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Chapter 3
As result of our query, we should see a result set with three columns: product_id,
product_name, and product_sku. So, let's step back for a second in order to get
product names with SKUs. With raw SQL, we would have to write a five-line SQL
query, and we would only be retrieving two values from our products: from one
single EAV value table if we wanted to retrieve a numeric field, such as price, or
from a text value, such as product.
If we didn't have an ORM in place, maintaining Magento would be almost
impossible. Fortunately, we do have an ORM in place, and most likely, you will
never need to deal with raw SQL for working with Magento.
That said, let's see how can we retrieve the same product information by using the
Magento ORM:
1. Our first step is going to instantiate a product collection:
$collection = Mage::getModel('catalog/product')->getCollection();
2. Then, we will specifically tell Magento to select the name attribute:
$collection->addAttributeToSelect('name');
3. Now sort the collection by name:
$collection->setOrder('name', 'asc');
4. And, finally, we will tell Magento to load the collection:
$collection->load();
5. The end result is a collection of all products in the store sorted by name; we
can inspect the actual SQL query by running:
echo $collection->getSelect()->__toString();
With the help of only three lines of code, we are able to tell Magento to grab all the
products in the store to specifically select the name, and finally, order the products
by the name.
The last line, $collection->getSelect()->__toString(), allows
us to see the actual query that Magento is executing on our behalf.
The actual query being generated by Magento is:
SELECT `e`.*. IF( at_name.value_id >0, at_name.value, at_name_default.
value ) AS `name`
FROM `catalog_product_entity` AS `e`
LEFT JOIN `catalog_product_entity_varchar` AS `at_name_default` ON
(`at_name_default`.`entity_id` = `e`.`entity_id`)
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