Django关于事务transaction.atomic()的使用方式

from django.shortcuts import render
from django.http import HttpResponse
from django.views import View
from django.db import transaction   # 导入事务

class MyView(View):
    @transaction.atomic
    # transaction.atomic装饰器可以保证该函数中所有的数据库操作都在一个事务中。
    def post(self, request):
        # 数据库操作1。。。
        # 数据库操作2。。。
        return HttpResponse('ok')

class MyView2(View):
    @transaction.atomic
    def post(self, request):
        # 设置事务保存点
        s1 = transaction.savepoint()   # 可以设置多个保存点
        # 数据库操作。。。
        # 事务回滚 (如果发生异常,就回滚事务)
        transaction.savepoint_rollback(s1)  # 可以回滚到指定的保存点
        # 提交事务 (如果没有异常,就提交事务)
        transaction.savepoint_commit(s1)
        # 返回应答
        return HttpResponse('ok')

def func(request):
    with transaction.atomic():
        sid = transaction.savepoint()
        try:
            serializer.is_valid(raise_exception=True)
            comment = serializer.save()
            handle_obj_files(comment, request)
            visitor_order.epilogue.add(comment)
            visitor_order.status = 'complete'
            visitor_order.save()
        except Exception as e:
            transaction.savepoint_rollback(sid)
            return api_bad_request(str(e))
        else:
            transaction.savepoint_commit(sid)
        data = VisitorOrderRetrieveSerializer(visitor_order).data
        return api_success(data=data)

            with transaction.atomic():
                issue_field = After.objects.get(id=issue_field_id)
                issue_field.is_abandoned = True
                issue_field.save()
                # if set is_abandoned to True, set all field value with this field is_abandoned to True
                all_issue_field_value = AfterSales.objects.update().filter(field=issue_id)
                for issue= in all_issue:
                    issue.is_abandoned = True
                    issue.save()