Top Skills: PHP and MySQL ExplainedElance_Keith | Jun 10, 2011
In our quarterly Elance Online Employment Reports, PHP (#1) and MySQL (#6) are regularly among the tip skills ranked based on the number of jobs posted. Just what is driving this incredible demand for professionals in both areas? Hadley Jones, an Elance contractor and business and information technology writer, offers an introduction to the scripting language (PHP) and database system (MySQL), and what users can expect to accomplish when they leverage the two together.
Internet users expect more. They want to be able to make their own choices about what they see and interact with when they visit a website – for example, by displaying the particular kind of products that interest them, or by being able to make comments on a web page about articles in a blog or an online forum. They look for personal treatment from a website, rather than just being served the same old information that anyone else might get. PHP and MySQL are two tools that can help to cost-effectively boost the appeal of any website in this way.
What does PHP change?
Many websites still use the basic technique of HTML (“HyperText Markup Language”) to define how the web pages will be displayed on your computer screen. A web server sends the HTML instructions over the Internet to your PC and the page is displayed by your browser. However, these instructions don’t change. Whether you call up a simple HTML page this week or next week, you’ll see the same static page.
PHP (“PHP: Hypertext Preprocessor”) is programming or “scripting” language that can make that static page into a dynamic one. An additional PHP script of new instructions is inserted into the web page while it’s on the server. The difference is that this PHP script tells the web server what do before it sends the web page to the visitor’s PC. In this way, web pages written with these additional PHP instructions can be different each time a visitor views them, or always updated with the latest information the visitor specifically wants to see. PHP is very popular because it is flexible, powerful and well-designed.
What types of applications can be created with PHP?
The possibilities for creating applications with PHP are endless. For websites, popular examples are:
- Allowing visitors to access specific web pages by entering their user ID and password
- Automatically updating a web page with information that changes, like a currency exchange rate
- Generating statistics so that you know which of your web pages are the most visited
- Managing a online shopping cart for an e-commerce site, so that customers can add different products they want to buy, and then pay online when they are ready
Elance, for example, uses PHP programming. If you go to the Elance Sign In page and click on the word “Forgot?” as though you’d forgotten your password, you’ll see a new page with a name that ends with a “.php” extension: https://secure.elance.com/php/landing/main/forgotPassword.php
A PHP script is then used to send you the password information securely.
Where does MySQL come in?
PHP relies on a separate software program – a database – to hold all the items like product descriptions, prices, blog articles, and so on. A database is a way of organizing a large amount of information to store it reliably and make it available on demand. PHP is flexible and will work with many different database products. One of these products is particularly popular for websites using PHP and it’s called MySQL.
MySQL takes its name from “Structured Query Language” (SQL). In computing terms, this is a standard way of telling a database how to store information and also how to send it back. For example, you can ask for all the blog articles published after a certain date, or all the names of customers who bought a certain product. MySQL is efficient and fast, and it can handle large amounts of data. For using MySQL as part of a commercial or business website, there is a (modest) license fee to be paid. For private use, there is no license fee.
What can you do with a MySQL database?
MySQL can be used to store and retrieve all kinds of information:
- Membership information for a golf club, with selective retrieval to find out who is eligible for different levels of club competition, and who still needs to pay their membership fees.
- Employee information for a business, including HR and payroll records and the possibility to immediately show that wages and taxes have been correctly paid.
- Product inventory for keeping track of how much you have of each product, and how fast each one is selling.
Who uses PHP and MySQL?
You may have already heard of the following applications. But did you know that they use PHP and MySQL as their base?
- WordPress is a software application for creating and running blogs. It can be integrated into a website to provide more of that interaction that is so popular with visitors. It is used by over 14% of the biggest websites worldwide (the top 1,000,000 sites).
- SugarCRM is a Customer Relationship Management (CRM) product for both big and small organizations. It uses MySQL to store information about customers, calls, salespeople, etc. and PHP to manage the interactions.
What do you need to start using PHP and MySQL?
The popularity and low cost of PHP and MySQL as technologies (PHP is free) mean that there is a wide choice of applications already available for businesses. Alternatively, it is possible to “tweak” existing applications or to make new ones for a specific business requirement. Although both PHP and MySQL are relatively easy to use as software applications, they do require a minimum of knowledge about programming. For this reason, it is usually best to use the services of a professional programmer.
It's because they are such popular technologies that there are a large number of PHP and MySQL professionals available for work on Elance. So not only large companies, but small businesses as well can benefit by using PHP and MySQL to make their websites even more attractive to their visitors.
About the Author
Hadley Jones writes on business, information technology and other subjects. A contractor on Elance for the last three years, his background includes working for different international companies in technology and finance with sales, marketing and technical roles. From his base in France he also designs and presents training courses, and creates ebooks, workbooks and website content.