Php, MySql, .htaccess: friendly urls
There are a lot of tutorials that show how to change an address like:
into others like:
In this article I’d like to go one step forward and to create something like:
How-To and Contraindications
Switching from an address like the first one to the secon ones is search engine necessary, because SE spiders often don’t crawl correctly our dynamic urls. Switching to the third ones is much better, because it’s a search engine friendlier, and it’s human friendly too.
Now, I think we all agree that we should change our dynamic urls into the last ones, but the goal is to make it without modifying, or at least without modifying too heavily our web application. If our php script works with a query for product_id, and product_id is the unique, autoincremental key of our mysql database, we have to rewrite our urls without losing the possibility for our script to work in its original way.
That is the way WordPress works: a function that allows the user to choose the preferred format for the urls. In this tutorial, we replicate – in a very simplier way – that tool.
How the system works
My solution – with downloadable example – uses php and mysql to manage the content and create the urls, and Apache’s server mod_rewrite module to rewrite the addresses. We assume to be on a linux server and that our app is php and mysql based.
We have 2 tables in our mysql db:
News table contains the articles, with the columns id, title, article and slug, where slug contains the sanityzed title, that is a title like: “That’s an easy mod_rewrite tutorial” becomes “thats-an-easy-mod-rewrite-tutorial”.
The script, normally, queries the db for the id, but we, through php, will find the related slug. Then we rewrite the url through mod_rewrite.
Options table contains id, name and value of the options, that is, in this example, permalinks yes/no. If permalinks are off, php will query the db for the id, and the url format will be: index.php?id=x. If permalinks are on, php will query mysql for the slug, and mod_rewrite will rewrite the url in format: rewritten-url-with-php-and-mod-rewrite.
A working example is available at:
Also downloadable in .zip format at:
Example includes following files:
Very simple .htaccess for mod_rewrite, that transforms the url from ?slug=rewritten-url to /rewritten-url.
If permalinks are off, url format will be ?id=x, and there will be no rewrite.
The file with the basic tool to switch on/off the permalinks
- single.php and index.php
Show site contents.
Contains the function that generates the urls (rewritten or not, depending on permalinks selected status) and the function that gets the articles from mysql database.
- Zip file also includes the .sql file to recreate the example datatabase.