我有以下模块：Django中的Sales，性别和Type。
表1：
class Sales(models.Model):
sname = models.CharField(max_length=100, default="-")
sgender = models.ForeignKey(MainGender, on_delete=models.CASCADE)
stype = models.ForeignKey(MainTypes, on_delete=models.CASCADE)
sdate = models.TextField(default="-")
+------+-----+------+------+
| name |gende| type | date |
+------+-----+------+------+
| A | 1 | 1 | 2019 |
+------+-----+------+------+
| B | 2 | 1 | 2018 |
+------+-----+------+------+
| A | 1 | 3 | 2019 |
+------+-----+------+------+
| C | 2 | 3 | 2017 |
+------+-----+------+------+
| A | 1 | 2 | 2019 |
+------+-----+------+------+
表2（键）
class MainGender(models.Model):
mid = models.CharField(max_length=25, default="-")
mgender = models.CharField(max_length=25, default="-")
+----+--------+
| id | gender |
+----+--------+
| 1 | Male |
+----+--------+
| 2 | Female |
+----+--------+
| 3 | - |
+----+--------+
表3（键）
class MainTypes(models.Model):
tid = models.CharField(max_length=50, default="-")
ttype = models.CharField(max_length=50, default="-")
+----+------+
| id | type |
+----+------+
| 1 | U1 |
+----+------+
| 2 | X2 |
+----+------+
| 3 | B1 |
+----+------+
| 4 | H3 |
+----+------+
然后，我要计算主表中的所有内容，并在下面的模板中显示它们
+---------------+---+
| Total records | 5 |
+---------------+---+
| Male | 3 |
+---------------+---+
| Female | 2 |
+---------------+---+
| Type U1 | 2 |
+---------------+---+
| Type X2 | 1 |
+---------------+---+
| Type B1 | 2 |
+---------------+---+
| Type H3 | 0 |
+---------------+---+
我只能通过下面的代码获取模板中的总记录
in views.py
def Sale_p(request):
saless = Sale.objects.all()
return render(request, 'sale.html', {'sales':saless})
我在模板（sale.html）中尝试了这些代码
{{ sales|length }} (gives you total records in Table 1, in this example 5)
{{ sales.gender|length }} (gives nothing)
{{ sales.type|length }} (gives nothing)
{{ sales.gender_set|length }} (gives nothing)
{{ sales.type_set|length }} (gives nothing)
{{ sales.gender(1)|length }} (gives nothing)
{{ sales(gender='1')|length }} (gives nothing)
{{ sales.gender.count() }} (gives nothing)
它们在模板中不起作用。我想在记录中查看我们有“男性”或“女性”或类型等等的次数...
在sale.html模板中
+---------------+--------------------+
| Total records | {{ sales|length }} |
+---------------+--------------------+
| Male | ? |
+---------------+--------------------+
| Female | ? |
+---------------+--------------------+
| Type U1 | ? |
+---------------+--------------------+
| Type X2 | ? |
+---------------+--------------------+
| Type B1 | ? |
+---------------+--------------------+
| Type H3 | ? |
+---------------+--------------------+
要为他人获得结果的代码应该是什么？ 还是应该在views.py中使用其他方式？