Ruby on rails 如何在ruby中编写SQL查询分组？

帮助我在ruby中按条件编写GROUP_。我现在不得不将PHP项目迁移到Ruby，并且面临这个问题。不要严格评判，我是Ruby新手

这是php中的查询：

$get_details_email = db_query("Select secret_key,trustee_status,email_id from trustees where request_by='email' AND user_id='$user_id' group by email_id");

如何将下面的查询按电子邮件\u id分组

get_details_email = Trustee.select(:secret_key, :trustee_status, :email_id).where(:request_by => 'email', :user_id => user_id)

get_details_email = Trustee.select(:secret_key, :trustee_status, :email_id).where(:request_by => 'email', :user_id => user_id).group(:email_id)