sqlachemy:按关系过滤(比如django orm)?

class Product(models.Model):
    product_id = models.IntegerField(primary_key=True)
    color = models.TextField()

class Sale(models.Model):
    sale_id = models.IntegerField(primary_key=True)
    timestamp = models.DateTimeField()
    product = models.ForeignKey(Product, on_delete=models.CASCADE)

你能做到的

Sale.objects.filter(product__color__in=['red', 'blue'])

甚至相反

Product.objects.filter(sale__timestamp__gt=datetime.now())

没有显式联接 s??