django - How can I eagerly load an answers latest revision? -


i have q&a site , allows answers changed while storing revision of each change, here on stackoverflow. when selecting answers, i'd include recent(but not all) revision property of each answer, can avoid doing n+1 queries on page. 

class answer(models.model):     user = models.foreignkey(user)     problem = models.foreignkey(problem)  class answerrevision(models.model):     answer = models.foreignkey(answer, related_name='revisions')     text = models.textfield()     timestamp = models.datetimefield()   answer.objects.filter(problem=p)

i'd suggest following structure:

class answer(models.model):     user = models.foreignkey(user)     revision = models.foreignkey(answerrevision)     problem = models.foreignkey(problem)  class answerrevision(models.model):     answer = models.foreignkey(answer, related_name='revisions')     text = models.textfield()     timestamp = models.datetimefield()

the difference added revision property answer. when new revision made, change fk point new revision.


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