Why am I getting a PG error on heroku when it works fine on my local rails environment?

I am getting the following error:

ReportsController#return_search (ActiveRecord::StatementInvalid) "PGError: ERROR: syntax error at or near \"FROM\"\nLINE 5: ...OUNT(contact_postalcards.id) AS postalcard_count, FROM \"cont...\n 

It works fine locally, but when I push to heroku I get the error:

What do I need to change so it will work also on Postgres on Heroku?

@list = Contact.find :all,
  :select => "companies.name AS co_name, 
             companies.id AS comp_id, 
              COUNT(contact_emails.id) AS email_count, 
          开发者_如何学JAVA    COUNT(contact_calls.id) AS call_count, 
              COUNT(contact_letters.id) AS letter_count, 
              COUNT(contact_postalcards.id) AS postalcard_count",

  :conditions => ['contact_emails.date_sent < ? and contact_emails.date_sent > ?', 
                  report_end_date, report_start_date],

  :joins => [
    "LEFT JOIN companies ON companies.id = contacts.company_id",
    "LEFT JOIN contact_emails ON contact_emails.contact_id = contacts.id",
    "LEFT JOIN contact_letters ON contact_letters.contact_id = contacts.id",
    "LEFT JOIN contact_postalcards ON contact_postalcards.contact_id = contacts.id",
    "LEFT JOIN contact_calls ON contact_calls.contact_id = contacts.id"
  ],
  #:group => "companies.id"
   :group => "companies.name"
puts @list[0].attributes.inspect

From the errormessage:

AS postalcard_count, FROM

Drop this comma , in your query, it's your bug.

It looks like this was a PG specific so I changed the database structure altogether.