QQueryBuilder::SetVirtualNode PHP Method

    public function SetVirtualNode($strName, QQSubQueryNode $objNode)
    {
        $this->objVirtualNodeArray[trim(strtolower($strName))] = $objNode;
    }

 public function GetColumnAlias(QQueryBuilder $objBuilder, $blnExpandSelection = false, QQCondition $objJoinCondition = null)
 {
     if ($this->objSubQueryDefinition) {
         $objBuilder->SetVirtualNode($this->strName, $this->objSubQueryDefinition);
         return $this->objSubQueryDefinition->GetColumnAlias($objBuilder);
     } else {
         try {
             return $objBuilder->GetVirtualNode($this->strName)->GetColumnAlias($objBuilder);
         } catch (QCallerException $objExc) {
             $objExc->IncrementOffset();
             $objExc->IncrementOffset();
             throw $objExc;
         }
     }
 }