Check if two column match on SQL PHP - php

Question

I have a form where the user has to enter their reservation id and last name. If these two values match in the database then I need to return the corresponding values from the database.
I have two files, one that is html where I use ajax and one php file. When clicking on the button, nothing is being returned, I am not seeing any specific errors and I am sure that the value I put in are correct.
<script>
var ajax = getHTTPObject();
function getHTTPObject()
{
var xmlhttp;
if (window.XMLHttpRequest) {
// code for IE7+, Firefox, Chrome, Opera, Safari
xmlhttp=new XMLHttpRequest();
} else if (window.ActiveXObject) {
// code for IE6, IE5
xmlhttp=new ActiveXObject("Microsoft.XMLHTTP");
} else {
//alert("Your browser does not support XMLHTTP!");
}
return xmlhttp;
}
function updateCityState()
{
if (ajax)
{
var reservation_id = document.getElementById("reservation_id").value;
var guest_last_name = document.getElementById("guest_last_name").value;
if(reservation_id)
{
var param = "?reservation_id=" + reservation_id + "&guest_last_name=" + guest_last_name;
var url = "test04.php";
ajax.open("GET", url + param, true);
ajax.onreadystatechange = handleAjax;
ajax.send(null);
}
}
}
function handleAjax()
{
if (ajax.readyState == 4)
{
var guest_full_name = document.getElementById('guest_full_name');
var unit_number = document.getElementById('unit_number');
var floor = document.getElementById('floor');
var key_sa = document.getElementById('key_sa');
if(!!ajax.responseText) {
var result = JSON.parse(ajax.responseText);
if(!!result){
guest_full_name.innerHTML = (!!result.guest_full_name) ? result.guest_full_name : '';
unit_number.innerHTML = (!!result.unit_number) ? result.unit_number : '';
floor.innerHTML = (!!result.floor) ? result.floor : '';
key_sa.innerHTML = (!!result.key_sa) ? result.key_sa : '';
}
}
}
}
</script>
<p id='employee_name'></p>
<p id='employee_age'></p>
<p id='safe_code'></p>
My test04.php
<?php
$conn = mysqli_connect("","","","");
$reservation_id = mysqli_real_escape_string($conn, $_GET['reservation_id']);
$guest_last_name = mysqli_real_escape_string($conn, $_GET['guest_last_name']);
$query = "SELECT reservation_id, guest_full_name, guest_last_name unit_number, floor, key_sa FROM reservations2 INNER JOIN guest ON (reservations2.reservation_id=guest.reservation_idg) INNER JOIN unit USING (unit_id) where reservation_id ='".$reservation_id."'AND guest_last_name ='".$guest_last_name."";
$result = mysqli_query($conn, $query) or die(mysql_error());
$response = array();
if(mysqli_num_rows($result) > 0) {
while($row = mysqli_fetch_assoc($result)) {
$response['guest_full_name'] = ($row['guest_full_name'] != '') ? $row['guest_full_name'] : '';
$response['unit_number'] = ($row['unit_number'] != '') ? $row['unit_number'] : '';
$response['floor'] = ($row['floor'] != '') ? $row['floor'] : '';
$response['key_sa'] = ($row['key_sa'] != '') ? $row['key_sa'] : '';
}
}
echo json_encode($response, true);
?>

Answer 1

I am not seeing any specific errors
Where are you looking?
Did you check the raw response from the PHP script or just look at what was rendered in your browser?
Did you verify that error logging is working and did you check your logs?
The logic of your PHP is unclear - your JSON data and the PHP array can't handle multiple records yet you process multiple records. It would be nice to implement REST properly. This should also apply authentication and use CSRF for security - but I'll assume you left those out for illustrative purposes.
Your code is not written to handle failures or missing data. Consider (noting all the differences with what you posted):
<?php
$conn = mysqli_connect("","","","");
$response = array();
$reservation_id = mysqli_real_escape_string($conn, $_GET['reservation_id']);
$guest_last_name = mysqli_real_escape_string($conn, $_GET['guest_last_name']);
$query = "SELECT reservation_id, guest_full_name
, guest_last_name unit_number, floor, key_sa
FROM reservations2
INNER JOIN guest
ON (reservations2.reservation_id=guest.reservation_idg)
INNER JOIN unit USING (unit_id)
WHERE reservation_id ='".$reservation_id."'
AND guest_last_name ='".$guest_last_name."";
$result = mysqli_query($conn, $query);
if (!$result) {
$response['status']=503
$response['msg']="Error";
trigger_error(mysql_error());
finish($response);
exit;
}
$response['status']=200;
$response['msg']='OK';
$response['guest_full_name'] = htmlentities($_GET['guest_last_name']);
$response['reservations']=array();
while($row = mysqli_fetch_assoc($result)) {
$response['reservations'][]=array(
'unit_number'=>$row['unit_number'],
'floor'=>$row['floor'],
'key_sa'=>$row['floor_sa']);
}
}
finish($response);
exit;
function finish($response)
{
header("HTTP/1.1 $response[status] $response[msg]");
header("Content-type: application/json");
echo json_encode($response, true);
}