php - Query to generate Excel Report Userwise -

i making report quiz application in codeigniter. there 3 tables tbl_users,tbl_answers , tbl_qbank.

tbl_users

t_id |  t_name  -------------- 

tbl_qbank

qid   |  ques  |  ans_1 |   ans_2   |  ans_3  | ans_4 |  correctans ---------------------------------------------------------------- 

tbl_answers

ans_id  |  user_id  |  q_id  |  ans_attempted --------------------------------------------- 

i want create report displays user information, correct answers , answer attempted him. using phpexcel

i have gotten of things done, need correct query not able figure out. getting answers tbl_answers, showing each row 1 one single user.

i can answers users dont know how them in single row.

i have tried following query

query -> returns answers user information single user

$this->db->select('*');     $this->db->from('tbl_users,tbl_qbank');     $this->db->where('tbl_users.t_id',$uid);     $this->db->where('tbl_qbank.qid=tbl_answers.q_id');     $this->db->join('tbl_answers','tbl_users.t_id = tbl_answers.user_id','left');     $query = $this->db->get();     if($query->num_rows()>0){         $results=$query->result_array();     }     return $results; 

what want show single row user name,questions skipped , questions answered candidates.