Switching from mysql to mysqli issues - php

Question

Below is some code that works fine, however it used mysql_* and i dont want that anymore. I have tried to redo this section in mysqli but it's not working. I can post my entire code if you wish, but i am certain i know where the issue lies. Below is the code:
Old:
public function verifyDatabase()
{
include('dbConfig.php');
$data = mysql_query("SELECT client_id FROM clients WHERE client_email_address = '{$this->_username}' AND client_password = '{$this->_pass_sha1}'");
if(mysql_num_rows($data))
{
list($this->_id) = #array_values(mysql_fetch_assoc($data));
return true;
}
else
{
return false;
}
}
New:
public function verifyDatabase()
{
include('dbConfig.php');
$data = $db->prepare("SELECT client_id FROM clients WHERE client_email_address = ? AND client_password = ? LIMIT 1");
$data->bind_param($this->_username, $this->_pass_sha1);
$data->execute();
$data->store_result();
if($data->num_rows)
{
list($this->_id) = #array_values($data->fetch());
return true;
}
else
{
return false;
}
}
I'm still learning mysqli and not quite ready for PDO stuff as i found that a little confusing. As i say, this whole script works perfectly with mysql_* but not so much with mysqli. When i try and log in my form doesnt display any errors nor does it push forward to the next page, so i know its this bit that is the issue

Answer 1

it is advised to use a helper function, either with old mysql or modern mysqli
public function verifyDatabase()
{
$sql = "SELECT client_id FROM clients WHERE email = ? AND password = ?";
return $this->db->getOne($sql ,$this->_username,$this->_pass_sha1);
}
Also note that dbConfig.php should not be included in the every method but, but only once. While DB handler should be assigned to a class variable in the constructor.

Answer 2

Change your code to this. I'm not saying it will fix problems but will be better.
public function verifyDatabase()
{
include('dbConfig.php');
$data = $db->prepare("SELECT client_id FROM clients WHERE client_email_address = ? AND client_password = ? LIMIT 1");
$data->bind_param($this->_username, $this->_pass_sha1);
$data->execute();
$data->store_result();
if($data->num_rows > 0)
{
$result = $data->fetch();
$this->_id = $result['client_id'];
return true;
}
else
{
return false;
}
}
You can also put var_dump($result); after the $result = $data->fetch(); line to print out what exactly is being returned.