Почему код грузит mysql?

$querystring = "SELECT * FROM `sites` WHERE `hostname` LIKE '%$search%' OR `url` LIKE '%$search%'";
		
		$accounts = explode(', ', $accounts);
		
		for ($i = 0; $i <= count($accounts) - 1; $i++) {
			$account_id = (int) mysqli_query($connect, "SELECT `account_id` FROM `accounts` WHERE `login` = '".$accounts[$i]."'")->fetch_array(MYSQLI_NUM)[0];
			if ($i = 0) {
				$querystring .= "AND WHERE `account_id` = '".$account_id."' ";
			}
			else {
				$querystring .= 'OR `account_id` = '.$account_id;
			}
		}
		$querystring .= 'ORDER BY `insearch` DESC';