Optimising codeigniter query, Join or Where

Question

I am relatively new to CI, I read that using join may slow down reporting, In my database there will be more than 100k records. I have written these two queries in CI but havent noticed much difference. I want to know if I am writing these queries appropriately or if there is a better way to get such query, unfortunately I do not know how to post these in a sample fiddle like structure.

function select_data_specific_customer($from, $to, $customer, $threshold = '') {

        //die($from);
        $currentuserid = $this->session->userdata('userid');
        $this->db->select('timestamp');
        $this->db->select('count');
        $this->db->select('price');
        $this->db->select('totalPrice');
        $this->db->select('reference');
        $this->db->select('customers_r');
        $this->db->select('userID_r');
        $this->db->from('logger');
        $this->db->from('users_customer');
        $this->db->where(array('users_customer.custo_id' => "logger.customers"), NULL, FALSE);      
        //users_customer contains connection between users and customers (  id  userID  custo_id    checked )
        $this->db->where(array('users_customer.userID' => $currentuserid), NULL, FALSE);
        $this->db->where(array('users_customer.checked' => '1'), NULL, FALSE);
        $this->db->where('cast(timestamp as date) BETWEEN "' . date('Y-m-d', strtotime(str_replace('-', '/', $from))) . '" and "' . date('Y-m-d', strtotime(str_replace('-', '/', $to))) . '"');


        $query = $this->db->get();

        if ($query->num_rows() > 0) {
            foreach ($query->result() as $row) {
                $data[] = $row;
            }

            return $data;
        }

        return false;
    }

This is the second function

function select_data_specific_customer($from, $to, $customer, $threshold = '') {

        //die($from);
        $currentuserid = $this->session->userdata('userid');
         $this->db->select('timestamp');
        $this->db->select('count');
        $this->db->select('price');
        $this->db->select('totalPrice');
        $this->db->select('reference');
        $this->db->select('customers_r');
        $this->db->select('userID_r');
        $this->db->from('logger');
        $this->db->join("users_customer", "users_customer.custo_id=logger.customers", 'inner');
        $this->db->where(array('users_customer.userID' => $currentuserid), NULL, FALSE);
        $this->db->where(array('users_customer.checked' => '1'), NULL, FALSE);
        $this->db->where('cast(timestamp as date) BETWEEN "' . date('Y-m-d', strtotime(str_replace('-', '/', $from))) . '" and "' . date('Y-m-d', strtotime(str_replace('-', '/', $to))) . '"');


        $query = $this->db->get();

        if ($query->num_rows() > 0) {
            foreach ($query->result() as $row) {
                $data[] = $row;
            }

            return $data;
        }

        return false;
    }

I wish to know if there is a more optimal way to write the same query, because at this moment both function is taking about 6 second to display. The result can grow to more than 200k later and the time might increase to display it.

Any help will be appreciated.

Answer 1

return $this->db->query("your query here");

did you try query above, and use * to select