Report Model

    We start by a model that contains the data we want to analyze.

    Consider this example SalesLog model
    

class SalesLineTransaction(models.Model):
    """
    Sales Log
    """
    slug = models.SlugField(_('Code'), max_length=50, db_index=True, validators=[], blank=True)
    transaction_date = models.DateTimeField(_('Date'), db_index=True)
    client = models.ForeignKey(Client, on_delete=models.CASCADE)
    product = models.ForeignKey(Product, on_delete=models.CASCADE)
    quantity = models.DecimalField(_('Quantity'), max_digits=19, decimal_places=2, default=0)
    price = models.DecimalField(_('Price'), max_digits=19, decimal_places=2, default=0)
    value = models.DecimalField(_('Value'), max_digits=19, decimal_places=2, default=0)

    def save(self, force_insert=False, force_update=False, using=None, update_fields=None):
        self.value = self.price * self.quantity
        super().save(force_insert, force_update, using, update_fields)

    class Meta:
        verbose_name = _('Sale log')
        verbose_name_plural = _('Sales logs')


class Client(models.Model):
    slug = models.SlugField(_('Code'), max_length=50, unique=True, db_index=True, blank=True)
    name = models.CharField(_('Name'), max_length=255, unique=True, db_index=True)


    class Meta:
        verbose_name = _('Client')
        verbose_name_plural = _('Clients')

    def __str__(self):
        return self.name


class Product(models.Model):
    slug = models.SlugField(_('Code'), max_length=50, unique=True, db_index=True)
    name = models.CharField(_('Name'), max_length=255, unique=True, db_index=True)

    class Meta:
        verbose_name = _('Product')
        verbose_name_plural = _('Products')

    def __str__(self):
        return self.name

                

Results