Joomla query Object (stdClass) with random

Question

I'm building a Joomla template. For this I need to test/query two fields in the DB. I'm trying to get familiar with getDBO class but stuck here.

These two queries do nearly the same. I need both variables $category and $hasField . How can merge these two queries into one? This is a bit redundant.

$db = JFactory::getDBO(); 
$id = JRequest::getInt('id'); 

$db->setQuery('
   SELECT 
       #__categories.title 
   FROM 
       #__content, 
       #__categories 
   WHERE 
       #__content.catid = #__categories.id 
   AND 
       #__content.id = '.$id
    ); 
$category = $db->loadResult();


$db->setQuery('
   SELECT 
        #__attachments.filename,
        #__attachments.parent_id 
    FROM 
        #__attachments 
    WHERE 
        #__attachments.parent_id =' . $id
    ); 
$hasField = $db->loadResult();

Answer 1

You can try joining #__attachments to the 1st query.

SELECT 
   #__categories.title,
   #__attachments.filename,
   #__attachments.parent_id 
FROM 
   #__content, 
   #__categories,
   #__attachments 
WHERE 
   #__content.catid = #__categories.id 
AND
   #__attachments.parent_id = #__content.id
AND 
   #__content.id = $id

Answer 2

I might be wrong there as no place to test but it suppose to be like left joined:

SELECT 
   #__categories.title, atch.filename
 FROM 
   #__content, 
   #__categories
 LEFT JOIN
   #__attachments AS atch ON atch.parent_id = #__content.id 
 WHERE 
   #__content.catid = #__categories.id 
 AND 
   #__content.id = '.$id
);