If you went through the examples and experimented a bit, you will start having
better ideas on how to use this newfound flexiblity in your site design.
You should be able to make more sophisticated interfaces, allowing the use
of more complex logical expressions, or even create the entire query
interface based on reading the structure of the database, on-the-fly.
No limit to what you
can do, just remember to have fun and don't get discouraged.
Paraphrasing an old saying: "Inspiration is 10% of the work, debugging the
remaining 90%" (or something like that).
You should check the examples sources available from the "Sample Code" link
in this site. In particular I am impressed by the work done to make the
PHP base library, which now includes
the OOHForms module (highly recommended).
You can get the (IMHO) best web server available from the Apache Project site, and
obtain good SQL databases such as: mSQL,
MySQL, and PostgreSQL from their respective sites.
And of course, keep the PHP manual handy at all times.
You are now on your own pal!