queries in Django’s views and template

Question

I have two tables (Client) and (Animal), the animal table is related through a Foreign key with the Client table, currently I can register only client, register client and animal together, in the list screen I can list the data of the client table and data of the animal table including the clients that are related to the animal, however I would like to list now only the clients that do not have the registered animal: follows below my models.

models

 class Cliente(models.Model):

    codigoCliente = models.AutoField(primary_key=True, blank=False)
    nome = models.CharField(max_length=50, null=False, blank=False)
    sobrenome = models.CharField(max_length=50, null=False, blank=False)
    rg = models.CharField(max_length=9, null=False, blank=False)
    cpf = models.CharField(max_length=11, null=False, blank=False)
    dataNascimentoCliente = models.DateField(null=True, blank=True, verbose_name='Data de Nascimento')
    numeroTelefoneFixo = models.CharField(max_length=11, null=True, blank=True, verbose_name='Telefone Fixo')
    numeroTelefoneCelular = models.CharField(max_length=11, null=True, blank=True, verbose_name='Telefone Celular')
    email = models.EmailField(max_length=100, unique=True, null=False, blank=False)
    cep = models.CharField(max_length=8, null=False, blank=False)
    endereco = models.CharField(max_length=100, null=False, blank=False)
    cidade = models.CharField(max_length=100, null=False, blank=False)
    bairro = models.CharField(max_length=100, null=False, blank=False)


    def __str__(self):
        return '{}, {}'.format(self.nome, self.sobrenome)

    def __repr__(self):
        return '{}, {}'.format(self.nome, self.sobrenome)


 class Animal(models.Model):

    codigoAnimal = models.AutoField(primary_key=True, blank=False)
    nomeAnimal = models.CharField(max_length=50, null=False, verbose_name='Nome do Animal')
    dataNascimentoAnimal = models.DateField(null=True, blank=True)
    pelagem = models.CharField(max_length=10, choices=PELAGEMCHOICES)
    especie = models.CharField(max_length=100, null=True, blank=True)
    raca = models.CharField(max_length=50, null=False, verbose_name='Raça')
    sexo = models.CharField(max_length=10, choices=SEXOCHOICES)
    deficiencia = models.CharField(max_length=10, choices=DEFICIENCIACHOICES)
    descreva = models.TextField(null=True, blank=True)
    imagem = models.ImageField(upload_to='imagens', null=True, blank=True, verbose_name='Foto do Animal')

    cliente = models.ForeignKey(Cliente, on_delete=models.CASCADE)

    def __str__(self):
        return '{}, {}'.format(self.nomeAnimal, self.raca)

    def __repr__(self):
        return '{}, {}'.format(self.nomeAnimal, self.raca)

views

@login_required(login_url='/login/')
def consultaRegistro(request, template_name='consultaRegistro.html'):

    animal = Animal.objects.all()
    cliente = Cliente.objects.all()

    return render(request, template_name, {'cliente': cliente, 'animal': animal  }

template****

                    <tr>
                      <th>ID Cliente</th>
                      <th>Cliente</th>
                      <th>Animal</th>

                    </tr>
                     {% for a in animal %}

                    <tr>

                      <td><a href="/consultaDetails/{{ xxxxxxxxx }}/">{{ a.cliente.codigoCliente }}</a></td>
                      <td><a href="/consultaDetails/{{ xxxxxxxxx }}/">{{ a.cliente.nome }}</a></td>
                      <td><a href="/consultaDetails/{{ xxxxxxxxx }}/">{{ a.nomeAnimal }}</a></td>


                    </tr>
                     {% endfor %}


                     {% for c in cliente %}


                    <tr>

                      <td><a href="/consultaDetails/{{ xxxxxxxxxx }}/">{{ c.codigoCliente }}</a></td>
                      <td><a href="/consultaDetails/{{ xxxxxxxxx }}/">{{ c.nome }}</a></td>
                      <td><a href="/consultaDetails/{{ xxxxxxxxx }}/">{{ a.nomeAnimal }}</a></td>


                    </tr>

                     {% endfor %}

Answer 1

The query would be like this:

Cliente.objects.filter(animal__isnull=True).all()

You can reference the foreign key directly.