python - 模型内部的 IntegrityError.Django 中的 DoesNotExist 异常

Question

我尝试将网页保存到数据库，url 应该是唯一的。如果 url 已经存在，我只需要在网页类和搜索类之间创建关系。但问题是，即使数据库为空并且操作发生在 DoesNotExist 异常中，我也会不断收到此 IntegrityError。请帮我解决我的问题。

这是执行保存的 block views.py 代码。

websearch.startSearch(maxPage=2)
    for result in websearch.searchResult:
        try:
            web = Webpage.objects.get(url=result)
            searching.objects.create(webpage=web, keyword=keyword)
        except Webpage.DoesNotExist:
            web = Webpage.objects.create(url=result)
            searching.objects.create(webpage=web, keyword=keyword)

这是网页和搜索模型

class Webpage(models.Model) :
    "webpage from search result and client's websites"
    domain = models.ForeignKey(Domain, blank=True, null=True)
    webhosting = models.ForeignKey(WebHosting, blank=True, null=True)
    url = models.URLField(max_length=250, blank=False, unique=True)
    html_page = models.TextField(blank=True, null=True)
    inspect_status = models.BooleanField(blank=True)
    scam_status =  models.BooleanField(blank=True)
    report_status =  models.BooleanField(blank=True)
    access_status =  models.BooleanField(blank=True)
    whitelist_status =  models.BooleanField(blank=True)
    compare_to = models.ForeignKey('self', blank=True, null=True)
    def __unicode__(self):
        return self.url

class searching (models.Model):
    'information on each searching activity'
    keyword = models.ForeignKey(Keyword, blank=True, null=True)
    token = models.ForeignKey(Token, blank=True, null=True)
    webpages = models.ForeignKey(Webpage)
    date = models.DateField(auto_now=True)
class comparison(models.Model):
    '''comparing website to other websites with the same event and label'''
    source = models.ForeignKey(Webpage, related_name='compare_source')
    destination = models.ForeignKey(Webpage, related_name='compare_destination')
    time = models.DateTimeField(auto_now=True)
    fuzz_ratio = models.FloatField()
    fuzz_partial_ratio = models.FloatField()
    fuzz_token_sort_ratio = models.FloatField()
    fuzz_token_set_ratio =  models.FloatField()
    difflib_ratio =  models.FloatField()
    difflib_quick_ratio =  models.FloatField()
    difflib_real_quick_ratio =  models.FloatField()
    levenshtein_ratio =  models.FloatField()
    levenshtein_seqratio =  models.FloatField()

Answer 1

你不需要处理异常，你可以使用 get_or_create 内置函数。

websearch.startSearch(maxPage=2)
    for result in websearch.searchResult:

         webpage, created = Webpage.objects.get_or_create(url=result)
         #webpage is a instance 
         #created is True is a new instance was created or False if it already existed. 

还有，你打错了

searching.objects.create(webpage=web, keyword=keyword)

应该是

searching.objects.create(webpages=web, keyword=keyword)

Searching对象有webpages属性，不是网页，需要添加's'