Django实战-调查问卷表设计

from django.db import models
from django.contrib.contenttypes.fields import GenericForeignKey, GenericRelation
from django.contrib.contenttypes.models import ContentType

class Survery(models.Model):
    """
    问卷
    ID        name            by_class      creator
    1    第一次班级调查      大一计算机205班     张老师
    """
    name = models.CharField(verbose_name="调查问卷名称", max_length=128, unique=True)
    by_class = models.ForeignKey("ClassList", verbose_name="问卷调查班级", on_delete=models.SET_NULL)
    date = models.DateTimeField(verbose_name="问卷创建日期", auto_now_add=True)
    creator = models.ForeignKey("UserInfo", verbose_name="创建者", on_delete=models.SET_NULL)

class SurveryItem(models.Model):
    """
    问卷题目
    ID                 survery                       name                   date          answer_type
     1    1(代表上面创建的第一次班级调查)      您最喜欢吃什么水果?         xxx-xxx-xx             1
     1    1(代表上面创建的第一次班级调查)      您最喜欢看什么书籍?         xxx-xxx-xx             2
     1    1(代表上面创建的第一次班级调查)      您最喜欢什么英雄人物?       xxx-xxx-xx             3
    """
    survery = models.ForeignKey('Survery', verbose_name='问卷', on_delete=models.SET_NULL)
    name = models.CharField(verbose_name="调查问题", max_length=255)
    date = models.DateField(auto_now_add=True)
    answer_type_choices = (
        (1, "打分(1~10分)"),
        (2, "单选"),
        (3, "建议"),
    )
    answer_type = models.IntegerField(verbose_name="问题类型", choices=answer_type_choices, default=1)

class SurveryChoices(models.Model):
    """
    问卷选项答案(针对选项类型)
    ID    item    content   points
    1       2       A         10分
    1       2       B         9分
    1       2       C         8分
    1       2       D         7分
    """
    item = models.ForeignKey('SurveryItem', verbose_name='问题', on_delete=models.SET_NULL)
    content = models.CharField(verbose_name='内容', max_length=256)
    points = models.IntegerField(verbose_name='分值')

class SurveryRecord(models.Model):
    """
    问卷记录
    ID    survery      student_name   survery_item  score  single  suggestion  date
    1        1            1               1          10分   null      null    xxxxx     
    1        1            1               2          null     A       null    xxxxx     
    1        1            1               3          null   null      XXXXX    xxxxx     
    """
    survery = models.ForeignKey('Survery', verbose_name="问卷", on_delete=models.SET_NULL)
    student_name = models.ForeignKey('Student', verbose_name="学生姓名", on_delete=models.SET_NULL)
    survery_item = models.ForeignKey('SurveryItem', verbose_name="调查项", on_delete=models.SET_NULL)

    score = models.IntegerField(verbose_name="评分", blank=True, null=True)
    single = models.ForeignKey('SurveryChoices', verbose_name='单选', blank=True, null=True, on_delete=models.SET_NULL)
    suggestion = models.TextField(verbose_name="建议", max_length=1024, blank=True, null=True)

    date = models.DateTimeField(verbose_name="答题日期", auto_now_add=True)