How do I use the sql database from other site? like showing the stats of certain field.

Lets say I'm on a forum and wanted to show the number of post I have from a particular forum like trap17 on my own site how do I do that?

You'd have to have read access to that other database on the other site's server and I doubt very much that anyone's going to let you do that, particularly as there's privacy issues involved.

I've seen some sites able to do this as its only showing fields that everyone can see, its publicaly shown like the post count...

You'd still have to get in contact with the admins of the site whose stats you want to use for them to tell you how you would go about it. Probably best sending an email or PM.

This is a very tough one, the only easy way is sending the admins an e-mail and ask if you can fetch some data off their site, but maybe i can help you if you are more specific, url and what kind of fields you want to fetch.

My suggestion would be to open a socket/request connection to trap17 forums using PHP (specifically a URL pointing to your members page "http://www.trap17.com/forums/hype-m5697.html") and once you receive the statically generated content you could store it all in a string and simply parse that string looking for the values you want.. You could gather alot of information about yourself from your member page..

Just a suggestion, I have never actually done it, but it shouldn't be too hard..

Look at this page made by a KoC clan site:

http://www.lordgaldorsclan.net/ranks/index.php?allranks

They made this ranking system with infomation from the Kings of Chaos itself by talking those stats out and placing in their site, but they do not have permission from the admins...