Magento update multiple attribute product cases

magento19_attributes_updates.php

// Case 1

$product=Mage::getModel('catalog/product')->load($id);
$product->setSpecialFromDate('2010-10-28');
// below code use for time format 
$product->setSpecialFromDateIsFormated(true);
$product->getResource()->saveAttribute($product, 'special_from_date');

// Using Product Collection:

$productIds = array(1,3,2);
$products = Mage::getModel('catalog/product')->getCollection()
->addAttributeToFilter('entity_id', array('in' => $productIds));

foreach($products as $product)
{
    $product->setSpecialFromDate('2010-10-28');
    // below code use for time format 
    $product->setSpecialFromDateIsFormated(true);
    $product->getResource()->saveAttribute($product, 'special_from_date');
}


// - No reindex event registered
// - Probably no store management
// - Only one product each time (commit transaction every time)

// Case 2

Mage::getSingleton('catalog/resource_product_action')->updateAttributes($allPro‌​ductIds, $attrData, $storeId);

// - Multimple attributes
// - Store management
// - No reindex event registered


// Case 3

Mage::getSingleton('catalog/product_action')->updateAttributes($allPro‌​ductIds, $attrData, $storeId);

// - Same as case 2 + register mass action indexer event

// TIP: To reindex a sinble product:

$product = Mage::getModel('catalog/product')->load('29412'); // Product Id
$event = Mage::getSingleton('index/indexer')->logEvent(
        $product,
        $product->getResource()->getType(),
        Mage_Index_Model_Event::TYPE_SAVE,
        false
    );
Mage::getSingleton('index/indexer')
    ->getProcessByCode('catalog_product_flat') // Adjust the indexer process code as needed
    ->setMode(Mage_Index_Model_Process::MODE_REAL_TIME)
    ->processEvent($event);