Performance - XML parsing or database calls

[eluser]xwero[/eluser]
[quote author="dpgtfc" date="1228594456"]Anyway, right now, on every load of a page there is a database call. I think this would open my application up to a DOS attack, no? Even so, for performance issues, I have considered using XML.
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You are describing a clear cut case of premature optimization.

There is nothing wrong with wanting to make as less database queries as possible but if you are afraid to get data out the database you better make static pages. And about the DOS attack, that is FUD. The database is not the only resource that is affected by a DOS attack.

About the performance, first benchmark your queries and you can always use cache if your site has a lot of traffic. Caching is much faster than parsing xml or json.