (#{sql_query}) TO STDOUT #{options};" do
      while row = conn.get_copy_data
        yield row
      end
    end
  end

end