Question

I have a table where a filed contains roll numbers like so:

   id | roll_no
   --------------
   1  | 290320452
   2  | 290320453
   3  | 290340454
   4  | 290330455

from the above column I want roll_no with matching position 4 AND 5 with 32.
where the result would be

   id | roll_no
   --------------
   1  | 290320452
   2  | 290320453

For now I have done by filtering the result array like so:

    $subject_code = 32;    
    foreach($result as $row){
                    if($subject_code != NULL){
                        if(substr($row['roll_no'],3,2) == $subject_code){
                            $data[] = $row['roll_no'];
                        }
                    }
                    else{
                        $data[] = $row['roll_no'];
                    }
}

Is there a better way to filter while querying on mysql query.

I have seen SUBSTRING() function of mysql but no help.

Answer 1

select roll_no from your_table
where substring(cast(roll_no as char(11)), 4, 2) = '32'