擅长:python、mysql、java
<p>我希望你看到的是:</p>
<pre><code>uid = User.objects.get(username='Greg').id
pinyin = Pinyin.objects.get(pinyinWord='kuai')
learned, created = Learned.objects.get_or_create(pinyinWord=pinyin.pinyinWord,
user__id=uid)
if created: # newly INSERTed Learned instance
learned.date = datetime.date.today()
learned.learned = False
learned.save()
</code></pre>
<p><a href="http://docs.djangoproject.com/en/dev/ref/models/querysets/#get-or-create" rel="nofollow"><strong>Model.objects.get_or_create</strong></a>方法首先尝试一个<strong>模型.objects.get</strong>使用提供的参数调用。如果失败,将创建对象,并且<em>created</em>将为True,否则<em>created</em>为False。在</p>
<p>因为这是对两个字段的精确查找(例如,不是拼音单词帴u包含的),所以当没有学习实例满足这两个字段时,它将失败。然后它就被创造出来了。在</p>
<p>之后,您可以设置日期等并保存实例。在</p>