Update telephone numbers to 00

telephone-update.php

<?php

require_once('app/Mage.php');
umask(0);
Mage::app();

$db_conn = Mage::getSingleton('core/resource');
$r_conn = $db_conn->getConnection('core_read');
$w_conn = $db_conn->getConnection('core_write');
 
$sql = <<<"SQL"
	SELECT cv.value as `telephone`, e.* FROM customer_entity AS e
	LEFT JOIN customer_address_entity_varchar AS cv 
	ON ( cv.attribute_id = (
	SELECT attribute_id FROM eav_attribute 
	WHERE attribute_code = 'telephone'
	)
	AND cv.entity_id = e.entity_id)
	WHERE LENGTH(cv.value) <= 2
SQL;
$results = $r_conn->fetchAll($sql);

$x = 0;

foreach ($results as $result) {

	$update_sql = 'UPDATE customer_address_entity_varchar SET value = :new_value WHERE value_id = ' . $result['value_id'];

	try {

		$binds = array();
		$binds['new_value'] = '00';
		$w_conn->query($update_sql, $binds);

		echo '#' . $x . ' success - value_id: ' . $result['value_id'] . PHP_EOL;

	} catch (Exception $e) {

		echo '#' . $x . ' error - value_id: ' . $result['value_id'] . PHP_EOL;

	}

	$x = $x + 1;

}

echo 'Done!';

upload to magento root and run by sshing in and typing:

php telephone-update.php