非空约束失败完整性错误

Question

嗨，我在弄清楚如何解决此错误时遇到了麻烦。我正在创建一个表单，以便能够向正在工作的网站添加新主题。创建表单并尝试使用它提交添加新主题的请求后，我遇到了一个完整性错误，以前从未遇到过。经过研究后，我知道它与外键关系有关，在外键关系中，数据库内部有一个空字段，但我不确定如何导致该根。

这是我的Models.py文件：

<input type="text" name="regDate" value=<%= "\""+cal.getTime()+"\"" %> />
<% cal.add(Calendar.YEAR, 1); %>
<input type="text" name="endDate" value=<%= "\""+cal.getTime()+"\"" %> />

forms.py

from django.db import models

# Create your models here.


class Category(models.Model):
    """A category the user is writing about"""
    text = models.CharField(max_length=200)

    class Meta:
        verbose_name_plural = 'Categories'

    def __str__(self):
        """Return a string represtation of the model."""
        return self.text


class Topic(models.Model):
    """A topic that is associated with a certain Category"""
    category = models.ForeignKey(Category, on_delete=models.CASCADE)
    text = models.CharField(max_length=200)
    date_added = models.DateTimeField(auto_now_add=True)

    class Meta:
        verbose_name_plural = 'Topics'

    def __str__(self):
        """Return string represtation of the model."""
        return self.text


class Entry(models.Model):
    """A entry associated with a certain topic"""
    topic = models.ForeignKey(Topic, on_delete=models.CASCADE)
    text = models.TextField()
    date_added = models.DateTimeField(auto_now_add=True)

    class Meta:
        verbose_name_plural = 'Entries'

    def __str__(self):
        """Return string represtation of the model."""
        return self.text[:50] + "..."

views.py

from django import forms
from .models import Category, Topic


class CategoryForm(forms.ModelForm):
    class Meta:
        model = Category
        fields = ['text']
        labels = {'text': ''}


class TopicForm(forms.ModelForm):
    class Meta:
        model = Topic
        fields = ['text']
        labels = {'text': ''}

感谢您帮助我指出正确的方向！

选择类别

将新主题添加到类别