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PODjango, simple way to query one to many relationships?
 

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    <p>So I want to return a dict in javascript of two tables a Category table and a Sub_category table with category = models.ForeignKey(Category). The dictionary so be 'Category1': 'Sub_cat1, Sub_cat2, ...'. I did the following code, but it seems very inefficient, so could you guys help me find another way to do this?</p> <p>Thanks!</p> <pre><code>from models import Sub_category, Category # Extra unnecessary query? def get_json_sub_categories(category): return get_json(Sub_category.objects.filter(category_id=Category.objects.filter(name=category).values('pk')[0]['pk']).values('name')) </code></pre> <p>Added: The dictionary should contain all categories and their respective sub categories. I could probably create a loop or something and call a query for each Category but that's a lot of queries. Is there one query that could get me all the Categories and their respective sub categories in a dictionary style?</p> <p>I did this instead:</p> <pre><code>from models import Sub_category, Category import json def get_sub_categories(): return Sub_category.objects.all().values('name', 'category__name') def get_dict_sub_categories(): sub_dict = {} sub_queryset = get_sub_categories() for x in sub_queryset: if x['category__name'] not in sub_dict: sub_dict[x['category__name']] = [x['name']] else: sub_dict[x['category__name']].append(x['name']) return sub_dict def get_json_sub_categories(): return json.dumps(get_dict_sub_categories()) </code></pre> <p>Anything more efficient/faster? Does my code look okay? I'm also assuming this is done with only one query. Is this true?</p>
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Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

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