code: def getColumnName(self, attribute):
          
          if attribute not in self.attrToColumnNameCache:
              self.attrToColumnNameCache[attribute] = '.'.join(
                  (self.getTableName(attribute.type),
                   self.getShortColumnName(attribute)))
          return self.attrToColumnNameCache[attribute]
docs: Retreive the fully qualified column name for a particular
          attribute in this store.  The attribute must be bound to an
          Item subclass (its type must be valid). If the underlying
          table does not exist in the database, it will be created as a
          side-effect.
  
          @param tableClass: an Item subclass
  
          @return: a string