<?php

class ExQuote extends DataObjectDecorator {
   
function TotalWeight()
{

$sqlQuery = new SQLQuery(
    "SUM(Recipe.Weight)", // Select
    "Recipe", // From
       "Recipe.QuoteID =" . $this->Owner->ID //Where
      
       );
   
    $totalWeight = $sqlQuery->execute()->value();

return $totalWeight;

}
      public function updateCMSFields(FieldSet &$fields){
      
      
      $fields->addFieldToTab("Root.Checks", new LiteralField ( '','Total Weight'));
      $fields->addFieldToTab("Root.Checks", new LiteralField ('', $this->TotalWeight()));

   }
   
}