修改journals查询错误

app/models/mailer.rb

@@ -185,7 +185,7 @@ class Mailer < ActionMailer::Base
     # 查询user在课程及个人中留言
     @course_journal_messages = JournalsForMessage.find_by_sql("select DISTINCT jfm.* from journals_for_messages jfm, members m, courses c
      where m.user_id = '#{user.id}' and c.id = m.course_id and jfm.jour_id = c.id
-     and jfm.jour_type='Course' and (jfm.created_on between '#{date_from}' and '#{date_to}') order m.course_id, by created_on desc")
+     and jfm.jour_type='Course' and (jfm.created_on between '#{date_from}' and '#{date_to}') order by m.course_id,  created_on desc")
 
     @user_journal_messages = user.journals_for_messages.where("jour_type='Principal' and (created_on between '#{date_from}' and '#{date_to}')").order('created_on DESC')