Adding OR and AND query condition to collection

// PRODUCT COLLECTION
$collection = Mage::getModel('catalog/product')->getCollection();
Adding AND query condition


Filtering collection to select only those products whose sku is like ‘ch’ AND status is equal to 1 (i.e. enabled status).


// AND QUERY
$collection->addAttributeToFilter('sku', array('like' => '%ch%'));
$collection->addAttributeToFilter('status', array('eq' => '1'));
Adding OR query condition


Filtering collection to select only those products whose sku is like ‘ch’ OR status is equal to 1 (i.e. enabled status).


// OR QUERY
$collection->addAttributeToFilter(array(
                array(
                    'attribute' => 'sku',
                    'like' => '%ch%'),
                array(
                    'attribute' => 'status',
                    'eq' => '1')
            ));
You may check the query statement with the following code


$collection->printLogQuery(true);

http://blog.chapagain.com.np/magento-adding-or-and-and-query-to-collection/