如何在Magento中禁用SQL Query echo

Question

I have create module for testing in Magento and i call change action url from browser and there SQL query for catalog/product is printed.

I user this code

<?php
class Test_Demo_IndexController extends Mage_Core_Controller_Front_Action
{

public function indexAction()
{
$this->loadLayout();     
$block = $this->getLayout()->createBlock('capacityweb/Test','Test',array('template' => 'capacity/web/test.phtml'));
$this->getLayout()->getBlock('content')->append($block);
$this->renderLayout();
}

public function changeAction()
{
$this->loadLayout();     
$this->renderLayout();

$action=$this->getRequest()->getParam('action');        
$id=$this->getRequest()->getParam('id');


if($action!=null && $id!=null)
{
$relContact = Mage::getModel('catalog/product')->getCollection()->load($id);   
}


}

} 

if i use

$relContact = Mage::getModel('catalog/product')->getCollection()->load($id);

then magento display SQL query but instead of this

i use

$relContact = Mage::getModel('catalog/product')->getCollection();   

then magento not display anything.

So how to fix issue with

$relContact = Mage::getModel('catalog/product')->getCollection()->load($id);   

Answer 1

This is not an issue.
Magento uses the Lazy Loading design pattern for collections.
The sql for a collection is not executed until the collection is loaded or until you iterate through the results.
So Mage::getModel('catalog/product')->getCollection() will return an object that is an instance of Mage_Catalog_Model_Resource_Product_Collection that you can use how you need, but you don't have the products yet.
When calling Mage::getModel('catalog/product')->getCollection()->load() (by the way...the $id parameter is useless), then the query SELECT FROM catalog_product_entity..... is exectuted and in $collection->getIterator() you will have the records from the database as instances of Mage_Catalog_Model_Product.
[EDIT]
If you want a single product skip the getCollection call. You can get the instance of a product like this

$product = Mage::getModel('catalog/product')->load($id);
//changes some attributes
$product->setData('description', $description);
//or
//$product->setDescription($description);
$product->save().

See more details about it here.