Filtering with django-filter - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is django-filter used for in Django projects?

django-filter helps you add easy and reusable filtering to your Django views. It lets users pick which data they want to see by filtering querysets based on form inputs.

beginner

How do you create a basic filter class using <code>django-filter</code>?

<p>You create a class that inherits from <code>django_filters.FilterSet</code>. Inside, you define which model and fields to filter. For example:</p><pre>import django_filters

class ProductFilter(django_filters.FilterSet):
    class Meta:
        model = Product
        fields = ['category', 'price']</pre>

intermediate

How do you connect a django-filter filter to a Django view?

In your view, you create a filter instance with the request's GET data and the queryset. Then you use the filtered queryset in your context. Example:

filter = ProductFilter(request.GET, queryset=Product.objects.all())
products = filter.qs

beginner

What is the benefit of using django-filter over manual filtering in views?

django-filter automatically creates filter forms and handles filtering logic. This saves time, avoids errors, and keeps your code clean and reusable.

intermediate

Can django-filter handle complex filters like ranges or multiple choices?

Yes! You can use special filters like RangeFilter for ranges or MultipleChoiceFilter for selecting many options. This lets users filter data in flexible ways.

What base class should you inherit from to create a filter class in django-filter?

A django_filters.FilterSet

B django_filters.FilterForm

C django_filters.FilterView

D django_filters.FilterModel

The correct base class is django_filters.FilterSet. It defines which model and fields to filter.

How do you apply filters from the URL query parameters in a Django view using django-filter?

A Filters do not use request data

B Use <code>request.POST</code> in the filter

C Manually parse the URL string

D Pass <code>request.GET</code> to the filter class

Filters use request.GET to read query parameters for filtering.

Which django-filter feature automatically creates a form for filtering?

A FilterView

B FilterSet

C FilterForm

D FilterModel

FilterSet generates a form based on the fields you specify for filtering.

What does filter.qs represent in django-filter?

A The filtered queryset after applying filters

B The original unfiltered queryset

C The filter form HTML

D The filter class instance

filter.qs is the queryset filtered by the user's input.

Which filter type would you use to allow filtering by a price range?

A BooleanFilter

B ChoiceFilter

C RangeFilter

D CharFilter

RangeFilter lets users filter between two values, like a price range.

Explain how to set up filtering in a Django view using django-filter.

Think about how the filter connects the URL parameters to the data shown.

Describe the advantages of using django-filter instead of writing manual filtering code.

Consider how django-filter helps with both user interface and backend logic.