Magento – Fetch Value from Collection Without Foreach Loop

collection-filteringcollection;performance

I have a custom collection

$someCollection = Mage::getModel('mymodule/mymodel')->getCollection()
                           ->addFieldToSelect('some_field')
                           ->addFieldToFilter('another_field', array('eq' => $someValue));

Now consider, that this collection will always return only one row from the table, i.e.

$someCollection->getSize();

will always be "1". How to get the value of "some_field" without a foreach like:

foreach($someCollection as $row){
    $catchTheValue = $row->getSomeField();
}

I don't want to write foreach loop for one iteration. Can someone help?

Best Answer

If you know that the collection just has one item then you could simply use $someCollection->getFirstItem(). This will give you the first and in your case only item. You can then continue to use the getSomeField() etc on this object.

A second option is possible to use ->load($attribute_value, 'attribute_code'); on the object but this can add overhead if the table is of a large size.

Related Solutions

Catalog Search – addFieldToFilter with Like Removing Characters in Query

It appears that the problem is when adding attributes to filter the Zend_DbAdapter quoteInto strips out the ?.

I would suggest using an sql wildcard for a single character _ instead of the ?. This will not match exactly ? but will instead match any single character. Note that this could return false results as the two urls that follow would both match:

http://localhost/magento/index.php/electronics/cameras.html?cat=25&price=-100
http://localhost/magento/index.php/electronics/cameras.html*cat=25&price=-100

Have a look at Alan Storm's answer for a bit more detail on the problem: https://stackoverflow.com/questions/3555932/magento-loadbyattribute-fails-on-question-marks

Magento – Bad performance looping through all products

Product Collection from Category

// Step 1
$category = Mage::getModel('catalog/category')->load($category_id);

// Step 2
$productCollection = Mage::getModel('catalog/product')->getCollection();

// Step 3
$productCollection->addCategoryFilter($category);

// Step 4
$productCollection
    ->addAttributeToSelect('sku')
    ->addAttributeToSelect('another_attribute')
    ->addAttributeToFilter('type_id', 'simple')
    ->addAttributeToFilter('status', 1);

// Now you can loop through your collection
foreach($productCollection as $product) {
    $product->getSku();
    $product->getAnotherAttribute();
    // and so on...
}

So what's going on?

We loaded a category model. We will use that in the product collection.
We instantiated the product collection model.
We added the category for filtering.
We added the appropriate attributes for selection and filtering.

NOTE: Do not use the asterisk unless you plan on using every attribute being returned. Just like you shouldn't use the asterisk in a MySQL query unless you plan on getting everything from that table.

Once I have all my attributes and filters in place, I can loop through my collection. I do not need to call the load() method because lazy loading does that for me.

Once I'm in the loop, I have access to the product object Mage_Catalog_Model_Product. I do not need to instantiate another model inside the loop. The collection does this for me.