如何从插入的行中获取最后一个id？

Question

I'm trying to get the ID of my master table to be inserted to my transaction table. The insert is happening inside a loop.

Behavior:

• Insert master
• Get id
• Insert Transaction
• Insert Master
• Get id
• Insert Transaction

Controller:

 //Insert Master
 foreach($arr_master as $res_master){

    /*$data['ID_REQUIREMENT_TRANS'] this is an auto-increment column. Inserted automatically*/

    $data['ID_REQUIREMENT']     = $res_master;
    $data['SENT_BY_DATE']       = date("Y-m-d H:i:s");                                                             
    $data['STATUS']             = 1;            

    $this->MAdmin->ins_assign_pic($data);

        //Insert Trans
        foreach($arr_trans as $res_trans){


            $data_d['ID_REQUIREMENT_TRANS'] = $id; //Need to get the last inserted id of the master table               
            $data_d['RECEIVED_BY']              = $res_trans; 
            $data_d['RECEIVED_BY_DATE']     = NULL; 
            $data_d['STATUS']                   = 1;            

            $this->MAdmin->ins_assign_pic_d($data_d);
        }
    }

Model:

function ins_assign_pic($data){
    $q_ins_assign_pic   = $this->db->insert('pm_requirement_assign_pic',$data);
    return $q_ins_assign_pic;

    $id = $this->db->insert_id(); 
    return $id;      //How to send this to my controller
    return true;
}

function ins_assign_pic_d($data_d){
    $q_ins_assign_pic_d = $this->db->insert('pm_requirement_assign_pic_d',$data_d);

    return $q_ins_assign_pic_d;
}

Answer 1

Try controller

$id = $this->MAdmin->ins_assign_pic($data);

And model

function ins_assign_pic($data){
    $q_ins_assign_pic   = $this->db->insert('pm_requirement_assign_pic',$data);
    //return $q_ins_assign_pic;

    $id = $this->db->insert_id(); 
    return $id;      //How to send this to my controller
   // return true;
}