performance - Selecting a random row in Django, quickly -

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i have view returns data associated randomly-chosen row 1 of models. i'm aware of order_by('?') , performance problems, , want avoid using order_by('?') in view.

because data in model changes (if @ all), i'm considering approach of caching entire model in memory between requests. know how many records i'm dealing with, , i'm comfortable taking memory hit. if model change somehow, regenerate cache @ moment.

is strategy reasonable? if so, how implement it? if not, how can select random row model changes if @ all?

if know ids of object, , range can randomize on ids, , query database


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