经验总结

  1. 首页 > 生活 > >

插拔式 Django之同时新增数据到两个数据库表与同时返回两个表的数据

生活百科

  • models：比如有以下三个模型
from django.db import models"""基类，其他类继承即可获得对应的字段"""class BaseModel(models.Model):updated_tm = models.DateTimeField(auto_now=True)created_tm = models.DateTimeField(auto_now_add=True)class Meta:abstract = True"""项目列表"""class ProjectList( BaseModel):project_id = models.AutoField(help_text="项目ID", primary_key=True)project_name = models.SlugField(max_length=128, help_text="项目名称", unique=True)class Meta:db_table = 'project_list'verbose_name = '项目列表信息'verbose_name_plural = verbose_name"""项目详情"""class ProjectDetail(BaseModel):project_introduction = models.CharField(max_length=128, help_text="用户简介")project_info = models.ForeignKey(to=ProjectList, on_delete=models.DO_NOTHING, db_constraint=False, related_name='user')class Meta:db_table = project_detail'verbose_name = '项目详情信息'verbose_name_plural = verbose_name一、同时新增数据到两个数据库表
  • views
from rest_framework import filters, mixins, genericsfrom rest_framework.viewsets import GenericViewSetclass ProjectListView(mixins.CreateModelMixin, GenericViewSet):queryset = Account.objects.filter(is_delete=0).all().order_by("-created_tm")def create(self, request, *args, **kwargs):# 先定义两个dictproject_list_dict = {}project_detail_dict = {}# 使用 ._meta.get_fields() 获取数据库表的全部字段，再使用field.name获取全部的字段名称，放入各自的dict，不存在的自动忽略掉for item in request.data.items():if item in [field.name for field in ProjectList._meta.get_fields()]:project_list_dict [item[0]] = item[1]elif item in [field.name for field in ProjectDetail._meta.get_fields()]:project_detail_dict [item[0]] = item[1]# 从上面的models可以看到，项目详情与项目列表两张表是有关联的，所以，新增数据的时候，先现在列表，新增成功，生成ID后，再新增详情，并通过ID与列表数据关联起来# 检查项目是否存在，项目名称唯一约束，Serializer内设置必填try:# 存在就直接失败ProjectList.objects.get(project_name=request.data.get('project_ame'))return xxxexcept Account.DoesNotExist:# 如果不存在，先调用ProjectList表新增数据try:project_create = ProjectList.objects.update_or_create(defaults=project_list_dict, project_name=project_list_dict["project_ame"])# 如果ProjectList表新增数据成功，则通过project_info，在ProjectDetail新增对应的数据if project_create:project_id = ProjectList.objects.filter(project_name=project_list_dict["project_ame"]).values('project_id').first()ProjectDetail.objects.update_or_create(defaults=project_detail_dict, project_info=project_id["project_id"])return xxxexcept Exception as e:return e二、同时返回两个表的数据(插拔式)
  • 插拔式的好处：即插即用，需要时才调用，不需要则不调用
  • 从ProjectDetail这个models我们可以看到，是没有定义project_id和project_name的，但我们是与ProjectList关联的，所以，我们可以通过project_info，返回ProjectList已定义的project_id和project_name
【插拔式 Django之同时新增数据到两个数据库表与同时返回两个表的数据】# 我们只需要把ProjectDetail改成以下这样子就可以了class ProjectDetail(BaseModel):project_introduction = models.CharField(max_length=128, help_text="用户简介")project_info = models.ForeignKey(to=ProjectList, on_delete=models.DO_NOTHING, db_constraint=False, related_name='user')class Meta:db_table = project_detail'verbose_name = '项目详情信息'verbose_name_plural = verbose_name@propertydefproject_id(self):return self.project_info.project_id@propertydefproject_name(self):return self.project_info.project_name# 然后在序列化器内直接调用project_id和project_name即可class ProjectDetailSerializer(serializers.ModelSerializer):class Meta:model = ProjectDetailfields = ('project_id', 'project_name', 'project_introduction',)

经验总结扩展阅读


上一篇：2023年12月8日结婚好不好 有什么注意事项

下一篇：2023年犯太岁的五大生肖