title: Subquery to join column's in same table?
body: <p>here this is my database structure :  # problem is to retrieval of pref_country</p>
  
  <pre><code>OrderLead :
   id   lead   order  time   #lead is foreign key to leaddeatail
   1    10     34     null
   2    14     34     null
   3    17     37     null
  
  leaddetail :                           # all pref_country foreign key to Country
   id   name  pref_country_1   pref_country_2   pref_country_3 
   4    rosh         3              4                   null
   10   amit         4              2                   3
   14   xxx          2             null                 null
  
  Country :
   id   name 
   2    India 
   3    USA 
   4    UK
  </code></pre>
  
  <p>now i want all information preferably by sub queries like:</p>
  
  <pre><code>orderleadid   lead_name    lead_pref_country  orderlead_time # where order = 34
  1             amit         Uk,India,USA       null
  2             xxx          India              null
  </code></pre>
  
  <p>i want query like(subquery) : # here for id and contry</p>
  
  <pre><code>SELECT id,(SELECT group_concat(P.country separator ",") from Country as P, leaddetail as LD where LD.id = orderlead.lead and LD.pref_contry_1 = P.id ) as pref country from orderlead where order = 34;
  </code></pre>