How to check if email already exists in db with CodeIgniter - php

Question

I am doing application in CodeIgniter. I don't know how to compare email against db in CodeIgniter, please any one, help me.
Controller
public function signup()
{
$this->load->view('signup');
}
public function savedata(){
$this->load->library('form_validation');
$this->form_validation->set_rules('firstname', 'firstname', 'required');
$this->form_validation->set_rules('lastname', 'lastname', 'required');
if ($this->form_validation->run() == TRUE) // Only add new option if it is unique
{
$result = $this->account_model->insert();
if($result > 0)
{
$data['message'] = "Added successfully";
$this->load->view('signup',$data);
}
else
{
$this->index();
}
}
else
{
$this->load->view('signup');
}
}
How to check whether email already exists or not?

Answer 1

Suppose, you have user table and email column. So you have to add this line in form validation
$this->form_validation->set_rules('email','Email','required|valid_email|is_unique[users.email]');
Note
And need an unique index in your email column
check Documentation

Answer 2

Add a rule:
$this->form_validation->set_rules('email', 'Email', 'callback_rolekey_exists');
In the same Controller:
function rolekey_exists($key) {
$this->roles_model->mail_exists($key);
}
In Model,
function mail_exists($key)
{
$this->db->where('email',$key);
$query = $this->db->get('users');
if ($query->num_rows() > 0){
return true;
}
else{
return false;
}
}
Reference

Answer 3

Best Way
$this->form_validation->set_rules(
'email', 'Email', 'valid_email|required|is_unique[usr_user.user_email]',
array('is_unique' => 'This %s already exists.')
);

Answer 4

//in controller
public function usernameExist($username)
{
$user = $this->Model-> usernameExist($username);
if ($user) {
$this->form_validation->set_message(
'usernameExist',
'Username is already exist.'
);
return false;
} else {
return true;
}
}

Answer 5

function username_Exist($key)
{
$this->db->where('username', $key);
$query = $this->db->get('signup');
if ($query->num_rows() > 0) {
return true;
} else {
return false;
}
}
//type this in model

Answer 6

$this->form_validation->set_rules('username', 'User', 'trim|required|callback_username_Exist');
//type in controller in form validation