完整性错误 :(1062， "Duplicate for key 'user_id'" )

Question

我正在尝试做一些工作门户之类的事情。我希望一个用户可以申请不同的工作，但不能申请相同的工作。在这里，当一个用户申请一份工作时，他不能申请另一份工作。这就是问题所在，当我运行视图时使用我的逻辑，我得到了

"完整性错误"

.请帮助我。谢谢

model.py

class JobsApplied(models.Model):
    '''
        Events
    '''
    class Meta:
        '''
            Meta properties for this model
        '''
        app_label = 'admin'
        verbose_name_plural = 'JobsApplied'
    job = models.ForeignKey('Job', db_index=True,related_name='appliedjobs')
    user = models.OneToOneField(UserProfile)
    create_date = models.DateTimeField(auto_now_add=True)

    def __unicode__(self):
        '''
            Returns object display name
        '''
        return self.job

views.py

def job_applyview(request):
    job_id = request.POST.get('job_id')
    ## if admin have rights to apply the job please  remove "not request.user.is_staff"
    # job_id = 11
    if request.user and not request.user.is_staff:
        job = Job.objects.get(id=job_id)
        ### please enable below commands after verify
        user = UserProfile.objects.get(user__id=request.user.id)
        # applied_job = JobsApplied.objects.get(job=job, user=user)

        applied_job = JobsApplied.objects.create(job=job, user=user)
        applied_job.save(force_insert=True)
        message = "you have applied in as " + str(job.job_title)
        job_title = Job.objects.get(id=job_id).job_title
        industry_id = Job.objects.get(id=job_id)
        emp_name = IndustryProfile.objects.get(id=industry_id.industry_id).name
        email = IndustryProfile.objects.get(id=industry_id.industry_id).email
        b = StudentProfile.objects.get(user_profile=UserProfile.objects.get(user_id=request.user.id))
        name = b.name
        contact_num = b.mobile_phone
        location = b.address_line1
        if b.resume:
            resume = b.resume.url
        else:
            resume = ""
        body = '''Dear %s, n The following candidate applied for the job that you have published in Nasscom Jobs Portal.
                       n n Job Title : %s n name : %s n Contact_No : %s n Address : %s n Resume : %sn n Thanks,n  n Job Portal                   Support Team''' % (
            emp_name, job_title, name, contact_num, location, resume)
        email = EmailMessage('Job Applied', body, to=[email])
        email.send()
        form = JobForm(instance=job)
        return render_to_response(
            'admin/job.html', {'form': form, 'message': message},
            context_instance=RequestContext(request),
        )
    else:
        return redirect('/admin/')

Answer 1

你说：

一个用户可以申请不同的工作

但你实现为：

class JobsApplied(models.Model):
    # [...]
    user = models.OneToOneField(UserProfile)

当 2 个对象强链接在一起时，将使用一对一字段。在这里，你说JobApply的任何实例对应于一个唯一的用户（这似乎是正确的），但你也说任何用户都链接到1个（并且只有1个）JobApp实例。因此，在这种形式下，用户不能申请 2 个或更多工作。

这里想要的是 0..n 关系：您希望用户申请 0 个或多个作业。因此，您必须在用户配置文件模型中声明一个外键。