擅长:python、mysql、java
<p>你的命名约定有点混乱。inquiry_ref是您的ReferenceProperty名称和back reference集合名称,因此问题查询给你一个礼物钥匙,但是问题查询.inquiry_ref为您提供一个筛选到InquiryQuestion实体的查询对象。在</p>
<p>假设我们有以下领域模型,文章和评论之间有一对多的关系。在</p>
<pre><code>class Article(db.Model):
body = db.TextProperty()
class Comment(db.Model):
article = db.ReferenceProperty(Article)
body = db.TextProperty()
comment = Comment.all().get()
# The explicit reference from one comment to one article
# is represented by a Key object
article_key = comment.article
# which gets lazy-loaded to a Model instance by accessing a property
article_body = comment.article.body
# The implicit back-reference from one article to many comments
# is represented by a Query object
article_comments = comment.article.comment_set
# If the article only has one comment, this gives us a round trip
comment = comment.article.comment_set.all().get()
</code></pre>