Caching dynamic content in Apache (mod_cache)

I'm trying to understand how dynamic caching is done in Apache. I read the Caching Guide of Apache and an article about dynamic caching, but still 开发者_如何学编程don't understand exactly the internals of how dynamic caching works.

Say for example I have a PHP page that serves content through reading from a database according to parameters in the user's URL query-string (or parameters specified in POST).

e.g. www.mySite.com?articleID=31

How is that cached then?

Does mod_cache keeps the content retrieved from the database for this specific article?

Any sources or suggestions are welcomed.

It caches the output of your script, the HTML. What I'm not sure if CacheStorePrivate On will cache PHP scripts with no cache headers. I'm using Apache 2.4.17 and look like it doesn't.