I'm trying to build a simple form with drop-down lists to query my database (designed for a library for an afterschool program). The idea is that the drop-down lists are populated by the names of books or students, so that when you select a name and Submit, the database selects details with a matching foreign key from the table.
Problem is, whenever I open up the form, I get several copies of these lines above the form:
Notice: Undefined index: id in E:\XAMPP\htdocs\CMPS\Library\query\index.php on line 88
Notice: Undefined index: name in E:\XAMPP\htdocs\CMPS\Library\query\index.php on line 88
Notice: Undefined index: isbn in E:\XAMPP\htdocs\CMPS\Library\query\index.php on line 104
Notice: Undefined index: title in E:\XAMPP\htdocs\CMPS\Library\query\index.php on line 104
Likewise, each of the drop-down lists says either
Notice: Undefined index: name in E:\XAMPP\htdocs\CMPS\Library\query\searchform.html.php on line 20
or
Notice: Undefined index: title in E:\XAMPP\htdocs\CMPS\Library\query\searchform.html.php on line 30
index.php
<?php include_once
'../includes/helpers.inc.php';
require_once '../access.inc.php';
if (!userIsLoggedIn())
{
include '../login.html.php';
exit();
}
if (!userHasRole('Verified'))
{
$error = 'Only verified accounts may access this page.';
include '../accessdenied.html.php';
exit();
}
if (isset($_GET['action']) and $_GET['action'] == 'search')
{
include '../includes/db.inc.php';
$select = 'SELECT CONCAT_WS(\' \', student.First, student.Last) as Name, book.Title, checkout.Checked, checkout.Due';
$from = ' FROM checkout, student, book';
$where = ' WHERE student.ID = checkout.StudentID AND book.ISBN = checkout.BookISBN';
$placeholders = array();
if ($_GET['student'] != '')
{
$where .= " AND checkout.StudentID = :studentid";
$placeholders[':studentid'] = $_GET['student'];
}
if ($_GET['book'] != '')
{
$where .= " AND checkout.BookISBN = :bookisbn";
$placeholders[':bookisbn'] = $_GET['book'];
}
if (isset($_POST['ongoing']) && $_POST['ongoing'] == 'Yes')
{
$where .= " AND Ongoing = 1";
}
try
{
$sql = $select . $from . $where;
$s = $pdo->prepare($sql);
$s->execute($placeholders);
}
catch (PDOException $e)
{
$error = 'Error fetching checkouts.';
include 'error.html.php';
exit();
}
foreach ($s as $row)
{
$checkouts[] = array('Name' => $row['name'], 'book.Title' => $row['title'],
'Checked' => $row['checked'], 'Due' => $row['due']);
}
include 'query.html.php';
exit();
}
include '../includes/db.inc.php';
try
{
$result = $pdo->query('SELECT ID, CONCAT_WS(\' \', First, Last) as Name FROM student');
}
catch (PDOException $e)
{
$error = 'Error fetching students from database!';
include 'error.html.php';
exit();
}
foreach ($result as $row)
{
$students[] = array('ID' => $row['id'], 'Name' => $row['name']); #Line 88
}
try
{
$result = $pdo->query('SELECT ISBN, Title FROM book');
}
catch (PDOException $e)
{
$error = 'Error fetching books from database!';
include 'error.html.php';
exit();
}
foreach ($result as $row)
{
$books[] = array('ISBN' => $row['isbn'], 'Title' => $row['title']); #Line 104
}
include 'searchform.html.php';
searchform.html.php
<?php include_once
'../includes/helpers.inc.php'; ?>
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="utf-8">
<!-- <link href="../style.css" rel="stylesheet" media="screen"> -->
<title>Query Checkouts</title>
</head>
<body>
<h1>Query</h1>
<form action="" method="get">
<p>View checkouts satisfying the following criteria:</p>
<div>
<label for="student">By student:</label>
<select name="student" id="student">
<option value="">Any student</option>
<?php foreach ($students as $student): ?>
<option value="<?php htmlout($student['id']); ?>"><?php
htmlout($student['name']); ?></option> <!-- Line 20 -->
<?php endforeach; ?>
</select>
</div>
<div>
<label for="book">By book:</label>
<select name="book" id="book">
<option value="">Any book</option>
<?php foreach ($books as $book): ?>
<option value="<?php htmlout($book['isbn']); ?>"><?php
htmlout($book['title']); ?></option> <!-- Line 30 -->
<?php endforeach; ?>
</select>
</div>
<div>
<label for="ongoing">Ongoing only?:</label>
<input type="checkbox" name="ongoing" value="Yes" />
</div>
<div>
<input type="hidden" name="action" value="search">
<input type="submit" value="Search">
</div>
</form>
<p><a href="..">Return to PHL home</a></p>
<?php include '../logout.inc.html.php'; ?>
</body>
</html>
I tried checking the code, but phpcodechecker.com says there are zero errors, and I'm having a hard time using Chrome Logger to debug.
Hoping I can understand what I'm doing wrong so I won't make the mistake later in development!