Thread

Hi guys,

I hope this will help you.

Problem:
When adding a new entry with is_unique will work just fine but what about when you want to update the entry using the same form validation rule? is_unique will not work because it will detect that you are adding a duplicate entry. Which sucks, and you will be forced to create a new rule just for that.

Prerequisites:
1. when editing, you must pass the primary key as post data (which we mostly do)
Example where user_id is the primary key:

<input type="hidden" value="1" name="user_id" />

Benefits:
1. Same form validation rule for editing and adding

Code:

<?php  if ( ! defined('BASEPATH')) exit('No direct script access allowed');

class My_Form_validation extends CI_Form_validation {
 
 public function is_unique($str, $field)
 {
  list($table, $field)=explode('.', $field);
  $q = $this->CI->db->query("SHOW KEYS FROM $table WHERE Key_name = 'PRIMARY'")->row();
  $primary_key = $q->Column_name;
  
  if($this->CI->input->post($primary_key) > 0):
   $query = $this->CI->db->limit(1)->get_where($table, array($field => $str,$primary_key.' !='=>$this->CI->input->post($primary_key)));
  else:
   $query = $this->CI->db->limit(1)->get_where($table, array($field => $str));
  endif;
  
  return $query->num_rows() === 0;
    }
}


/* End of file My_Form_validation.php */
/* Location: ./application/libraries/My_Form_validation.php */

I’m solving that problem by copying rules (showed below) in my form_validation config:

// after setting post/create rules

$config['post/update'] = $config['post/create'];
$config['post/create'][0]['rules'] .= '|is_unique[post.title]';

that would probably solve it, if you have a lot of tables with is_unique rules.. you will be forced to copy and pasting each of it.

I like this approach!

I don’t have to maintain 2 rules, one for edit and one for insert.  The passive check should be pretty good but could lead to problems when the table contains composite keys.

Thanks for the code suggestion!

Hi, How can we set rules using this? I mean how can we pass the primary key to the rules? Can u please give me a sample usage on how to use this rule.Thanks 😊

the function only overrides that current is_unique method. that means you can use it the same way.

is_unique[users.username]

the primary key is automatically detected.

But as gte451f said, if you have Composite Primary Keys in your table, it wont work.

http://stackoverflow.com/questions/217945/can-i-have-multiple-primary-keys-in-a-single-table