Errata

In the supplied css you are inconsistent in referencing images. In some cases you use '/phpmm/images...' and in other places '../images'. The latter format is much better since it does not depend on the name given to the root directory. In my case I am using a wamp server on my PC and the first format simply does not work.

Missing a semicolon here:


if($result) {
echo "<p>Your query was processed successfully.</p>" <Missing semicolon here>
echo "<p>{$query_text}</p>";

}

In the code on this page, the 4th line from the bottom reads

echo "<p>Your query was processed successfully.</p>"

Without the trailing semi-colon (;), the code breaks. The line should read,

echo "<p>Your query was processed successfully.</p>";

(Note the semi-colon at the end.

The error is in this section. The author writes

"But it gets worse! You're dealing with real humans, and humans do funny things. Suppose someone enters this SQL into your form:

CREATE TABLE urls (
id int,
url varchar(100),
description varchar(100)
);

Now you've got a new problem: this isn't a SELECT, but your search code won't find one of those special words at the the beginning. The first character is a space: " "... "


In these paragraphs, the author attempts to make a point about how white space could potentially kill your effort to locate SQL keywords CREATE, INSERT, UPDATE, DELETE, & DROP at the first character position. However, no one can see there is a problem with that query statement because all white space disappears in printed books. I am sure error was easy for the author to spot on screen, however, it's not visible to the reader in print.

There is a HTML error in the code segment. There is an open <span> tag.
The error is in the following code segment:

<div id="content">
<h1>We're really sorry...</h1>
<p><img src="../images/error.jpg" class="error" />
<?php echo $error_message; ?>
<span></p>
...
</div>

The code segment should be (that is if it is the intention of the author to emphasize the error using CSS, and mirror it the way it is displayed in Figure 7-5):

<div id="content">
<h1>We're really sorry...</h1>
<p>
<img src="../images/error.jpg" class="error" />
Apparently, <span><?php echo $error_message; ?></span>
</p>
...
</div>

isset function always reads as true and therefore will never print "something went wrong, and that's how you ended up here". Maybe the preg_replace 'sets' it to an empty value?

Using the empty() function like this seems to fix it:
<?php
$error_message = preg_replace("/\\\\/", '', $_REQUEST['error_message']);
if (empty($error_message)) {
$error_message = "Something wen't wrong, and that's how you ended up here!";
}
?>

"... create a small script called display_error.php, and type this code:"

<?php

echo "Hello, {$first_name}\n\n";
$query = "SELECT * FROM users WHERE first_name = {$first_name}";
echo "{$query}\n\n";

?>

The question here is ..... in which directory should this little script be created. Because
on page 210, the code now has a new require instruction see code below:

<?php

require '../scripts/app_config.php';

echo "Hello, {$first_name}\n\n";
$query = "SELECT * FROM users WHERE first_name = {$first_name}";
echo "{$query}\n\n";

?>

Because the author never made clear where create display_error.php, this require instruction could potentially cause any error (by pointing to a file that may or may not exist).

user_profile_pic should be user_pic_path

I suspect there is a typo in the PHP code where a call to PHP function header is made. The second and third line line should both be preceded by a quote character. Currently, the code tries to concatenate non-strings.

catch phrase missing $
Should read } catch (Exception $exc) {

Since the email address is inserted into a link, I believe the email address should be preceded by "mailto:", like so:

<a href="<?php echo 'mailto:' . $email; ?>">

The author warns of the dangers of copy and paste, yet it would appear that his code examples suffer from a copy/paste mistake.

The code at the top of the page creates a function, and is as follows:

function display_message ($msg, $msg_type) {
echo " <div class='{#msg_type}'>\n";
echo " <p>{$msg</p>\n";
echo " </div>\n";
}

The typo is in line two: #msg_type was used rather than $msg_type. This typo was repeated a second time (the copy/paste pitfall) further down the page.

The example code is repeated on the next page (337) and in the consolidated example, the correct $msg_type convention is printed.

in the book, (and FILES)

it reads:

define(VALiD_USERNAME, "admin");
define(VALiD_PASSWORD, "super_secret");

Which for me kept throwing up "undefined constant errors"

It should read:

define("VALID_USERNAME", "admin");
define("VALID_PASSWORD", "super_secret");

there needs to be quotation marks around "VALID_USERNAME" and "VALID_PASSWORD"

The comment "// Log out on browser close" seems to be incorrect.

Sessions uses Cookies to store and return the current SessionID when a page issues the session_start(); call. There is no mention of what happens if the user's browser rejects the setting request for the cookie or does not return it for any reason (such as cookies being turned off or cookie monitoring with permission requests being active). This possible cookie suppression can be compensated for by adding the SessionID to the URLs either implicately/automatically (via a PHP.INI setting) or explicitly by manually adding them to the URLs in the A/HREFs. There is no mention of this potential problem in the Sessions Section which assumes that the requisite cookie will always be available and thus the problem should at least be mentioned or even better addressed with sample code to manually add the SessionID to the URLs or make more make this inclusion automatic via the PHP.INI settings.