下面的示例主要运用于代码层面的去重处理，不在数据库层面增加唯一键
# 导入依赖
from django.db import models
from django.utils.translation import gettext_lazy as _
from rest_framework.exceptions import APIException
from django.contrib.auth import get_user_modelUser = get_user_model()# 以书名为例
class Book(models.Model):author = models.ForeignKey(User,on_delete=models.CASCADE,related_name='books',verbose_name=_('作者'))name = models.CharField(null=True, blank=True, max_length=255, verbose_name=_('书名'))public_time = models.DateField(null=True, blank=True, verbose_name=_('发行时间'))is_delete = models.BooleanField(default=False, verbose_name=_('是否删除'))def __str__(self):return f'{self.name} - {self.author.name} - {self.public_time}'def clean(self):if not self.is_delete:# 检查是否已有相同的书名、作者 且 is_delete=False 的记录if VersionReviewPlan.objects.filter(author=self.author,name=self.name,public_time=self.public_time,is_delete=False).exclude(pk=self.pk).exists():raise APIException('请检查是否存在相同的书名')def save(self, *args, **kwargs):self.clean()super().save(*args, **kwargs)class Meta:verbose_name = _('书名')verbose_name_plural = _('书名')
