1. Make sure that there are no duplicates!!!
   

   select distinct tc.COMPANY_ID, tc.NAME from 
          TAB_TACC_RECHNUNGEN tr,  
          tab_tacc_company tc 
   where tr.COMPANY_ID = tc.COMPANY_ID and 
          UPPER(tc.NAME) like UPPER('%scc%') 
   group by tc.COMPANY_ID, tc.NAME 
   order by tc.NAME
   
   

   tab_tacc_technungen is needed because we need only companies with invoices - but why join and not exist?
   Why distinct and group by?
   tc.company_id is PK of tab_tacc_company - so after elimination of 'join', distinct is not needed any more.
   
   

Just in case!

1. Ensure if it is false but not 'not True'
   

   if dict.has_key(companyId) == False:
   

   
   

List to String in Python

1. Using build in __str__ and str.strip
   

    if isinstance(tour_id, list):
               tour_id_str = str(tour_id).strip("[]")
   
   

   
   The fact is that tour_id contains only ints so 'casting' to string have to be done befor using str.join
   
   
2. Using for loop
   

   tmpCompanyListStr = ""
           for tmpCompany in cid:
               tmpCompanyListStr += "%s, " %(tmpCompany)
           tmpCompanyListStr = tmpCompanyListStr.rstrip(', ')
   

   It is hard to say if author had knowlage about str.join but he was using str.rstrip.