$(document).ready(function()
            {
                $("#display").change(function()
                {
                    var type = document.getElementById('display').value;
                    alert(type);
                    $.ajax(
                    {
                        //create an ajax request to load_page.php
                        type: "GET",
                        url: "DBOperations.php",
                        data : "type=" +type,
                        dataType: "json",  //expect text to be returned
                        success: function(response)
                        {
                            //$("#response").html(response);
                            //alert(response.);

                            $.each(response, function(index, element)
                            {
                                $('#response').html($(
                                {
                                    text: element.name
                                }));
                            });

                        },
                        error: function(jqXHR, textStatus, errorThrown)
                        {
                            alert('error: ' + textStatus + ': ' + errorThrown);
                        }

                    });
                });
            });

PHP:

try
                    {
                        $dsn = 'mysql:host=localhost;dbname=practice_db'; //your host and database name here.
                        $username = 'root';
                        $password = '';

                        //Connect to database
                        $conn = new PDO($dsn, $username, $password);
                        $query = "SELECT * FROM client WHERE client_type = :client_type";

                        //Prepare and Execute Query
                        $stmt = $conn->prepare($query);
                        $stmt->bindParam(':client_type', $type);
                        $stmt->execute();
                        //echo 'Here: ' .$stmt;
                        //$rows = $stmt->fetch();
                        $rows = $stmt->fetchAll();
                        foreach ($rows as $row)
                        {
                            echo "ClientID: ".$row['client_id'] . " ";
                            echo "Name: ".$row['client_name'] . " ";
                            echo "Title: ".$row['client_title'] . " ";
                            echo "Client Type: ".$row['client_type'] . "<br>";
                        }

                        //Display associative array
                        echo '<pre>';
                        print_r($rows) .'<br>';
                        header('Content-type: application/json');
                        json_encode($rows);
                        print_r(json_encode($rows));
                    }
                    catch (PDOException $ex)
                    {
                        echo "There was a problem executing the Query: " . $ex->getMessage();
                    }