Bug in PHP code - php

Question

Am working on a student portal, below is the code i used for students position but, every user keeps getting 1st position. Every student seems to have 1st position, when they check their results from the front view. Cant seem to figure out where the problem is from in the code
function get_position($student, $class, $session, $term){
$this->db->select('*');
$this->db->from('result');
$this->db->where(array( 'class_id'=>$class, 'Session'=>$session, 'Term'=>$term));
$this->db->order_by('Total', 'asc');
$other_results = $this->db->get()->result_array();
$this->db->select("*");
$this->db->from('result');
$this->db->where(array('class_id'=> $class, 'Session'=>$session, 'Term'=>$term, 'StudentID'=>$student ));
$student_result = $this->db->get()->result_array();
$student_total = $this->get_student_total($student_result);
$position =1;
foreach($other_results as $res){
if($student_total < $res['Total']){
$position++;
}
}
return $position;
}
function get_student_total($result){
$total = 0;
foreach($result as $res){
$total+= $res['Total'];
}
return $total;
}
}
?>

Answer 1

I am assuming that the result table may have many records for a given studentID. Several test scores (Totals) for each student during the term right?
This should do the trick
public function get_position($student, $class, $session, $term)
{
//I like to use db method chaining.
$ranking = $this->db->select('StudentID')
->select_sum('Total', 'sumScore')
->from('result')
->where(array('class_id' => $class, 'Session' => $session, 'Term' => $term))
->group_by('StudentID')
->order_by('sumScore', 'desc')
->get()->result_array();
//The code above retrieves results from a query statement that looks like this:
//SELECT `StudentID`, SUM(`Total`) as sumScore
//FROM `result` where `class_id` = $class and `Session` = $session and `Term` = $term
//GROUP BY `StudentID`
//order by `sumScore` desc
$position = 1;
foreach($ranking as $rank)
{
if($rank['StudentID'] !== $student)
{
++$position;
}
else
{
return $position;
}
}
return NULL; //to indicate studentID was not found
}