Magento direct SQL query returns NULL

Question

I am working on creating models for a module I'm developing but I've run into a problem echoing out the result from a query.

What I get when using a var_dump() calling the the model in the block is NULL

I don't understand because in the resource model, if i do an echo $select it prints out the query which I enter into phpMyAdmin and it find the row. I think i must be trying to output the row wrongly.

This is my resource model:

class MyCompany_Facebook_Model_Resource_Facebookcoupon extends Mage_Core_Model_Resource_Db_Abstract
{
    protected function _construct()
    {
        $this->_init('facebook/facebookcoupon', 'entity_id');
    }

    public function loadByField($field,$value)
    {
        $table = $this->getTable('facebook/facebookcoupon');
        $where = $this->_getReadAdapter()->quoteInto("$field = ?", $value);
        $select = $this->_getReadAdapter()->select()->from($table,array('facebook_id'))->where($where);
        $id = $this->_getReadAdapter()->fetchOne($select);
        return $id;     
    }

This is my model

class MyCompany_Facebook_Model_Facebookcoupon extends Mage_Core_Model_Abstract
{   

    protected function _construct()
    {
        parent::_construct();
        $this->_init('facebook/facebookcoupon');
    }

    public function loadByField($field,$value)
    {
        $id = $this->getResource()->loadByField($field,$value);
        $this->load($id);
    }
}

and i call it using this block

class MyCompany_Facebook_Block_Content extends Mage_Core_Block_Template
{
    private $couponCode;

    public function displayCoupon($test)
    {
        $facebookid = Mage::getModel('facebook/facebookcoupon')->loadByField('facebook_id', '14547854');

        var_dump($facebookid);

Answer 1

Adrock.use the below for more suitable solution

    $model = Mage::getModel('facebook/facebookcoupon') ->getCollection() 
->addFieldToFilter('facebook_id', 14547854) ->getFirstItem(); 

// here you'll get a collection but single record -

Please note:

    loadByField($field,$value) in resource model is wrong.you can use load() 
function only whenever,you will be trying to fetch data using primary key.