How do I name a price from the datase utilizing ajax

I must name and show a price for the customers utilizing Ajax however I am undecided easy methods to do it.
Presently the plugin I take advantage of name it utilizing a question meaning the customers should refresh there browser each few seconds to see the brand new worth if it modified. Right here is the present code:

      `'`//newest highest/present value
        //$wdm_price_flag=false;
        /*$question = "SELECT MAX(bid) FROM " . $wpdb->prefix . "wdm_bidders WHERE auction_id =" 
        . $wdm_auction->ID;*/
        $desk = $wpdb->prefix . "wdm_bidders";
        $auctionid = $wdm_auction->ID;
        $question = $wpdb->put together("SELECT MAX(bid) FROM {$desk} WHERE 
        auction_id = %d", $auctionid);
        $curr_price = $wpdb->get_var($question);
        if (empty($curr_price)){
        $curr_price = get_post_meta($wdm_auction->ID, 'wdm_opening_bid', true);
            $no_bid = 1;
        }

I’ve learn different submit like this right here
and in addition strive to determine easy methods to do it from these pages and This One
However i am undecided easy methods to go about doing it that t will refresh robotically on a regular basis.