Django Filter Not Equal in QuerySet: The Best Ways

If you’re working with Django and trying to filter out results that are not equal to a certain value, you may have run into some issues.

This is because while QuerySets contain many built-in operators such as exact to match if a certain value does equal a particular value, there is no filter operator to match if a value does not equal a given value. But luckily, Django provides several options for filtering out results that don’t match certain values.

In this article, we’ll explore these options and provide examples to help you get started.

Using exclude() to Filter Out Results

One way to filter out results that are not equal to a certain value is by using the exclude() method. This method allows you to specify a condition as an argument, which will exclude any results that match that condition.

For example, let’s say we have a model called Product with a field called category. If we want to filter out all products that are not in the clothing category, we could use the following code:

products = Product.objects.exclude(category='clothing')
Code language: Python (python)

This will return all products that are not in the clothing category.

Using filter() and the ~ Operator to Invert a Query

Another option for filtering out results that are not equal to a certain value is to use the filter() method and the ~ operator. The ~ operator allows you to negate a condition, effectively inverting the query. To use the ~ operator, you’ll need to wrap your condition in a Q object.

For example, let’s say we want to filter out all products that are not in the clothing category. We could use the following code:

from django.db.models import Q

products = Product.objects.filter(~Q(category='clothing'))
Code language: Python (python)

Using filter() to Create Complex Queries

You can also use the filter() method to create more complex queries. For example, let’s say we want to filter all products that are not in the clothing category or have a price less than $50. We could use the following code:

products = Product.objects.filter(
    ~Q(category='clothing') | Q(price__lt=50)
)
Code language: Python (python)

This will return all products that are not in the clothing category or have a price less than to $50.

References

• Django documentation on Q objects: https://docs.djangoproject.com/en/3.1/topics/db/queries/#complex-lookups-with-q-objects
• Django documentation on exclude() method: https://docs.djangoproject.com/en/3.1/ref/models/querysets/#exclude