MYSQL Query Cache Not Caching
The mysql query cache can be setup to cache mysql queries. For websites with large quantities of selected data; this can help performance. To set up the cache, click here.
To know what cannot be cached, read on. The mySQL query cache will not cache data that uses non-deterministic functions like now() or current_date(). Furthermore, it won't cache transactions used with InnoDB storage engines. Although, it won't cache some data, it could cache many other chunks of data; such as your home page or other pages on the site.