Hi Smcoll, I'd be really interested in knowing what you did in the end to solve this.
On Friday, 24 October 2014 17:24:43 UTC+2, smcoll wrote: > > i'm using django-mptt for a hierarchical model in my app. i've created a > nested serializer for it, but it does not take advantage of MPTT's query > efficiency. It's instead simply using recursive queries. i'd like to know > if there's a way to make that optimization. > > First a little background for those unfamiliar with MPTT: django-mptt > allows me to return an entire hierarchical tree in a single query, by > ordering all the objects from "left to right" and returning their level > (depth in tree) and parent. For example, i have top-level object A which > has three children: B, C, and D. C has two children, E and F. > Myobject.objects.get_descendants(include_self=True) will return a > queryset looking something like this: [<A level=0>, <B level=1>, <C > level=1>, <E level=2>, <F level=2>, <D level=1>] (each node has a > 'parent' explicitly defined, as well). > > The order of the queryset, along with the "level" information, is enough > to draw out the tree structure. For example: > > >>> objectA = MyModel.objects.toplevel().first() # get a root node > >>> for node in objectA.get_descendants(include_self=True): > ... print '%s%s' % (node.level * '--', node) > ... > Object A > --Object B > --Object C > ----Object E > ----Object F > --Object D > > You can imagine what it might look like as a nested JSON object. > > So my question is, how might i approach writing a nested model serializer > that would work the same way, which would require a single query rather > than three recursive queries? Has anyone already solved this? > -- You received this message because you are subscribed to the Google Groups "Django REST framework" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/d/optout.
