GROUP_CONCAT && left outer join on 1 table?
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I've got 1 table with Menu labels in it.I need with a query to get Parent label and UnderMenu label.when i execute this:

      SELECT es.Label MenuLabel, m.Label UnderLabel 
      FROM books_menu es
      LEFT JOIN books_menu m ON es.ID = m.MenuParentID 
      WHERE es.ParentID =1 
      AND m.Type='under'
      AND es.Type='main' 
      LIMIT 0 , 30

everything is OK but MenuLabel show on every record.Something like this:
      
      MenuLabel    UnderLabel
      Home         1
      Home         2
      Home         3
      Contacts     4

When i execute :

      SELECT es.Label MenuLabel, GROUP_CONCAT(m.Label) AS UnderLabel 
      FROM books_menu es
      LEFT JOIN books_menu m ON es.ID = m.MenuParentID 
      WHERE es.ParentID =1 
      AND m.Type='under'
      AND es.Type='main' 
      LIMIT 0 , 30

i get:

          MenuLabel    UnderLabel
           Home         1,2,3,4

How can i get this:

       MenuLabel    UnderLabel
       Home         1,2,3
       Contacts     4

Thank you:)