Loading Rails activerecord associations from memcache
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Ive 2 models in my app - a Request and a Category
A Request belongs to a Category. The system contains many requests but only a few categories. The categories are static and never change and they hold other associations which are also static. I can use memcache to store the category and related associations.

How do I tell rails when it loads a particular Request to load the associated Category from memcache and not the DB ?

    req = Request.find(id)
    req.category (Curr this hits the DB - want it to hit memcache)

Is overriding the method req.category the only way ?