Datasheet

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Chapter 1: Introduction to PHP and MySQL
As an RDBMS, MySQL can store complex information. As a scripting language,
PHP can perform complicated manipulations of data, on either data that you
need to modify before saving it in the database or data that you retrieved
from the database and need to modify before displaying or using it for
another task. Together, PHP and MySQL can be used to build a sophisticated
and complicated Web database application.
Keeping Up with PHP
and MySQL Changes
PHP and MySQL are open source software. If you’ve used only software from
major software publishers — such as Microsoft, Macromedia, or Adobe —
you’ll find that open source software is an entirely different species. It’s
developed by a group of programmers who write the code in their spare
time, for fun and for free. There’s no corporate office.
Open source software changes frequently, rather than once every year or
two like commercial software does. It changes when the developers feel that
it’s ready. It also changes quickly in response to problems. When a serious
problem is found — such as a security hole — a new version that fixes the
problem can be released in days. You don’t receive glossy brochures or see
splashy magazine ads for a year before a new version is released. Thus, if you
don’t make the effort to stay informed, you could miss the release of a new
version or be unaware of a serious problem with your current version.
Visit the PHP and MySQL Web sites often. You need to know the information
that’s published there. Join the mailing lists, which often are high in traffic.
When you first get acquainted with PHP and MySQL, the large number of mail
messages on the discussion lists brings valuable information into your e-mail
inbox; you can pick up a lot by reading those messages. And soon, you might
be able to help others based on your own experience. At the very least, sub-
scribe to the announcement mailing list, which delivers e-mail only occasion-
ally. Any important problems or new versions are announced here. The e-mail
that you receive from the announcement list contains information you need to
know. So, right now, before you forget, hop over to the PHP and MySQL Web
sites and sign up for a list or two at www.php.net/mailing-lists.php and
lists.mysql.com.
PHP versions
The current version of PHP is PHP 5. Some existing applications still run
PHP 4, but because you’re building your first PHP application, you should be
using PHP 5.
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