$stmt = $db->stmt_init();
$sql = 'SELECT username FROM users WHERE username = ?';
$stmt->prepare($sql);
$stmt->bind_param('s', $_POST['username']);
$stmt->execute();
$numrows = $stmt->num_rows;

The code worked without error, so it wasn’t immediately obvious why $numrows was always 0. So, I checked the PHP documentation for mysqli_stmt::num_rows. The description is rather ambiguous in that it refers only to the need to store the result when using the procedural style, but the object-oriented example makes it clear that you need to call the store_result() method before accessing the num_rows property. When I changed my code like this, I got the expected result:

$stmt = $db->stmt_init();
$sql = 'SELECT username FROM users WHERE username = ?';
$stmt->prepare($sql);
$stmt->bind_param('s', $_POST['username']);
$stmt->execute();
// store result of prepared statement
$stmt->store_result();
$numrows = $stmt->num_rows;

At first, it seemed counterintuitive to store a result that I was going to throw away, but that’s how num_rows works with a MySQLi prepared statement. Thinking about it a bit more, it makes sense because if you use the MySQLi query() method instead of a prepared statement, you store the result in a MySQLi_Result object and get the number of rows from the result like this:

$sql = 'SELECT user_id, name, username FROM users';
$result = $db->query($sql);
$numrows = $result->num_rows;

There’s no charge to participate. The only cost is buying a copy of my book. Although I have Amazon affiliate links on my website, I encourage you to buy it through the Boston PHP Store. That way, the organizers get a small commission that helps support the activities of Boston PHP.

The way it works is that you commit to reading one chapter of the book (there are 17) and completing the exercises each week. There’s no classroom instruction, but you can get online support through a dedicated forum for each chapter. Also, if you live in the Boston area (the one in Massachusetts, not the one in Lincolnshire or more than a dozen other places), you can get hands-on help at the PHP Percolate Coffee Club, which is usually held every Saturday morning at a Starbucks. Boston PHP also runs occasional all-day events known as Developer Dorm Room in Cambridge, Massachusetts, where you can get help with PHP problems or just bounce ideas about projects off each other.

Although PHP Percolate is based on my book, this isn’t a wacky marketing idea that has been dreamed up by me or my publisher. It’s an idea that Boston PHP came up with independently. In fact, I didn’t learn about it until quite recently. According to the President of Boston PHP, Michael Bourque, Boston PHP is the largest and most active PHP tech community in the world, with more than 1,900 members. It has a focus on education and adoption of open source technology like PHP. Last year, they were looking for the best possible book to learn PHP, and mine was the one they chose. Naturally, I’m delighted, and I have agreed to help in whatever way I can.

Unfortunately, there’s a small matter of the Atlantic Ocean lying between me and Boston, so I won’t be able to attend the PHP Percolate Coffee Club or Developer Dorm Room in person. But that’s one of the joys of the internet. You don’t need to be there in person to share ideas and cooperate with others. From what I understand, PHP Percolate has also attracted people from other countries to join in. A book and an internet connection is all you need.

Committing to working through 17 chapters in as many weeks is a lot to ask. Work, family, and other obligations get in the way. So, not everybody manages to last the whole course. But since there’s no cost (apart from the book), there’s little to lose. In fact, I see that some of the people who dropped out part of the way through season 2 have signed up again for season 3. As one of them said, “It’s fun!”

So, if you’re looking for a little bit of moral support in your efforts to learn PHP, check out PHP Percolate Season 3 with Boston PHP.

I spent most of the summer going through every chapter and all the code line by line, correcting errors and making the code more efficient. The result is a major rewrite, PHP Solutions: Dynamic Web Design Made Easy, Second Edition, which is now in stock at Amazon in the United States, and should be available elsewhere soon. It’s also available in electronic form as a Kindle version, or as a PDF from the friends of ED website.

There’s a detailed description of what the book covers and how it differs from the first edition elsewhere on this site. If you have recently bought the first edition, don’t worry. There’s nothing actually wrong with the original code, but do make sure you check the updates on my site, as well as the corrections on the friends of ED site.

When downloading the accompanying files from friends of ED, make sure you get the files for the correct edition:

• Download files for PHP Solutions, Second Edition
• Download files for PHP Solutions, First Edition

If you have a Safari Library subscription, you can view the chapters free of charge, and see new ones as they’re added. Without a subscription, you can get access to the book in PDF format for $34.99, including the finished ebook version when the book is complete. You can also opt for the Rough Cuts PDF and Print bundle for $67.48. The print version is expected to be released in early August.

