Issue on executing different query inside same Controller function - php

Question

Here I have function index which is having two different model calls as follows:
CONTROLLER:
function index()
{
$people = $this->M_results->search_people(); // first model method call
// print_r($people); //shows result
$skills = $this->M_results->get_skill($category_name); // second model method call
}
MODEL:
function search_people()
{
$this->db->select("registration,gender,profile_img,location");
$this->db->from('search_result');
$this->db->join('services','search_result.registration = services.reg_id','left');
$this->db->join('review','search_result.registration = review.reg_id AND review.active = 0','left');
$query = $this->db->get();
$result = $query->result_array();
return $result;
}
function get_skill($category_name)
{
$this->db->select('GROUP_CONCAT(skills.id ORDER BY skills.name ASC) as id,GROUP_CONCAT(skills.name ORDER BY skills.name ASC) as skill,sub_categories.name as sub_cat,class');
$this->db->from('skills');
$this->db->join('sub_categories','skills.sub_cat_id = sub_categories.id');
$this->db->join('categories','sub_categories.cat_id = categories.id');
$this->db->where('categories.name',$category_name);
$this->db->where('skills.active',0);
$this->db->group_by('sub_categories.name');
// echo $this->db->get_compiled_select(); exit();
$query = $this->db->get();
return $query->result();
}
Now the problem is that, the call to search_people is returning exact result.
But on running the second model call i.e to get_skill function, the select query of get_skill is including the columns of select query in search_result function. And shows the below database error:
Error Number: 1054
Unknown column 'registration' in 'field list'
SELECT registration, gender, profile_img, location,GROUP_CONCAT(skills.id ORDER BY skills.name ASC) as id, GROUP_CONCAT(skills.name ORDER BY skills.name ASC) as skill, sub_categories.name as sub_cat, class FROM skills JOIN sub_categories ON skills.sub_cat_id = sub_categories.id JOIN categories ON sub_categories.cat_id = categories.id WHERE categories.name = 'Child and Pet Care' AND skills.active =0 GROUP BY sub_categories.name
In the above query you can see both columns in search_people and get_skill.

Answer 1

Posting the answer for future references.
Resets the current Query Builder state. Useful when you want to build a query that can be cancelled under certain conditions.
$this->db->reset_query();
I found the solution from below link:
https://www.codeigniter.com/userguide3/database/query_builder.html#CI_DB_query_builder::reset_query