I have a dynamic website where the page content changes every few minutes. Will googlebot scan and index my site properly? I am planning to cache the page data to a database for seven days every time googlebot, msnbot and inktomi comes around. Is that a good idea? Will google penalize my site?
You won't get penalised for rapidly changing content. The more frequently content changes on a website the more often Google is inclined to come back to it. If the content is changing drastically you are at disadvantage in that Google will always have old content in its cache.
I agree but if you still retain those files or content, well it is much better to create fake urls that will be resolved by mod_rewrite to it's corresponding dynamic urls Hope it Helps