Devlog

I get asked about this a lot. Why did I take the PHP Certification exam? What does it do for me? Was it hard?

The Zend PHP Certification is basically a badge that says “I know my stuff”. Zend’s site actually has a pretty good summary of the benefits of becoming certified.

I became certified for a couple of reasons (other than me being an egotistical bastard). I wanted to test myself and make sure I was actually up to date with everything. I came into the world of PHP around version 4.1. Since then a lot has changed, especially with the advent of PHP5. Taking the practice exams I discovered that there were a few areas I definitely needed to improve upon. For example, primarily working on products that needed to run under a PHP4, I never had much experience with the new XML features.

The other reason was that the exam was really cheap for the possible benefit. Noted, the Zend PHP Certification is hardly mentioned at all by employers. It is relatively new as far as certifications go. But by sticking that badge on your resume, you automatically have a one-up over your adversaries. PHP programmers are a dime a dozen these days, and most of them only know enough to slap together something that barely works. If a possible client knows you’ve passed the official PHP Certification exam, it gives you some credibility. $125 is a small price to pay. You can make that back in just a single job.

Preparation

I know you’re thinking it. Everyone whose asked me about the exam always asks “was it hard?”. For me, it was simple. I found it really easy. But I’ve been working with PHP for a long long time, so obviously your milage may vary (it’s all relative, after all).

What you really need to do is a little research. I ended up buying the bundle which included the study guide, 10 practice exams, and the actual exam voucher. It’s a pretty good deal, I encourage anyone interested in taking the exam to do the same.

The study guide was not bad. It’s basically a quick walkthrough over the entire language. But the practice exams were really useful. The practice exams tell you if you’re really ready to take the real thing. I can tell you, they are very very close to the real exam; they are actually a bit harder. If you pass the practice exams, you will surely pass the real exam.

After you finish a practice exam, you get a scorecard telling you which areas you passed, which you failed, and which you did excellent in. For me, this scorecard revealed I needed to brush up with SimpleXML.

I should mention that the exam is a pass or fail thing. There are no grades. My PHP Certification can not be better than yours. So just because you get “pass” instead of “excellent” doesn’t really matter unless your ego requires it (like mine!).

What you should know

The Zend website has an overview of the topics covered by the exam. Of course you need to know every inch of PHP, but I will point-out/stress:

• Regular expressions: You should know some basic regex.
• SQL: You will need to know some basic SQL, and how it works (i.e., fetching rows with PDO). Some topics you might need to brush up on include indexes, table joins and transactions. You don’t need to be a DBA to pass the exam, but you should know how to work with a database.
• How numbers are represented in hex or octal notation. I mention this here because a lot of us don’t need to worry about hex or octal notation in PHP.
• How the bitwise operators work.
• Differences between PHP4 and PHP5. There are a bunch of little nuances here that you may be asked about.
• Security: You should know things like how to avoid XSS, session fixation, filtering input, validation etc.
• XML: There may be a number of questions about XML, XPath, SimpleXML etc. If you’ve been working with PHP4 a lot, then it’s time to get in tune with the improvements PHP5 introduced.
• PDO: If you’ve been working with a database abstraction layer (which is probably just about everyone reading this), then you probably will need to read up on how PDO works.
• There may be a few questions regarding software architecture such as design patterns (MVC for example), OOP principals etc.
• Streams and network programming is something you will probably need to look into a bit.

Who should take the exam

You should only take the exam if you actually know PHP well. It does an excellent job at weeding out the half-assed PHP programmers, so don’t even attempt it unless you know your stuff already. If you are just starting out, or are of average skill, your money would be best spent buying some other material like Advanced PHP Programming.

You should take the exam if you are a freelancer, or looking for work. I think it definitely does give you a heads up over your competition. Even if you have other credentials. Case in point: recently I was looking for a new programmer to help develop a product I work on. One applicant was a CS major, but was an absolutely horrible programmer. You might have passed a few college classes, but that doesn’t mean much to me. I need to know that you can deliver.

You should take the exam if you want to test yourself, like I did. It is certainly a good way to discover your weaknesses and your strengths. You might find multiple areas where you had no experience.

So with all that said, good luck!