I was checking out Topix.net last night and saw that each news article has the option to leave comments under them. Since all these news articles are fetched from RSS Feeds around the net, how are they able to work in a comment script into each retrieved news article. Hope my question makes sense.
Presumably they fetch the article from the RSS feed and store it in a database, then it's just as if they posted the article on their site.
Interesting. I never thought of that. I'll have to do some research on how to do this. I'm assuming that the database table would have the same fields as those variables in the XML file, correct?
Well, only the fields that are of interest, you might not want to store all of the information. It's not that difficult to do, if you look at Politics Watch you can see where I've syndicated a few political sites - all that happens is a Perl script runs once every two hours, downloads the XML files to disk and then parses them and puts the relevant data into a MySQL table. I can send you the source if you're really interested.
For PHP stuff you probably want to take a look at Magpie RSS. which is a feed parser for PHP. Once you've figured out how to use it, you just need to learn how to insert and select information from databases and the rest of the code is fairly simple.