Some time ago i wrote a post about query string and i think i pretty well covered that topic, however i didn’t mentioned one thing … cleaning input variables. In fact it is much more important to know how to clean $_POST and $_GET arrays then know how to handle query string, because variables sent by user are the only way to hack your script, it is that simple, if you take care of input variables then your script is 100% safe.
I very rearly, use feeds, i prefer to go to my favourite website and see what is going on instead of downloading their content to my computer with some RSS reader. However the fact is feeds are getting popular and people are searching for a ways to access and easily automatically parse those feeds with PHP, and because RSS and ATOM are nothing more then XML documents then i have for you really simple way of handling those feeds which i want to share with you (thru my blog as well thru my blog feeds :)).
To be honest i am not a big fan of cheap web hosting, however my web hosting costs me less then 25$ a year! This is about 2$ a month, talk about cheap hosting right? 
Despite the price i am very satisfied with my hosting provider: great customer support and no down times since two years. Hmmm i believe it sounds like a great (or rather obvious) sales page but it is not, mainly because my hosting provider is only available in Poland.
Query strings play important role in building web applications, especially if you want to make nice urls without question mark and many key, value pairs, actually it is not so easy to design application with nice urls however it is always worth doing so, because it not only looks very proffessional, such URLs are search engine friendly, which means that they will get indexed faster but also it happens that search engines have problems with indexing pages with more then 3 key=value pairs in query string.
With each new version PHP is getting more and more object oriented. In version 5.x we get two useful classes for date and time handling. Many programmers are still using outdated methods which are available in PHP mainly for compatibility reasons, so i want to introduce you to DateTime and DateTimeZone objects. (more…)