The chapters currently available are Lessons 1-3 and 4-7, covering the following subjects:

• An in-depth look at all the PHP features in Dreamweaver CS5
• Instructions for setting up a local PHP development environment
• A quick PHP crash course (or refresher)
• Creating your own database in MySQL
• Using Dreamweaver server behaviors for automatic code generation
• Building a robust user registration system with Zend_Validate and Zend_Db

Chapters still to come concentrate heavily on using selected modules of the Zend Framework for sending email, uploading files, and building a content management system. (To avoid any misunderstanding, the book does not use the MVC design pattern—it follows what the ZF documentation calls “use at will” design, making use of individual components.)

I answer a lot of questions in the Dreamweaver forums, and realized that a lot of the solutions I was coming up with for people weren’t easy to find after a couple of days. So, rather than letting them disappear into cyberoblivion, I decided to add any of general interest to the cookbook when I had a few spare moments. The Dreamweaver Cookbook is intended for code samples, and doesn’t have the capability of including screenshots, so I’ll continue posting longer tutorials on my own site. But I hope you’ll find my contributions to the cookbook useful.

Here are direct links to some of the articles I have added to the Dreamweaver Cookbook:

• Create nested lists from a recordset
• Set a time limit on a login session
• Registration system that requires the user to validate the email address (in two parts)
• Alternate colours for table rows (using PHP, Spry, or jQuery)
• Upload image to website
• Format date for insertion into MySQL
• Formatting dates stored in MySQL

The Dreamweaver Cookbook is open to anyone to either request recipes or contribute recipes of their own. It could turn into a very useful resource if people start using it regularly. Check it out!

I’ll create a full tutorial on the revised procedure when I get time, but you can find a summary of the main differences on the updates page for The Essential Guide to Dreamweaver CS4.

If you turn magic quotes off in PHP—which you should—you won’t be affected by this bug. It serves as a reminder that magic quotes are due to be removed in PHP 6. Magic quotes were originally introduced to make life “easier” for inexperienced developers by automatically inserting a backslash in front of single and double quotes in user input to prevent problems with database insertion. However, they have proved more trouble than they’re worth. Instead of magic quotes, you should use dedicated functions, such as mysql_real_escape_string(), or prepared statements with MySQLi or PDO to handle quotes and other special characters and protect your database from SQL injection attacks.

The main changes affecting the phpMyAdmin user interface concern the creation of new tables. They can be summarized as follows:

• When setting a default value for a column (field), you need to select a value from the drop-down menu. The options are None, As defined, NULL, or CURRENT_TIMESTAMP. If you select As defined, type the default value you want the column to have in the field immediately below.
• As before, phpMyAdmin treats all columns as NOT NULL. In other words, all columns require a value to be inserted in them. To make a column optional, select the Null checkbox. In the version 2 series, this was a drop-down menu.
• To set an index on a column, choose the appropriate index type from the Index drop-down menu. The choices are PRIMARY, UNIQUE, INDEX, and FULLTEXT. In the version 2 series, these were represented by radio buttons.
• To create an auto incrementing column (normally used in conjunction with a primary key), select the A_I checkbox. In the version 2 series, this was a drop-down menu called Extra.

Anybody using my book Foundation PHP for Dreamweaver 8 should get the hotfix pronto, as it solves two problems affecting Chapters 9 and 12:

• Without the hotfix, Dreamweaver 8.0.2 strips CONCAT() out of SQL queries.
• Changes in the way PHP 5.1.4 and above handles XML resulted in the XSL Transformatiion server behavior reporting incorrectly that the source was not a valid XML document.

The hotfix also solves a couple of other important problems, so if you have Dreamweaver 8.0.2 or have been putting off updating to 8.0.2, I strongly urge you to get in touch with Adobe support and get the hotfix. You can find full details in this technote on the Adobe site.

The dates had been entered incorrectly into the test table, so the actual values were 0000-00-00 00:00:00. No wonder that DATE_FORMAT() wasn’t able to convert them. However, the nasty problem with Dreamweaver 8.0.2 corrupting SQL queries that use CONCAT() has been confirmed by several people. Let’s hope it gets fixed soon.